WO2025031528A1 - Method and device for making accessible the interior of a closed battery housing, in particular for electric vehicles, and battery housing for same - Google Patents

Abstract

The invention relates to a method for making accessible the interior of a closed battery housing (1), in particular of electric vehicles, in particular during the recycling and/or repair of the battery, wherein on a cover (2) or on an outer surface of the closed battery housing (1) at least one engagement element (3) is arranged in the region of the outer side of the battery housing (1), and a lifting device (15) via the at least one engagement element (3) exerts a force (17), directed away from the battery housing (1), onto the cover (2) or outer surface, as a result of which, preferably under the influence of cold (11, 14), the cover (2) or the outer surface is mechanically separated and lifted from the remainder of the battery. The invention also relates to a device suitable for this and to a correspondingly designed battery cover (1).

Description

Method and device for making the interior of closed battery housings accessible, in particular for electric vehicles, and battery housings therefor

Description

The invention relates to a method for making the interior of closed battery housings accessible according to the preamble of claim 1 and to a device suitable for carrying out the method according to the preamble of claim 28 and a battery housing therefor according to the preamble of claim 50.

The manufacture of batteries has become increasingly important due to the mass production of electric vehicles. In addition, the ranges required for electromobility to be accepted by customers mean that the batteries need to have charging capacities, which require the interconnection of a large number of individual cells of the same design, which are connected together to form a vehicle battery and operated together. There are various battery and cell shapes that are currently in use for this purpose.

Due to the weight of such batteries or accumulators in a vehicle battery, it is necessary to arrange and hold the individual cells in such a way that the arrangement is compact and stable even in dynamic driving situations. Such individual cells are either inserted into appropriate, sometimes complex holders and are individually fastened and connected there. Arrangements of individual cells are increasingly being used in a vehicle battery that are permanently connected to one another and form a kind of solid block. Blocking individual cells in this way can be achieved, for example, by gluing or casting the individual cells together after the desired arrangement has been created. For example, Tesla has developed vehicle battery designs in which the individual cells consist of cylindrical units with a round cross-section and a large number of such cylindrical units are inserted into a battery box in a matrix-like manner and spaced apart from one another. The individual cells therefore form a row and column-shaped series of cylindrical units, for example, with the cylindrical edges of the individual cells being spaced apart from each adjacent individual cell. A liquid and thermally conductive adhesive is introduced, e.g. pressed, into this usually small gap, which seals the intermediate

confirmation copy space and fix the individual cells in their spaced arrangement after curing.

Regardless of how the arrangement of the individual cells within the battery is created and secured, the battery is usually sealed off from the environment using a battery box that completely encloses and encapsulates the arrangement of battery cells. Such battery boxes are usually made from particularly thermally conductive materials such as aluminum sheets and are designed to be stable enough that the battery box also protects the individual cells against mechanical stress, for example due to accidents, and ideally remains sealed even after accidents. This also reduces the fire risk of such batteries, which are particularly flammable due to the materials used, such as lithium.

The battery boxes are usually designed in such a way that the individual cells can be installed from one direction within the trough-like, recessed and sealed battery box and can be contacted with one another and, if necessary, glued or cast as described, and then the battery box is sealed off on the open installation side by a cover. In order to attach the cover to the battery box as airtight as possible, it is glued flat to at least the associated edges of the battery box. In the case of batteries made from individual cells glued and cast together, for example, the battery cover is usually glued over the entire inner surface, the simplest way being that the casting compound for attaching the individual cells to one another is filled so far inside the battery box that it comes into contact with the surface of the cover of the battery box lid facing the inside and glues this directly to the casting compound between the individual cells. As a result, after the glue has set, the battery box, individual cells and cover form a largely completely glued unit that is mechanically very stable. Even if the individual cells are not completely encapsulated/glued, the lid and battery box can be glued in many places, e.g. to struts, reinforcements, ribs or the like, in order to ensure a high mechanical stability of the battery.

However, the main disadvantage of this design is that when this type of vehicle battery is later recycled, the individual cells have to be separated again in order to access and recover the expensive and limited battery raw materials. It can also be advantageous when repairing vehicle batteries to specifically remove individual cells in such a spaced arrangement of individual cells. to be able to replace batteries that are not functioning properly or are no longer functioning properly due to defects. However, this also requires that individual cells cast as described can be removed from the described assembly in a targeted manner and with as little manipulation of the rest of the vehicle battery as possible.

However, in order to access the inside of the battery box with the individual cells to be recycled or replaced without having to destroy the entire battery, e.g. by shredding it, the lid of the battery box must be able to be opened again. In the case of lids that are only glued on the edges, this may be possible using thermal processes with necessary temperatures of around 250 °C (80 °C must not be exceeded on the inside of the lid under any circumstances), with which the contact area between the edge of the battery box and the battery box lid is either heated and the adhesive is softened, or the contact area between the edge of the battery box and the battery box lid is cooled significantly and the adhesive is embrittled. In this edge area with the softened or embrittled adhesive, the contact between the edge of the battery box and the battery box lid can then be mechanically separated and the battery box lid can then be removed from the battery box.

The separation of bonded components, such as the individual cells of the vehicle battery, is often problematic. For example, it is known from WO 2021/259424 A1 that body components can be separated by using cold and an additional short mechanical impact. The functionality of the adhesive is reduced so much by the cold that the components can be easily removed, e.g. by lightly hitting the adhesive joint with a chisel. Surrounding components or adhesive joints are not damaged in the process, and the full functionality of the adhesive joint is fully restored after a short warm-up by the ambient temperature.

In order to reduce the temperature of objects, a cooling medium is generally used which is first brought to a low temperature and then brought into direct or indirect cold-transporting contact with the object, e.g. liquid carbon dioxide after expansion as a cooling medium in the form of cold gas with dry ice components. For example, it is known from DE 10 2007 052 390 B4 to expand liquid carbon dioxide into carbon dioxide gas with dry ice particles in order to cool a surface to be cooled to temperatures of approx. -30°. During expansion, a mixture of carbon dioxide gas and carbon dioxide snow is formed from the liquid carbon dioxide, with the carbon dioxide snow enabling a particularly improved cold transfer to the surface to be cooled. In addition, it is known to add a cold-stable liquid in the area of evaporation of the liquid carbon dioxide, which enables further cooling and particularly intensive transfer of the cold to the surface to be cooled.

In the case of battery box covers that are glued over the entire surface or over larger sections as described above, a small-area separation is not possible. In addition, thermal heating inside the cover is also not permitted due to the thermally sensitive individual cells underneath.

The object of the present invention is therefore to provide a method and a device with which a safe and effective access to the interior of closed battery housings is possible in order to enable recycling or repair of the vehicle battery.

The solution to the problem according to the invention arises with regard to the method from the characterizing features of claim 1 and with regard to the device from the characterizing features of claim 28 and with regard to a battery housing from the characterizing features of claim 50, each in conjunction with the features of the associated preamble. Further advantageous embodiments of the invention arise from the subclaims.

The method according to the invention is based on a method for making the interior of closed battery housings, in particular of electric vehicles, accessible, in particular during recycling and/or repair of the battery. Such a generic method is further developed in that at least one attack element is arranged on a cover or on an outer surface of the closed battery housing in the area of the outside of the battery housing, and a lifting device exerts a force directed away from the battery housing on the cover or the outer surface via the at least one attack element, whereby the cover or the outer surface is mechanically separated from the rest of the battery and lifted off, preferably under the influence of cold. The attack element is or will be connected to the cover or to an outer surface in such a way that a force can be transmitted from the lifting device to the cover or the outer surface, and forces can thereby be transmitted to the cover or the outer surface, which enable the cover to be released from the battery housing. When the term cover is used for simplicity in the following, the cover of the battery or an outer surface of the battery is always to be referred to with meant. The attack element(s) can be advantageously arranged on the cover or the outer surface in such a way that the force application of the lifting device enables the best effect for opening the battery casing. This release of the cover or the outer surface can take place under the influence of cold, which embrittles the adhesive between the cover and the battery casing or the interior of the battery and, for example, breaks the bond due to impact or shock-like mechanical stress in the area of the joint between the cover and the battery casing or the interior of the battery. If a first area of the cover or the outer surface has been separated, a force directed away from the battery casing can continue to be exerted on the lifted edge area of the cover in this tongue-like lifted area via the attack element. This force serves to assist the further separation of the cover from the battery casing or the interior of the battery. Figuratively speaking, the cover is peeled off the battery casing or the interior of the battery when cold is applied due to the shock and impact loads on the embrittled adhesive and is thus gradually separated by the cover being gradually lifted off the battery under the force of the lifting device until the cover is essentially completely detached from the battery and can be separated from the battery box. The inventive procedure only ever requires local mechanical loads on the adhesive embrittled by cold, with the result that the adhesive bond between the cover and the battery casing or the interior of the battery is always loosened a little and the effect of the lifting device keeps the cover in a state lifted off the battery. The lifting effect of the lifting device supports and ensures the local separation of the embrittled adhesive. By gradually shifting the point of attack of the mechanical stress on the adhesive, which has become brittle due to cold, the adhesive can be separated from the cover, figuratively speaking, in the area of the root of the tongue-like lifted area, and the cover can thus be gradually removed. Handling the released area of the cover is made easier by the lifting device, as the released area of the cover is always moved away from the battery casing and thus the area of effect of the mechanical stress. This means that even large and fully bonded covers can be removed from the battery with manageable effort and the interior of the battery casing can be accessed with only minimal damage.

In a first conceivable design, it is possible that the at least one attack element is permanently attached to the cover or the outer surface of the battery housing is attached. This means that during the manufacture of the battery, it can be ensured that a mechanical attack can be carried out on the attack element(s) in order to ensure optimal mechanical conditions for opening when the battery casing is opened, e.g. for recycling or repair. More than one attack element can also be distributed over the lid or the outer surface in order to enable optimal force attacks for different areas of the lid or the outer surface of the lifting device that can be connected to the respective attack element. The lifting device can be connected to different attack elements on the lid or the outer surface as the battery casing is opened.

It is particularly important in one embodiment if the lifting device and the attack element have matching transmission elements with which the force of the lifting device directed away from the battery housing is transferred via the attack element to the cover or the outer surface. The transmission elements should firstly ensure that the lifting device and the attack element are assigned in a precise position and secondly be able to safely transfer the forces required to open the battery housing from the lifting device to the attack element. In this case, it is conceivable to implement the force transmission in a force-locking manner, for example via pliers-like clamping elements that engage tab-shaped attack elements. However, it can be advantageous if the attack elements are equipped with form-locking transmission elements and the transmission elements of the lifting device engage in a form-locking manner in the matching transmission elements of the attack element(s). This enables both a precise position and a high force transmission between the lifting device and the attack elements. Thus, in a conceivable embodiment, the at least one engagement element can extend in at least one edge region of the lid, preferably in a linear manner, be arranged on the outside of the lid or the outer surface and be designed with hole-like depressions as transmission elements in the strip-shaped element, into which, for example, hook-like transmission elements of the lifting device engage.

In another embodiment, it is conceivable that the at least one engagement element with transmission elements is designed in the form of hole-like depressions in the material of the cover or the outer surface itself in the area of a projection of the cover or the outer surface over the outer boundaries of the battery housing. For this purpose, the cover can be designed on one edge of the battery housing in such a way that it protrudes a little over the actual edge region like a tab. area of the battery housing. Hole-like recesses can be made in this tab-like area, for example, into which hook-like transmission elements of the lifting device can engage and thereby release the cover from the battery housing. This area can be reinforced to increase the possible force transmission, preferably reinforced with a correspondingly perforated rail or the like, so that the holes in the cover area are prevented from tearing out due to the force transmission by the hook-like transmission elements of the lifting device.

It is also advantageous if the cover or the outer surface is lifted off the battery housing in a tongue-like manner by the engagement of the lifting device on the at least one engagement element.

In another embodiment of battery housings, it is also conceivable that at least one edge region of a cover or an outer surface of the closed battery housing is mechanically separated from the rest of the battery, preferably under the influence of cold, and lifted off like a tongue, a holding device is attached to this tongue-like lifted edge region along the edge of the cover, which exerts a force directed away from the battery housing onto the lifted edge region of the cover via a lifting device, and in the area of the root of the tongue-like lifted edge region, further sections of the cover are mechanically detached from the battery by the supply of cold and are lifted off the battery by the force of the lifting device until the cover is essentially completely detached from the battery and can be separated from the battery housing. In this case, starting from an edge region of the battery cover or another surface of the battery housing that has previously been manually detached from the battery housing, for example, this edge region is detached to such an extent that a tongue-like exposed edge section of the cover results. This manual loosening of the edge section can be carried out under the influence of cold, which embrittles the adhesive between the cover and the battery casing or the interior of the battery and, for example, breaks the bond through impact or shock-like mechanical stress in the area of the joint between the cover and the battery casing or the interior of the battery. If such a tongue-like lifted area has been separated manually, a holding device can then be attached to this tongue-like lifted area, e.g. along the edge. This holding device is then used to mechanically couple a lifting device, which exerts a force directed away from the battery casing onto the lifted edge area of the cover via the holding device. This force serves to support the further separation of the cover from the battery casing or the interior of the battery, which is carried out mechanically in the area of the root of the tongue-like raised edge area with the addition of cold, for example by impact and shock loads on the embrittled adhesive between the cover and the battery casing or the interior of the battery on other sections of the cover. This also allows battery casings to be opened according to the invention that do not have any attack elements themselves. The holding device that can be attached to the cover essentially retrofits the attack element to the cover, and this also allows battery casings to be opened according to the invention that have, for example, smooth covers without attack elements.

It is particularly advantageous if the holding device is glued to the edge of the lid in the area of the tongue-like raised edge area. This can be done using a silicone adhesive or other suitable adhesive substances with lower glass breaking temperatures and ensures a flat connection between the edge area of the lid and the holding device.

In another embodiment, it is also conceivable that the holding device clamps the lid in the area of the tongue-like raised edge area. For example, the holding device can grip around the lid in the area of the tongue-like raised edge area and clamp it between itself. It is also conceivable that the edge area of the lid and the holding device are screwed together, for example with the help of a rod with threads that is attached to the holding device using screws and clamps the tongue-like raised edge area. This enables a mechanically stable and resilient connection between the lid and the holding device that does not require an adhesive to harden and can also be easily removed again.

It is advantageous here if additional cold is introduced into the area between the cover and the interior of the battery, which embrittles the adhesive between the cover and the interior of the battery in a targeted manner in the areas that are to be separated from one another by mechanical intervention. This means that only a particularly large amount of cooling of the adhesive is required locally in order to bring the embrittlement to the level that is particularly advantageous for mechanical separation, as far as possible in the respective work area. In one embodiment, the cold when separating the cover from the interior of the battery can be introduced directly into the area of the root of the tongue-like raised edge area, preferably directly at the adhesive in the area of the root, and then acts directly on the adhesive. However, it is also conceivable to introduce the cold from the area opposite the adhesive connection. overlying side of the lid and thereby indirectly cool the adhesive bond. A combination of both options is also conceivable.

In another embodiment, however, it is also conceivable that the cover or the outer surface is lifted off the battery housing largely over its entire surface by the simultaneous attack of the lifting device on preferably several attack elements. In this case, a significantly greater force is used than with the successive peeling off of the cover and the simultaneous and large-area attack of the lifting device on the cover, ensuring that the cover is virtually torn off the battery housing. For this purpose, for example, several attack elements can be arranged distributed on the cover and actuated simultaneously by the lifting device. However, it is also conceivable to arrange a single attack element on the cover, which largely extends over large parts or the entire cover, and to attack it with a lifting device that also has an equally large area and to tear the cover off the battery housing in one go.

In another embodiment, however, it is also conceivable that at least one surface gripper acting by means of negative pressure is fixed to the cover or the outer surface as an engagement element, preferably a suction gripper, via which the lifting device engages the cover or the outer surface and separates the cover or the outer surface from the battery housing. Such a suction gripper can exert high forces on a flat surface such as the battery cover by means of appropriate negative pressure and thus transfer the mechanical forces of the lifting device acting on the suction gripper to the cover. This would make it possible to exert mechanical forces on the battery cover without changing the battery cover.

It is advantageous if the cover is pre-cooled from outside the battery at least in some areas before being lifted off the inside of the battery. Full or partial pre-cooling of the adhesive, for example by means of cooling devices arranged on the outside of the cover or acting on it, such as cooling nozzles, cooling elements, cooling pads or cooling baths, allows the adhesive to be removed to be cooled easily, so that any additional cooling effect that can be introduced into the respective area of mechanical stress on the adhesive bond only has to effect the residual cooling, thus enabling faster operation. For example, the cover can be designed to be recessed like a trough by edges bordering the outside of the cover in order to hold coolant or similar coolant applied, preferably by cooling nozzles, on the cover. This creates a type of cooling bath on the cover, which is continuously cooled, for example, via the cooling nozzles. can be refreshed and enables intensive cooling of the adhesive under the lid, resulting in strong embrittlement of the adhesive.

It can be advantageous here if additional cold is introduced into the area between the cover and the interior of the battery, which embrittles the adhesive between the cover and the interior of the battery in a targeted manner in the areas that are to be separated from one another by mechanical intervention. This means that only a particularly large amount of cooling of the adhesive is necessary locally in order to bring the embrittlement to the level that is particularly advantageous for mechanical separation, as far as possible in the respective work area. In one embodiment, the cold when separating the cover from the interior of the battery can be introduced directly into the area of the root of the tongue-like raised edge area, preferably directly on the adhesive in the area of the root, and then acts directly on the adhesive. However, it is also conceivable to introduce the cold from the side of the cover opposite the adhesive connection, thereby indirectly cooling the adhesive connection. A combination of both options is also conceivable.

In an advantageous embodiment, it is conceivable that the mechanical separation between the cover and the interior of the battery is caused by impact- or shock-loadable separating tools, in particular by chisels. The impact- or shock-like loading of cooled and thus embrittled adhesive bonds is generally known and enables, for example, in the case of bonded body parts, a gentle separation of such adhesive bonds without permanently impairing the material properties. Such separating tools also have the effect that they can be pushed like a type of spreading device between the interior of the battery and the cover or between the battery housing and the cover and also push the cover away from the interior of the battery. This is also advantageous, especially when the cover is first opened, in order to promote the local failure of the embrittled adhesive. The separating tool can also be designed with a greater or lesser width in order to mechanically load a shorter or longer line of engagement between the cover and the interior of the battery.

It is conceivable that the separating tool is moved manually or automatically in the area between the interior of the battery and the cover. Manual guidance of the separating tool has the advantage that work can be carried out in a targeted manner depending on the progress of the separation, but requires the work of a worker and a certain amount of experience. Automatic guidance of the separating tool, for example in a line always along the root of the respective tongue-like raised edge area is more economical, but may require additional control effort to ensure that the lid is separated as intended.

It is also conceivable that the mechanical separation between the cover and the interior of the battery is achieved by means of an impact and/or vibration load, preferably a vibration in the area of the cover, in particular in the area of the tongue-like raised edge area of the cover. For example, a vibrating tool can cause the cover or sections of the cover itself to vibrate in such a way that the embrittled adhesive in the respective area of the bond to be separated is subjected to such mechanical stress that it tears open and the cover and the interior of the battery are separated at this point. This further protects the interior of the battery, as only the cover is mechanically stressed, without a tool being able to penetrate into the interior of the battery and damage any functional components that may be present there. The separation tool can also vibrate.

It is definitely an advantage if a nozzle for introducing cold into the area between the interior of the battery and the cover is moved together with the separation tool. This means that the cold is always automatically introduced into or near the respective separation area on the cover or in the area of the root without the need for additional handling operations.

It is also conceivable that the cold is introduced with the help of sublimating liquid carbon dioxide, preferably with the addition of a cold-stable liquid, via a nozzle, preferably into the area between the interior of the battery and the cover.

The invention further describes a device for making the interior of closed battery housings, in particular of electric vehicles, accessible, in particular during recycling and/or repair of the battery, in particular for carrying out the method according to claim 1, wherein at least one engagement element is arranged on a cover or on an outer surface of the closed battery housing in the region of the outside of the battery housing, and a lifting device engages the at least one engagement element in such a way that a force directed away from the battery housing acts on the cover or the outer surface, which, preferably under the influence of cold, mechanically separates the cover or the outer surface from the rest of the battery and lifts it off. Essential properties and advantages of such a device have already been explained in connection with the method described above and, in order to avoid repetition, are hereby also referred to for the device. In a first embodiment, it is conceivable that the lifting device engages the at least one engagement element arranged on an edge region of a cover or an outer surface in such a way that the lifting device mechanically separates the edge region from the rest of the battery and lifts it off like a tongue. In this case, the cover is gradually opened further and further, starting from an edge region, so that the separation of the cover from the adhesive always takes place more locally and gradually.

In another embodiment, it is also conceivable that the lifting device preferably engages several attack elements in such a way that the lifting device lifts the cover or the outer surface largely over the entire surface from the battery housing through the simultaneous attack. This means that the cover is torn off the entire surface from the inside of the battery and separated from the inside of the battery in one fell swoop. This requires greater forces between the lifting device and the attack elements, but also speeds up the process overall.

In another embodiment for any battery box, at least one edge region of a lid or an outer surface of the closed battery housing can be mechanically separated from the rest of the battery and lifted off like a tongue, preferably under the influence of cold. A holding device is attached to the lifted edge region of the lid along the edge-side, tongue-like lifted edge, and a lifting device engages the holding device and thus the lid in such a way that a force directed away from the battery housing acts on the lifted edge region of the lid, with at least one separating tool engaging in the region of the root of the tongue-like lifted edge region with the supply of cold and mechanically detaching further sections of the lid from the battery, and the force of the lifting device lifts these detached sections from the battery until the lid is essentially completely detached from the battery and separated from the battery housing. This makes it possible to open battery boxes on which attack elements are not already arranged due to the design.

In one embodiment, it is conceivable that the holding device has a preferably L-shaped angle, which is attached with one leg to the previously tongue-like raised edge area of the lid and with the other leg to a lifting device. The design of the holding device as, for example, an L-shaped angle has the advantage that one leg of the angle can be used to attach to the raised edge area of the lid, whereas the other other leg offers a favorable attack area for the attack of the lifting device.

Thus, in one conceivable embodiment, the holding device can have a clamping device on one leg, which is arranged on the tongue-like raised edge area of the lid, with which the tongue-like raised edge area of the lid is clamped to the holding device, for example by the clamping device having a rod-like clamping bracket that presses the tongue-like raised edge area of the lid against the holding device. The holding device can thus be easily attached to the raised edge area of the lid for preparation, but can also be released again after the separation process has been completed and still ensure a secure transmission of force from the lifting device to the lid.

In a further embodiment, it is conceivable that the lifting device has a pulling device that pulls the lifted edge area of the cover away at an angle to the cover surface with at least one component perpendicular to the cover surface. The pulling device here puts a tensile load on the brittle adhesive bond between the cover and the interior of the battery housing in a direction that, on the one hand, supports the separation of the adhesive bond by the mechanical action of a separating tool and, in addition, keeps the already separated sections of the cover away from the advance of the respective impact zone of the mechanical load by the separating tool, thereby improving the accessibility of this respective impact zone. Such an obliquely acting tensile force could, for example, act at an angle of approximately 70° to the cover surface.

In a further embodiment, such a pulling device can have a pull rod, preferably hydraulically or pneumatically or electrically actuated, which is attached to the holding device via pulling elements and pulls the cover away from the latter with at least one component perpendicular to the cover surface. Such a pulling device can be arranged, for example, at one end of the battery housing in a fixed position or can be adjusted in the longitudinal direction of the battery and can be connected to the holding device and attached to it, for example, via ropes or rods. A hydraulically or pneumatically actuated pull rod can exert high forces on the sections of the cover that have already been separated from the adhesive and the cover can be pulled away from the battery housing. The pulling device can be designed in such a way that the pulling force can be changed during the separation process and adapted to the respective separation behavior of the adhesive. In another embodiment, however, it is also conceivable that the lifting device has a winding device that successively winds up the tongue-like lifted edge area of the cover away with at least one component of the direction of rotation perpendicular to the cover surface and moves along the battery housing. The winding has a similar effect on the exposed sections of the cover as with the pulling device, but at the same time ensures a compact and space-saving winding up of the cover with a synchronization of the winding axis to the work progress of separating the cover.

In a further embodiment, it is conceivable that the separating tool is guided manually and/or automatically and the impact or striking movement of the separating tool is carried out manually and/or automatically. The separating tool can be repositioned by a worker in the area of the separation zone, for example, who can identify where further impact or shock load from the separating tool has the greatest effect or where the lid has not yet been sufficiently separated. Automatic guidance of the separating tool, on the other hand, offers the advantage of being able to fully or partially automate the separation process and thus make it more economical. The automatic execution of the impact or striking movement, e.g. using hydraulic, pneumatic or mechanical energy, relieves the worker and is a prerequisite for automatic separation. In addition, it can be helpful for the first opening of the lid if the separating tool is placed under pre-tension on the area between the lid and the battery housing and presses firmly against this area under pre-tension. The first impact or striking movement of the separating tool is then applied directly to the area between the lid and the battery housing and can immediately separate the lid and battery housing locally without any loss of energy.

It is particularly advantageous if the cutting edges of the separating tool, in particular a chisel, are designed in such a way that the separating tool is pressed against the inside of the cover and guided along the inside of the cover when subjected to mechanical impact or shock. Since the adhesive between the cover and the inside of the battery always has a certain thickness and the removal of the cover should take place without damaging the inside of the battery, it is advisable to let the separating tool slide along the usually quite solid cover and thus guide it as far away from the inside of the battery as possible. For this purpose, it is advantageous if the separating tool or chisel has bevels with different bevel angles. This allows for example, the wedge-shaped cutting area of the cutting tool or chisel has a wedge surface intended for contact with the battery cover with a wedge angle of essentially 0° and a wedge surface with a wedge angle of more than 0°. As a result, the cutting tool or chisel is pressed in one direction, namely towards the cover, by the cutting tool or chisel sliding on the adhesive layer and, figuratively speaking, works its way through the adhesive layer, guided by the inner surface of the cover. Such asymmetrically shaped cutting tools or chisels can have different wedge angles depending on the material of the adhesive and can be adapted to different processing situations by varying the wedge angles.

In another embodiment, however, it is also conceivable that the lifting device has a manipulator, preferably one that can be moved automatically, which engages the at least one engagement element and pulls the cover away, preferably at an angle to the cover surface, with at least one component perpendicular to the surface of the cover. Such a manipulator provides the required movement devices and forces that are required for a safe execution and, if necessary, variation of the release of the cover from the battery housing and also offers the possibility of being able to easily adapt its movements to different conditions such as different adhesive properties, geometric dimensions of the battery housing, etc.

In a further embodiment, the manipulator can have at least one fork-like or prong-like arrangement of transmission elements that engage in matching hole-like recesses on the at least one engagement element and hold them. Such a positive coupling of the manipulator to the engagement element ensures that the transmission elements are precisely assigned to one another, even if the geometry of the lid changes when it is lifted off, and at the same time a high transferable force on the lid.

In a further embodiment, the manipulator can, in addition to the pulling movement, carry out a rotational movement with at least one component perpendicular to the surface of the lid, with which the lid can also be tilted sideways. By turning the manipulator sideways, the fork- or prong-like arrangement of the manipulator's transmission elements can, figuratively speaking, tilt sideways, so that the forces on the section of the adhesive to be released vary and a shorter tear-off edge of the adhesive is caused to be released. This simplifies the release of the adhesive, since the forces acting are transferred to a shorter length of the tear-off edge. By changing the loading In addition, due to the tilting, the direction of force within the adhesive is repeatedly changed, which causes the adhesive to fail additionally due to the dynamic load.

It is particularly important if the battery housing is opened in a closed cabin by introducing an inert gas, preferably carbon dioxide gas, and displacing the ambient atmosphere from the cabin. In this case, the unopened battery housing is brought through locks or similar into a cabin that is closed off from the environment and can be flooded with an inert gas. This displaces the ambient air and the oxygen it contains from the cabin, thus providing an essential part of the fire and explosion protection. In addition, any coolant used is kept inside the cabin and can be specifically extracted after the battery housing is opened and reused after appropriate processing and separation from the air components. In addition, when using carbon dioxide as an inert gas, for example, the ambient air is displaced upwards inside the cabin due to the higher specific weight of carbon dioxide compared to air, and can be specifically extracted there until only carbon dioxide is extracted.

The invention further relates to a battery housing for a battery, in particular a battery for electric vehicles, in which at least one engagement element is arranged on a cover or on an outer surface of the closed battery housing in the area of the outside of the battery housing for a lifting device, with which the cover or the outer surface can be separated from the battery housing. In particular, by preferably permanently attaching such an engagement element, the battery housing can be equipped during manufacture so that it can be opened again for recycling or repairs without completely destroying the battery. If, in a further embodiment, the lifting device and engagement element have matching transmission elements with which the force of the lifting device directed away from the battery housing is transmitted via the engagement element to the cover or the outer surface, the force of the lifting device can be controlled in a targeted manner so that only the cover lifts off the battery housing without causing undue impairment of the interior of the battery and the battery can thus be opened and closed again for repairs, for example. As part of recycling, the The interior of the battery casing can be opened in a targeted manner and components to be recycled can be removed in a targeted manner and without destruction.

Such engagement elements can be arranged in at least one edge area of the cover, preferably extending in a line, e.g. as a strip-shaped element with hole-like depressions. However, it is also conceivable that the at least one engagement element is formed from hole-like depressions in the material of the cover itself or the outer surface in the area of an overhang of the cover or the outer surface over the outer boundaries of the battery housing. For this purpose, the cover is designed to be slightly larger than the battery housing and thus protrudes at least partially like a tab over the battery housing. Engagement elements arranged in this area, e.g. designed as perforations, then serve for the engagement by the lifting device. The perforations or even the entire tab-like protruding area of the cover can be reinforced, preferably with a correspondingly perforated rail or the like.

For longer cooling of the adhesive to be removed, it is conceivable that the lid or the outer surface is designed in a trough-like manner with edges on the outside of the lid or the outer surface in order to hold cooling liquid or similar coolant, preferably applied by cooling nozzles, on the lid or the outer surface. This means that cooling liquid applied by means of cooling nozzles, for example, can be held on the lid for longer periods of time without the cooling liquid being able to run off the lid, and the cooling liquid can therefore transfer its cold to the adhesive to a high degree.

A particularly preferred embodiment of the method according to the invention and the device suitable therefor is shown in the drawing.

They show:

Figure 1 - a schematic representation of the structure of a device according to the invention for making the interior of closed battery housings accessible with an engagement element arranged on the lid and a fork-like lifting device,

Figure 2 - a device according to Figure 1 with a separating tool arranged on the battery housing, Figure 3 - a device according to Figure 1 with arranged on the lid

Attack element and tiltable forks of a manipulator as a lifting device,

Figure 4 - a device according to Figure 1 with holes arranged on the edge of the lid itself and angled forks of the lifting device,

Figure 5 - a trough-like edge of the lid of the battery housing for collecting and holding a cooling liquid that can be sprayed on by means of nozzles.

Figure 6 - a schematic representation of the structure of a device for

Making the interior of closed battery cases accessible,

Figure 7 - a device according to Figure 6 with cooling elements arranged on the battery housing,

Figure 8 - an enlarged view of the effective zone according to Figure 6 when making the interior of closed battery housings accessible with a separation tool.

Figure 1 shows a schematic structure of a device according to the invention for making the interior of closed battery housings 1 accessible, with which a cover 2 of the battery housing 1, which is, for example, fully bonded to the interior of the battery, can be gradually detached from this interior of the battery housing 1 and the interior of the battery housing 1 can thus be exposed. Such fully bonded battery housings 1 are one, but not the exclusive, area of application of the present invention. However, the invention will be explained using such fully bonded batteries.

The battery housing 1 has an approximately rectangular outer shape and encloses a cuboid-shaped volume in which battery cells (not shown in more detail) are arranged and glued together. The battery housing 1 has a cover 2 that can be put on after the battery cells have been fitted and contacted, whereby the cover 2 can be connected to the battery housing 1 and the interior of the battery, for example, with the same adhesive that is used to glue the battery cells together. As a result, the inner surface of the cover 2 is fully glued to the interior of the battery housing 1 or the battery and can no longer be easily removed. To release the cover 2, the method according to the invention is used, in which, for example, in an edge section of the cover 2, for example under the influence of cold (not shown here), for example by spraying liquid carbon dioxide onto the cover 2 and using separating tools 10 such as special chisels, the adhesive between the inner surface of the cover 2 and the battery becomes brittle and can then be separated by impacts or blows in the direction of impact 13 that can be introduced via the separating tool 10. The battery housing 1 is fixed in the direction of load by counterholders 4, which are only indicated schematically, and cannot move.

For this purpose, an engagement element 3 in the form of a type of strip with transversely arranged perforations 5 is attached to the cover 2, which can be attached to the cover 2 during manufacture of the battery, for example. It is conceivable to arrange only one such engagement element 3 on the edge of the cover 2 as shown in Figure 1. However, it is also conceivable to arrange several engagement elements 3 distributed over the cover 2 on this cover 2 or to arrange an engagement element 3 that extends largely over the entire or large parts of the cover 2. It is also conceivable to provide the engagement element 3 with more than two perforations 5 or to provide another design of a positive or non-positive interaction with the lifting device 15. For example, a pliers-shaped lifting device 15 could engage an unperforated tab-like engagement element 3.

In the illustration in Figure 1, the lifting device 15 is designed with two fork-shaped prongs 6 to match the holes 5 of the engagement element 3, the diameter and distance of which match the holes 5 of the engagement element 3. The prongs 6 are pushed into the holes 5 in the insertion direction 19 with the aid of movement devices not shown here, e.g. with several movement axes of the lifting device 15, and thus create a positive connection between the lifting device 15 and the engagement element 3, which can transfer the forces exerted by the lifting device 15 in the pulling direction 17 to the cover 2 and thus lead to the cover 2 being released from the battery housing 1. In the configuration shown in Figure 1, the cover 2 is released from the battery housing 1 at the edge under the engagement element 3 and forms a tongue-like released section. The section of the cover 2 which has been detached from the adhesive in this tongue-like manner is then loaded by the further force of the lifting device 15 on the engagement element 3 in the pulling direction 17, whereby the cover 2 is pulled away from the battery housing 1 at least with a vertical component. The cover 2 gradually peels off, figuratively speaking, from the inside of the battery and the adhesive, as is known for example from a tin can. This process continues until the lid 2 has completely detached from the battery casing 1.

Figure 2 shows a modification of the method according to Figure 1, in which the cover 2 is gradually released by pushing or striking the separating tool 10, which is designed as a chisel here, into the wedge-shaped area between the interior of the battery and the inner surface of the cover 2 and thus in the direction 13 into the area of the adhesive, thereby separating the embrittled adhesive. If the separating tool 10 is moved laterally along the section 16 of the cover 2 which has been released from the adhesive in a tongue-like manner and exerts the described pushes or blows in the direction 13, the cover 2 is separated a little more from the adhesive in strips and can be pulled further down and away from the battery housing 1 by the lifting device 15. In this way, the interior of the cover 2 is gradually separated from the adhesive from top to bottom and from left to right until the last connection between the cover 2 and the battery housing 1 or the interior of the battery is separated and the cover 2 can be removed. The interior of the battery housing 1 is then exposed and can be further processed to recycle battery cells or replace individual battery cells.

This improves the separation of the embrittled adhesive, as the force of the lifting device 15 causes the crack in the adhesive layer to open further and the adhesive to tear open further. On the other hand, the effective area of the separating tool 10 is opened when the bond is further loosened, and the section 16 of the cover 2 that has been detached from the adhesive like a tongue does not interfere with the further separation of the adhesive connection. In addition, such a separating tool can also be used to assist the first section of opening the cover 2 purely mechanically, by placing the separating tool 10 in the area between the battery housing 1 and the cover 2 and pushing it into this area in which the cover 2 is to be lifted off the battery housing 1 first. This makes the first loosening of the cover 2 easier and more targeted, and there is no unwanted tearing of the cover 2 in undesirable places.

The adhesive is separated under the influence of cold, which can be used to embrittle the adhesive. On the one hand, the adhesive arranged between the inner area of the cover 2 and the battery cells can be separated over the entire surface or part of the surface by means of strips arranged on the outside of the cover 2, which are only indicated in Figure 5. Cooling nozzles or the like are used to bring the lid 2 to low temperatures in advance and keep it there. Such nozzles are not shown in Figures 1 to 4 for reasons of clarity, but can of course cool parts of the lid 2 or the entire lid 2.

However, for the actual separation of the adhesive, it is important that the adhesive is then locally exposed to a very strong cooling coolant 14 in the respective effective area of the separating tool 10, e.g. through a nozzle 12, which causes a reliable embrittlement of the adhesive section to be processed locally with the separating tool 10. Here, in a manner known per se, a liquid carbon dioxide can be injected, for example, which is sublimated there and, if necessary, further cooled with a cold-stable liquid and is injected by the nozzle into the gap under the section of the cover 2 that has been separated from the adhesive in a tongue-like manner, cooling this area strongly. However, it is also conceivable to point the nozzle at the outside of the cover 2 in this section to be processed and to cool the adhesive indirectly through the cover 2. A combination of both cooling variants is also conceivable. It is sensible to move the nozzle 12 together with or parallel to the movement of the separating tool 10.

The separating tool 10, which is designed here as a chisel, can be designed with unequal wedge angles. The chisel 10 has a first wedge surface that is not inclined at all or slightly and a second wedge surface that is more inclined. If the first wedge surface that is not inclined at all or slightly is arranged opposite the inner surface of the cover 2 and the chisel 10 is operated in the impact or impact direction 13, the chisel 10 is pressed against the inner surface of the cover 2 by the second more inclined wedge surface sliding on the adhesive and is guided along it. This improves the separation of the adhesive from the inner surface of the cover 2 and the adhesive largely remains in the battery, which also minimizes the risk of damage to components inside the battery housing 1.

In Figure 3, a modification of the lifting device 15 can be seen in that the lifting device 15 with the prongs 6 can be pivoted at least a little about an axis 8 running around the insertion direction 19. After the prongs 6 have been inserted into the holes 5 of the engagement element 3 and secured by means of a pin 7, one of the lateral areas of the dividing line between the lid 2 and the adhesive can be loaded in a targeted manner by pivoting the lifting device 15 about the axis 8. The lid 2 bulges slightly as a result and the dividing line between the lid 2 and the adhesive is shortened, so that the force of the lifting device 15, which acts to the same extent, a shorter area of the adhesive is exposed to a higher load, which allows the adhesive to separate more easily from the inside of the lid 2.

Figure 4 shows a modification of the connection between the lifting device 15 and the engagement element 3, in which the engagement element 3 on the cover 2 can be formed from the material of the cover 2 itself. For this purpose, the cover 2 is designed to be slightly longer in one direction than the battery housing 1 and is attached to the battery housing 1 with a small projection 9. In the area of this projection 9, holes 5 are then made in the material of the cover 2, which, as with the engagement element 3 according to Figure 1, are intended to interact with the prongs 5 of the lifting device 15. If necessary, the cover 2 can also be reinforced in the area of the projection 9, for example thickened or reinforced with a suitably perforated strip or the like, in order to prevent the cover 2 from tearing open at the holes 5. The prongs 5 of the lifting device 15 then interact again as already described with the attack element 3 formed in this way and pull the cover 2 off the battery housing 1.

In Figure 5, a modification of the lid 2 can be seen in that the edge of the lid 2 is provided with raised edges that act as an edge 18, which makes the lid 2 look like a flat trough. This design of the lid 2 can be used to keep cooling liquid applied to the lid 2 via the nozzles 12, for example by means of sublimated liquid carbon dioxide with dry ice particles or another cooling liquid, in contact with the lid 2 for as long as possible. The lid 2, which is trough-shaped due to the edge 18, fills with this cooling medium, which cannot run off so easily and intensively cools the lid 2 and the adhesive arranged underneath.

Figures 6 to 8 show a schematic structure of another device for making the interior of closed battery housings 1 accessible. The method according to the invention is used to remove the cover 2, in which the adhesive in the edge area of the battery housing 1 and between the inner surface of the cover 2 and the battery is first embrittled in an edge section of the cover 2, e.g. under the influence of cold and using separating tools 10 such as special chisels, and can then be separated by impacts or blows in the direction of impact 13 that can be introduced via the separating tool 10. This separation of a narrow strip of the cover 2, e.g. several tens of millimeters, is typically carried out by hand. The section 16 of the cover 2 which has been detached from the adhesive in this tongue-like manner is then brought into mechanically resilient contact with an L-shaped holding device 23. The holding device 33 serves to apply a force to the section 16 of the cover 2 which has been detached from the adhesive in a tongue-like manner, which pulls the cover 2 away from the battery housing 1 with at least a vertical component. This improves the separation of the embrittled adhesive, as the force of the holding device 3 causes the crack in the adhesive layer to open further and the adhesive to tear open further. On the other hand, the effective area of the separating tool 10 is opened when the adhesive is further loosened, and the section 16 of the cover 2 which has been detached from the adhesive in a tongue-like manner does not interfere with the further separation of the adhesive connection.

In the present example, the force of the holding device 23 on the cover 2 is applied with a lifting device 15 with a hydraulic or pneumatic cylinder 25, the piston rod 26 of which is connected to the holding device 23 via rods or wires 27 or 29 and a crossbar 28. If the piston rod 26 of the cylinder 25 is retracted, the crossbar 28 and thus also the holding device 23 are pulled away from the battery housing 1 and downwards in the pulling direction 17 and the tongue-like section 16 of the cover 2 detached from the adhesive is pulled further away from the battery housing 1. For this purpose, the holding device 23 is glued to the edge section of the cover 2 or mechanically connected, for example via a clamp connection or the like.

The cover 2 is released after the initial release of the tongue-like section 16 of the cover 2, which has been released from the adhesive, by pushing or striking the separating tool 10, which is designed as a chisel, into the wedge-shaped area between the interior of the battery and the inner surface of the cover 2 and thus in the direction 13 into the area of the adhesive, thereby separating the embrittled adhesive. If the separating tool 10 is moved laterally along the tongue-like section 16 of the cover 2, which has been released from the adhesive, and exerts the described impacts or blows in the direction 13, the cover 2 is separated a little more from the adhesive in strips and can be pulled further downwards and away from the battery housing 1 by the holding device 23 and the lifting device 15. In this way, the interior of the cover 2 is gradually separated from the adhesive from top to bottom and from left to right until the last connection between the cover 2 and the battery housing 1 or the interior of the battery is separated and the cover 2 can be removed. The interior of the battery housing 1 is then exposed and can be further processed for recycling battery cells or replacing individual battery cells.

The adhesive is separated under the influence of cold, which can be used to embrittle the adhesive. On the one hand, the adhesive arranged between the inner area of the cover 2 and the battery cells can be brought to low temperatures over its entire surface or part of its surface by cooling elements 11, such as cooling pads or the like, which are only indicated and arranged on the outside of the cover 2.

However, for the actual separation of the adhesive, it is important that the adhesive is then locally exposed to a very strong cooling agent 14 in the respective effective area of the separating tool 10, e.g. through a nozzle 12, which causes a reliable embrittlement of the adhesive section to be processed locally with the separating tool 10. Here, in a manner known per se, a liquid carbon dioxide can be injected, for example, which is sublimated there and, if necessary, further cooled with a cold-stable liquid and is injected by the nozzle 12 into the gap under the tongue-like section 16 of the cover 2, which is separated from the adhesive, and cools this area strongly. However, it is also conceivable to point the nozzle 12 at the outside of the cover 2 in this section 16 to be processed and to cool the adhesive indirectly through the cover 2. A combination of both cooling variants is also conceivable. It is useful to move the nozzle 12 together with or parallel to the movement of the cutting tool 10.

The separating tool 10, which is designed here as a chisel, can be designed with unequal wedge angles, as can be seen better in the enlarged illustration in Figure 3. The chisel 10 has a first wedge surface that is not inclined at all or only slightly and a second wedge surface that is more inclined. If the first wedge surface that is not inclined at all or only slightly is arranged opposite the inner surface of the cover 2 and the chisel 10 is actuated in the impact or impact direction 13, the chisel 10 is pressed against the inner surface of the cover 2 by the second more inclined wedge surface sliding on the adhesive and is guided along it. This improves the separation of the adhesive from the inner surface of the cover 2 and the adhesive largely remains in the battery, which also minimizes the risk of damage to components inside the battery housing 1. part number list

1 battery case

2 lids

3 attack element

4 counterholders

5 holes

6 tines/fork

7 pen

8 direction of rotation

9 Overhang lid

10 chisels

11 Cooling bath/cooling element

12 nozzles

13 thrust direction

14 refrigerants

15 lifting device

16 tongue-like released section

17 pulling direction

18 Rand

19 Insertion direction

20 root

21 clamps

23 holding device

25 hydraulic cylinders

26 piston rod

27 rods

28 crossbar

29 rods

Claims

patent claims 1. Method for making the interior of closed battery housings (1) accessible, in particular of electric vehicles, in particular during recycling and/or when repairing the battery, characterized in that at least one attack element (3) is arranged on a cover (2) or on an outer surface of the closed battery housing (1) in the region of the outside of the battery housing (1), a lifting device (15) exerts a force (17) directed away from the battery housing (1) on the cover (2) or the outer surface via the at least one attack element (3), whereby the cover (2) or the outer surface is mechanically separated from the rest of the battery and lifted off, preferably under the influence of cold (11, 14). 2. Method according to claim 1, characterized in that the at least one engagement element (3) is permanently attached to the cover (2) or the outer surface of the battery housing (1). 3. Method according to one of claims 1 or 2, characterized in that the lifting device (15) and the attack element (3) have matching transmission elements (5, 6) with which the force (17) of the lifting device (15) directed away from the battery housing (1) is transmitted via the attack element (3) to the cover (2) or the outer surface. 4. Method according to one of the preceding claims, characterized in that the at least one engagement element (3) is arranged in at least one edge region of the lid (2), preferably extending linearly, on the outside of the lid (2) or the outer surface. 5. Method according to claim 4, characterized in that the at least one engagement element (3) is designed as a strip-shaped element with hole-like depressions (5) as transmission elements in the strip-shaped element. 6. Method according to one of claims 1 to 3, characterized in that the at least one engagement element (3) is provided with transmission elements in the form of hole-like depressions (5) in the material of the cover (2) or the outer surface itself is formed in the region of a projection (9) of the cover (2) or the outer surface beyond the outer boundaries of the battery housing (1). 7. Method according to claim 6, characterized in that the material of the cover (2) or the outer surface is reinforced in the region of the hole-like depressions (5), preferably reinforced with a correspondingly perforated rail or the like. 8. Method according to one of the preceding claims, characterized in that the edge region of the cover (2) or the outer surface is lifted off the battery housing (1) in a tongue-like manner by the engagement of the lifting device (15) on the at least one engagement element (3). 9. Method according to claim 8, characterized in that the tongue-like raised edge region is mechanically detached from the battery by supplying cold (14) and is lifted from the battery by the force of the lifting device (15) until the cover (2) is substantially completely detached from the battery and can be separated from the battery housing (1). 10. Method according to claim 1, characterized in that at least one edge region of a cover (2) or an outer surface of the closed battery housing (1), preferably under the influence of cold (11, 14), is mechanically separated from the rest of the battery and lifted off like a tongue, a holding device (23) is attached to this tongue-like lifted edge region (16) along the edge on the cover (2), which exerts a force (17) directed away from the battery housing (1) onto the lifted edge region (16) of the cover (2) via a lifting device (15), in the region of the root (20) of the tongue-like lifted edge region (16), further sections of the cover (2) are mechanically detached from the battery by the supply of cold (14) and are lifted off the battery by the force of the lifting device (15) until the cover (2) is essentially completely detached from the battery and from the battery housing (1) is separable. 1 1. Method according to claim 10, characterized in that the holding device (23) is glued to the edge of the lid (2) in the region of the tongue-like raised edge region (16). 12. Method according to claim 10, characterized in that the holding device (23) clamps the lid (2) in the region of the tongue-like raised edge region (16). 13. Method according to claim 12, characterized in that the holding device (23) engages around the lid (2) in the region of the tongue-like raised edge region (16) and clamps it between them. 14. Method according to one of the preceding claims, characterized in that the cold (14) when separating the cover (2) from the interior of the battery is introduced directly into the region of the root (20) of the tongue-like raised edge region (16), preferably directly to the adhesive in the region of the root (20). 15. Method according to one of the preceding claims, characterized in that the cold is introduced from the side of the cover (2) opposite the adhesive connection and the adhesive connection is thereby cooled indirectly. 16. Method according to one of the preceding claims, characterized in that the cover (2) or the outer surface is lifted largely over the entire surface of the battery housing (1) by the simultaneous engagement of the lifting device (15) on preferably several engagement elements (3). 17. Method according to claim 1, characterized in that the at least one surface gripper acting by negative pressure is fixed to the cover (2) or the outer surface as the engagement element (3), preferably a suction gripper, via which the lifting device (15) engages the cover (2) or the outer surface and separates the cover (2) or the outer surface from the battery housing (1). 18. Method according to one of the preceding claims, characterized in that the cover (2) or the outer surface is pre-cooled from outside the battery at least in partial areas (11) before being lifted off from the interior of the battery. 19. Method according to claim 18, characterized in that the lid (2) or the outer surface is cooled by cooling devices arranged on the outside of the lid (2) or the outer surface, in particular cooling elements or cooling pads (11). 20. Method according to one of claims 18 or 19, characterized in that the lid (2) is cooled by cooling nozzles (12) directed towards the outside of the lid (2). 21. Method according to one of claims 18 to 20, characterized in that the cover (2) is formed with a trough-like recess by edges (18) bordering the cover (2) on the outside in order to hold cooling liquid (14) or similar coolant applied, preferably by cooling nozzles (12), on the cover (2). 22. Method according to one of the preceding claims, characterized in that cold (14) is introduced into the area between the cover (2) and the interior of the battery, which cold embrittles the adhesive between the cover (2) and the interior of the battery in a targeted manner in the areas that are separated from one another by mechanical interventions. 23. Method according to one of the preceding claims, characterized in that the mechanical separation between the cover (2) and the interior of the battery is caused by impact- or shock-loadable separation tools (10), in particular by chisels (10). 24. Method according to claim 23, characterized in that the separating tool (10) is moved manually or automatically in the area between the interior of the battery and the cover (2). 25. Method according to one of the preceding claims, characterized in that the mechanical separation between the cover (2) and the interior of the battery is carried out by an impact and/or vibration load, preferably a vibration in the region of the cover, in particular in the region of the tongue-like raised edge region (16) of the cover. 26. Method according to one of the preceding claims, characterized in that a nozzle (12) for introducing the cold (14) into the area between the interior of the battery and the cover (2) is moved together with the separating tool (10). 27. Method according to one of the preceding claims, characterized in that the cold (14) is introduced with the aid of liquid carbon dioxide, preferably with the addition of a cold-stable liquid, via a nozzle (12), preferably into the area between the interior of the battery and the cover (2). 28. Device for making the interior of closed battery housings (1) accessible, in particular of electric vehicles, in particular during recycling and/or repair of the battery, in particular for carrying out the method according to claim 1, characterized in that at least one engagement element (3) is arranged on a cover (2) or on an outer surface of the closed battery housing (1) in the region of the outside of the battery housing (1), and a lifting device (15) engages the at least one engagement element (3) in such a way that a force (17) directed away from the battery housing (1) acts on the cover (2) or the outer surface, which, preferably under the influence of cold (11, 14), mechanically separates the cover (2) or the outer surface from the rest of the battery and lifts it off. 29. Device according to claim 28, characterized in that the at least one engagement element (3) is permanently attached to the cover (2) or the outer surface of the battery housing (1). 30. Device according to one of claims 28 or 29, characterized in that the lifting device (15) and the engagement element (3) have matching transmission elements (5, 6) with which the force (17) of the lifting device (15) directed away from the battery housing (1) is transmitted via the engagement element (3) to the cover (2) or the outer surface. 31. Device according to one of claims 28 to 30, characterized in that the lifting device (15) acts on the at least one engagement element (3) arranged on an edge region of a cover (2) or an outer surface in such a way that the lifting device (15) mechanically separates the edge region from the rest of the battery and lifts it off like a tongue. 32. Device according to one of claims 28 to 31, characterized in that the lifting device (15) engages several engagement elements (3) in such a way that the lifting device (15) lifts the cover (2) or the outer surface largely over the entire surface from the battery housing (1) by the simultaneous engagement. 33. Device according to claim 28, characterized in that a holding device (23) can be fastened to the raised edge region (16) of the cover (2) along the edge-side, tongue-like raised edge, and a lifting device (15) acts on the holding device (23) and thus on the cover (2) in such a way that a force (17) directed away from the battery housing (1) acts on the raised edge region (16) of the cover (2), wherein at least one separating tool (10) engages in the region of the root (20) of the tongue-like raised edge region (16) with the supply of cold (14) and mechanically releases further sections of the cover (2) from the battery, and the force of the lifting device (15) lifts these released sections (16) from the battery until the cover (2) is essentially completely released from the battery and separated from the battery housing (1). 34. Device according to claim 33, characterized in that the holding device (23) has a preferably L-shaped angle, which is fastened with one leg to the previously tongue-like raised edge region of the lid (2) and with the other leg to a lifting device (15). 35. Device according to claim 33, characterized in that the holding device (23) has a clamping device on the one leg which is arranged on the tongue-like raised edge region (16) of the lid (2), with which the tongue-like raised edge region (16) of the lid (2) can be clamped to the holding device (3). 36. Device according to claim 35, characterized in that the clamping device has a rod-like clamping bracket (21) which presses the tongue-like raised edge region (16) of the lid (2) against the holding device (23). 37. Device according to one of the preceding claims, characterized in that the lifting device (15) has a pulling device (25, 26, 27, 28, 29) which pulls away the lifted edge region (16) of the lid (2), preferably obliquely to the lid surface, at least with a component perpendicular to the surface of the lid (2). 38. Device according to claim 37, characterized in that the pulling device (25, 26, 27, 28, 29) has a preferably hydraulically or pneumatically or electrically actuated pull rod (26) which is connected via pulling elements (27, 28, 29) is fixed to the holding device (23) and pulls the lid (2) away with at least one component perpendicular to the surface of the lid (2). 39. Device according to one of claims 37 to 38, characterized in that the lifting device (15) has a winding device which successively winds up the tongue-like lifted edge region (16) of the cover (2) with at least one component of the direction of rotation perpendicular to the surface of the cover (2) and thereby moves along the battery housing (1). 40. Device according to one of the preceding claims, characterized in that at least one separating tool (10) engages in the region of the root (20) of the tongue-like raised edge region, preferably with the supply of cold (14), and mechanically releases further sections of the cover (2) from the battery, and the force of the lifting device (15) lifts these released sections from the battery until the cover (2) is essentially completely released from the battery and separated from the battery housing (1). 41. Device according to one of the preceding claims, characterized in that the separating tool (10) is guided manually and/or automatically and the impact or striking movement of the separating tool (10) is carried out manually and/or automatically. 42. Device according to one of the preceding claims, characterized in that the cutting edges of the separating tool (10), in particular a chisel (10), are designed such that the separating tool (10) is pressed against the interior of the lid (2) and guided along the interior of the lid (2) during mechanical loading. 43. Device according to claim 42, characterized in that the chisel (10) has bevels with different bevel angles. 44. Device according to claim 43, characterized in that the wedge-shaped cutting area of the chisel (10) has a wedge surface intended for contact with the cover (2) of the battery with a wedge angle of substantially 0° and a wedge surface with a wedge angle of more than 0°. 45. Device according to one of the preceding claims, characterized in that the lifting device (15) has a manipulator, preferably automatically movable, which acts on the at least one engagement element (3) and pulls the lid (2) away, preferably obliquely to the lid surface, at least with a component perpendicular to the surface of the lid (2). 46. Device according to claim 45, characterized in that the manipulator has at least one fork- or prong-like arrangement of transmission elements (6) which engage in matching hole-like recesses (5) on the at least one engagement element (3) and hold them. 47. Device according to one of claims 45 or 46, characterized in that the manipulator, in addition to the pulling movement, can carry out a rotational movement (8) with at least one component perpendicular to the surface of the lid (2), with which the lid (2) can additionally be tilted sideways. 48. Device according to one of the preceding claims, characterized in that the device has a closed cabin in which, when the battery housing (1) is opened, an inert atmosphere can be produced by introducing an inert gas, preferably carbon dioxide gas, and displacing the ambient atmosphere from the cabin. 49. Device according to claim 48, characterized in that the cabin has at least one lock for introducing and removing the battery housing 1 to be opened in each case. 50. Battery housing (1) for a battery, in particular a battery for electric vehicles, characterized in that on a cover (2) or on an outer surface of the closed battery housing (1) at least one engagement element (3) is arranged in the region of the outside of the battery housing (1) for a lifting device (15), with which the cover (2) or on the outer surface can be separated from the battery housing (1). 51. Battery housing (1) according to claim 50, characterized in that the at least one engagement element (3) is permanently attached to the cover (2) or the outer surface of the battery housing (1). 52. Battery housing according to one of claims 50 or 51, characterized in that the lifting device (15) and the engagement element (3) fit together. have associated transmission elements (5, 6) with which the force (17) of the lifting device (15) directed away from the battery housing (1) is transmitted via the engagement element (3) to the cover (2) or the outer surface. 53. Battery housing according to one of claims 50 to 52, characterized in that the at least one engagement element (3) is arranged in at least one edge region of the cover (2), preferably extending linearly. 54. Battery housing according to claim 53, characterized in that the at least one engagement element (3) is designed as a strip-shaped element with hole-like depressions (5) in the strip-shaped element. 55. Battery housing according to one of claims 50 to 52, characterized in that the at least one engagement element (3) is formed from hole-like depressions (5) in the material of the cover (2) or the outer surface in the region of a projection (9) of the cover (2) or the outer surface beyond the outer boundaries of the battery housing (1). 56. Battery housing according to claim 55, characterized in that the material of the cover (2) or the outer surface in the region of the hole-like depressions (5) can be reinforced, preferably with a correspondingly perforated rail or the like. 57. Battery housing according to one of claims 50 to 56, characterized in that the cover (2) or the outer surface is designed in a trough-like manner by edges (18) bordering the cover (2) or the outer surface on the outside in order to hold cooling liquid (14) or similar coolant, preferably applied by cooling nozzles (12), on the cover (2) or the outer surface.