Electrical energy storage system

Abstract

Electrical energy storage assembly. Assembly (20) of electrical energy storage comprising: - a plurality of pocket-type electrical storage cells (50), each pocket-type cell (50) comprising: - a cathode and an anode enclosed in a pocket (54), - a cathode electrical connection leg (55) electrically coupled to the cathode, and - an anodic electrical connection leg (56) electrically coupled to the anode, the anodic and cathodic electrical connection legs (55, 56) protruding from the pocket (54), - a cathode connector (57) and an anodic connector (58) for paralleling the cells, the cathode legs (55) being folded over each cathode connector (57) and the anodic legs (56) being folded over each anodic connector (58), so as to electrically connect the cathodes of the pocket-type cells (50) on the one hand and the anodes of the cells on the other. pocket (50) on the other hand.Figure for the summary: Fig 24.

Description

Title of the invention: Electrical energy storage assembly Technical field

[0001] The present invention relates to electrical energy storage devices comprising rows of accumulator modules, and more particularly but not exclusively to containerized stationary storage devices.

[0002] The invention also relates to an electric accumulator module used in such storage devices, as well as a stack of electric accumulator cells constituting the module, an electrical energy storage assembly making it possible to form the stack, a bus bar, an interconnection assembly, and finally a pack comprising several modules. Prior art

[0003] The development of intermittent renewable energies such as photovoltaic or wind energy is accompanied by the need to benefit from stationary storage devices making it possible to store energy during production periods and to restore it outside of these periods.

[0004] To meet this need, storage devices have been proposed comprising maritime standard containers, in which racks of accumulator modules, a cold production system and a power conversion system are arranged.

[0005] The racks are most often made from modules identical to those developed for the automotive industry, and have frames on which the modules are inserted, spaced vertically apart from each other.

[0006] Modules developed for the automotive industry are generally complex, because the mechanical structure used to hold the cells must withstand the vibrations and accelerations encountered on a vehicle. However, strengthening the mechanical structure of these modules comes at the expense of storage capacity.

[0007] Furthermore, during use of the module, the electric accumulator cells contained in the module swell and deform. These deformations cause pressures inside the module, which can cause expansion of the module and thus reduce its service life. The service life of the accumulator cells is in fact dependent on their correct compression.

[0008] Application WO 2021 / 135955 relates to an electric accumulator module comprising a row of prismatic accumulator cells arranged between two end cheeks held tight by a metal strip and a plastic strip, which can be superimposed to form an overall cable. The choice of two strips of different materials with different tensile strengths and elastic moduli helps improve the reliability of connections within the cell arrangement while managing internal pressures within the module due to cell aging.

[0009] Application WO 2021 / 052005 describes an electric accumulator module comprising a row of prismatic accumulator cells arranged between two end cheeks and side plates clamped by strips. The interlocking of the plates together and their arrangement make it possible to release the internal pressures in the module during its use.

[0010] Beyond the problems of module compression, the connection of accumulator cells, particularly pocket-type cells, to each other is the subject of much research with the aim of achieving gains in compactness and energy density while ensuring good connection of the cells.

[0011] Application US 2019 / 0097201 proposes soldering together the electrical connection tabs connected to electrodes of opposite polarity of two contiguous pouch-type cells to form elementary battery units in series. These battery units are then connected in series within the module.

[0012] There is thus an interest in increasing the on-board storage capacity in electrical energy storage containers, facilitating their manufacture and maintenance and improving their safety and reliability. There are still needs to ensure the correct connection of the cells within the modules, facilitate their assembly and guarantee a good service life.

[0013] The invention aims to meet all or part of these needs. Summary of the invention Electrical energy storage system

[0014] According to a first of its aspects, the invention relates to an electrical energy storage assembly comprising: - a plurality of pocket-type electric accumulator cells, each pocket-type cell comprising:

[0015] - a cathode and an anode enclosed in a pocket, - an electrical connection cathode lug electrically coupled to the cathode, and - an anode electrical connection tab electrically coupled to the anode, the anode and cathode electrical connection tabs protruding from the pocket,

[0016] - a cathode connector and an anode connector for paralleling the cells of the plurality of cells of the assembly, the cathode and anode connectors each having at least one flattened portion, the cathode legs each being folded onto the cathode connector and the anode legs each being folded onto the anode connector, so as to electrically connect together the cathodes of the pocket-type cells on the one hand and the anodes of the pocket-type cells on the other hand.

[0017] By "electric accumulator cell" is meant an electrical energy storage cell.

[0018] By "pocket type" is meant that the pocket type cell of the assembly according to the invention corresponds to a cell designated under the name "pouch" in English, its shape being reminiscent of a pocket or a sachet. A pocket type cell may comprise an anode, a cathode, a permeable membrane separating the anode and the cathode, and a pocket.

[0019] The pocket may take the form of a bag closed around its entire circumference with the exception of one or two slits through which the anode and cathode connection tabs, respectively electrically coupled to the anode and the cathode, protrude from the pocket.

[0020] By "enclosed in a pocket" is meant that the pocket completely surrounds the anode and the cathode with the exception of the slots allowing the passage of the cathode and anode electrical connection tabs.

[0021] The pouch may be flexible. The pouch may take the form of a film.

[0022] The pocket can be made at least partially, in particular partially, in electrically conductive material, especially metal, for example aluminum. The pocket may be provided with an insulating coating.

[0023] The electric accumulator cells of the assembly may use any type of technology, for example Lithium ion, Lithium polymer, Lithium iron phosphate, Lithium metal polymer or Lithium air, among other Lithium-based technologies; the cells may alternatively use other accumulator technologies, other than Lithium-based.

[0024] The assembly may comprise between 1 and 20 pocket-type cells, better between 2 and 10 pocket-type cells, for example four.

[0025] The set may comprise an even number of pocket-type cells, for example two or four. Alternatively, the set may comprise an odd number of pocket-type cells.

[0026] Pocket-type cells may have two opposite main faces connected by an edge. Pocket-type cells may have a generally parallelepiped shape, in particular a rectangular parallelepiped.

[0027] The main faces of the pocket-type cells have a length L, which may be between 400 mm and 600 mm, or even between 450 mm and 550 mm, better still between 500 mm and 550 mm, being for example 514 mm. By length of the face is meant main the largest dimension of the main face.

[0028] The main faces of the pocket-type cells have a width 1, which can be between 30 mm and 40 mm, or even between 35 mm and 40 mm, being for example 35.5 mm. Width is understood to mean the smallest dimension of the main faces.

[0029] The slice of the pocket-type cells may have a small thickness, for example a thickness of between 5 and 20 mm, or even between 7 mm and 18 mm, better still between 10 mm and 17 mm, for example 16.11 mm.

[0030] Pocket-type cells can thus be flattened. The flattening plane of a pocket-type cell can be defined. The flattening plane is parallel to the main faces of said cell and intersects the edge of the cell so as to possibly form a plane of symmetry for the cell.

[0031] The slice of the pocket-type cells has two large opposite faces and two small opposite faces.

[0032] By "electrical connection tab" is meant a tab protruding through a slot in the pocket formed by the pocket-type cell and acting as a terminal of the cell.

[0033] The electrical connection tabs may be of a substantially rectangular shape before folding. Alternatively, they may have another shape.

[0034] The two electrical connection tabs may be of different thickness, width and length. Alternatively, they have the same dimensions.

[0035] The cathode electrical connection lugs may have a length Lpc of between 20 mm and 40 mm, better between 30 mm and 40 mm, for example 35 mm.

[0036] The cathode electrical connection tabs may have a width lpc of between 20 mm and 30 mm, for example 26 mm.

[0037] The cathode electrical connection tabs may have a very low thickness epc, for example between 0.2 mm and 0.5 mm, for example 0.3 mm.

[0038] The anode electrical connection lugs may have a length Lpa of between 30 mm and 50 mm, or even between 40 mm and 50 mm, for example 45 mm.

[0039] The anode electrical connection tabs may have a width lpa of between 20 mm and 30 mm, for example 26 mm.

[0040] The anode electrical connection tabs may have a very low thickness epa, for example between 0.2 mm and 0.5 mm, for example 0.4 mm.

[0041] The very low thickness of the electrical connection tabs makes it easier to bend them onto the parallel connectors.

[0042] The cathode electrical connection tabs may be made of an electrically conductive material, in particular metal, for example copper. The cathode electrical connection tabs may be coated with nickel.

[0043] The cathode electrical connection legs of the various pocket-type cells of the assembly according to the invention may be made of the same material. Alternatively, they may be made of different materials.

[0044] The anode electrical connection tabs may be made of an electrically conductive material, in particular metal, for example aluminum.

[0045] The anode electrical connection tabs of the different pocket-type cells of the assembly according to the invention may be made of the same material. Alternatively, they may be made of different materials.

[0046] The anode and cathode electrical connection tabs of the same pocket-type cell may be made of different materials.

[0047] The electrical connection tabs of a pouch cell may be located at two opposite ends of the pouch cell.

[0048] The electrical connection tabs of a pocket-type cell may extend before folding in the flattening plane of said cell or parallel to it.

[0049] Preferably, the electrical connection tabs are located on the edge of the cells, in particular on the two smaller opposite faces of the edge.

[0050] The anode electrical connection legs can be coupled to the anode by a side of width lpa.

[0051] The cathode electrical connection legs can be coupled to the cathode by a side of width lpc.

[0052] This coupling of the connection tabs on the anode and the cathode by a side of width 1 pa or lp results in the folding of the electrical connection tabs on the paralleling connectors being done in the direction of the length of the tabs.

[0053] By "parallel connector" is meant an element making it possible to electrically connect together in parallel the pocket-type cells of an assembly according to the invention.

[0054] The paralleling connectors may be made of an electrically conductive material, in particular metal, for example aluminum or copper.

[0055] The two paralleling connectors are preferably of identical shape. Alternatively, they may have different shapes. The paralleling connectors may have a substantially rectangular shape. Alternatively, they may have another shape, for example curved.

[0056] Each paralleling connector may comprise a base portion of substantially rectangular shape in top view and one or more branches, in particular two branches, connecting, in particular perpendicularly, to said base portion.

[0057] The branch(es) may have a substantially rectangular shape when viewed from above.

[0058] The branch(es) may all have the same shape and dimensions. alternatively, they can have different shapes or dimensions.

[0059] The base portion and / or the branch(es) may be flattened and arranged so that the paralleling connector is flat.

[0060] Each paralleling connector may have a comb shape, the branches of the connector connecting to the base portion on the same side thereof.

[0061] Each paralleling connector may comprise two branches, the branches forming substantially a U shape with the base portion. A U shape of the paralleling connectors makes it possible to provide a large connection surface while maintaining a simple shape.

[0062] Each electrical connection tab of a pocket-type cell can be folded onto one face of a branch of a paralleling connector.

[0063] The pocket-type cells of the set can be arranged in pairs of consecutive cells.

[0064] The anode electrical connection tabs of a pair of consecutive cells can be folded onto the same face of the same branch of the anode connector for paralleling the assembly.

[0065] The cathode electrical connection legs of a pair of consecutive cells can be folded onto the same face of the same branch of the cathode connector for paralleling the assembly.

[0066] The consecutive cells forming a pair can be arranged on either side of a branch on which their anode or cathode electrical connection tabs are folded. Alternatively, they can be arranged on the same side of said branch.

[0067] Each branch may carry two electrical connection tabs of two consecutive cells forming a pair of cells, the cells of the pair being in particular arranged on either side of the branch so that their electrical connection tabs folded on said branch come into contact. The ends of the electrical connection tabs may join together. Alternatively, the electrical connection tabs may overlap at least in part.

[0068] The two consecutive cells forming a pair can be arranged symmetrically along a plane parallel to the flattening planes of each of the cells.

[0069] The arrangement of the cells of a pair on either side of a branch allows the assembly to gain in compactness.

[0070] The assembly may comprise one or more spacers.

[0071] The interlayer(s) may have a substantially rectangular parallelepiped shape. The interlayer(s) may be flattened. The interlayer(s) may have two main faces connected by an edge. The dimensions of the main faces of the interlayer(s) may be substantially the same as the di dimensions of the main faces of the pocket-type cells of the assembly.

[0072] The spacers may be made of an electrically insulating material, in particular foam.

[0073] An interlayer, in particular electrically insulating, in particular made of foam, can be arranged between two consecutive cells.

[0074] A spacer may be disposed between consecutive cells of a pair of cells. In one embodiment, a spacer is disposed between consecutive cells of each pair of cells. A spacer may be disposed between two pairs of cells. In one embodiment, a spacer is disposed between each pair of cells.

[0075] The electrical connection tabs can be welded after their bending, in particular by laser, on the paralleling connectors.

[0076] The electrical connection tabs of two consecutive cells forming a cell pair may overlap on the paralleling connector. The electrical connection tabs may be soldered to each other. A pattern may be defined on an overlapping space of the electrical connection tabs and the laser source may pass through said pattern to solder the connection tabs together on the paralleling connector. Passing the laser source over the pattern causes the components to melt and thus solder the elements together.

[0077] The invention also relates, independently or in combination with the above, to a stack of electric accumulator cells, comprising several electrical energy storage assemblies as defined above and two end cheeks between which the electrical energy storage assemblies are arranged.

[0078] The stack may comprise between 5 and 20 electrical energy storage units, or even between 7 and 18, better still between 10 and 15, for example 13 electrical energy storage units.

[0079] The assemblies may be arranged in at least one row, in particular in a single row arranged between the two end cheeks.

[0080] A spacer may be disposed between an end cheek and a cell adjacent to the end cheek.

[0081] In one embodiment, a spacer may be disposed between each end cheek and a cell adjacent to the end cheek.

[0082] The end cheeks may be held clamped by at least one clamping element, each end cheek having in particular at least one notch for receiving the clamping element. The end cheeks may be as described below.

[0083] The clamping element may be as described below. Stacking of electric accumulator cells

[0084] The invention also relates, independently or in combination with the above, to a stack of electric accumulator cells comprising: - two end cheeks, - a plurality of pocket-type electric accumulator cells arranged in at least one row of cells, between the two end cheeks, in particular in a single row of cells, - a plurality of spacers, in particular made of foam, arranged between consecutive cells and / or between an end cheek and a cell adjacent to the end cheek, - optionally a strain gauge, the end cheeks being held tight by one or more clamping elements so as to comply with a clamping force instruction, the strain gauge allowing in particular to monitor the clamping force F of the clamping elements.

[0085] By applying a determined clamping force setpoint in the stack according to the invention, it is possible to control the compression of the cells while leaving the final length of the stack free. In the stack according to the invention, there is thus no fixed length of the stack.

[0086] By “stack length” is meant the length separating two end cheeks, measured along the row of cells along a longitudinal axis X of the row.

[0087] Controlling the compression of the cells is particularly interesting because a cell compressed to the right pressure has a prolonged lifespan. Controlling the compression within the stack according to the invention is made possible by the presence of interlayers, in particular foam, which are flexible elements with a spring force.

[0088] The stack may include a strain gauge, which may enable monitoring of the clamping force F, also called the final clamping force, of the clamping elements. The presence of the strain gauge makes it possible to verify proper control of the compression within the stack.

[0089] The strain gauge may be arranged on one of the clamping elements.

[0090] The strain gauge can be used to measure the elongation of the element(s) tightening in a given direction. Thus, the strain gauge, being calibrated at the time of manufacturing the stack, can make it possible to estimate the force applied.

[0091] The clamping force setpoint can be 0.1 * SN where S is the surface area in mm2 of a main face of a cell. The clamping force setpoint to be applied can be 1.5 to 2 times greater than the value of the final clamping force sought due to taking into account the phenomenon of relaxation.

[0092] The final clamping force F to be obtained may be between 2000 and 6000 N, or even between 3000 and 5000 N, being for example approximately 4000 N. To obtain a final clamping force F of this order, it is necessary to comply with a clamping force setpoint of between 1000 and 10000 N, or even between 2000 and 9000 N, being for example between 6000 and 8000 N.

[0093] The stack of electric accumulator cells may comprise between 2 and 100 pocket-type cells, better between 40 and 80, for example 52 pocket-type cells.

[0094] The end cheeks have a generally parallelepiped shape, in particular a rectangular parallelepiped. The end cheeks may have two main faces connected by an edge. The edge of an end cheek may have two smaller sides and two longer sides. The end cheeks may be made of metal, in particular aluminum.

[0095] The tightening elements may be straps or strapping tapes. The tightening elements are preferably made of metal, for example steel, in particular stainless steel.

[0096] A stack of cells may have between one and six clamping elements, for example four clamping elements.

[0097] Each cheek may have at least one notch for receiving a clamping element. The term "receiving notch" refers to a cutout for receiving at least one clamping element. The notch allows the clamping element to be wedged, and thus prevents it from slipping or moving. Thus, the presence of the receiving notch(s) ensures that the clamping element maintains a minimum length once clamped. The receiving notch(s) may be provided on an edge of an end cheek, in particular on one of the longest sides of the edge.

[0098] In one embodiment, an end cheek has at least one pair of notches, arranged symmetrically on two longer opposite sides of the edge of the end cheek.

[0099] Alternatively or additionally, the receiving notch(s) may extend across the entire width of an end cheek, in particular parallel to an edge of the end cheek. The receiving notch(s) may take the form of a groove.

[0100] The two end cheeks may have as many receiving notches as each other, in particular arranged substantially similarly.

[0101] In one embodiment, each cheek has as many receiving notches, in particular in the form of a groove, as there are clamping elements.

[0102] An interlayer, in particular made of foam, can be placed between all the cells. consecutive. A spacer, in particular made of foam, may be arranged between an end cheek and a cell adjacent to the end cheek. In one embodiment, a spacer may be arranged between each end cheek and a cell adjacent to the end cheek.

[0103] The plurality of cells may comprise several electrical energy storage assemblies. Each electrical energy storage assembly may comprise a plurality of pouch-type electrical accumulator cells as described above. In particular, each pouch-type cell may comprise: - a cathode and an anode enclosed in a pocket, - an electrical connection cathode lug electrically coupled to the cathode, and - an anode electrical connection tab electrically coupled to the anode, the anode and cathode electrical connection tabs protruding from the pocket.

[0104] The plurality of cells arranged in the stack may comprise between 5 and 20 electrical energy storage assemblies, or even between 7 and 18, better still between 10 and 15, for example 13 electrical energy storage assemblies.

[0105] Furthermore, each electrical energy storage assembly may comprise a cathode connector and an anode connector for paralleling the cells of the plurality of cells of the assembly, as described above. The cathode and anode connectors may each have at least one flattened portion, the cathode legs each being folded onto the cathode connector and the anode legs each being folded onto the anode connector, so as to electrically connect together the cathodes of the pouch-type cells on the one hand and the anodes of the pouch-type cells on the other hand.

[0106] Each paralleling connector may comprise a base portion of substantially rectangular shape in top view and one or more branches, in particular two branches, connecting, in particular perpendicularly, to said base portion, each paralleling connector having in particular a comb shape, the branches of the connector connecting to the base portion on the same side thereof.

[0107] Each paralleling connector may comprise two branches, the branches forming substantially a U with the base portion.

[0108] Each electrical connection tab of a pocket-type cell can be folded onto one face of a branch of a paralleling connector.

[0109] Each branch may carry two electrical connection tabs of two consecutive cells forming a pair of cells, the cells of the pair being in particular arranged on either side of the branch so that their electrical connection tabs folded on said branch come into contact.

[0110] An interlayer, in particular made of foam, may be arranged between the cells of each electrical energy storage assembly. An interlayer, in particular made of foam, may be arranged between each electrical energy storage assembly.

[0111] Each electrical energy storage assembly included in the stack may have, as a variant or additionally, any of the characteristics as previously defined above.

[0112] The invention also relates, independently or in combination with the above, to an electric accumulator module comprising: - two stacks of pocket-type electric accumulator cells as defined above, arranged so that the longitudinal axes of the rows of each stack are parallel to each other, - a heat exchanger plate arranged between the two stacks and in thermal contact with them, the heat exchanger plate being oriented substantially parallel to the longitudinal axes of the rows of each stack.

[0113] The cells may extend parallel to a general flattening plane of the cells, the heat exchanger plate being oriented substantially perpendicular to the general flattening plane of the cells.

[0114] The two stacks may comprise the same number of pocket-type cells. The two stacks may comprise the same number of interlayers, in particular foam. The alternation between interlayers and pocket-type cells may be identical in the two stacks.

[0115] The term “front of the module” refers to a side of the module where two end cheeks, one from each stack, are aligned.

[0116] The term “rear of the module” refers to the side opposite the front of the module.

[0117] A front end cheek and a rear end cheek are distinguished for each stack. The front end cheeks of the two stacks may be identical in shape and dimensions. The rear end cheeks of the two stacks may be identical in shape and dimensions.

[0118] The two stacks may comprise the same number of clamping elements.

[0119] The two stacks of a module may have different lengths. Indeed, given that there is a single clamping force setpoint, depending on the crushing of the interlayers and cells, which may depend on the age or nature of the foam for example, or on the respective age of the cells, two stacks having the same number of cells and interlayers may have different or identical lengths. The stacks may alternatively have the same length.

[0120] Whether or not the stacks are of the same length results from crushing during tightening and does not correspond to two different embodiments.

[0121] The rear end cheeks of the module may be offset from each other. the other. They are generally not aligned. This non-alignment comes from the fact that the length of the two stacks of the module can be different. Alternatively, the rear end cheeks are aligned.

[0122] The presence of a heat exchanger plate and its arrangement within the module make it possible to obtain efficient cooling, particularly at the heart of the module, while having a compact and easy-to-assemble module.

[0123] The heat exchanger plate may have internal channels through which a cooling liquid, in particular glycolated water, flows.

[0124] The heat exchanger plate may have four sub-parts formed by extrusion. The heat exchanger plate may be made of plastic.

[0125] The heat exchanger plate may be welded to at least one cheek of each stack. In one embodiment, the heat exchanger plate is welded to both end cheeks located at the front of the module.

[0126] A thermal paste may be placed between the heat exchanger plate and the cell stacks. The thermal paste may be deposited on the entire side of the cell edge adjacent to the heat exchanger plate, except for the areas where the clamping elements pass. The thermal paste improves the thermal conductivity between the heat exchanger plate and the cells. It therefore improves the cooling of the module. Electrical connection bus bar

[0127] The invention also relates, independently or in combination with the above, to a bus bar for electrically connecting several sets of electric accumulator cells, comprising:

[0128] - a plurality of rigid elements, each comprising at least one plate of electrical connection,

[0129] - one or more flexible elements connecting the rigid elements together, the flexible element(s) being able to bend so that the bus bar adapts to a variable spacing between the sets of electric storage cells to be connected.

[0130] The bus bar can also be called “bare omnibus” in French.

[0131] By "bendable" is meant that the flexible elements can, when the spacing between two sets of electric accumulator cells to be connected requires it, bend flexibly and take substantially the shape of a U to allow good arrangement of the rigid elements on the groups of cells. Conversely, when the situation requires it, the flexible elements can extend over their entire length and allow greater spacing of the sets of cells to be connected.

[0132] The bus bar according to the invention can, by its adaptability, be suitable for different em stacking of sets of electric accumulator cells. It also allows for taking into account the aging of the cells, which tends to manifest itself by their swelling, thereby modifying the spacing between the sets of cells to be connected.

[0133] The bus bar may be configured to electrically connect the sets of electric storage cells in series.

[0134] The rigid elements of the bus bar may be flat. They may all be in the same plane. They may be aligned along a longitudinal axis. This is the longitudinal axis of the bus bar.

[0135] The bus bar may have a substantially rectilinear profile in longitudinal section.

[0136] The bus bar may comprise an even or odd number of rigid elements. In embodiments, the bus bar may comprise three, five or seven rigid elements.

[0137] One or more rigid elements may be intended to be arranged each at least in part on two consecutive sets of electric accumulator cells.

[0138] One or more rigid elements may be intended to be arranged each on a single set of cells.

[0139] A set of electric accumulator cells may only be in contact with a single rigid element.

[0140] The connection plate of the rigid elements can be brought into contact, in particular welded, at least in part to a connector connecting together the cells forming a set of electric accumulator cells.

[0141] In one embodiment, the bus bar according to the invention makes it possible to connect in series several electrical energy storage assemblies as previously defined and the connection plate of the rigid elements is brought into contact, in particular welded, at least in part to a paralleling connector, in particular to the base portion of the paralleling connector.

[0142] Each set of electric accumulator cells connected to the bus bar may be an electrical energy storage set as previously defined, and may have, as a variant or additionally, any of the characteristics as previously defined above.

[0143] The rigid elements may have a substantially rectangular shape in top view.

[0144] The rigid elements may take the form of a frame. The frame may contain an electrical connection plate. The electrical connection plate may be arranged along one side of the frame, in particular parallel to the longitudinal axis of the bus bar. The electrical connection plate may have the same length as the frame. The electrical connection plate may have a width less than the width of the frame, in particular less than half the width of the frame.

[0145] The electrical connection plate may be made of an electrically conductive material, in particular metal, for example aluminum.

[0146] The frame may be partly hollow.

[0147] The frame may be made of a conductive material, in particular metal, for example aluminum or copper.

[0148] The bus bar may include a plurality of non-terminal rigid members that are identical in shape and dimensions, as well as a terminal rigid member located at one end of the bus bar.

[0149] The non-terminal rigid elements can each be arranged in part on two sets of consecutive electric accumulator cells to be connected.

[0150] The terminal element may be of smaller dimensions than the non-terminal elements. In one embodiment, the terminal element is shorter than the non-terminal elements, the length of a rigid element being measured along the longitudinal axis of the bus bar.

[0151] The terminal element may be arranged on a single set of electric accumulator cells.

[0152] The flexible element(s) may be made of a polymer material, for example a polyethylene film or epoxy.

[0153] One or two flexible elements can be inserted into one side of the frame formed by each rigid element.

[0154] In one embodiment, the flexible element(s) insert into the side opposite to the side along which the electrical connection plate is arranged.

[0155] In one embodiment, the bus bar comprises a single flexible element, passing through one side of each rigid element and connecting the rigid elements together in succession.

[0156] The flexible element can be welded to each rigid element.

[0157] The flexible element may be arranged so that a length Ls of flexible element, for example between 20 mm and 50 mm, separates two consecutive non-terminal rigid elements. The flexible element can be arranged so that the length of flexible element separating a terminal rigid element from another rigid element is different from Ls, in particular less than Ls

[0158] In another embodiment, the bus bar comprises several flexible elements, each flexible element connecting two consecutive rigid elements. The flexible elements may all have the same length. Alternatively, the flexible elements may have different lengths. The flexible element connecting a terminal rigid element to another rigid element may be of a different length, in particular shorter, than the flexible elements separating two non-terminal rigid elements.

[0159] Each rigid element may include one or more sensors making it possible to monitor cell temperature and / or voltage.

[0160] The rigid elements may have different numbers and / or types of sensors.

[0161] In one embodiment, each rigid element comprises a first sensor for monitoring the temperature and a second sensor for monitoring the voltage of the set(s) of electric accumulator cells.

[0162] In another embodiment, each rigid element comprises a sensor for monitoring the voltage of the set or sets of electric accumulator cells and one of the two or both terminal rigid elements also comprises a sensor for monitoring the temperature.

[0163] The presence of a sensor measuring the temperature makes it possible to detect any thermal runaway of a cell. Under certain conditions, the presence of a sensor at each end of the bus bar in a rigid terminal element can make it possible to highlight the evolution of the temperature within the row of sets of cells to be connected.

[0164] The sensor(s) may comprise one or more flexible printed circuits provided with tracks, in particular made of copper, brought into contact with the cells.

[0165] A flexible printed circuit may have a first portion inserted into one side of the frame formed by the rigid element, and one or more complementary portions extending into the frame and attached perpendicularly to the first portion.

[0166] The temperature sensor(s) may be arranged in the middle of one of the sets of cells to be connected.

[0167] The voltage sensor(s) can be arranged more freely within the rigid element where the same potential applies.

[0168] In an embodiment where there is a single flexible element, the flexible element can carry one or more conductive tracks, so as to transmit at least one piece of information measured by the sensor(s).

[0169] The flexible element may contain as many conductive tracks as there are sensors in the bus bar. A conductive track may extend from each rigid element from which it sends back at least one piece of information measured by a sensor, to a final end of the bus bar.

[0170] The conductive tracks carried by the flexible element may thus not have the same length.

[0171] The conductive tracks may be analog signal tracks.

[0172] The invention also relates, independently or in combination with the above, to a stack of electric accumulator cells comprising: - two end cheeks, - a plurality of electric accumulator cells arranged in at least one row between the two end cheeks, the cells being distributed in several sets of cells to be connected in series, in particular in a single row, - a first bus bar as previously defined, arranged on the top of the stack, and a second bus bar as previously defined, arranged on the bottom of the stack, the bus bars connecting the sets of cells in series.

[0173] The "top" of the stack refers to a side of the stack extending perpendicular to the end cheeks. The "bottom" of the stack is the side opposite the "top".

[0174] The term "front" of the stack refers to one of the sides carrying an end cheek.

[0175] The bus bars may include a connection bar.

[0176] By “connection bar” is meant a part located at one end of the bus bar allowing the transmission of power and / or signals, for example voltage or temperature, to a terminal box.

[0177] The connecting bar may have a main portion in the form of a straight bar and terminate in a bent end on one side and a flat end on the other. The bent end may be attached to a rigid member of the bus bar. The main portion of the connecting bar may extend along a portion of the end flange located at the front of the stack.

[0178] The connecting bar can be fixed, in particular welded, to the end cheek at its flat end.

[0179] The end cheek located at the front of the stack may have on its edge, in particular on the two smaller sides of the edge, a notch each allowing the passage of a connection element.

[0180] A flexible printed circuit may extend from the rigid member attached to the bent end of the connecting bar, to the flat end of the connecting bar.

[0181] The flexible printed circuit may be arranged so that a length lc of flexible printed circuit, for example between 5 and 15 cm, protrudes from the flat end of the connection bar so as to connect to a terminal box.

[0182] The flexible printed circuit present in the connection bar makes it possible to transmit signals, such as voltage and temperature, fed back by the conductive track(s) of the flexible element, and / or power to a terminal box. The connection bar of the first bus bar can transmit signals and power to a terminal box. The connection bar of the second bus bar can only transmit signals to the terminal box and not power.

[0183] In one embodiment, the terminal element of each bus bar is contiguous with an end flange.

[0184] The rigid elements of the first bus bar may be offset by a set of cells relative to the rigid elements of the second bus bar so that the current flows successively from top to bottom and from bottom to top in the cells of the stack.

[0185] Each set of electric accumulator cells may be an electrical energy storage assembly as defined above. Each electrical energy storage assembly may comprise a group of pouch-type electric accumulator cells. Each pouch-type cell may comprise: - a cathode and an anode enclosed in a pocket, - an electrical connection cathode lug electrically coupled to the cathode, and - an anode electrical connection tab electrically coupled to the anode, the anode and cathode electrical connection tabs protruding from the pocket.

[0186] Each electrical energy storage assembly may comprise a cathode connector and an anode connector for paralleling the cells, the cathode and anode connectors each having at least one flattened portion, the cathode tabs each being folded onto the cathode connector and the anode tabs each being folded onto the anode connector, so as to electrically connect together the cathodes of the different pocket-type cells on the one hand and the anodes of the different pocket-type cells on the other hand.

[0187] The connection plate of each rigid element can be brought into contact, in particular welded, at least in part to a paralleling connector.

[0188] The electric accumulator cells may be pocket-type cells and the stack may comprise: - two end cheeks, - a plurality of foam inserts, arranged between consecutive cells and / or between a cell and an end cheek contiguous to the cell, - optionally a strain gauge, the end cheeks being held tight by one or more clamping elements so as to comply with a clamping force setpoint F, the strain gauge allowing in particular to monitor the clamping force F of the clamping elements.

[0189] Each stack may be a stack of electric accumulator cells as described above and may have, alternatively or additionally, any of the characteristics as previously defined above.

[0190] The invention also relates, independently or in combination with the above, to an electric accumulator module comprising: - two stacks of electric accumulator cells as previously defined, arranged so that the longitudinal axes of the rows of each em- stacking are parallel to each other, - a heat exchanger plate arranged between the two stacks and in thermal contact with them, the heat exchanger plate being oriented substantially parallel to the longitudinal axes of the rows of each stack.

[0191] The cells may extend parallel to a general flattening plane of the cells, the heat exchanger plate being oriented substantially perpendicular to the general flattening plane of the cells. Two bus bar interconnection set

[0192] The invention also relates, independently or in combination with the above, to an assembly for interconnecting two bus bars comprising:

[0193] - a first flat interconnection part comprising:

[0194] - a base, substantially rectangular in top view, - a connecting part, substantially rectangular in top view, - a central part, substantially rectangular in top view, having a first end connected perpendicularly to the base and a second end connected perpendicularly to the connecting part,

[0195] - a second curved interconnecting part comprising:

[0196] - a base, substantially rectangular in top view, - a connecting part, substantially rectangular in top view, - a central part, at least in part substantially rectangular in top view, having a first flat end connected perpendicularly to the base and a second bent end connected perpendicularly to the connection part,

[0197] each base of the two interconnection parts being intended to be connected to one of the bus bars and the connection parts of the two interconnection parts being in particular intended to be brought into contact with each other, being in particular in contact with each other, in particular when using the interconnection assembly to interconnect two bus bars.

[0198] The bent end of the second interconnection piece can be arranged so that the connection part of the first interconnection piece can overlap at least in part on the connection part of the second interconnection piece, when the bases of the two interconnection pieces are aligned horizontally, in particular when the bases of the two interconnection pieces are connected to two bus bars arranged at the same height.

[0199] The interconnection parts may be made of an electrically conductive material, in particular metal, for example aluminum or copper.

[0200] The base of the interconnection parts may have a shoulder. This shoulder makes it easier to integrate it into the bus bar.

[0201] The invention also relates, independently or in combination with what above, an electric accumulator module comprising:

[0202] - two stacks of electric accumulator cells each comprising: - two end cheeks, - a plurality of electric accumulator cells arranged in at least one row between the two end cheeks, in particular in a single row, the cells being distributed into several sets of cells to be connected in series,

[0203] the two stacks being arranged side by side in parallel so that two end cheeks, one of each stack, are aligned at the front of the module,

[0204] - two bus bars, each arranged on the bottom of a stack so that the two bus bars are side by side and parallel to each other, each bus bar connecting in series the sets of cells in a stack,

[0205] - an interconnection assembly as defined previously connecting the two buses bar between them.

[0206] The term “front of the module” refers to a side of the module where two end cheeks, one from each stack, are aligned.

[0207] The term “rear of the module” refers to the side opposite the front of the module.

[0208] The interconnection assembly according to the invention can allow series connection the two stacks of electric accumulator cells in the module.

[0209] Each bus bar of the module can include: - a plurality of rigid elements, each comprising at least one electrical connection plate, - one or more flexible elements connecting the rigid elements together,

[0210] the flexible element(s) being able to bend so that the bus bar adapts to a variable spacing of the sets of electric accumulator cells to be connected.

[0211] The module may comprise a plurality of non-terminal rigid elements which are identical in shape and dimensions, as well as a terminal rigid element located at one end of the bus bar and contiguous to an end cheek located at the rear of the module.

[0212] An interconnection piece may be inserted into a terminal element of a bus bar of each stack so that the connection portion of the interconnection piece is arranged between the two stacks.

[0213] The first flat interconnection piece may be disposed at least partially above the second curved interconnection piece such that the interconnection portions of the two interconnection pieces overlap.

[0214] This configuration can occur when the stacks have the same length, or different lengths.

[0215] The stacks may have different lengths, and the end cheeks and terminal elements of the two bus bars may be offset at the rear of the module, the connection parts of the interconnecting pieces may be aligned between the two stacks, the connecting parts can be long enough to touch each other at one end.

[0216] The first flat interconnection piece can slide relative to the second curved interconnection piece, thereby allowing the two connecting portions of the interconnection pieces to be offset relative to each other, while maintaining their contact over at least a portion of their length. The electrical connection can take place, despite the offset between the stacks of different lengths.

[0217] Each bus bar may be a bus bar within the meaning of the invention and may have, as a variant or additionally, any of the characteristics as previously defined above.

[0218] Each stack may be a stack of electric accumulator cells within the meaning of the invention and may have, as a variant or additionally, any of the characteristics as previously defined above.

[0219] Each set of electric accumulator cells connected to the bus bar may be an electrical energy storage set as previously defined, and may have, alternatively or additionally, any of the characteristics as previously defined above. Electric accumulator module pack

[0220] The invention also relates, independently or in combination with the above, to a pack of electric accumulator modules comprising:

[0221] - several electric accumulator modules each comprising: • two stacks of electric accumulator cells each comprising: • two end cheeks, • a plurality of electric accumulator cells arranged in at least one row between the two end cheeks, in particular in a single row,

[0222] the two stacks being arranged side by side in parallel so that two end cheeks, one of each stack, are aligned at the front of the module, • a heat exchanger plate arranged between the two stacks and in thermal contact with them, the plate protruding from the two stacks by a final end at the rear of the module,

[0223] the modules being aligned laterally, the contiguous cheeks of two consecutive modules being fixed, in particular welded, between them,

[0224] - a terminal box, arranged on the end cheeks located at the front of the modules,

[0225] - one or more fixing bars, connecting the modules together, the bar(s) of fixing being fixed to the heat exchanger plate of each module at the final end of the heat exchanger plate.

[0226] The presence of fixing bars and their arrangement according to the invention makes it possible to ensure good rigidity of the module in cases where the stacks of the different modules do not have the same length, thereby introducing an offset between the end cheeks at the rear of the modules and preventing the end cheeks from being welded together.

[0227] In one embodiment, the pack comprises two fixing bars.

[0228] By "laterally" we mean a direction perpendicular to the rows of em piles.

[0229] The end cheeks at the rear of the module may be set back from the fixing bar.

[0230] In one embodiment the pack may contain four modules.

[0231] The fixing bar(s) may be welded to the heat exchanger plate. The fixing bar(s) may be attached to an edge parallel to the end flanges of the heat exchanger plate.

[0232] Each stack may be a stack of electric accumulator cells as defined above and may have, alternatively or additionally, any of the characteristics as previously defined above.

[0233] The terminal box may be located on the main faces of the end cheeks. The terminal box may contain the electronics enabling the measurement of the voltage and / or the temperature and the balancing of the cells with each other. The terminal box may connect the modules in series.

[0234] In an embodiment where the stack is a stack of electric accumulator cells as defined above, the terminal box connects the modules in series by connecting, by connectors, the flexible printed circuits protruding from the flat end of the connection bar of the stacks of modules to be connected.

[0235] The invention also relates, independently or in combination with the above, to a column of packs of electric accumulator modules comprising several packs of electric accumulator modules as defined previously stacked on top of each other, the terminal boxes of each pack being connected to each other.

[0236] In one embodiment, the column comprises four packs of electric accumulator modules.

[0237] The end cheeks located at the front of two packs stacked on top of each other may be in contact. They may be fixed together.

[0238] The end cheeks located at the front of the packs can mechanically support the stacking of the packs.

[0239] The invention also relates, independently or in combination with the above, to an electrical energy storage device comprising an enclosure, and, inside the enclosure: - two rows of columns of electric accumulator module packs as defined previously, the columns of each row being arranged side by side, - a control room, located in particular as an extension of the two rows.

[0240] The control room may comprise at least one element from among: a cold production system, a power conversion system, a water cooling system, in particular coupled to the cold production system, and an electronic control unit.

[0241] The power conversion system may be accessible from one end of the enclosure. The cold production system may be accessible from an end opposite thereto.

[0242] A row of columns may comprise between 2 and 10 columns of electric accumulator module packs, better between 4 and 8, for example 5 columns.

[0243] The two rows of columns can be arranged without a traffic corridor between them.

[0244] Such a device has the advantage of allowing a large number of accumulator modules to be placed inside the enclosure, and thus increasing the storage capacity.

[0245] This configuration also lends itself well to cooling by circulation of liquid, in particular water, of the modules, which makes it possible to gain in compactness and efficiency.

[0246] Furthermore, in the absence of a central circulation corridor, the risk of having a person present in the enclosure in the event of an incident is eliminated.

[0247] The enclosure can be defined by a maritime standard container, in particular the 20-foot standard. Brief description of the drawings

[0248] The invention may be better understood by reading the detailed description which follows, a non-limiting example of implementation of the invention, and by examining the attached drawing, in which:

[0249] [Fig-1] [Fig.l] is a perspective, schematic and partial view of a device electrical energy storage according to the invention.

[0250] [Fig.2] [Fig.2] shows in perspective a column of electric accumulator module packs.

[0251] [Fig.3] [Fig.3] illustrates an isolated pack of electric accumulator modules, in perspective.

[0252] [Fig.4] [Fig.4] is a front view of the electric battery module pack of [Fig.3], with the terminal box cover removed.

[0253] [Fig.5] [Fig.5] is a rear perspective view of a pack of electric accumulator modules in which the stacks of modules are not the same length.

[0254] [Fig.6] [Fig.6] is a rear perspective view of the electric battery module pack of [Fig.3] in which the stacks of modules have the same length.

[0255] [Fig.7] [Fig.7] represents in perspective an electric accumulator module whose two stacks have the same length.

[0256] [Fig.8] [Fig.8] represents in perspective an electric accumulator module whose two stacks do not have the same length.

[0257] [Fig.9] [Fig.9] is a top view of the module of [Fig.7].

[0258] [Fig. 10] [Fig. 10] is a bottom view of the module of [Fig.7].

[0259] [Fig. 11] [Fig. 11] is a top view of the module of [Fig.8].

[0260] [Fig. 12] [Fig. 12] is a bottom view of the module of [Fig.8].

[0261] [Fig. 13] [Fig. 13] represents an interconnection assembly

[0262] [Fig. 14] [Fig. 14] illustrates the first interconnecting piece of the assembly of [Fig.13],

[0263] [Fig. 15] [Fig. 15] illustrates the second interconnecting part of the assembly of [Fig.13],

[0264] [Fig. 16] [Fig. 16] shows an isolated bus bar connected to the interconnecting piece beyond [Fig. 14],

[0265] [Fig. 17] [Fig. 17] shows an isolated bus bar connected to the interconnecting piece beyond [Fig. 15].

[0266] [Fig. 18] [Fig. 18] shows an isolated bus bar intended to come on top of a stack of an electric accumulator module.

[0267] [Fig. 19] [Fig. 19] represents an isolated stack of electric accumulator cells.

[0268] [Fig.20] [Fig.20] is a perspective view of an end cheek positioned at the front of the stack of [Fig. 19].

[0269] [Fig.21] [Fig.21] is a perspective view of an end cheek positioned at the rear of the stack of [Fig. 19].

[0270] [Fig.22] [Fig.22] is a perspective view of the heat exchanger plate.

[0271] [Fig.23] [Fig.23] is a perspective view of a foam interlayer.

[0272] [Fig.24] [Fig.24] represents an electrical energy storage assembly according to the invention.

[0273] [Fig.25] [Fig.25] is a view of a detail of [Fig.24] before folding the electrical connection tabs of the pocket-type electric accumulator cells.

[0274] [Fig.26] [Fig.26] is a perspective view of a paralleling connector.

[0275] [Fig.27] [Fig.27] represents a pocket-type electric accumulator cell, perspective view. Detailed description

[0276] [Fig.l] illustrates an electrical energy storage device 1 comprising an enclosure 2. Inside the enclosure 2, there are two rows 3 and 4 of columns 5 of packs 6 of electrical accumulator modules arranged side by side, and a control room 7 located as an extension of the two rows 3 and 4.

[0277] A row of columns 3 or 4 comprises five columns 5 of packs 6 of electric accumulator modules.

[0278] The two rows 3 and 4 are arranged without a traffic lane between them.

[0279] Enclosure 2 is a 20-foot maritime standard container.

[0280] [Fig.2] represents a column 5 of packs 6 of electric accumulator modules. Column 5 comprises four packs 6 of electric accumulator modules.

[0281] Each pack 6, illustrated in isolation in Figures 3 to 6, comprises:

[0282] - four electric accumulator modules 8 each comprising: • two stacks 9 of electric accumulator cells each comprising: • two end cheeks 10 and 11, • a plurality of electric accumulator cells arranged in a single row 12 between the two end cheeks 10 and 11,

[0283] the two stacks 9 are arranged side by side in parallel so that two end cheeks 10 are aligned at the front of the module, • a heat exchanger plate 13 arranged between the two stacks 9 and in thermal contact with them, the plate 13 protrudes from the two stacks 9 by a final end 14 at the rear of the module 8,

[0284] the modules 8 are aligned laterally, the contiguous cheeks 10 of two consecutive modules 8 are welded together,

[0285] - a terminal box 15, arranged on the end cheeks 10 located at the front of the modules 8,

[0286] - two fixing bars 16, connecting the modules 8 together, the fixing bars 8 are fixed to the heat exchanger plate 13 of each module 8 at the final end 14 of the heat exchanger plate 13.

[0287] The two stacks 9 of a module 8 of a pack 6 may be of the same length as illustrated in [Fig.6] or of different length as shown in [Fig.5]. The end cheeks 11 at the rear of the module 8 may be set back from the bars of attachment 16, as shown in Figures 5 and 6.

[0288] The terminal box 15 is located on the main faces 19 of the end cheeks 10.

[0289] The terminal boxes 15 of the packs 6 of the column of packs 5 are connected between them. The end cheeks 10 located at the front of the packs stacked on top of each other are in contact and fixed to each other. These cheeks 10 mechanically support the stacking of the packs 6.

[0290] Figures 7 and 8 show in isolation an electric accumulator module 8 when the two stacks 9 of the module 8 are respectively of the same length or of different lengths. Each stack 9 is in fact subject to a tightening instruction F and not to a stack length instruction. Two stacks 9 having the same number of cells can thus have different or identical lengths.

[0291] Whether or not the stacks are of the same length results from crushing during tightening and does not correspond to two different embodiments.

[0292] Figures 9 and 11 are top views respectively of the modules of Figures 7 and 8. Figures 10 and 12 are bottom views respectively of the modules of Figures 7 and 8.

[0293] The electric accumulator cells arranged in a single row 12 between the end cheeks 10 and 11 of each stack 9 can be divided into several sets 20 of cells to be connected in series. Each stack 9 comprises 13 sets 20 of cells to be connected in series.

[0294] A bus bar 21 is arranged on the top of each stack 9.

[0295] A bus bar 22 is arranged on the bottom of each stack 9.

[0296] The bus bars are arranged so that the two bus bars 21 at the top of the stack 9 on the one hand and the bus bars 22 at the bottom of the stack 9 on the other hand are side by side and parallel to each other, each bus bar connecting in series the sets 20 of cells of a stack 9.

[0297] An interconnection assembly 23, as illustrated in isolation in [Fig.13], connects in series the two bus bars 22 located on the bottom of the module 8. The interconnection assembly 23 comprises:

[0298] - a first flat interconnection part 24, shown alone in [Fig. 14], including:

[0299] - a base 25, substantially rectangular in top view, - a connection part 26, substantially rectangular in top view, - a central part 27, substantially rectangular in top view, having a first end connected perpendicularly to the base 25 and a second end connected perpendicularly to the connection part 26,

[0300] - a second curved interconnection piece 28, shown alone in [Fig.15], including:

[0301] - a base 29, substantially rectangular in top view, - a connection part 30, substantially rectangular in top view, - a central part 31, at least in part substantially rectangular in top view, having a first flat end 32 connected perpendicularly to the base 29 and a second bent end 33 connected perpendicularly to the connection part 30.

[0302] The bent end 33 of the second interconnection piece 28 is arranged so that the connection portion 26 of the first interconnection piece 24 partly overlaps the connection portion 30 of the second interconnection piece 28, the bases 25 and 28 of the two interconnection pieces 24 and 28 being aligned horizontally.

[0303] The interconnecting parts 24 and 28 are made of metal.

[0304] The bases 25 and 29 of the interconnection pieces 24 and 28 have a shoulder 34 which facilitates their integration into the bus bars 22.

[0305] The bus bars 22 of each stack 9 of the module 8 are shown in isolation in Figures 16 and 17 and a bus bar 21 is shown in isolation in [Fig.14],

[0306] Each bus bar 21, 22 comprises:

[0307] - seven rigid elements 35, each comprising at least one connection plate electric 37,

[0308] -a flexible element 36 connecting together the rigid elements 35, the flexible element 36 can bend so that the bus bar 21, 22 adapts to a variable spacing between the sets 20 of electric accumulator cells to be connected in series.

[0309] The rigid elements 35 of the bus bar 21, 22 are flat. They are all in the same plane. They are aligned along a longitudinal axis X. This is the longitudinal axis of the bus bar.

[0310] The bus bar 21, 22 has a substantially rectilinear profile in longitudinal section.

[0311] The rigid elements 35 have a substantially rectangular shape in top view.

[0312] The rigid elements 35 take the form of a frame 38. The electrical connection plate 37 is arranged along one side of the frame 38 parallel to the longitudinal axis X of the bus bar 21, 22. The electrical connection plate 37 has the same length as the frame 38 and a width less than half the width of the frame 38.

[0313] The electrical connection plate 37 is made of aluminum

[0314] The frame 38 is partly hollow.

[0315] The frame 38 is made of a conductive material, for example aluminum.

[0316] The bus bar 21, 22 comprises six non-terminal rigid elements 39 which are identical in shape and dimensions, as well as a terminal rigid element 40 located at a end of bus bar 21, 22.

[0317] The non-terminal rigid elements 39 are each arranged in part on two sets 20 of consecutive electric accumulator cells to be connected, as visible in Figures 7 and 8.

[0318] The terminal element 40 is of smaller dimensions than the non-terminal elements 39. The terminal element 40 is shorter than the non-terminal elements 39, the length of a rigid element 35 being measured along the longitudinal axis X of the bus bar 21, 22.

[0319] The terminal element 40 is arranged on a single set 20 of electric accumulator cells. The terminal element 40 of each bus bar 21, 22 is contiguous to an end cheek 10, 11.

[0320] The first interconnection piece 24 is inserted into the terminal element 40 of the bus bar 22 of [Fig. 16]. The second interconnection piece 28 is inserted into the terminal element 40 of the bus bar 22 of [Fig. 17].

[0321] The bus bars 22 are arranged on the bottom of the stacks 9 so that the connection parts 26, 30 of the interconnection assembly 23 come into contact. When the stacks 9 of the module 8 are of the same length, as in FIGS. 7, 9 and 10, the connection parts 26 and 30 overlap over their entire length thanks to the bent end 33 of the second interconnection part 28.

[0322] When the stacks 9 of the module 8 are of different lengths, as in FIGS. 8, 11 and 12, the first flat interconnection piece 24 can slide relative to the second curved interconnection piece 28, thus allowing the two connection parts 26 and 30 of the interconnection pieces to be offset relative to each other, while maintaining their contact over at least part of their length. The electrical connection can take place, despite the offset between the stacks of different lengths.

[0323] The flexible element 36 is made of a polymer material, for example a polyethylene film or epoxy.

[0324] The flexible element 36 is inserted into the side opposite to the side along which the electrical connection plate 37 is arranged.

[0325] Each rigid element 35 comprises a first sensor 41 for monitoring the temperature and a second sensor 42 for monitoring the voltage of the set(s) 20 of electric accumulator cells.

[0326] The flexible element may comprise as many conductive tracks as there are sensors 41, 42. Each conductive track may extend from a rigid element 35 from which it sends at least one piece of information from a sensor 41 or 42 to one end of the bus bar 21, 22.

[0327] The sensors 41, 42 comprise one or more flexible printed circuits 43 provided of copper tracks, brought into contact with the cells.

[0328] A flexible printed circuit 43 may have a first portion inserted into one side of the frame 38 formed by the rigid element 35, and one or more complementary portions extending into the frame 38 and attached perpendicularly to the first portion.

[0329] Each bus bar 21, 22 has a connection bar 17

[0330] The connection bar 17 is located at one end of the bus bar 21, 22 and makes it possible to transmit the power and / or the signals, for example the voltage or the temperature, to the terminal box 15 of the pack 6 containing the module 8 which carries the bus bar on one of its stacks 9.

[0331] The terminal box 15 connects in series the modules 8 of a pack 6 of electric accumulator modules by means of connectors 18 connecting together the flexible printed circuits 43 protruding from the connection bars 17 of the bus bars 21, 22 arranged on the stacks 9 of the modules 8.

[0332] The connecting bar 17 has a main part 44 in the form of a straight bar and ends with a bent end 45 on one side and a flat end 46 on the other. The bent end 45 is attached to a rigid element 35 of the bus bar 21, 22. The main part 44 of the connecting bar 17 extends along a main face 19 of the end cheek 10 located at the front of the stack 9.

[0333] The connecting bar 17 is welded to the end cheek 10 at its flat end 46.

[0334] The end cheek 10 located at the front of the stack 9, shown in [Fig.20], has two main faces 19 connected by an edge 47. It has on each of the two smaller sides of the edge 47, a notch 48 each allowing the passage of a connection bar 17.

[0335] A flexible printed circuit 43 extends from the rigid element 35 attached to the bent end 45 of the connection bar 17, to the flat end 46 of the connection bar 17. A length lc of flexible printed circuit 43, for example between 5 cm and 15 cm, protrudes from the flat end 46 of the connection bar 17 so as to connect to the terminal box 15.

[0336] Within a stack 9, the rigid elements 35 of the first bus bar 21 arranged on the top of the stack are offset by a set 20 of cells relative to the rigid elements 35 of the second bus bar 22 arranged on the bottom of the stack so that the current flows successively from the top to the bottom and from the bottom to the top in the cells of the stack 9, as illustrated in FIGS. 9 and 10.

[0337] [Fig. 19] represents an isolated stack 9 comprising:

[0338] - two end cheeks 10,11, - a plurality of pocket-type electric accumulator cells 50 arranged in a row 12 of cells between the two end cheeks 10 and 11 and distributed in 20 electrical energy storage units,

[0339] - a plurality of foam spacers 51, shown isolated in [Fig.23], arranged between consecutive cells and between an end cheek and a cell adjacent to the end cheek, the end cheeks 10, 11 being held clamped by four clamping elements 49 so as to comply with a clamping force setting F.

[0340] The clamping elements 49 are steel strapping bands.

[0341] The end cheek 10 located at the front of the stack, shown in [Fig.20], and the end cheek 11 located at the rear of the stack, illustrated in [Fig.21], have a flattened rectangular parallelepiped shape. The end cheeks 10 and 11 are made of metal.

[0342] They each have four pairs of notches 52. The notches 52 of a pair are arranged symmetrically on the two longest sides of the edge 47 of the end cheeks.

[0343] The plurality of cells of the stack 9 comprises 13 electrical energy storage assemblies.

[0344] [Fig.22] represents a heat exchanger plate 13, intended to be arranged between two stacks 9 in thermal contact with them. The heat exchanger plate 13 has internal channels 53 traversed by a cooling liquid, in particular glycolated water.

[0345] The heat exchanger plate 13 has four sub-parts formed by extrusion. The heat exchanger plate 13 is made of plastic.

[0346] The heat exchanger plate 13 is welded to the two end cheeks 10 located at the front of the module 8.

[0347] A thermal paste may be placed between the heat exchanger plate 13 and the stacks 9 of cells of the module 8.

[0348] [Fig.24] represents an electrical energy storage assembly 20 comprising: - a plurality of pouch-type electric accumulator cells 50, each pouch-type cell 50, as illustrated in [Fig.27], comprising:

[0349] - a cathode and an anode enclosed in a pocket 54, - an electrical connection cathode lug 55 electrically coupled to the cathode, and - an anode 56 electrical connection tab electrically coupled to the anode, the anode 56 and cathode 55 electrical connection tabs protruding from the pocket 54,

[0350] - a cathode connector 57 and an anode connector 58 for paralleling the plurality of cells 50 of the assembly 20, the cathode 57 and anode 58 connectors each having at least one flattened portion, the cathode legs 55 each being folded onto the cathode connector 57 and the anode legs 56 each being folded onto the anode connector 58, so as to electrically connect together the cathodes of the pocket-type cells 50 on the one hand and the anodes of the pocket-type cells 50 on the other hand.

[0351] [Fig.25] shows a detail of [Fig.24] before folding the electrical connection tabs 55, 56 onto the paralleling connectors 57, 58.

[0352] The pocket 54 of each pocket-type cell 50 is flexible and takes the form of a film, as visible in [Fig.27].

[0353] The pocket 54 is made partially of electrically conductive material, for example aluminum, and is provided with an insulating coating.

[0354] The assembly comprises four pocket-type cells.

[0355] The pocket-type cells have two opposite main faces 59 connected by a slice 60.

[0356] Pocket-type cells have a rectangular parallelepiped shape.

[0357] The main faces of pocket-type cells have a length L, which can be around 514 mm. The length of the main face is understood to mean the largest dimension of the main face.

[0358] The main faces of the pocket-type cells have a width 1, which can be approximately 35.5 mm. Width is understood to mean the smallest dimension of the main faces.

[0359] The slice of the pocket-type cells has a small thickness, for example about 16 mm.

[0360] Pouch-like cells are flattened.

[0361] The slice 60 of the pocket-type cells has two large opposite faces and two small opposite faces.

[0362] The electrical connection tabs 55, 56 are of substantially rectangular shape before folding.

[0363] The two electrical connection tabs 55, 56 have the same dimensions.

[0364] The cathode electrical connection tabs have a very low thickness epc, for example 0.3 mm.

[0365] The anode electrical connection tabs have a very low thickness epa, for example 0.4 mm.

[0366] The cathode electrical connection legs 55 are made of nickel-coated copper.

[0367] The anode electrical connection tabs 56 are made of aluminum.

[0368] The electrical connection tabs 55, 56 of a pocket-type cell are located at two opposite ends of the pocket-type cell 55.

[0369] The electrical connection tabs 55, 56 are located on the edge 60 of the cells, in particular on the two smaller opposite faces of the edge.

[0370] The anode electrical connection tabs 56 are coupled to the anode by one side of width lpa.

[0371] The cathode electrical connection tabs 55 are coupled to the cathode by a side of width lpc.

[0372] The paralleling connectors, as illustrated in [Fig.26], are made of metal, for example aluminum or copper.

[0373] The two paralleling connectors 57, 58 are preferably of identical shape.

[0374] Each paralleling connector 57, 58 comprises a base portion 61 of substantially rectangular shape in top view and two branches 62 connecting perpendicularly to said base portion, substantially forming a U.

[0375] The branches 62 are of substantially rectangular shape when viewed from above.

[0376] The branches 62 have the same shape and the same dimensions.

[0377] The base portion 61 and the branches 62 are flattened and arranged so that the paralleling connector is flat.

[0378] Each electrical connection tab 55, 56 of a pocket-type cell 50 is folded onto one face of a branch 62 of a paralleling connector 57, 58.

[0379] The pocket-type cells 50 of the set 20 are arranged in pairs of consecutive cells.

[0380] Each branch 62 carries two electrical connection tabs of two consecutive cells forming a pair of cells, the cells of the pair being in particular arranged on either side of the branch 62 so that their electrical connection tabs folded on said branch come into contact. The ends of the electrical connection tabs meet.

[0381] The two consecutive cells forming a pair are arranged symmetrically.

[0382] The electrical connection tabs 55, 56 are welded after their bending, by laser, onto the paralleling connectors 57, 58.

[0383] The invention is not limited to the examples which have just been described.

[0384] The number of packs per column, modules per pack, sets per stack or cells per set may be different.

[0385] The arrangement of the rows and the control room in the enclosure may be different.

Claims

Claims

1. An electrical energy storage assembly (20) comprising: - a plurality of pouch-type electrical accumulator cells (50), each pouch-type cell (50) comprising: - a cathode and an anode enclosed in a pouch (54), - a cathode electrical connection tab (55) electrically coupled to the cathode, and - an anode electrical connection tab (56) electrically coupled to the anode, the anode and cathode electrical connection tabs (55, 56) protruding from the pouch (54), - a cathode connector (57) and an anode connector (58) for paralleling the cells of the plurality of cells of the assembly, the cathode and anode connectors (57, 58) each having at least one flattened portion, the cathode tabs (55) each being folded over the cathode connector (57) and the anode tabs (56) each being folded over the connector anodic (58),so as to electrically connect together the cathodes of the pocket-type cells (50) on the one hand and the anodes of the pocket-type cells (50) on the other hand.,

2. An electrical energy storage assembly (20) according to the preceding claim, the electrical connection tabs (55, 56) of a pocket-type cell (50) being located at two opposite ends of the pocket-type cell.

3. Electrical energy storage assembly (20) according to any one of the preceding claims, each paralleling connector (57, 58) comprising a base portion (61) of substantially rectangular shape in top view and one or more branches (62), in particular two branches, connecting, in particular perpendicularly, to said base portion (61).

4. Electrical energy storage assembly (20) according to the preceding claim, each paralleling connector (57, 58) having a comb shape, the branches (62) of the connector connecting to the base portion (61) on the same side thereof.

5. An electrical energy storage assembly (20) according to the preceding claim, each paralleling connector (57, 58) comprising two branches (62), the branches forming substantially a U with the basic portion (61).

6. An electrical energy storage assembly (20) according to any one of claims 3 to 5, each electrical connection tab (55, 56) of a pocket-type cell (50) being folded onto a face of a branch (62) of a paralleling connector (57, 58).

7. Electrical energy storage assembly (20) according to the preceding claim, each branch (62) carrying two electrical connection tabs (55, 56) of two consecutive cells forming a pair of cells, the cells (50) of the pair being in particular arranged on either side of the branch (62) so that their electrical connection tabs folded on said branch come into contact.

8. Electrical energy storage assembly (20) according to any one of the preceding claims, an interlayer (51), in particular electrically insulating, in particular made of foam, being arranged between two consecutive cells.

9. Electrical energy storage assembly (20) according to any one of the preceding claims, the electrical connection tabs (55, 56) being welded after their bending, in particular by laser, onto the paralleling connectors (57, 58).

10. Stack of electric accumulator cells (9), comprising several assemblies (20) for storing electrical energy according to any one of the preceding claims and two end cheeks (10, 11) between which the assemblies (20) for storing electrical energy are arranged.

11. Stack of electric accumulator cells (9) according to the preceding claim, an interlayer (51) being arranged between an end cheek (10, 11) and a cell (50) adjacent to the end cheek.

12. Stack of electric accumulator cells (9) according to one of the two preceding claims, the end cheeks (10, 11) being held clamped by at least one clamping element (49), each end cheek (10, 11) having in particular at least one notch (52) for receiving the clamping element (49).

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