In particular, battery cell blocks for autonomous vehicles

Abstract

The battery cell block (10) comprises a plurality of juxtaposed flexible actuators (1), each flexible actuator (1) having two tabs positioned on either side in the plane of the accumulator and forming electrodes of the accumulator. The block (10) further comprises a plurality of pairs of stacked fastening elements (13), each comprising a first fastening element (14) supporting a first tab (15) of the accumulator and a second fastening element (16) supporting a second tab (17) of the accumulator, wherein the pairs of fastening elements maintain pressure contact between the tabs and adjacent pairs of fastening elements and together with the tabs form an electrical connection; a layer (11) made of electrical insulating material disposed between adjacent accumulators of each pair; and removable fastening means enabling the fastening elements (13) to be removably fastened.

Description

Technical Field

[0001] The present invention relates to the field of electrochemical accumulators, and more particularly to metal ion accumulators.

[0002] More particularly, the present invention relates, in the remainder of the present application, to a stack of accumulators having a flexible packaging generally referred to as a "pouch cell" or simply a "cell".

Background Art

[0003] As shown in FIG. 1, an electrical energy accumulator 1 typically includes at least one electrochemical cell 2 comprising an electrolyte 3 interposed between a positive electrode or cathode 4 and a negative electrode or anode 5, a current collector 6 connected to the cathode 4, a current collector 7 connected to the anode 5, and finally a packaging 8 configured to house the electrochemical cell and to seal the electrochemical cell against the outside air and the electrolyte inside the cell, the packaging 8 through which a part of the current collector passes.

[0004] Depending on the type of application, the packaging can be flexible or rigid.

[0005] The main advantage of flexible packaging is that it is lightweight. Thus, accumulators with the highest energy density have flexible packaging.

[0006] FIG. 2 shows this type of flexible packaging 8 configured to insulate and seal the electrochemical cell 2, through which a part of the two conductive tabs 6, 7 passes. The conductive tabs are each arranged on opposite sides of the accumulator 1 and extend in the plane of the electrochemical cell 2, and the conductive tabs form the electrodes of the accumulator 1.

[0007] ​In most applications of the prior art, it is necessary to combine multiple cells in series and / or parallel to reach the target current and / or voltage levels.

[0008] A battery or battery pack refers to its final form as an electrical energy storage element, but it is possible to identify multiple levels of cell grouping.

[0009] Modules are subassemblies of identical cells, enabling a higher level of granularity for systems requiring a large number of basic cells. Modules are complex and expensive components that integrate numerous structural, electrical, and thermal functions.

[0010] A battery is the result of a combination of modules, each composed of a combination of cells.

[0011] For example, Chinese Patent No. 109428024(B) describes a battery module in which flexible accumulators are assembled and connected to one another using mounting elements, the mounting elements fastening tabs to which the flexible accumulators are bent and electrically connected by welding flat T-shaped conductive elements.

[0012] These "modular" type architectures use welded electrical connections that cannot be disassembled in the event of a failure. [Overview of the Initiative]

[0013] The proposed invention aims to facilitate the replacement of flexible accumulators that conform to a “cell-to-pack” architecture in which cells are directly integrated into a battery pack without “module” type intermediate grouping, as in the case of Chinese Patent No. 109428024(B). Therefore, in the remainder of this application, the phrases “cell block” or “block of cells,” or simply the term “block,” mean multiple adjacent cells, and these multiple adjacent cells should not be confused with a “module,” since these cells do not replicate all the functions of a module.

[0014] Accordingly, the present invention relates to a battery cell block, particularly for an automatic vehicle, comprising a plurality of laterally arranged flexible accumulators, each flexible accumulator comprising two tabs positioned on either side of the accumulator and forming electrodes for the accumulator.

[0015] The block also comprises a plurality of stacked mounting element pairs, each comprising a first mounting element supporting a first tab of the accumulator and a second mounting element supporting a second tab of the accumulator, the pair of mounting elements for maintaining the tab in pressure contact with an adjacent pair of mounting elements and for forming an electrical connection together with the tab.

[0016] The block also includes a layer of electrical insulating material, which is placed between each pair of adjacent accumulators, for reducing vibrations of the accumulators.

[0017] The block further comprises removable mounting means that enable the mounting elements to be assembled in a removable manner.

[0018] According to one feature, the electrical connection portion is made of a metal lug placed on the mounting element, and the two mounting elements are stacked to make pressure contact with the tab.

[0019] According to another feature, the layer comprises a foam or an adhesive.

[0020] Advantageously, each mounting element is provided with at least one boss arranged on the upper surface of the mounting element and a cavity formed in a straight line with the boss on the lower surface of the mounting element, the cavity having a shape complementary to the boss and being for accommodating the boss of an adjacent mounting element when the mounting elements are stacked.

[0021] For example, the removable mounting means includes clipping means and / or screwing means.

[0022] Advantageously, the mounting element is provided with measuring means for measuring voltage and / or temperature.

[0023] Preferably, the mounting element is provided with means for applying pressure to the metal lugs and tabs.

[0024] According to another feature, the block is provided with electrical connection means passing through the mounting element inside a sheath arranged in the mounting element.

[0025] The present invention also relates to an electric battery comprising a plurality of the above blocks, wherein the blocks are combined in series and / or in parallel.

[0026] The present invention also relates to a motor vehicle equipped with the above battery.

[0027] Other objects, features and advantages of the present invention will appear when reading the following description which is provided merely as a non-limiting example with reference to the accompanying drawings.

Brief Description of the Drawings

[0028] [Figure 1] It is a schematic perspective exploded view showing various elements of a lithium-ion accumulator. [Figure 2]Perspective view of a prismatic lithium-ion accumulator with flexible packaging according to the prior art. [Figure 3] End face cross-sectional view of a battery block according to the present invention. [Figure 4] Left side view of the battery block shown in FIG. 3. [Figure 5] Right side view of the battery block shown in FIG. 3. [Figure 6] End face view of a mounting element according to the present invention. [Figure 7] End face view of a mounting element provided with means for applying pressure according to the present invention. [Figure 8] View showing the electrical connection means according to the present invention.

Mode for Carrying Out the Invention

[0029] Detailed description of at least one embodiment Although described with respect to lithium-ion accumulators, the present invention applies to any metal-ion accumulator or, more generally, to any electrochemical accumulator.

[0030] The battery block according to the present invention can be of the on-board or stationary type. For example, the fields of electric transport and hybrid transport as well as grid-connected storage systems can be considered in the context of the present invention.

[0031] Figures 1 and 2 already discussed in the preamble relate to examples of lithium-ion accumulators and flexible packaging according to the prior art.

[0032] For clarity, the same reference numerals indicating the same elements according to the prior art and the present invention are used throughout the figures of the present application.

[0033] In the illustrated example, the accumulator 1 is in a prismatic form with flexible packaging 8, which is usually called a "pouch".

[0034] Next, an embodiment of the battery block shown in Figures 3 to 5 according to the present invention will be described.

[0035] Figure 3 is an end-face cross-sectional view of the battery block 10 according to the present invention. Figures 4 and 5 are left and right views, respectively, of the battery block 10 shown in Figure 3.

[0036] The battery block 10 comprises a plurality of juxtaposed electrical energy accumulators 1 separated from each other by a layer 11, the layer 11 being for reducing vibration of the accumulators 1. Each accumulator 1 comprises at least one electrochemical cell having an electrolyte interposed between the cathode and anode, a current collector connected to the cathode, a current collector connected to the anode, and packaging.

[0037] The purpose of layer 11 is to provide support perpendicular to the cell plane in order to improve the mechanical retention of the accumulators and to promote good distribution of compressive forces between the accumulators. Furthermore, layer 11 is equipped with an electrical insulating material to reduce leakage current caused by the potential difference of the accumulators.

[0038] For example, layer 11 may contain foam or adhesive.

[0039] Preferably, such a layer 11 is also placed between the accumulator 1 and the support surface 12 to which the block 10 is attached.

[0040] Block 10 comprises pairs of multiple stacked mounting elements 13 positioned on both sides of the accumulator 1.

[0041] While the vertical arrangement of accumulators 1 has been described, the present invention also covers the case where accumulators are arranged horizontally. In this case, the support surface 12 is vertical, and the mounting elements 13 are stacked horizontally.

[0042] Each pair of mounting elements comprises a first mounting element 14 that supports the first tab 15 of the accumulator and a second mounting element 16 that supports the second tab 17 of the accumulator.

[0043] The pair of mounting elements is for pressing the tabs 15 and 17 against an adjacent pair of mounting elements. Therefore, three pairs of mounting elements are needed to mount two cells, and one additional pair of mounting elements is needed to mount each additional cell.

[0044] The pair of mounting elements described above, together with the tabs, also constitute an electrical connection.

[0045] The electrical connection portion is made by a metal lug 18 placed on the mounting element 13, and by stacking the two mounting elements 13, it is brought into pressure contact with the tabs 15 and 17.

[0046] The accumulator can be electrically connected in series and / or parallel within the block 10 according to the present invention.

[0047] Whether the accumulators are electrically assembled in series and / or parallel depends on the orientation of the accumulators and the arrangement of the metal lugs 18.

[0048] It should be understood that the arrangement of the metal lugs 18 may differ from the arrangement shown in Figures 3 to 5, depending on the intended assembly.

[0049] The battery block 10 is provided with an electrical connection means 21 that passes through the mounting element inside a sheath 22 located within the mounting element. The electrical connection means 21 connects one electrode from the end close to the support surface 12 upwards through the stack to the opposite end (Figure 8). The electrical connection means 21 is different from the metal lug 18.

[0050] The mounting element 13 is provided with removable mounting means that enable the elements 13 to be assembled in a way that allows them to be detachably assembled from one another.

[0051] The removable mounting means includes clipping means and / or screw fastening means 19, 20.

[0052] In the embodiments shown in Figures 3 to 5, the elements 13 are assembled by tightening screws 19 and 20, which are inserted through a stack of mounting elements 13 and locked into the support surface 12. Preferably, there is a pair of screws for each stack of mounting elements 13.

[0053] Boss 23 is connected to cavity 25 by a threaded cylindrical channel 27, which is for interacting with screws 19 and 20 (Figure 6).

[0054] Figure 6 is an end view of a mounting element 13. The mounting element 13 includes at least one boss 23 located on the upper surface 24 of the mounting element. The mounting element 13 includes a cavity 25 formed in line with the boss 23 on the lower surface 26 of the mounting element. The cavity 25 has a shape complementary to the boss 23 and is intended to accommodate the boss 23 of adjacent mounting elements 13 when the mounting elements are stacked. The presence of the boss 23 and the associated cavity 25 tends to facilitate the relative positioning of the mounting elements 13.

[0055] In another embodiment not shown, the mounting element 13 is assembled by a boss 23 and clipping means positioned on the cavity 25. For example, the boss 23 is provided with an elastic snap hook facing outward, which snaps into a snap opening provided on the outer edge of the cavity 25 when the elements 13 are stacked. When disassembled, the snap hook is pushed inward from the snap opening.

[0056] It is certainly possible to combine screw fastening means and clipping means to assemble the mounting element 13.

[0057] Figure 7 is an end view of a mounting element 13, which has a first cavity 28 located on the upper surface 24 of the mounting element and a second cavity 29 located on the lower surface 26 of the mounting element.

[0058] The cavities 28 and 29 house means for applying pressure 30 to the metal lugs 18 together with the tabs 15 and 17. The means for applying pressure 30 includes a spring, which tends to push the ends of the metal lugs 18 outward, with the aim of increasing the contact pressure with the tabs 15 and 17. Depending on the desired configuration, it is possible to provide means for applying pressure 30 in only one of the cavities 28 or 29.

[0059] The mounting element 13 is further provided with measuring means 31 for measuring voltage and / or temperature. The measuring means 31 includes an electrical connection 32, which connects a metal lug 18 to a measuring terminal 33 located on the side of the mounting element 13.

[0060] Means for applying pressure 30 can be used to increase the contact pressure between the electrical connection means 21 and the tabs 15 and 17 (Figure 8).

[0061] To mitigate electrical interference, block 10 may further comprise a cover made of an electrically insulating material, positioned on the metal lugs of the mounting element to prevent accidental contact between the metal lugs and the outside.

[0062] Depending on the desired configuration, multiple battery blocks 10 may be combined in series and / or parallel within the electric battery. The present invention aims to improve the mass energy density of such a battery because the accumulator 1 is placed directly within the battery without using a “module” type mechanical protection structure for the battery blocks 10.

Claims

1. In particular, a battery cell block (10) for an autonomous vehicle, The device comprises a plurality of flexible accumulators (1) arranged side by side, each flexible accumulator (1) having two tabs (6, 7) positioned on both sides of the accumulator and forming electrodes of the accumulator, The aforementioned block (10) is A pair of multiple stacked mounting elements (13), each comprising a first mounting element (14) supporting a first tab (15) of the accumulator and a second mounting element (16) supporting a second tab (17) of the accumulator, wherein the pair of mounting elements maintains a state in which the tabs are in pressure contact with adjacent pairs of mounting elements and forms an electrical connection together with the tabs, To reduce vibrations of the accumulators, a layer (11) made of an electrically insulating material is placed between each pair of adjacent accumulators (13), Removable mounting means that enable the mounting element (13) to be assembled in a removable manner. A block (10) further characterized by having the following features.

2. The block according to claim 1, wherein the electrical connection portion is made of a metal lug (18) placed on the mounting element (13), and the two mounting elements (13) are stacked to make them in pressure contact with the tabs (15, 17).

3. The block according to claim 1 or 2, wherein the layer (11) comprises a foam or an adhesive.

4. The block according to any one of claims 1 to 3, wherein each mounting element (13) is provided with at least one boss (23) located on the upper surface (24) of the mounting element and a cavity (25) formed in a straight line with the boss on the lower surface (26) of the mounting element, the cavity having a shape complementary to the boss and for accommodating the boss (23) of adjacent mounting elements when the mounting elements are stacked.

5. The block according to any one of claims 1 to 4, wherein the removable mounting means includes clipping means and / or screw fastening means (19, 20).

6. The block according to any one of claims 1 to 5, wherein the mounting element (13) is provided with measuring means (31) for measuring voltage and / or temperature.

7. The block according to any one of claims 1 to 6, wherein the mounting element is provided with means for applying pressure (30) to the metal lug (18) and the tabs (15, 17).

8. The block according to any one of claims 1 to 7, wherein an electrical connection means (21) passing through the mounting element (13) is provided inside a sheath (22) disposed within the mounting element.

9. An electric battery comprising a plurality of blocks (10) according to any one of claims 1 to 8, wherein the blocks are arranged in series and / or parallel.

10. An automatic vehicle equipped with the battery described in claim 9.

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