FR3157013A1 - ELECTRIC ACCUMULATOR BATTERY - Google Patents

Abstract

The invention relates to an electric accumulator battery (10) comprising: - at least one external terminal (13), - an external container (12), - a stack (11) of a plurality of electric accumulators (14) in said external container (12), each comprising two electrical connection terminals (16), each terminal (16) being connected to at least one terminal (16) of another accumulator, characterized in that the electrical connection of all the terminals (16) located on the same side of the accumulators is achieved by a rectilinear member (20) provided with conductive clamping members (22) cooperating with the terminals (16) of said accumulators (14), which is movable between a disconnection position of the member with the tabs (16) and the external terminal (13), a position of electrical connection with all of said terminals (16) and the external terminal (13). Figure for abstract: Figure 7.

Description

ELECTRIC ACCUMULATOR BATTERY Technical field of the invention

The present invention relates to an electric accumulator battery, in particular intended to be mounted in a motor vehicle.

Technical background

There are various battery pack configurations. According to one known state of the art, electric accumulators are grouped into modules, and the modules are connected to each other within the battery pack. According to another state of the art known as the "cell-to-pack" format, there are no modules, and the electric accumulators are directly stacked in the battery pack via racks in order to obtain the desired on-board energy and voltage.

In the case of a traditional connection of electric accumulators in a pack, the connectors of the electric accumulators are soldered within the pack. The connectors of several cells are soldered together according to an architecture that depends on the desired series or parallel connection type.

Indeed, it is known according to document US-8,486,557-B to propose a battery module comprising a plurality of battery cells or accumulators in the form of sequentially stacked plates, in which each battery module is configured to have a structure in which two or more unit cells are stacked in a state where they are electrically connected to each other. Each of the modules is configured to have a structure in which two or more battery cells are connected in parallel to each other in a state where the battery cells are in close contact with each other. A mechanical connection between electrode terminals of the battery cells and an electrical connection of these terminals is obtained by welding, for example by resistance welding, by laser welding, or by ultrasonic welding with a plurality of welding points.

The battery cells are mounted in metal housings of the module in a state where they are in close contact with each other. The electrical connection between the battery cells can be made in parallel or in series.

When you want to change the battery elements in such a battery to resolve a fault or to replace them, it is necessary, to mechanically extract them from the module, to unsolder the electrode terminals of these battery elements. The presence of welds therefore makes this type of intervention more complicated. In addition, depending on the type of electrical architecture, it is important to pay attention to the voltage present within the battery when opening it, especially in the case of high voltage, because it remains present as long as the electrode terminals of the battery elements are not unsoldered.

Also, one of the aims of the present invention is to provide a battery comprising battery elements or electrical accumulators which can be mechanically separated and electrically disconnected from each other to allow one of them to be replaced.

Another aim of the invention is to ensure safe, rapid and reliable disconnection of the battery during work on one of the electrical accumulators comprising it.

An additional goal is to provide such a battery at a competitive cost and with as simple an architecture as possible.

The invention meets these aims by proposing a battery equipped with a member allowing a mechanical connection and a rapid electrical connection of the terminals of the battery elements or accumulators.

These goals, as well as others that will appear later, are achieved by a battery of electric accumulators comprising:

- at least one external terminal,

- an external tank,

- a longitudinally oriented stack of a plurality of electrical accumulators stacked directly in said external container, each accumulator comprising two electrical connection terminals located transversely on either side of the accumulator, each electrical connection terminal being connected to at least one electrical connection terminal of another accumulator in the stack, characterized in that the electrical connection of all the electrical connection terminals of the accumulators located on the same side is achieved by a rectilinear member which is provided with conductive clamping members capable of cooperating with the electrical connection terminals of said accumulators, said rectilinear member being movable in the external container between a disconnection position in which the conductive clamping members are not in contact with any of the electrical connection terminals and in which said conductive clamping members are not connected to the external terminal of the battery, and a connection position in which the conductive clamping members are simultaneously in electrical contact with all of said electrical connection terminals and connected to the external terminal of the battery.

Preferably, the electric accumulators are in the form of plates and each electrical connection terminal is a tab. The rectilinear member is movable in translation and rotation on itself in the longitudinal direction. This movement can be obtained by two successive rotational and translational movements, or by a helical movement, in particular screwing.

Advantageously, the rectilinear member is a rod, one conductive end of which, which is electrically connected to at least one conductive clamping means, is arranged opposite the external terminal of said battery and the other end of which is connected to an actuating means. The actuating means is preferably arranged outside the external container.

Preferably, at least one accumulator out of two rests in a rack comprising two vertical uprights between which said accumulator is arranged.

According to a first embodiment of the invention, the conductive clamping members are constituted by fins extending substantially transversely from the rod which, when the rod is in the connection position, stress the corresponding tabs by bending them.

Preferably, each tab is clamped against a vertical upright which is arranged against a transverse end of the electric accumulator and which is provided with a first counter-form of length less than that of the corresponding tab.

In this first embodiment of the invention, the ends of the fins, when the rod is in the connection position, urge the tabs to bend them against the first counter-forms.

According to a second embodiment of the invention, each tab is clamped against a vertical upright which is arranged against a transverse end of the electric accumulator and which is provided with at least one wall comprising a second counter-form which extends opposite each tab, and the conductive clamping members are constituted by fingers extending substantially transversely from the rod, each of which comprises an end which, when the rod is in the connection position, urges the corresponding tab to deform it in the corresponding second counter-form.

According to a third embodiment of the invention, every other accumulator rests between two vertical uprights arranged transversely on either side of the accumulator. In this third embodiment, every other accumulator is held longitudinally between two accumulators resting transversely between two vertical uprights, and the conductive clamping members consist of pads extending substantially transversely from the rod which, when the rod is in the connection position, press on the tabs previously folded over each other, two by two, on the first counter-forms.

Advantageously, in these three embodiments of the invention, the vertical uprights are the vertical uprights of a rack.

According to a first configuration of the rectilinear member, the conductive clamping members are all electrically connected together on the rectilinear member. This configuration is particularly suitable for connecting the accumulators in a parallel arrangement.

According to a second configuration of the rectilinear member, two consecutive conductive clamping members are electrically connected two by two on the rectilinear member. This configuration is particularly suitable for connecting accumulators in a series assembly.

Alternatively, the electric accumulators could be prismatic cells, blade batteries or cylindrical cells with rigid electrical connection terminals.

The invention also relates to a method for connecting the tabs of the accumulators of a battery of the type described above, characterized in that it comprises at least one step of moving the rectilinear member consisting of pivoting the rectilinear member around the longitudinal direction and moving the rectilinear member along the longitudinal direction in contact with the tabs.

According to a particular embodiment of this method more particularly associated with the third embodiment of the invention, the method comprises, prior to the step of moving the rectilinear member, a step of folding the tabs onto each other, two by two, on the first counter-forms.

Brief description of the figures

Other characteristics and advantages of the invention will appear during the reading of the detailed description which follows for the understanding of which reference will be made to the appended drawings described briefly below.

There FIG. 1 schematically represents in top view the end of a battery according to a first embodiment, in the disconnected position.

There FIG. 2 is a perspective view of a conductive clamping member according to this first embodiment.

There FIG. 3 corresponds to the FIG. 1 when the conductive clamping members come into contact with the tabs of the accumulators.

There FIG. 4 schematically represents in top view the battery of the FIG. 1 in connected position.

There FIG. 5 is a perspective view of an accumulator support rack.

There FIG. 6 schematically represents in top view the end of a battery according to a second embodiment, in the disconnected position.

There FIG. 7 schematically represents a top view of the battery according to this second embodiment, in the connected position.

There FIG. 8 schematically represents in top view the end of a battery according to a third embodiment, in the disconnected position.

There FIG. 9 schematically represents a top view of a battery according to this third embodiment, in the connected position.

There FIG. 10 is a schematic plan view of a second configuration of a rectilinear member associated with a series connection of the accumulators.

There FIG. 11 is a block diagram illustrating a method of connecting the tabs of the accumulators of a battery according to the invention.

There FIG. 12 is a block diagram illustrating a particular mode of the connection process of the FIG. 11 .

Detailed description of the invention

An electric accumulator battery according to the present invention comprises, in a known manner, an external container 12. The external container 12 is shown schematically in FIG. 1 by a wall. At least one external terminal 13 (and preferably two) protrudes outside the external container 12.

Such a battery according to the invention is known by the English acronym of “cell-to-pack” type battery. It comprises the external container 12 and a plurality of electric accumulators 14 which are, in a non-limiting manner of the invention, in the form of plates. The electric accumulators 14 are stacked longitudinally in a longitudinal direction L directly in this external container 12.

Each electric accumulator 14 extends in a plane orthogonal to the longitudinal direction L. Each electric accumulator 14, as shown in FIGS. 1 and 3 to 9, comprises two electrical connection terminals 16 in the form of tabs located transversely on either side of the accumulator 14, each tab 16 being electrically connected with at least one tab 16 of another accumulator 14 of the stack 11.

In the remainder of this description, the embodiment described here relates to plate-shaped accumulators 14 comprising electrical connection terminals in the form of tabs 16, but it will be understood that this configuration is not limiting of the invention and that the latter can be applied to electrical accumulators made up of prismatic cells, blade batteries or cylindrical cells whose electrical connection terminals are rigid.

In the example described here, each plate-shaped accumulator 14 rests in a rack 15 comprising two vertical uprights 18a and 18b against which the transverse ends of the accumulator are arranged. The electrical connection of all the tabs 16 located on the same side of the accumulator is necessary to obtain the total voltage required by the battery.

Conventionally, a mechanical connection between the tabs 16 of the accumulators 14 and an electrical connection of these tabs 16 is obtained by welding, for example by resistance welding, by laser welding, or by ultrasonic welding with several welding points.

When you want to change the accumulators to resolve a breakdown or to replace them, it is necessary, to mechanically extract them from the battery, to unsolder the tabs 16. The presence of welds therefore makes this type of intervention more complicated. In addition, depending on the type of electrical architecture, it is important to pay attention to the voltage present within the battery when opening it, especially in the case of high voltage, because it remains present as long as the tabs 16 are not unsoldered.

The invention overcomes this drawback by proposing a mechanical connection and a rapid connection of the tabs 16.

For this purpose, in accordance with the invention, the electrical connection of all the tabs 16 of the accumulators 14 located on the same side is carried out simultaneously by a rectilinear member 20 which is provided with conductive clamping members 22 capable of cooperating with the tabs 16 of said accumulators 14. The rectilinear member 20 is movable in the external container 12 between a disconnection position, shown in Figures 1, 6, and 8 in which the conductive clamping members 22 are not in contact with any of the tabs 16 and in which said conductive clamping members 22 are not connected with the external terminal 13 of the battery 10, and a connection position, shown in Figures 4, 7 and 9 in which the conductive clamping members 22 are simultaneously in electrical contact with all the tabs 16 and connected with the external terminal 13 of the battery.

For this purpose, the rectilinear member 20 is movable in translation and in rotation on itself in the longitudinal direction L. Without limiting the invention, the translation and rotation movements can be independent and successive, or else combined in a helical movement of the member 20, obtained for example by screwing.

More particularly, the rectilinear member is a rod 20 of which a conductive end 20a, which is electrically connected to at least one conductive clamping member 22, is arranged opposite the external terminal 13 of the battery and of which the other end 13b is connected to an actuating means, which has not been shown here.

Advantageously, the actuating means is located outside the container 12. Thus, it is possible to connect or disconnect the electrical accumulators 14 from the outside when the container 12 is closed. This makes it possible to avoid exposing an operator to electrical risks.

The electrical connection of the conductive end to one or more conductive clamping members 22 can be achieved by conductors internal to the rod 20 or by the material of the rod 20, itself conductive.

According to a first configuration of the rod 20 which has been shown in figures 1 to 7, the conductive clamping members 22 are all electrically connected together on the rectilinear member 20. This configuration is particularly suitable for a parallel connection of the accumulators 14.

According to a second configuration of the rod 20 which has been shown in the FIG. 10 , two consecutive conductive clamping members 22 are electrically connected two by two on the rectilinear member 20, for example by tracks 23 arranged on the rod 20, which is for its part coated with an electrical insulator. This configuration is particularly suitable for a series connection of the accumulators 14.

According to a first embodiment of the present invention, as shown in Figures 1 to 4, one of the ends 20a of the rod 20 is opposite the external terminal 13 of the battery. Its other end 20b is connected to an actuating means (not shown in the figures).

In this first embodiment, the conductive clamping means 22 secured to the rod 20 are constituted by fins 22 in the shape of a substantially angular sector of a circle, as illustrated more precisely by FIG. 2 , which extend transversely in a direction T relative to the longitudinal direction L. There are, of course, as many fins 22 as there are tabs 16.

As shown in the FIG. 1 , in the disconnected position, the end 20a of the rod 20 is not in contact with the corresponding external terminal 13 of the battery and the fins 22 are not in contact with the tabs 16: in this position of the rod 20, the accumulators 14 are disconnected and therefore it is possible to work on one or other of these accumulators without danger, and in particular to extract them perpendicular to the plane of the FIG. 1 .

By imparting to the rod 20 by the actuating means a translational and rotational movement on itself, the latter moves in the longitudinal direction L until it is connected to the external terminal 13 and the fins 22 come into contact with the tabs 16 by folding them back as shown successively in figures 3 and 4. The translational and rotational movements can be independent or obtained by a helical movement imparted to the rod 20, in particular by screwing it into a thread (not shown) of the external container 12.

In a simple embodiment of the invention, the tabs 16 could be only slightly bent by the fins 20 as shown in FIG. 3 .

However, preferably, each vertical upright 18a, 18b of the rack 15 comprises a counter-form 24 against which each tab 16 is folded by one end 22a of the corresponding fin 22. Thus, the FIG. 3 represents a partial folding of the tabs 16, while the final folding is obtained at the FIG. 4 .

The counter-forms 24 are, in this embodiment, shorter in the transverse direction T than the tabs 16, so that the latter can be folded against them.

The end 22a of each fin 22 then transversely clamps the folded part of the corresponding tongue 16 against the associated counter-form 24.

The end 22a of the fin 22 has a flattened profile. This flattened part makes it possible to hold the fin 22 stably in its clamping position of the corresponding fin 22.

The tabs 16 in this embodiment can be made of an elastic material. It will be understood that, by imparting an inverse movement to the rod 20, the latter disconnects from the external terminal 13 and the fins 22 no longer press on the corresponding tabs 16. These return to a position parallel to each other: all the accumulators 14 of the stack 11 are therefore disconnected since they are no longer electrically connected by the rod 20.

Alternatively, the tabs 16 in this embodiment may be made of a deformable material. By imparting a reverse movement to the rod 20, the latter disconnects from the external terminal 13 and the fins 22 no longer press on the corresponding tabs 16. These remain folded but are disconnected since they are no longer electrically connected by the rod 20.

This configuration does not prevent the extraction of accumulators 14.

Thus, as illustrated by the FIG. 11 , a method of connecting the tabs 16 of the accumulators 14 of a battery 10 of the type described previously comprises a single step ET1 of moving the rectilinear member 20 consisting of pivoting the rectilinear member 20 around the longitudinal direction L and moving the rectilinear member 20 along the longitudinal direction L in contact with the tabs 16. Thus, all the tabs 16 located on the same side of the stack 11 are simultaneously connected to their respective fins 22.

According to a second embodiment which has been shown in figures 6 and 7, the vertical uprights 18a of each rack 15 are provided with at least one wall 26 comprising a second counter-form 28 which extends opposite each tongue 16, and the conductive clamping members are constituted by fingers 22 extending substantially transversely from the rod 20, each of which has an end 22b substantially complementary to the second counter-form 28. There are as many fingers 22 as there are tongues 16.

As shown in the FIG. 6 , the end 20a of the rod 20, provided with the fingers 22, is disconnected from the external terminal 13: in this so-called disconnection position, none of the fingers 22 is in relation with a tab 16.

By imparting to the rod 20 by the actuating means a translational and rotational movement on itself, the latter advances until it is connected to the external terminal 13 and the ends 22b of the fingers 22, as shown in FIG. 7 , come to urge the corresponding tabs 16 to deform them in the corresponding second counter-forms 28. The tabs 16 are here clamped longitudinally against the corresponding counter-forms 28.

In this embodiment, the tabs can be made of an elastic material and in this case the deformation is reversible, or they can be made of a non-elastic material, the deformation then being plastic without this being detrimental to the extraction of the accumulators 14 since the extraction is carried out in a plane perpendicular to the plane of the FIG. 7 .

By imparting an inverse movement to the rod 20, the latter disconnects from the external terminal 13 and the fingers 22 not only no longer press on the corresponding tabs 16, but are no longer in contact with them: all the accumulators 14 of the stack 11 are therefore disconnected from the rod 20, and are therefore all disconnected from each other.

Figures 8 and 9 relate to a third embodiment of the present invention. In this example, one accumulator 14 out of two rests transversely in a rack 15 between two vertical uprights 18a, 18b of this rack. One accumulator 14 out of two is held longitudinally between two immediately adjacent accumulators 14 resting in a corresponding rack 15. The vertical uprights 18a, 18b of the rack 15 comprise the first counter-forms 24 of a length less than that of the tabs 16. The conductive clamping members 22 are constituted by studs 22 extending substantially transversely from the rod 20 which, when the rod 20 is in the connection position, press on the tabs 16 previously folded one on the other, two by two, on the first counter-forms 24. The rod 20 is provided with studs 22: there are as many studs 22 as there are pairs of tabs 16.

Thus, as illustrated by the FIG. 12 , a method of connecting the tabs 16 of the accumulators 14 of a battery 10 of the type described previously is substantially analogous to the method described previously, but comprises, prior to step ET1 of moving the rectilinear member 20, a step ET0 of folding the tabs 16 onto each other, two by two, on the first counter-forms 24.

As shown in the FIG. 8 , the end 20a of the rod 20 provided with the pads 22 is disconnected from the external terminal 13: in this so-called disconnection position, none of the pads 22 is in relation with a tab 16.

As shown in the FIG. 9 , by printing on the rod 20 by the actuating means first a translation movement, the latter advances until it connects to the external terminal 13, then a rotation movement on itself the pads 22 come simultaneously into contact with the tabs 16 already folded one on the other, two by two, by applying them against the counter-form 24.

By imparting a reverse movement to the rod 20, it disconnects from the external terminal 13 and the pads 20 not only no longer press on the corresponding tabs 16, but are no longer in contact with them: all the accumulators 14 of the stack 11 are therefore simultaneously disconnected. The tabs 16 remain folded over each other, two by two.

In a variant of this third embodiment, the racks 15 whose vertical uprights 18a, 18b do not include counter-forms, can be removed: the corresponding accumulators 14 are then held in position by the stacking of all the accumulators 14.

The connection system which is the subject of the invention can also be implemented to connect electric accumulators having electrical connection terminals other than tabs, that is to say rigid electrical connection terminals such as those which equip prismatic cells, blade batteries or cylindrical cells. In this case, the rectilinear member can only be mobile in rotation.

In this case, too, the conductive clamping members do not deform the connection terminals.

A battery 10 according to the present invention allows its accumulators 14 to be connected in a simple and efficient manner and is particularly intended to equip motor vehicles for which reduced maintenance times are required.

Claims (13)

Battery (10) of electric accumulators comprising:
- at least one external terminal (13),
- an external tray (12),
- a stack (11) in longitudinal direction of a plurality of electrical accumulators (14) stacked directly in said external container (12), each accumulator (14) comprising two electrical connection terminals (16) located transversely on either side of the accumulator (14), each electrical connection terminal (16) being connected to at least one electrical connection terminal (16) of another accumulator in the stack (11), characterized in that the electrical connection of all the electrical connection terminals (16) of the accumulators (14) located on the same side is achieved by a rectilinear member (20) which is provided with conductive clamping members (22) capable of cooperating with the electrical connection terminals (16) of said accumulators (14), said rectilinear member (20) being movable in the external container (12) between a disconnection position in which the conductive clamping members (22) are not in contact with any of the terminals electrical connection (16) and in which said conductive clamping members (22) are not connected with the external terminal (13) of the battery (10), and a connection position in which the conductive clamping members (22) are simultaneously in electrical contact with all of said electrical connection terminals (16) and connected with the external terminal (13) of the battery. Battery (10) according to claim 1, characterized in that:
- the electric accumulators (14) are in the form of plates and each electrical connection terminal is a tab (16),
- the rectilinear member (20) is movable in translation and in rotation on itself in the longitudinal direction (L). Battery (10) according to one of claims 1 or 2, characterized in that the rectilinear member (20) is a rod of which one conductive end (20a), which is electrically connected to at least one conductive clamping member (22), is arranged opposite the external terminal (13) of said battery (10) and of which the other end (20b) is connected to an actuating means. Battery (10) according to claim 3, characterized in that the conductive clamping members (22) are constituted by fins extending substantially transversely from the rod (20) which, when the rod (20) is in the connection position, stress the corresponding tabs (16) by bending them. Battery (10) according to claim 1, characterized in that each tab (16) is clamped against a vertical upright (18a, 18b) which is arranged against a transverse end of the electric accumulator (14) and which is provided with a first counter-form (24) of length less than that of the corresponding tab (16). Battery (10) according to claim 5 taken in combination with claim 4, characterized in that ends (22a) of the fins (22), when the rod (20) is in the connection position, urge the tabs (16) to bend them against the first counter-forms (24). Battery (10) according to claim 3, characterized in that each tab (16) is clamped against a vertical upright (18a, 18b) which is arranged against a transverse end of the electric accumulator (14) and which is provided with at least one wall (26) comprising a second counter-form (28) which extends opposite each tab (16), and in that the conductive clamping members (22) are constituted by fingers extending substantially transversely from the rod (20), each of which has an end (22b) which, when the rod (20) is in the connection position, urges the corresponding tab (16) to deform it in the corresponding second counter-form (28). Battery (10) according to claim 5 taken in combination with claim 3, characterized in that:
- one accumulator (14) out of two rests between two vertical uprights (18a, 18b) which are arranged transversely on either side of the accumulator (14),
- one accumulator (14) out of two is held longitudinally between two accumulators (14) resting transversely between two vertical uprights (18a, 18b), and
- the conductive clamping members (22) are constituted by pads (22) extending substantially transversely from the rod (20) which, when the rod (20) is in the connection position, press on the tabs (16) previously folded over each other, two by two, on the first counter-forms (24). Battery (10) according to one of the preceding claims, characterized in that the conductive clamping members (22) are all electrically connected together on the rectilinear member (20). Battery (10) according to one of the preceding claims, characterized in that two consecutive conductive clamping members (22) are electrically connected two by two to the rectilinear member (20). Battery (10) according to claim 1, characterized in that the electrical accumulators (14) are prismatic cells, blade batteries or cylindrical cells whose electrical connection terminals (16) are rigid. Method for connecting the tabs (16) of the accumulators (14) of a battery (10) according to claim 1, characterized in that it comprises at least one step (ET1) of moving the rectilinear member (20) consisting of pivoting the rectilinear member (20) around the longitudinal direction (L) and moving the rectilinear member (20) in the longitudinal direction in contact with the tabs (16). Method for connecting the tabs (16) of the accumulators (14) of a battery according to claim 8, characterized in that it comprises, prior to the step (ET1) of moving the rectilinear member, a step (ET0) of folding the tabs (16) one on top of the other, two by two, on the first counter-forms (24).