Set of electrochemical elements with optimized current flow and associated battery

Abstract

Set of electrochemical elements with optimized current flow and associated battery The set comprises blocks (18) of electrochemical elements (12) electrically connected in series as follows: - the blocks (18) of the i-th row (16) of K columns (14) are electrically connected to each other in series, the blocks (18) of the i-th row forming an i-th group (22) of blocks (18) of electrochemical elements (12) of the i-th row; - for each i-th row, each block (18) of said row of columns (14) is electrically connected with the block(s) (18) of said i-th row of the adjacent electrochemical column(s) (14) by first power electrical connections (20) linking in series respectively the M electrochemical elements (12) of said block (18) with respectively the M electrochemical elements (12) of the block(s) of said row of the adjacent electrochemical column(s) (14).Figure for the abbreviation: figure 2.

Description

Title of the invention: Set of electrochemical elements with optimized current flow and associated battery

[0001] The present invention relates to an assembly comprising K columns of electrochemical elements arranged laterally next to each other in a transverse direction, K being a natural number, each column extending longitudinally in a longitudinal direction, each column comprising L blocks of electrochemical elements arranged longitudinally one after the other in respectively L line(s) of electrochemical elements, L being a natural number, each block of electrochemical elements comprising M electrochemical elements, M being a natural number, M electrochemical elements of each block of electrochemical elements being electrically connected to each other in parallel by balancing electrical connections.

[0002] A set comprising several columns having blocks of electrochemical elements electrically connected in series with each other is known from patent application EP 3 123 539, the columns themselves being electrically connected in series with each other.

[0003] Generally, the electrochemical elements of the electrochemical element blocks are arranged in rows on their large face. Then, depending on the desired configuration, the electrochemical elements of each electrochemical element block are connected to each other in parallel, then the electrochemical element blocks are connected to each other in series by collecting and transferring connections, and finally the columns are connected to each other in series to form electrochemical assemblies with different configurations of the type xPyS, where x and y are natural numbers. The digit x indicates the number of electrochemical elements connected in parallel, and the digit y indicates the number of element blocks connected in series.

[0004] This structure has several drawbacks. Some power connections for the electrochemical element blocks must be oversized when x is greater than 1. For example, in a 5P2S arrangement, due to the 5P configuration, the power connections for the electrochemical element blocks must be oversized for five times the current flowing through each electrochemical element in the block. This is because the power connections must allow the passage of the sum of the currents flowing through each of the electrochemical elements in the block. When this oversizing is not possible, for example for reasons In addition to their bulk, these power connections generate significant heat during use.

[0005] Also, in the event of a malfunction of a cell in a block of electrochemical elements, the cells in parallel with the malfunctioning cell may experience an external short circuit. The short-circuit current then flows through the power supply connections which, if they are oversized, are incompatible with an electrical fuse function intended to isolate the faulty cell.

[0006] An object of the invention is to propose a set of electrochemical elements that are simple to produce, while exhibiting reduced heating during use and in which the isolation of a faulty electrochemical element is easy.

[0007] To this end, the invention relates to an assembly of the aforementioned type, characterized in that the K x L blocks of electrochemical elements are electrically connected to each other in series as follows:

[0008] for each i-th row, the blocks of electrochemical elements in the i-th row of the K columns are electrically connected to each other in series, the blocks of electrochemical elements in the i-th row forming an i-th group of blocks of electrochemical elements in the i-th row,

[0009] for each i-th row, each block of electrochemical elements of said row of the K columns being electrically connected with the block(s) of electrochemical elements of said i-th row of the adjacent electrochemical column(s) by first power electrical connections linking in series respectively the M electrochemical elements of said block of electrochemical elements with respectively the M electrochemical elements of the block(s) of electrochemical elements of said row of the adjacent electrochemical column(s).

[0010] With such an arrangement, the power electrical connections do not need to be oversized to allow the passage of a current greater than that supplied by a single electrochemical element, and they heat up less than in the prior art. The balancing electrical connections nevertheless ensure adequate electrical balancing within each block of parallel electrochemical elements by separating the power electrical currents flowing through the power electrical connections from the balancing electrical currents flowing through the balancing electrical connections.

[0011] Furthermore, thanks to this configuration, it is possible to isolate a faulty electrochemical element from a block of electrochemical elements easily and spontaneously. This is the case without having to isolate the other electrochemical elements of the same block of electrochemical elements with it, thanks to the presence of the balancing electrical connections that may be undersized compared to power electrical connections.

[0012] According to other advantageous aspects of the invention, the assembly comprises one or more of the following features, taken individually or in all technically possible combinations:

[0013] - each electrical power connection is made by at least one wire of electrically conductive material between terminals of electrochemical elements of adjacent blocks of electrochemical elements along the i-th line;

[0014] - each electrical balancing connection is sized to receive a balancing electric current with a maximum intensity at least five times lower than the operating electric current intensity delivered by the assembly;

[0015] - the electrical balancing connection is designed to break by melting when a current of higher intensity than the maximum intensity flows through the balancing electrical connection;

[0016] - for each i-th line, the balancing electrical connections link electrically in parallel each of the M electrochemical elements of each block of electrochemical elements of said line with each other;

[0017] - the electrical balancing connections are made by at least one wire of electrically conductive material between terminals of electrochemical elements of blocks of electrochemical elements longitudinally adjacent along each block of electrochemical elements;

[0018] - L is a natural number greater than or equal to 2, the L groups of blocks of elements of The lines being electrically connected to each other in series;

[0019] - the first group of electrochemical element blocks of the first row is electrically connected in series to the second group of electrochemical element blocks of the second line by electrically connecting in series a last electrochemical element block of the first group along a first lateral edge of the assembly with a first electrochemical element block of the second group along the first lateral edge of the assembly;

[0020] - for j ranging from 2 to L1, the j-th group of blocks of electrochemical elements of the The jth line is electrically connected in series:

[0021] - at the j- 1-th group of electrochemical element blocks of the j- 1-th row by electrical series connection of a first block of electrochemical elements of the jth group along the first lateral edge of the assembly with a last block (18) of electrochemical elements of the jlth group along the first lateral edge of the assembly; and

[0022] - at the j+l-th group of blocks of electrochemical elements of the j+l-th row by electrically connecting in series a final block of electrochemical elements of the j- th group along a second lateral edge of the set, opposite the first lateral edge of the set, with a first block of electrochemical elements of the j+l-th group along the second lateral edge of the set;

[0023] - the L-th group of electrochemical element blocks of the L-th row is electrically connected in series to the 11th group of electrochemical element blocks of the 11th line by series electrical connection:

[0024] - of a first block of electrochemical elements of the L-th group along the first lateral edge of the whole with a final block of electrochemical elements of the 11th group along the first lateral edge of the whole; or

[0025] - of a first block of electrochemical elements of the L-th group along the second lateral edge of the set with a final block of electrochemical elements of the 11th group along the second lateral edge of the set.

[0026] - the electrical connection between a first and a last block of elements electrochemical along the first lateral edge of the assembly or along the second lateral edge of the assembly on two adjacent lines is achieved by an electrical transfer connection, the electrical transfer connections electrically linking the M electrochemical elements of the first block of electrochemical elements with the M electrochemical elements of the last block of electrochemical elements;

[0027] - for each of the first block and the last block, the M electrochemical elements the block are connected together in parallel by an electrical collection connection extending along the first lateral edge of the assembly or along the second lateral edge of the assembly;

[0028] - electrical collection connections and / or electrical transfer connections are made by at least one wire of electrically conductive material;

[0029] - M is greater than or equal to 2, in particular equal to 5;

[0030] - L is greater than or equal to 1, in particular equal to 3;

[0031] - each electrochemical element has a substantially prismatic shape defining two large parallel faces, each block of electrochemical elements having an substantially rectangular parallelepiped shape, the blocks of electrochemical elements in each column being arranged so that small faces of the parallelepiped of two adjacent blocks of electrochemical elements are directed towards each other and are in a plane perpendicular to the longitudinal direction, the electrochemical elements of each block of electrochemical elements being arranged so that the large faces of the prisms of said electrochemical elements are parallel to the small faces of the parallelepiped of the corresponding block of electrochemical elements;

[0032] - it further comprises terminal terminals intended to provide between them a electrical power, the terminals being electrically connected in series respectively to a first block and a last block among the K x L blocks of electrochemical elements connected together in series.

[0033] - each column comprises a longitudinally extending frame, the L blocks of electrochemical elements being arranged longitudinally one after the other in respectively L lines of the chassis.

[0034] The invention also relates to a battery comprising at least one set as defined above.

[0035] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0036] [Fig-1] [Fig. 1] is a partial perspective view of a first assembly according to the invention, intended to be placed in a battery, the assembly comprising a plurality of columns formed of blocks of electrochemical elements, in which the direction of the power electric current lines is transverse, the direction of the balancing current lines being longitudinal;

[0037] [Fig.2] [Fig.2] is a partial perspective view of the first assembly according to the invention, illustrating the electrical power connections between adjacent blocks of a line of blocks, the electrical connections for collecting and transferring power, along a lateral edge of the assembly and the electrical balancing connections, between successive electrochemical elements of the columns, with connections in the form of metallic wires;

[0038] [Fig.3] [Fig.3] is a partial perspective view of a second assembly according to the invention, in which the electrical connection for collection and transfer located along the lateral edge for connecting two adjacent block lines in series is formed from a metal bar;

[0039] [Fig.4] [Fig.4] is a partial perspective view of a third assembly according to the invention in which the electrical power connection between two adjacent electrochemical elements of two transversely adjacent blocks is formed by a metallic tab;

[0040] [Fig. 5] [Fig. 5] is a partial perspective view of a fourth assembly according to the invention in which the collection and transfer connection comprises offset connectors;

[0041] [Fig.6] [Fig.6] is an electrical diagram of part of an assembly according to the invention, during an abusive event occurring within an electrochemical element of a block.

[0042] Figures 1 and 2 illustrate a first set 10 of electrochemical elements 12 according to the invention, intended to be received in a battery (not shown).

[0043] The battery generally comprises at least one set 10, generally several sets 10 arranged side by side and / or one on top of the other, and at least one case (not shown) containing one or more sets 10. Each case allows the joint support and movement of all the electrochemical elements 12 of the or each set 10 which it contains.

[0044] The set 10 illustrated in figures 1 and 2 comprises K columns 14 arranged laterally next to each other along a transverse direction DT of the set 10, K being a natural number, each column 14 extending longitudinally along a longitudinal direction DL of the set 10.

[0045] Each column 14 advantageously comprises a chassis (not shown) extending longitudinally and L blocks 18 of electrochemical elements 12 arranged one after the other along the longitudinal direction DL in respectively L rows 16, L being a natural number.

[0046] Each block 18 of electrochemical elements 12 comprises M electrochemical elements 12 connected in parallel, M being a natural number.

[0047] The assembly 10 comprises, for i from 1 to L, electrical power connections 20 (visible on the [Fig.2]) for connecting in series the blocks 18 of electrochemical elements 12 of the i-th row 16 of the K columns 14, the blocks 18 of electrochemical elements 12 of the i-th row 16 forming an i-th group 22 of blocks 18 of electrochemical elements 12 of the i-th row.

[0048] The assembly 10 further comprises, along the lateral edges 24A, 24B of the assembly 10, electrical collection connections 26 (visible in [Fig.2]) for collecting the electrical power current generated within each group 22 of blocks 18 of electrochemical elements 12 electrically connected together in series on a line 16, and electrical transfer connections 27 (visible in [Fig.2]) for transferring the electrical current collected by the electrical collection connections 26 from one group 22 of blocks of electrochemical elements 12 on a line 16 to another group 22 of blocks of electrochemical elements 12 on another line 16, preferably longitudinally adjacent.

[0049] The term "electrical collection connection" here generally refers to an electrical connection which connects in parallel the electrochemical elements 12 of a block 18 located along a lateral edge 24A, 24B of the assembly 10 and which thus collects all the electrical power currents generated in the alignments of electrochemical elements 12 connected in series of the blocks 18 located on the same line 16.

[0050] The term "electrical transfer connection" here generally refers to a series electrical connection between a group 22 of blocks of electrochemical elements 12 on a line 16 and another group 22 of blocks of electrochemical elements 12 on another line 16.

[0051] In the example of [Fig.2], the electrical collection connections 26 are made by conductive elements separate from the conductive elements making the electrical transfer connections 27.

[0052] In other examples, which will be described below, the electrical collection connections 26 and the electrical transfer connections 27 are made by the same conductive element.

[0053] The assembly 10 finally includes balancing electrical connections 28 (visible on [Fig.2]), to connect in parallel the M electrochemical elements 12 of each block 18 of electrochemical elements 12.

[0054] With reference to [Fig.1], the assembly 10 further comprises terminal terminals 29A, 29B, intended to supply electrical power between them during the discharge of the assembly 10 or to receive electrical power between them during the recharging of the assembly 10.

[0055] Each terminal terminal 29A, 29B is electrically connected in series respectively to a first block 18 and to a last block 18 among the K x L blocks 18 of electrochemical elements 12, connected together in series in the assembly 10.

[0056] The term "first" and the term "last" are understood here and generally in all that follows, with respect to the direction of flow of an electric current of electric power delivered by the assembly 10 between the terminals 29A, 29B.

[0057] In the example illustrated in particular by [Fig.1], the number K of columns is equal to 2, the number of rows L is equal to 3 and the number M of electrochemical elements 12 per block 18 is equal to 5.

[0058] More generally, the number M of electrochemical elements 12 per block 18 is greater than or equal to 2, in particular less than 12. The number of rows L is greater than or equal to 1. The number of columns K is greater than 2.

[0059] As can be seen in [Fig. 2], each electrochemical cell 12 is here a prismatic element comprising a container 30 delimiting an internal volume containing alternating anodes, internal separators, and cathodes, and an electrolyte (not shown). The electrochemical cell 12 is, for example, of the lithium-ion type or of the alkali electrolyte type.

[0060] The electrochemical element 12 further comprises a cover 32 closing the inner volume and carrying, on either side transversely, a terminal 34A of first polarity and a terminal 34B of second polarity.

[0061] The container 30 defines two large faces 36 extending in a plane perpendicular to the longitudinal direction DL, and two small faces 38 extending in a plane perpendicular to the transverse direction DT.

[0062] Each block 18 of electrochemical elements 12 has M electrochemical elements 12 stacked longitudinally. Each electrochemical element 12 of block 18 has a large face 36, or two large faces 36 located respectively opposite and preferably in contact with a large face 36 of an electrochemical element 12 longitudinally adjacent to block 18.

[0063] Each block 18 of electrochemical elements 12 has a substantially rectangular parallelepiped shape, with large faces 40 formed from the succession of small faces 38 of the electrochemical elements 12 of the block 18 and with small faces 42 formed from the large faces 36 of the electrochemical elements 12 located at the longitudinal ends of the block 18.

[0064] The blocks 18 of electrochemical elements 12 in each column 14 are advantageously arranged in the chassis, such that small faces 42 of the parallelepiped of two longitudinally adjacent blocks 18 of electrochemical elements 12 are directed towards each other and in a plane perpendicular to the longitudinal direction DL

[0065] The large faces 36 of the electrochemical elements 12 are parallel to the small faces 42 of the parallelepiped of the block 18 of electrochemical elements 12 and perpendicular to the longitudinal direction DL.

[0066] In each row 16, within a group 22 of blocks 18, the M electrochemical elements 12 of block 18 on a column 14 are located transversely adjacent respectively to the M electrochemical elements 12 of the adjacent block 18 located on an adjacent column 14.

[0067] Thus, the small faces 38 of the electrochemical elements 12 of a block 18 on a column 14 forming a large face 40 of the block 18, are located opposite and advantageously in contact with the small faces 38 of the electrochemical elements 12 forming the large face 40 of a block 18 transversely adjacent on an adjacent column 14.

[0068] Thus, each group 22 of blocks 18 within each line 16 comprises M successive transverse alignments of transversely adjacent electrochemical elements 18.

[0069] Within each block 18, the first polarity terminals 34A are located on the same side of the electrochemical elements 12 of the block 18, preferably opposite each other along the longitudinal direction DL. The second polarity terminals 34B are located on the same opposite side of the electrochemical elements 12 of the block 18, preferably opposite each other along the longitudinal direction DL.

[0070] Along a row 16 within a group 22, the first polarity terminals 34A of a block 18 of a column 14 are located adjacent to the second polarity terminals 34B of a block 18 transversely adjacent on an adjacent column 16.

[0071] Similarly, along a column 14, the first polarity terminals 34A of a block 18 of the column 14 are located adjacent to the second polarity terminals 34B of a block 18 longitudinally adjacent along the column 14.

[0072] With reference to [Fig.2], each electrical power connection 20 connects in series an electrochemical element 12 of a block 18 of a column 14 to an electrochemical element 12 transversely adjacent on the same transverse alignment, the adjacent electrochemical element 12 being part of a block 18 transversely adjacent on an adjacent column 14.

[0073] For this purpose, each power electrical connection 20 connects a first polarity terminal 34A on the electrochemical element 12 of the block 18 to a second polarity terminal 34B on the transversely adjacent block 18.

[0074] In the example illustrated by [Fig.2], each electrical power connection 20 comprises at least one wire 50 of electrically conductive material, advantageously several parallel wires 50 of electrically conductive material, in particular between 2 and 8 wires 50.

[0075] Each wire 50 is formed exclusively of electrically conductive material, without including an electrically insulating sheath.

[0076] The electrically conductive material is, for example, copper, aluminum, or an alloy comprising at least copper or aluminum.

[0077] More generally, an electrically conductive material intended to form the wire 50 has an electrical conductivity advantageously greater than 0.1 MS / cm.

[0078] The wire 50 has a thickness of less than 0.5 mm and in particular between 50 pm and 400 pm.

[0079] It can be fixed to terminals 34A, 34B in a "wire bonding" operation.

[0080] The wire 50 is for example fixed by welding, in particular by ultrasound, by locally heating the wire and / or the terminals 34A, 34B and deploying it between the terminals 34A, 34B using a wire 50 deployment head. This is fast, precise and minimizes mechanical stress on the wire 50 and the terminals 34A, 34B.

[0081] The successive power electrical connections 20 in series of the electrochemical elements 12 along each transverse alignment, in each group 22 of blocks 18 of electrochemical elements 12 corresponding to the successive lines 16, create transverse circulation segments 52 of a power electric current within the assembly 10, visible on the [Fig.1], along the transverse direction DT.

[0082] As can be seen in [Fig. 1], the transverse segment 52 in a first group 22 of blocks 18 of electrochemical elements 12 along a first line 16 is oriented in a first direction along the transverse direction DT, opposite to the second direction of orientation of the transverse segment 52 in a second group 22 of blocks 18 of electrochemical elements 12 adjacent to the first group 22 along a second line 16.

[0083] The electrical collection and transfer connections 26 are located along the last blocks 18 or the first blocks 18 of each group 22 of blocks 18 defining the lateral edges 24A, 24B of the assembly 10.

[0084] In each last block 18 or in each first block 18 along a lateral edge 24A, the successive terminals 34A, 34B facing longitudinally the M electrochemical elements 12 of the block 18 are connected to each other to place the M electrochemical elements 12 in parallel and collect the electric power currents generated in each transverse alignment of electrochemical elements 12, in order to transmit the electric power current resulting from the sum of the collected electric power currents to a group 22 of adjacent blocks 18.

[0085] For this purpose, an electrical collection connection 26 connects each terminal 34A, 34B of an electrochemical element 12 to the terminal 34A, 34B of the same polarity of the electrochemical element 12 longitudinally adjacent within the same block 18.

[0086] The intensity of the collected power electric current increasing successively by moving longitudinally along the lateral edge 24A towards the group 22 of adjacent blocks 18 to which the power electric current is transmitted, the maximum intensity supported by each electrical collection connection 26 also increases along the lateral edge 24A.

[0087] In the example of [Fig.2], each electrical collection connection 26 also includes at least one wire 50 of electrically conductive material.

[0088] The number of wires 50 of each electrical collection connection 26 therefore increases along the lateral edge 24A, towards the group 22 of blocks 18 to which the power electrical current is transferred in order to accommodate the increasing intensity of the collected current.

[0089] On the contrary, in the group 22 of blocks 18 to which the power electric current has been transferred, the number of wires 50 of each electrical collection and transfer connection 26 decreases along the lateral edge 24A away from the group of blocks that transmitted the power electric current.

[0090] Such an arrangement reduces the weight of the assembly 10, since each electrical collection connection 26 is adapted to the intensity of the power electric current it receives.

[0091] For the series connection of groups 22 of blocks 18 of successive lines 16, an electrical transfer connection 27 connects in series the group 22 of blocks 18 of electrochemical elements 12 of the first line 16 to the second group 22 of blocks 18 of electrochemical elements 12 of the second line 16, by connection electrical in series of a last block 18 of electrochemical elements of the first group 22 along the first lateral edge 24A with a first block 18 of electrochemical elements 12 of the second group 22 along the first lateral edge 24A of the set 10.

[0092] For each jth line 16 going from 2 to L1, at least one electrical transfer connection 27 connects the jth group 22 of blocks 18 of electrochemical elements of the jth line 16 in series:

[0093] - to the j1st group 22 of blocks 18 of electrochemical elements 12 of the j1st line 16 by electrically connecting in series a terminal 34A, 34B of a first electrochemical element 12 of a first block 18 of electrochemical elements 12 of the jth group 22 along the first lateral edge 24A of the assembly 10 with a terminal 34B, 34A of opposite polarity of a last electrochemical element 12 of a last block 18 of electrochemical elements 12 of the jth group 22 along the first lateral edge 24A; and

[0094] - at the j+l-th group 22 of blocks 18 of electrochemical elements 22 of the j+l-th line 16 by electrical connection in series of a terminal 34A, 34B of a last electrochemical element 12 of a last block 18 of electrochemical elements 12 of the j-th group along a second lateral edge 24B of the set 10 opposite to the first lateral edge 24A of the set 10 with a terminal 34B, 34A of opposite polarity of a first electrochemical element 12 of a first block 18 of electrochemical elements 12 of the j+l-th group 22 along the second lateral edge 24B of the set 10.

[0095] For the L-th line 16, at least one electrical transfer connection 27 connects the L-th group 22 of blocks 18 of electrochemical elements 22 of the L-th line 16 in series to the L-th group 22 of blocks 18 of electrochemical elements 12 of the L-th line 16.

[0096] This electrical transfer connection 27 connects in series:

[0097] - a terminal 34A, 34B of a first electrochemical element 12 of a first block 18 of electrochemical elements 12 of the Lth group 22 along the first lateral edge 24A of the set 10 with a terminal 34B, 34A of opposite polarity of a last electrochemical element 12 of a last block 18 of electrochemical elements 12 of the L1th group along the first lateral edge 24A of the set 10; or

[0098] - a terminal 34A, 34B of a first electrochemical element 12 of a first block 18 of electrochemical elements 12 of the Lth group along the second lateral edge 24B of the set with a terminal 34B, 34A of opposite polarity of a last electrochemical element 12 of a last block 18 of electrochemical elements of the Llth group 22 along the second lateral edge 24B of the set 10.

[0099] In the example of [Fig.2], each electrical transfer connection 27 also includes at least one wire 50 of electrically conductive material, here several wires 50.

[0100] The electrical transfer connections 27, which ensure the transfer of electrical power between the groups 22 of successive blocks 18 along the longitudinal direction DL, receive an electrical current of maximum intensity. The number of wires 50 in each electrical transfer connection 27 is therefore advantageously greater than or equal to the maximum number of wires 50 in each electrical collection connection 26 within each block 18.

[0101] The electrical collection connections 26 and the electrical transfer connections 27 thus ensure the collection of the electric power current flowing along the transverse segments 52 and its transfer from one transverse segment 52 to the other, alternately along the first lateral edge 24A and along the second lateral edge 24B to make the electric power current follow a creeping ladder path between the terminals 29A, 29B of the assembly 10, as seen in [Fig.1].

[0102] For each block 18 in each row 16, the balancing electrical connections 28 electrically connect in parallel each of the M electrochemical elements 12 of the block 18 together.

[0103] Thus, at least the terminals 34A of the same polarity of the M electrochemical elements 12 of the block 18 are connected two by two longitudinally by an electrical balancing connection 28, in particular in parallel with the electrical power connections 20 which connect the terminals 34A of the same polarity of each of the M electrochemical elements 12 of the block 18 to the terminals 34B of opposite polarity of the adjacent M electrochemical elements 12 on each alignment of an adjacent block 18 on the same line 16.

[0104] The balancing electrical connections 28 create circulation paths 60 for the balancing electrical currents within each block 18, which extend parallel to the longitudinal direction DL. These paths 60 are not parallel to the circulation segments 52 of the power electrical current.

[0105] Advantageously, as illustrated in [Fig.2], balancing electrical connections 28 also electrically connect the opposite polarity terminals 34B of the adjacent M electrochemical elements 12 in parallel.

[0106] This ensures redundancy of balancing current flow on both sides of the power electrical connections 20 in the event that a failure of a balancing electrical connection 28 occurs.

[0107] Thus, a reliable capacity to measure the electrical voltage across terminals 34A, 34B of each electrochemical element 12 is ensured.

[0108] In the example of [Fig.2], the balancing electrical connections 28 are made by at least one wire of electrically conductive material 50 as described above.

[0109] Each balancing electrical connection 28 is sized to receive a balancing electrical current of maximum intensity at least five times lower than the intensity of the operating electrical current delivered by the assembly 10 between the terminals 29A, 29B.

[0110] Thus, in the event of a significant increase in the balancing electrical current, for example resulting from an abuse event within an electrochemical element 12A (see [Fig.6]), the balancing electrical connection 28 is configured to break, in particular by melting, to electrically isolate the electrochemical element 12A undergoing the abuse event from the other blocks 18 of the same group 22, as will be described below.

[0111] The operation of assembly 10 when delivering electrical power to terminals 29A, 29B will now be described.

[0112] A power electric current is generated within each alignment of electrochemical elements 12 of each group 22 of blocks 18 within each line 16. The power electric current flows transversely from one electrochemical element 12 to another through the power electrical connections 20. The power electric currents are then collected and accumulated by the collection electrical connections 26, along the lateral edges 24A, 24B of the assembly 10.

[0113] The resulting electric power current is then transmitted from a group 22 of blocks 18 along a line 16 to the group 22 of blocks 18 along the adjacent line 16, via the electrical transfer connections 27. The electric power current thus follows a creeping ladder path within the assembly 10, as illustrated by [Fig.1] (arrows 52).

[0114] Simultaneously, balancing electric currents flow longitudinally between the electrochemical elements 12 mounted in parallel within the same block 18 (arrows 60).

[0115] With reference to [Fig.6], when an electrochemical element 12A within a block 18A along a line 16 undergoes an abuse event, it becomes equivalent to an electrical resistance creating a short circuit 70 through which the power electrical current of the electrochemical elements 12A1, 12A2 of the block 18A flows, with a short-circuit current SC, through the balancing electrical connections 28A.

[0116] However, since the 28A balancing electrical connections are sized to receive a maximum electrical current at least five times lower than the operating electrical current delivered by the assembly 10, they function like fuses that break and open the 28A balancing electrical connections along the 18A block.

[0117] The short-circuit electric current, with a reduced intensity SC / 5, is then transferred into the balancing electrical connections 28B of the adjacent blocks 18B on the same line 16, possibly causing the balancing electrical connections 28B to break if the current SC / 5 remains greater than the maximum intensity supported by the balancing electrical connections 28B.

[0118] Then, this phenomenon is repeated in the balancing electrical connections 28C of the blocks 18C adjacent to the blocks 18B with a reduced current SC / 9, until the short-circuit current becomes less than the maximum current causing the balancing electrical connections 28 to break.

[0119] This automatic reduction of the currents involved in the abusive event therefore prevents significant heating of the electrochemical elements 12 that are subjected to it. This prevents or greatly limits the risk of a chain reaction that could occur in a classic xPyS type architecture, in which the power currents flowing between the electrochemical elements 12 are not separated from the balancing currents of the electrochemical elements.

[0120] The dissociation between, on the one hand, the power electrical currents which follow the transverse segments 52 along the groups 22 of blocks 18 through the power electrical connections 20, and through the collection electrical connections 26 and transmission electrical connections 27, and on the other hand, the balancing electrical currents which follow the longitudinal circulation paths 60 is therefore very advantageous.

[0121] It allows for adequate sizing of the electrical collection connections 26 by adapting to the collected current, and the use of balancing electrical connections 28 of small cross-sections, reducing the weight and size of the assembly 10. This is permitted while allowing reliable voltage measurement of the blocks 18 of electrochemical elements 12 in parallel, in normal operation, while limiting the intensity of the short-circuit electrical currents flowing in the electrochemical element 12 undergoing the abusive event.

[0122] The second assembly 10 according to the invention, illustrated in [Fig.3], differs from that illustrated in [Fig.2] by the realization of the electrical collection connections 26 and the electrical transfer connection 27 between two groups 22 of longitudinally adjacent blocks 18 by a bar 80 of a single conductive material, placed along a lateral edge 24A, 24B.

[0123] The bar 80 is dimensioned to support, over its entire length, the maximum intensity of the electric power current collected in one of the groups 22 of blocks 18 and transmitted to the longitudinally adjacent group 22 of blocks 18.

[0124] The third assembly 10 according to the invention, illustrated in [Fig.4], differs from that illustrated in [Fig.2] by the realization of each electrical power connection 20 in the form of a tab 82 in conductive material connecting the terminals of opposite polarities 34A, 34B of two adjacent electrochemical elements 12 in the same alignment, between two blocks 18 of a group 22 on the same line 16.

[0125] The fourth assembly 10 according to the invention, illustrated in [Fig.5], differs from that illustrated in [Fig.2] in that it comprises along each lateral edge 24A, 24B, between two longitudinally adjacent groups 22 of blocks 18, several electrical collection and transfer connections 26, 27 selectively connecting certain alignments of electrochemical elements 12 of a group 22 of blocks 18 along a line 16 with certain alignments of electrochemical elements 12 of a group 22 of blocks 18 along an adjacent line 16.

[0126] For example, a first set Al among the alignments of electrochemical elements 12 of a group 22 of blocks 18 along a line 16 are connected to a first set Ala of electrochemical elements 12 of an adjacent group 22 of blocks 18 along an adjacent line 16 by a first comb 90 for collecting and transferring an electric power current, without being electrically connected to the alignments A2, A3, A3a located between the alignments of the first sets Al, Ala.

[0127] A second set A2 among the alignments of electrochemical elements 12 of a group 22 of blocks 18 along a line 16 are connected to a second set A2a of electrochemical elements 12 of an adjacent group 22 of blocks 18 along an adjacent line 16 by a second comb 92 for collecting and transferring an electric power current, without being electrically connected to the alignments A3, A3a, Ala located between the alignments of the second sets A2, A2a, in particular the alignments of the first set Ala.

[0128] The longitudinally adjacent alignments A3 and A3a of a group 22 of blocks 18 along a line 16 and of an adjacent group 22 of blocks 18 along an adjacent line 16 are connected to each other directly by a connecting tab 94.

Claims

1. Demands An assembly (10) comprising K columns (14) of electrochemical elements (12) arranged laterally side by side in a transverse direction (DT), K being a natural number, each column (14) extending longitudinally in a longitudinal direction (DL), each column (14) comprising L blocks (18) of electrochemical elements (12) arranged longitudinally one after the other in L row(s) of electrochemical elements respectively, L being a natural number, each block (18) of electrochemical elements (12) comprising M electrochemical elements (12), M being a natural number, the M electrochemical elements (12) of each block (18) of electrochemical elements (12) being electrically connected to each other in parallel by balancing electrical connections (28), characterized in that the K x L blocks (18) of electrochemical elements (12) are electrically connected to each other in series as follows: for each i-th line,the blocks (18) of electrochemical elements (12) of the i-th row of the K columns (14) are electrically connected to each other in series, the blocks (18) of electrochemical elements (12) of the i-th row forming an i-th group (22) of blocks (18) of electrochemical elements (12) of the i-th row, for each i-th row, each block (18) of electrochemical elements (12) of said row of the K columns (14) being electrically connected with the block(s) of electrochemical elements (12) of said i-th row of the adjacent electrochemical column(s) (14) by first power electrical connections (20) respectively linking in series the M electrochemical elements (12) of said block (18) of electrochemical elements (12) with respectively the M electrochemical elements (12) of the block(s) of electrochemical elements (12) of the said line of the adjacent electrochemical column(s) (14),in that each electrical balancing connection (28) is sized to receive a balancing electrical current of maximum intensity at least five times lower, to the intensity of the operating electric current delivered by the assembly (10) and in that the balancing electrical connection (28) is intended to break by melting when a current of intensity greater than the maximum intensity flows through the balancing electrical connection (28).

2. Assembly (10) according to claim 1, wherein each electrical power connection (20) is made by at least one wire of electrically conductive material between terminals (34A, 34B) of the electrochemical elements (12) of the blocks (18) of electrochemical elements (12) adjacent along the i-th line.

3. Assembly (10) according to any one of the preceding claims, wherein for each i-th line, the balancing electrical connections (28) electrically connect in parallel each of the M electrochemical elements (12) of each block (18) of electrochemical elements (12) of said line together.

4. Assembly (10) according to any one of the preceding claims, wherein the electrical balancing connections (28) are made by at least one wire of electrically conductive material between terminals (34A, 34B) of the electrochemical elements (12) of the blocks (18) of electrochemical elements (12) longitudinally adjacent along each block (18) of electrochemical elements (12).

5. Assembly (10) according to any one of the preceding claims, wherein L is a natural number greater than or equal to 2, the L groups (22) of blocks (18) of elements of the L lines being electrically connected to each other in series,

6. Assembly (10) according to claim 5, wherein: - the first group (22) of blocks (18) of electrochemical elements (12) of the first row is electrically connected in series to the second group (22) of blocks (18) of electrochemical elements (12) of the second row by electrically connecting in series a last block (18) of electrochemical elements (12) of the first group (22) along a first lateral edge (24A) of the assembly (10) with a first block (18) of electrochemical elements (12) of the second group along the first lateral edge (24A) of the assembly (10);

7. - for j ranging from 2 to L1, the jth group (22) of blocks (18) of electrochemical elements (12) of the jth row is electrically connected in series: - to the jth group (22) of blocks (18) of electrochemical elements (12) of the jth line by electrical series connection of a first block (18) of electrochemical elements (12) of the jth group along the first lateral edge (24A) of the assembly (10) with a last block (18) of electrochemical elements (12) of the jth group (22) along the first lateral edge (24A) of the assembly (10); and - to the j+l-th group (22) of blocks (18) of electrochemical elements (12) of the j+l-th line by electrical connection in series of a last block (18) of electrochemical elements (12) of the j-th group along a second lateral edge (24B) of the set (10), opposite the first lateral edge (24A) of the set (10), with a first block (18) of electrochemical elements (12) of the j+l-th group along the second lateral edge (24B) of the set (10); - the Lth group (22) of blocks (18) of electrochemical elements (12) of the Lth line is electrically connected in series to the L1st group (22) of blocks (18) of electrochemical elements (12) of the L1st line by electrical series connection: - of a first block (18) of electrochemical elements (12) of the L-th group along the first lateral edge (24A) of the assembly (10) with a last block (18) of electrochemical elements (12) of the L-th group along the first lateral edge (24A) of the assembly (10); or - of a first block (18) of electrochemical elements (12) of the L-th group along the second lateral edge (24B) of the assembly (10) with a last block (18) of electrochemical elements (12) of the L-th group along the second lateral edge (24B) of the assembly (10). Assembly (10) according to claim 6, wherein the electrical connection between a first and a last block (18) of electrochemical elements (12) along the first lateral edge (24A) of the assembly (10) or along the second lateral edge (24B) of the assembly (10) on two adjacent lines is made by an electrical transfer connection (27), the electrical transfer connections (27) electrically linking the M electrochemical elements (12) of the first block (18) of electrochemical elements (12) with the M electrochemical elements (12) of the last block (18) of electrochemical elements (12).

8. Assembly (10) according to claim 7, wherein, for each of the first block (18) and the last block (18) the M electrochemical elements (12) of the block (18) are connected together in parallel by an electrical collection connection (26) extending along the first lateral edge (24A) of the assembly (10) or along the second lateral edge (24B) of the assembly (10).

9. Assembly (10) according to claim 8 or 9, wherein the electrical collection connections (27) and / or the electrical transfer connections (26) are made by at least one wire of electrically conductive material.

10. Assembly (10) according to any one of the preceding claims, wherein M is greater than or equal to 2, in particular equal to 5

11. Assembly (10) according to any one of the preceding claims, wherein L is greater than or equal to 1, in particular equal to 3

12. d J. Assembly (10) according to any one of the preceding claims, wherein each electrochemical element (12) has a substantially prismatic shape defining two large parallel faces (36), each block (18) of electrochemical elements (12) having a substantially rectangular parallelepiped shape, the blocks (18) of electrochemical elements (12) of each column (14) being arranged so that small faces (42) of the parallelepiped of two adjacent blocks (18) of electrochemical elements (12) are directed towards each other and are in a plane perpendicular to the longitudinal direction (DL), the electrochemical elements (12) of each block (18) of electrochemical elements (12) being arranged so that the large faces (36) of the prisms of said electrochemical elements (12) are parallel to the small faces (42) of the parallelepiped of the block (18) of corresponding electrochemical elements (12).

13. Assembly (10) according to any one of the preceding claims, further comprising terminals (29A, 29B) for supplying electrical power to each other, the terminals (29A, 29B) being electrically connected in series 20 respectively to a first block (18) and to a last block (18) among the K x L blocks (18) of electrochemical elements (12) connected together in series.

14. Battery, comprising at least one set (10) according to any one of the preceding claims.

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