WO2025163039A1 - Sealing cover for a container accommodating battery modules, and associated system and method - Google Patents

Abstract

The invention relates to a cover (90) comprising a housing (92) that opens via a main opening (96) and a wall (102) opposite the main opening (96) that defines a gas discharge grating (97) extending between a lower point (120) and an upper point (118). The housing (92) contains at least one baffle (100). The baffle (100) comprises a vertical region (130) extending facing the grating (97) up to an upper edge (134) located above the upper point (118), and an inclined region (132) inclined downwards connecting the vertical region (130) to the wall (102). The housing (92) has a lower wall (104) connected to the wall (102), under the gas discharge grating (97), the lower wall (104) defining at least one through-opening (122) for discharging the liquid out of the housing (92).

Description

DESCRIPTION

TITLE: Sealing cover for a container receiving battery modules, associated system and method

The present invention relates to a sealing cover, configured to cover a pressure relief valve outlet of a container receiving battery modules, the cover comprising a housing defining an internal volume opening through a main opening intended to be placed opposite the valve outlet, the housing having a wall opposite the main opening defining a gas evacuation grid having a plurality of through holes, the gas evacuation grid extending between at least one lower point and at least one upper point, the housing containing at least one baffle.

The container is, for example, a transport container or an electrical cabinet (or “cabinet”).

Conventionally, it is known to build an electrical power storage system by placing, in a standard parallelepiped container, battery modules and an electrical and thermal management unit for the modules. This storage system is easily movable, particularly by road, rail or sea transport.

The structure of the container holding the battery modules generally includes a floor, peripheral walls projecting from the floor, and a roof that closes the interior volume containing the battery modules. The peripheral walls are equipped with doors that allow access to the interior volume when necessary.

Such storage systems contain numerous battery modules themselves containing elements (basic unit of the battery) or electrochemical cells (e.g. lithium-ion cells), as well as electronic and electrotechnical components.

In some rare cases, these storage systems are susceptible to thermal runaway (TR), which can lead to a fire. It is therefore known to monitor the heating resulting from the use of the battery modules present in the container to detect the onset of thermal runaway.

When thermal runaway is detected in a module, one possible measure is to rapidly inject a neutral gas (e.g. nitrogen) into the volume inside the container. The neutral gas replaces the air in the container, in order to limit the risk of combustion or the spread of combustion.

This is done, for example, by providing a bottle of neutral gas in the interior volume of the container, which is opened upon detection of thermal runaway.

To avoid a significant increase in pressure within the internal volume, it is known to equip the container with a pressure relief valve, configured to open as soon as an overpressure greater than a given threshold, for example of the order of one millibar, is obtained.

This prevents, in particular, triggering mechanical safety opening systems, in particular blast panels, or dislocating the container, in the worst case scenario.

Using such a pressure relief valve improves safety. However, by design, this pressure relief valve opens easily, which facilitates the intrusion of dust and liquids into the container, especially in the event of a sandstorm or heavy rain.

To overcome this problem, it is known to have a sealing cover of the aforementioned type, opposite the pressure relief valve outlet, in order to limit the intrusion of liquid and/or dust.

For example, we know from US 2012/0298330 a cover of the aforementioned type, intended to equip a wall with electrical equipment.

The sealing cover described in US 2012/0298330 is not suitable for providing sufficient protection against several types of liquid and dust projection directions, which can occur when these storage systems are arranged in difficult or even hostile environments.

An aim of the invention is therefore to obtain a sealing cover which can easily be mounted on a container of battery modules, opposite a pressure relief valve outlet, the cover not hindering the evacuation of gases through the pressure relief valve, while preventing unwanted intrusions of liquids and/or dust into the container.

To this end, the invention relates to a cover of the aforementioned type, characterized in that the baffle comprises a vertical region extending opposite the gas discharge grid to an upper edge located above the at least one upper point of the gas discharge grid, and an inclined region connecting the vertical region to the wall opposite the main opening, the inclined region being inclined downwards from the inclined region towards the wall opposite the main opening, the housing having a lower wall connected to the wall opposite the main opening, under the discharge grid gases, the lower wall delimiting at least one through-orifice for evacuating liquid from the housing.

The cover according to the invention may include one or more of the following characteristics, taken in isolation or in any technically possible combination:

- the inclined region connects the vertical region to the wall opposite the main opening, below the lower point of the gas evacuation grid;

- the vertical region has a lower edge, the inclined region connecting the lower edge of the vertical region to the wall opposite the main opening;

- the lower edge of the vertical region is located above at least one lower point of the gas discharge grille;

- the lower wall slopes downwards from the main opening towards the wall opposite the main opening, the lower wall preferably connecting to a lower edge of the wall opposite the main opening;

- at least one through-orifice is located under the baffle, advantageously along the junction between the lower wall and the wall opposite the main opening;

- the cumulative area of the or at least one through-hole is less than the cumulative area of the through-holes of the gas evacuation grid;

- the upper edge of the vertical region has a fold;

- the housing has an upper wall extending between the main opening and the wall opposite the main opening, the upper wall being inclined downward from the main opening towards the wall opposite the main opening;

- the box has two side walls connecting the upper wall, the lower wall, and the wall opposite the main opening, the side walls laterally closing the box;

- the baffle extends over the entire width of the housing and is fixed to the side walls;

- it includes a flange for fixing the box to the container projecting outwards around the main opening;

- the baffle is welded onto the housing;

- the box opens exclusively through the main opening, through the through holes in the grid and through at least one through hole.

The invention also relates to an electrical power storage system, comprising:

- a container having at least one peripheral wall defining a gas discharge passage provided with a pressure relief valve having an outlet opening to the outside; - battery modules arranged in the interior volume of the container;

- a sealing cover as defined above, fixed to the peripheral wall around the valve outlet, the wall opposite the main opening extending opposite and away from the valve outlet.

The storage system according to the invention may comprise one or more of the following characteristics, taken in isolation or in any technically possible combination:

- the pressure relief valve comprises a flap which can move between an open gas discharge position and a closed position, the flap possibly being non-tight in the closed position;

- the minimum area of a gas passage section between the valve outlet and the gas discharge grid is greater than 100%, in particular greater than 120% of the area of the valve outlet.

The invention also relates to a method for qualifying a storage system as defined above, comprising at least one of the following steps:

- projection of a jet of liquid inclined downwards into the gas discharge grid, the liquid being deflected by the vertical region of the baffle, without water entering the container through the pressure relief valve;

- projection of a jet of liquid horizontally through the gas discharge grid, the jet of liquid being redirected towards the gas discharge grid, or being partially discharged through the at least one through-orifice opening under the baffle, without water entering the container through the pressure relief valve; and/or

- placing the container in an atmosphere containing dust produced by powder spraying and dust intrusion through the gas exhaust grille and/or through the at least one through-orifice, the dust being deflected by the baffle, without dust entering the container through the pressure relief valve.

The invention will be better understood by reading the following description, given solely by way of example, and made with reference to the appended drawings, in which:

- [Fig.1] Figure 1 is a perspective view of an electrical power storage system according to the invention comprising a container receiving battery modules and a sealing cover according to the invention assembled on the container;

- [Fig.2] Figure 2 is a perspective view from the outside of the sealing cover of the storage system of Figure 1;

- [Fig.3] Figure 3 is a partial sectional view, along a longitudinal plane, illustrating the interior volume defined by the housing of the sealing cover and the baffle contained in the housing; - [Fig.4] Figure 4 is a sectional view along a median axial plane of the sealing cover mounted on a peripheral wall of the container, opposite the pressure relief valve;

- [Fig.5] Figure 5 is a schematic view illustrating a method of qualifying the storage system of Figure 1, comprising projecting a jet of liquid inclined from top to bottom through the grid of the sealing cover;

- [Fig.6] Figure 6 is a view similar to Figure 5, illustrating the projection of a jet of liquid horizontally through the grid;

- [Fig.7] Figure 7 is a view similar to Figure 5 illustrating the intrusion of dust through the grid of the sealing cover.

The term “vertical” and the term “horizontal” are defined below with reference to a container placed on the ground on a horizontal surface.

The term "vertical" is generally understood as having a maximum inclination less than or equal to 5°, preferably less than or equal to 2°, relative to a strictly vertical plane. The term "horizontal" is generally understood as having a maximum inclination less than or equal to 5°, preferably less than or equal to 2°, relative to a strictly horizontal plane.

Figure 1 illustrates a first electrical power storage system 10 according to the invention.

The storage system 10 is intended to be moved to a site of use, for example by a road vehicle such as a truck, by a rail vehicle, and/or by a maritime vehicle such as a transport vessel. It is intended to be electrically connected to an electrical energy use network at a site of use and alternately to an electrical energy supply network for its recharging.

The storage system 10 comprises a container 12 delimiting an interior volume 14, and a plurality of battery modules 16 received in the interior volume 14 (only three modules 16 are shown in dotted lines in FIG. 1).

The storage system 10 advantageously comprises a system (not shown) for electrical and thermal management of the battery modules 16 (“Battery Management Module” or “BMM” in English) and a security system 18.

The container 12 is here formed by a transport container. In variants, the storage system 10 comprises a container of another type, such as an electrical cabinet.

In this example, the container contains, for example, between 10 and 150 battery modules 16. It extends along a longitudinal axis A-A'. The battery modules 16 are mounted in series and/or in parallel to deliver to at least two electrical terminals 22 present on the container, an electrical power which can reach for example up to 4MWh for voltages going in particular up to 1500V.

Each battery module 16 comprises a plurality of electrochemical cells, for example received in prismatic or cylindrical inner cases or in flexible pockets. Each electrochemical cell comprises anodes, cathodes and separators, between which electrochemical reactions take place. The electrochemical cells are for example lithium-ion cells.

The battery modules 16 are generally arranged vertically in the form of columns and horizontally in the form of at least one row extending parallel to the longitudinal axis A-A' of the container.

Each row comprises a plurality of columns of battery modules 16, arranged one after the other, parallel to the axis A-A’.

The electrical management system (not shown) is capable of controlling the voltage and intensity delivered by each battery module 16 when supplying electrical power, and the power and intensity of electrical current delivered to each battery module 16 when recharging the battery modules 16.

The electrical terminals 22 are intended to connect to the user network (not shown) for the supply of electrical energy stored in the battery modules 16, and alternately, to an electrical power supply network, for recharging the battery modules 16.

The safety system 18 comprises, for example, sensors for detecting temperature and/or pressure in the interior volume 14, a source of inert gas, for example at least one pressurized bottle containing inert gas, and a control unit, capable of delivering the inert gas into the interior volume 14 from the source of inert gas, upon detection of an increase in temperature, smoke, carbon monoxide and/or pressure greater than a given threshold in the interior volume 14, in particular in one or more battery modules 16.

Inert gas is, for example, nitrogen or argon.

With reference to FIG. 1, the container comprises a self-supporting structure 30, intended to define the interior volume 14, and to allow the joint transport of the battery modules 16, the management system, and the security system 18 to a site of use. With reference to FIG. 1, the structure 30 comprises a floor 32, peripheral walls 36 projecting at the periphery of the floor 32 and a roof 38. The floor 32, the peripheral walls 36 and the roof 38 internally delimit the interior volume 14.

The structure 30 of the container is here of polyhedral shape. In particular, the structure 30 has the shape of a rectangular parallelepiped, extending longitudinally along the longitudinal axis A-A’. The axis A-A’ is horizontal when the container is placed on a horizontal support.

The dimensions of the 30 structure are governed by transport standards.

For example, the container has a length greater than 2 m, in particular between 2.5 m and 15 m, a width greater than 1 m, in particular between 2 m and 4 m and a height greater than 1 m, in particular between 2 m and 4 m.

The height of the container is generally less than its length, taken along the A-A’ axis.

The container is notably a 20-foot container called “High Cube” measuring 6.058 m in length, 2.438 m in width and 2.896 m in height.

It advantageously has lower corners 39 (often called "ISO corners"), which project downwardly from the floor corners 32.

The floor 32 is here flat. With reference to FIG. 1, it defines upwards, an upper flat support surface. The support surface carries the battery modules 16, the management system as well as the security system 18.

The structure of the container 30 further comprises a lower frame for supporting the floor 32. The lower frame comprises at least two longitudinal beams 40 extending on the sides of the container on either side of the axis A-A', parallel to the axis A-A'. The lower frame further comprises a plurality of crosspieces 42 connecting the beams 40 together.

Each beam 40 is here formed from a longitudinal profile, for example of polygonal section, or alternatively, from an IPN.

At least one intermediate cross member extends between the longitudinal beams 40 away from the longitudinal ends of the container.

The roof 38 closes the interior volume 14 upwards. Here, it is provided with blast panels 44, configured to open when a substantial overpressure (for example greater than or equal to 25 mb) appears in the interior volume 14 relative to the exterior.

With reference to Figure 1, the peripheral walls 36 comprise two longitudinal vertical walls 50A, 50B, the longitudinal walls 50A, 50B being arranged vertically, parallel to the axis A-A', on either side of the axis A-A'. The peripheral walls 36 further comprise two transverse vertical walls 52C, 52D, extending perpendicular to the axis A-A', and connecting the longitudinal walls 50A, 50B to each other at the longitudinal ends of the structure 30.

The longitudinal walls 50A, 50B and the transverse walls 52C, 52D delimit two by two corners of the structure 30. They delimit the interior volume 14 towards the outside.

As visible in Figure 1, the longitudinal walls 50A, 50B and possibly the transverse walls 52C, 52D are provided with movable doors 53A, 53B providing access to the interior volume 14 from the outside of the container, and a locking mechanism 53C for the movable doors 53A, 53B.

The structure 30 possibly comprises an internal partition 54 in the interior volume 14, the internal partition 54 delimiting, in the interior volume 14, a compartment 56 for storing the battery modules 16, and separately, a control compartment 58, receiving the management system and the security system 18.

The neutral gas source present in the control compartment 58 is configured to deliver neutral gas throughout the interior volume 14, including the storage compartment 56, upon command from the control unit.

To avoid a rise in pressure likely to trigger the opening of the deflagration panels 44, or even a dislocation of the container, at least one peripheral wall 36 defines, as visible in Figure 4, a passage 70 for evacuating gas from the interior volume 14, provided with a pressure relief valve 72 opening towards the outside of the container 12.

The gas discharge passage 70 extends through the peripheral wall 36 to open into the interior volume 14. In this example, it is for example provided in the transverse wall 52C. It opens inwards into the storage compartment 56, axially opposite the control compartment 58.

The gas discharge passage 70 here extends horizontally, preferably in an upper region of the peripheral wall 36 in the vicinity of the roof 38.

The pressure relief valve 72 is configured to close the gas discharge passage 70 at rest. It is also configured to open when a pressure difference greater than a threshold difference appears between the interior volume 14 and the exterior of the container 12.

The threshold difference is chosen to be lower than the overpressure causing the opening of the deflagration panels 44. It is for example between 0.1 mbar and 10 mbar, in particular between 1 mbar and 10 mbar. In the particular example shown in FIG. 4, the pressure relief valve 72 comprises a jacket 76 inserted in a sealed manner at the periphery of the gas discharge passage 70, a valve 78 movable between a closed rest position and an open gas discharge passage position, and at least one stop 80 for wedging the valve 78 in the closed position.

The jacket 76 delimits an inlet 84 of the pressure relief valve 72 opening into the interior volume 14, an outlet 86 of the pressure relief valve 72 opening towards the outside and an intermediate light 88 connecting the inlet 84 to the outlet 86, in which the valve 78 and each stop 80 are housed.

In this example, the valve 78 is movable in rotation, in particular under the effect of an overpressure greater than the threshold difference present in the interior volume 14, around an axis 82 perpendicular to the axis of the gas discharge passage 70 between the closed position and the open position.

In the open position, the valve 78 has pivoted away from each stop 80. The gas circulation section within the gas discharge passage 70 is then maximum.

On the contrary, in the closed position, the valve 78 is arranged to bear against the or each stop 80. The gas circulation section within the gas discharge passage 70 is then minimal.

In most cases, the valve 78 does not seal the gas discharge passage 70, even in the closed position.

To compensate for a possible lack of sealing of the pressure relief valve 72, the storage system 10 comprises a sealing cover 90 according to the invention, attached to a peripheral wall 36 of the container 12, to cover the outlet 86 of the pressure relief valve 72.

The sealing cover 90 is illustrated by figures 2 to 4. It comprises a hollow housing 92 delimiting an internal volume 94 (see figure 3) opening through a main opening 96 for capturing gases and through a grid 97 for discharging gases, arranged opposite the main opening 96.

The sealing cover 90 further comprises a flange 98 for fixing the housing 92 to the peripheral wall 36, arranged at the periphery of the main opening 96 and an internal baffle 100 for protection against the ingress of liquid and/or dust through the grid 97, fixed to the hollow housing 92 in the internal volume 94.

In this example, the sealing cover 90 is made of metal, for example galvanized steel or stainless steel. Referring to Figures 2 to 4, the housing 92 comprises a vertical wall 102 extending opposite the main opening 96, a lower wall 104, inclined downwardly while moving away from the peripheral wall 36 and an upper wall 106, advantageously inclined downwardly while moving away from the peripheral wall 36.

The housing 92 comprises two side walls 108 connecting the walls 102, 104, 106, on either side of the housing 92, to laterally close the housing 92.

The vertical wall 102 extends vertically between an upper edge 110 advantageously disposed above the valve outlet 86 and a lower edge 112 disposed below the valve outlet 86.

The gas evacuation grid 97 is delimited by the vertical wall 102 which is at least partially perforated. The gas evacuation grid 97 thus has a plurality of holes 114 passing through the vertical wall 102, delimited between them by members 116.

In this example, the gas evacuation grid 97 has an area less than the area of the vertical wall 102. This area is generally greater than the area of the valve outlet 86, in particular greater than or equal to 1.2 times the area of the valve outlet 86.

Each hole 114 has an individual area less than 120 mm ² , in particular between 80 mm ² and 120 mm ² , in particular between 90 mm ² and 110 mm ² . The cumulative area of the holes 114 of the grid is greater than 100%, in particular greater than 120% of the area of the valve outlet 86.

Each hole is, for example, square in outline with a side dimension between 8 mm and 12 mm.

Thus, intrusions of birds or nesting insects such as bees into the internal volume 94 are prevented, while ensuring minimal pressure loss for the evacuation of gases from the valve outlet 86 through the gas evacuation grid 97.

The gas evacuation grid 97 extends vertically between at least one upper point 118, here a horizontal upper edge, and at least one lower point 120, here a horizontal lower edge.

The lower point 120 extends above and away from the lower edge 112, for example at a height greater than 5% of the height of the vertical wall 102, taken between the lower edge 112 and the upper edge 110.

The lower wall 104 here connects a lower edge of the main opening 96 to the lower edge 112 of the vertical wall 102. It slopes downwards between the main opening 96 and the vertical wall 102. The angle of inclination of the lower wall 104 relative to a horizontal plane is for example greater than 3°, in particular greater than 5° and is in particular between 3° and 15°. The lower wall 104 defines, along the lower edge 112 of the vertical wall 102, under the baffle 100, at least one through-orifice 122 for discharging liquid, advantageously, a line of through-orifices 122.

Each through hole 122 passes vertically through the lower wall 104.

In the example shown in Figures 2 to 4, the bottom wall 104 defines a row of through holes 122 arranged side by side along the bottom edge 112.

Each through-orifice 122 has an individual area of less than 120 mm ² , in particular between 80 mm ² and 120 mm ² , in particular between 90 mm ² and 110 mm ² . The cumulative area of the through-orifices 122 is less than 10% of the cumulative area of the through-holes 114 of the gas evacuation grid 97.

These through holes 122 are intended to evacuate excess water and dust, but are not normally intended to evacuate gases coming from the pressure relief valve 72.

Thus, the through-orifices 122 are sized to evacuate any possible accumulation of liquid or dust on the lower wall 104 into the internal volume 94, while preventing the intrusion of birds.

The upper wall 106 is solid. Here, it connects an upper edge of the main opening 96 to the upper edge 110 of the vertical wall 102. It slopes downwards between the main opening 96 and the vertical wall 102. The angle of inclination of the upper wall 106 relative to a horizontal plane is, for example, greater than 3°, in particular greater than 5° and is in particular between 3° and 15°.

The downward inclination of the upper wall 106 by moving away from the peripheral wall 36 limits the accumulation of liquid or solid on the housing 92, limiting the risks of degradation, in particular by corrosion of the housing 92.

Each side wall 108 defines a side edge of the main opening 96. It connects a side edge of the vertical wall 102 to a side edge of the bottom wall 104 and to a side edge of the top wall 106.

Each side wall 108 is here solid to laterally close the internal volume 94 and thus limit its exposure to bad weather and dust.

The fixing flange 98 projects outwardly at the periphery of the main opening 96, downwardly from the bottom wall 104, upwardly from the top wall 106 and laterally from each side wall 108. It defines through holes 124 receiving fixing members (not shown) from the housing 92 to the peripheral wall 36. Thus, when the sealing cover 90 is fixed to the peripheral wall 36, the housing 92 completely covers the valve outlet 86, and the closed peripheral edge of the main opening 96 surrounds the valve outlet 86. The discharge grille 97 on the vertical wall 102 opposite the main opening 96 is advantageously located at least partly opposite the valve outlet 86.

All the gases extracted from the internal volume 14 of the container 12 are therefore forced to enter and travel through the internal volume 94 of the housing 92, before being discharged through the evacuation grid 97.

The internal baffle 100 extends completely into the internal volume 94, opposite the grid 97. With reference to FIGS. 3 and 4, it comprises a vertical region 130 for protection against the intrusion of liquid and dust, arranged away from the vertical wall 102 and a region 132 inclined downwards for connecting the vertical region 130 to the vertical wall 102.

The internal baffle 100 advantageously extends over the entire width of the internal volume 94 of the housing 92 between the side walls 108. The lateral edges of the internal baffle 100, in the vertical region 130 and in the inclined region 132, are assembled on the side walls 108, for example by welding.

The internal baffle 100 further extends above and vertically away from the lower wall 104 over its entire width, in particular above the through-holes 122.

The vertical region 130 is solid. It extends here between a horizontal upper edge 134 and a horizontal lower edge 136 which connects it to the inclined region 132.

The upper edge 134 is arranged over its entire extent above the gas evacuation grid 97. Preferably, the height vertically separating the upper point 118 of the gas evacuation grid 97 from the upper edge 134 of the vertical region is greater than 5% of the height of the gas evacuation grid 97 and is in particular between 5% and 10% of the height of the gas evacuation grid 97.

Thus, the pressure relief valve 72 is protected from liquid splashes or dust ingestion by the mechanical barrier formed by the vertical region 130.

The horizontal lower edge 136 extends opposite the gas evacuation grid 97, above the lower point 120.

Advantageously, to reinforce the mechanical strength of the internal baffle 100, the upper edge 134 has a fold 138 which is here directed towards the main opening 96.

The area measured horizontally at the upper edge 138 between the upper region 130, the vertical wall 102 and the side walls 108 is greater than or equal to 120% to the area of the valve outlet 86, measured vertically and intended for the passage of gases.

The area measured horizontally at the upper edge 138 between the upper region 130, the main opening 96 and the side walls 108 is 120% greater than the area of the valve outlet 86, measured vertically and intended for the passage of gases.

The area measured vertically at the upper edge 134 between the upper region 130, the upper portion 106 and the side walls 108 is 120% greater than the area of the valve outlet 86, measured vertically and intended for the passage of gases.

The vertical region 130 extends in this example substantially halfway between the main opening 96 and the vertical wall 102.

The inclined region 132 extends between the lower edge 136 of the vertical region 130 and the lower point 120 of the gas discharge grid 97. It slopes downwards from the vertical region 130 towards the vertical wall 102. The angle of inclination of the inclined region 132 relative to a horizontal plane is for example greater than 5°, in particular greater than 8°, and is in particular between 5° and 15°.

This angle of inclination is greater than that of the lower wall 104 and that of the upper wall 106.

The inclined region 132 extends above and away from the bottom wall 104. It is positioned above the through-holes 122.

The inclined region 132 here comes from the same material as the vertical region 130.

The internal baffle 100 thus defines, in the internal volume 94, a tortuous path 140 of the gases between the valve outlet 86 and the gas evacuation grid 97.

This path 140 here has an inverted U shape. It has a minimum gas passage section with an area greater than 100%, in particular greater than 120% of the area of the valve outlet 86, taken in projection in a vertical plane.

Thus, despite the protection provided by the internal baffle 100, the gas flow remains significant in the event of evacuation from the interior volume 14 of the container 12, effectively preventing a rise in pressure in the interior volume 14.

The storage system 10, provided with a sealing cover 90 according to the invention, is configured to be qualified in terms of protection against the intrusion of liquids into the interior volume 14 of the container 12 according to the UL50E-3R and UL50E-3S Standards, October 2020 version. It is also configured to be qualified in terms of protection against the intrusion of dust into the interior volume 14 of the container 12 according to the UL50E-3X Standards, October 2020 version and/or IEC 60529:1989 indicating an IP protection index, here validated at IP6X, November 1989 version. With reference to Figure 5, for the implementation of the UL50E-3R Standard, a jet of liquid 150 oriented at 45° downwards is projected onto the vertical wall 102 facing the valve outlet 86.

The liquid jet 150 is preferably projected from a point 152 located away from and above the vertical wall 102. The liquid jet 150 is oriented for example at an angle of between 40° and 50° relative to a horizontal plane.

At least a portion of the liquid projected by the jet 150 enters obliquely into the internal volume 94 through the through holes 114 of the grid 97. This liquid abuts against the vertical region 130 and slides along the inclined region 132 to be evacuated through the through holes 114 of the grid 97. The upper edge 134 of the vertical region 130 being located above the upper point 118 of the grid 97, the liquid remains confined between the vertical region 130 and the vertical wall 102.

Thus, in operation, the sealing cover 90 according to the invention protects the valve outlet 86 from the intrusion of liquids coming from above the cover 90, even if the valve 78 does not close tightly.

Referring to Figure 6, for the implementation of the UL50E-3S Standard, a horizontal jet of liquid 154 is projected onto the vertical wall 102, facing the valve outlet 86.

The liquid jet 154 is preferably projected by a nozzle with a diameter between 20 mm and 30 mm, from a point 156 located at a horizontal distance between 2.5 m and 3.5 m from the vertical wall 102, with a flow rate between 150 l/min and 200 l/min.

At least a portion of the liquid projected by the jet 154 enters horizontally into the internal volume 94 through the through holes 114 of the grid 97. This liquid abuts against the vertical region 130. A portion of the liquid slides along the inclined region 132 to be evacuated through the through holes 114 of the grid 97.

Another portion of the liquid rises along the vertical region 130, passes over the upper edge 134 before descending again along the vertical region 130 opposite the main opening 96 to pass under the inclined region 132. The liquid then drains through the through orifices 122.

The upper edge 134 of the vertical region 130 being located above the upper point 118 of the grid 97, the liquid remains essentially conveyed on either side of the vertical region 130, without reaching the valve outlet 86.

Thus, in operation, the sealing cover 90 according to the invention protects the valve outlet 86 from the intrusion of liquids sweeping the cover 90, for example in the event of strong wind, even if the valve 78 does not close tightly.

Referring to Figure 7, for the implementation of Standard IEC 60529:1989, the container 12 is placed in a chamber. A powder, in particular talc, having a diameter advantageously between 50 pm and 100 pm is sprayed into the chamber creating an atmosphere 160 containing dust opposite the container 12, in particular at the level of the grid 97.

Container 12 is tested under operating conditions, including with ventilation switched on.

At least part of the dust present in the atmosphere 160 enters horizontally into the internal volume 94 through the through holes 114 of the grid 97, in particular under the effect of the suction generated at the valve outlet 86 by the ventilation within the container 12.

The dust strikes the vertical region 130 and falls back along the inclined region 132.

A dust stream rises along the vertical region 130, passes over the upper edge 134, before descending again along the vertical region 130.

Furthermore, another flow of dust enters the internal volume 94 via the through orifices 122. The meeting of the two flows creates a disturbance (for example a vortex) opposite the valve outlet 84 and thus contains the dust which may have passed behind the vertical region 130 by preventing it from being sucked through the valve outlet 86.

The upper edge 134 of the vertical region 130 being located above the upper point 118 of the grid 97, and the through orifices 122 being located below the inclined region 132, the dust flow remains essentially conveyed on either side of the vertical region 130, without reaching the valve outlet 86.

Thus, in operation, the sealing cover 90 according to the invention protects the valve outlet 86 from the intrusion of dust sweeping the cover 90, for example in the event of a sandstorm, even if the valve 78 does not close tightly.

The sealing cover thus allows the container 12 to meet the IP6X criterion according to Standard IEC 60529: 1989, i.e. no dust enters it through the valve outlet 86.

In operation, the sealing cover 90 of the storage system 10 according to the invention does not disrupt the security provided by the pressure relief valve 72.

At rest, when no significant heating is observed on the battery modules 16, the valve of the pressure relief valve 72 is in the closed position, resting on the or each stop 80.

If thermal runaway is detected by the sensors present within the interior volume 14, the control unit of the safety system delivers inert gas into the interior volume 14 from the inert gas source. The pressure in the interior volume then increases. The pressure relief valve 72 opens when a pressure difference greater than a threshold difference appears between the interior volume 14 and the exterior of the container 12. In the example of FIG. 4, the valve 78 pivots around its rotation axis 82, releasing the passage of gases through the valve outlet 86.

The gases then travel along the tortuous path 140 towards the grid 97 to be evacuated through the through holes 114.

Thus, the sealing cover 90 according to the invention is particularly effective in preventing liquid intrusions into the container 12, in particular within the meaning of Standards UL50E-3R and UL50E-3S, and also dust intrusions, in particular within the meaning of Standards UL50E-3X version of October 2020 and IEC 60529:1989, in particular by respecting the IP6X index within the container.

The slopes of the upper wall 106, the lower wall 104 and the presence of the inclined region 132 within the baffle 100 also prevent the accumulation of liquid on or within the sealing cover, preventing the valve outlet 86 from being obstructed by ice or snow. This makes it possible to comply with the freezing test within the meaning of Standard UL50E-3S, October 2020 version.

The sealing cover 90 is easily assembled on the peripheral wall 36 of a container 12, in particular a transport container, to cover an outlet 86 of a pressure relief valve 72. It does not disturb the reliability of the operation of the pressure relief valve 72.

In one variant (not shown), the container is an electrical cabinet which comprises a floor, side walls and a top wall which delimit the interior volume 14 containing the battery modules 16.

The cabinet is generally made of metal and grounded. It is taller than it is wide. It is advantageously configured to obstruct fire and is generally equipped with a cooling system, including ventilation. The electrical cabinet has at least one door equipped with a lock to limit access to people.

As a further variant, the pressure relief valve 72 has a structure different from that described above and shown in the figures.

Claims

1. Sealing cover (90), configured to cover an outlet (86) of a pressure relief valve (72) of a container (12) receiving battery modules (16), the cover (90) comprising a housing (92) defining an internal volume (94) opening through a main opening (96) intended to be placed opposite the valve outlet (86), the housing (92) having a wall (102) opposite the main opening (96) defining a gas evacuation grid (97) having a plurality of through holes (114), the gas evacuation grid (97) extending between at least one lower point (120) and at least one upper point (118), the housing (92) containing at least one baffle (100), characterized in that the baffle (100) comprises a vertical region (130) extending opposite the gas evacuation grid (97) up to an upper edge (134) located above the at least one upper point (118) of the gas discharge grid (97), and an inclined region (132) connecting the vertical region (130) to the wall (102) opposite the main opening (96), the inclined region (132) being inclined downwardly from the inclined region (132) towards the wall (102) opposite the main opening (96), the housing (92) having a lower wall (104) connected to the wall (102) opposite the main opening (96), under the gas discharge grid (97), the lower wall (104) delimiting at least one through-orifice (122) for discharging liquid from the housing (92). 2. Cover (90) according to claim 1, in which the vertical region (130) has a lower edge (136), the inclined region (132) connecting the lower edge (136) of the vertical region (130) to the wall (102) opposite the main opening (96). 3. Cover (90) according to claim 2, wherein the lower edge (136) of the vertical region (130) is located above the at least one lower point (120) of the gas evacuation grid (97). 4. A lid (90) according to any preceding claim, wherein the bottom wall (104) slopes downwardly from the main opening (96) towards the wall (102) opposite the main opening (96), the bottom wall (104) preferably connecting to a lower edge (112) of the wall (102) opposite the main opening (96). 5. Cover (90) according to any one of the preceding claims, in which the at least one through-orifice (122) is located under the baffle (100), advantageously along the junction between the lower wall (104) and the wall (102) opposite the main opening (96). 6. Cover (90) according to any one of the preceding claims, in which the cumulative area of the or at least one through-hole (122) is less than the cumulative area of the through-holes (114) of the gas evacuation grid (97). 7. Cover (90) according to any one of the preceding claims, in which the upper edge (134) of the vertical region (130) has a fold (138). 8. A cover (90) according to any preceding claim, wherein the housing (92) has an upper wall (106) extending between the main opening (96) and the wall (102) opposite the main opening (96), the upper wall (106) being inclined downwardly from the main opening (96) towards the wall (102) opposite the main opening (96). 9. Cover (90) according to claim 8, in which the housing (92) has two side walls (108) connecting the upper wall (106), the lower wall (104), and the wall (102) opposite the main opening (96), the side walls (108) laterally closing the housing (92). 10. Cover (90) according to claim 9, in which the baffle (100) extends over the entire width of the housing (92) while being fixed to the side walls (108). 11. Lid (90) according to any one of the preceding claims, comprising a fixing flange (98) of the housing (92) to the container (12) projecting outwards around the main opening (96). 12. Cover (90) according to any one of the preceding claims, in which the baffle (100) is welded to the housing (92). 13. System (10) for storing electrical power, comprising: a container (12) having at least one peripheral wall (36) defining a gas discharge passage (70) provided with a pressure relief valve (72) having an outlet (86) opening outwards; battery modules (16) arranged in the interior volume (14) of the container (12); a sealing cover (90) according to any one of the preceding claims, fixed on the peripheral wall (36) around the valve outlet (86), the wall (102) opposite the main opening (96) extending opposite and away from the valve outlet (86). 14. System (10) according to claim 13, in which the pressure relief valve (72) comprises a flap (78) movable between an open gas discharge position and a closed position, the flap (78) possibly being non-tight in the closed position. 15. System (10) according to any one of claims 13 or 14, wherein the minimum area of a gas passage section between the valve outlet (86) and the gas discharge grid (97) is greater than 100%, in particular greater than 120% of the area of the valve outlet (86). 16. A method for qualifying a system (10) according to any one of claims 13 to 15, comprising at least one of the following steps: projecting a jet of liquid (150) inclined downwards into the gas discharge grid (97), the liquid being deflected by the vertical region (130) of the baffle (100), without water entering the container (12) through the pressure relief valve (72); projecting a jet of liquid (154) horizontally through the gas discharge grid (97), the jet of liquid (154) being redirected towards the gas discharge grid (97), or being partially evacuated through the at least one through-orifice (122) opening under the baffle (100), without water entering the container (12) through the pressure relief valve (72); and/or placing the container (12) in an atmosphere (160) containing dust produced by powder spraying and dust intrusion through the gas evacuation grid (97) and/or through the at least one through-orifice (122), the dust being deflected by the baffle (100), without dust entering the container (12) through the pressure relief valve (72).