Battery cells and batteries

Abstract

This application provides a battery cell and a battery, relating to the field of battery technology. The battery cell includes a casing, an electrode assembly module, a first adapter, and a second adapter. The electrode assembly module is housed in a receiving cavity and includes multiple electrode assemblies connected in series. The electrode assembly module has a first tab and a second tab on one side along a first direction, and a third tab and a fourth tab on the other side along the first direction. The first tab and the second tab have opposite polarities, the third tab and the fourth tab have opposite polarities, and the first tab and the third tab have the same polarity. The first adapter connects the first tab, the third tab, and a first electrode terminal. The second adapter connects the second tab, the fourth tab, and the second electrode terminal. The battery cell of this application can significantly reduce internal impedance, improve the temperature rise during the internal charging and discharging process, reduce internal energy loss, and improve energy efficiency.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cell and a battery. Background Technology

[0002] With the increasing popularity of new energy vehicles, the performance requirements for power batteries in these vehicles are also becoming more stringent. In related technologies, each battery cell typically uses multiple electrode assemblies connected in parallel to increase its capacity. This parallel connection requires welding the positive and negative terminals to the positive and negative tabs, resulting in a stacked arrangement of the electrode assemblies. This significantly increases the thickness of the battery cell, leading to a large temperature difference between the core and outer layers during charging and discharging. Over time, this results in significant performance differences across different parts of the battery cell, causing rapid performance degradation. Utility Model Content

[0003] The purpose of this application is to provide a battery cell and a battery to solve the technical problem in the prior art where large temperature differences at different locations inside the battery cell lead to rapid performance degradation.

[0004] In a first aspect, this application provides a battery cell, comprising: a casing, an electrode assembly module, a first adapter, and a second adapter. The casing has a receiving cavity, and a first electrode terminal and a second electrode terminal are respectively provided on opposite sides of the casing along a second direction. The electrode assembly module is housed in the receiving cavity and includes multiple electrode assemblies connected in series. The electrode assembly module has a first tab and a second tab on one side along the first direction, and a third tab and a fourth tab on the other side along the first direction. The polarities of the first tab and the second tab are opposite, the polarities of the third tab and the fourth tab are opposite, and the polarities of the first tab and the third tab are the same. The first adapter connects the first tab, the third tab, and the first electrode terminal. The second adapter connects the second tab, the fourth tab, and the second electrode terminal, wherein the first direction and the second direction are perpendicular to each other.

[0005] In one or more embodiments of this application, a plurality of electrode assemblies are arranged sequentially along a second direction. Each electrode assembly includes a battery cell body. A first electrode tab and a second electrode tab protrude from one side of the battery cell body in the first direction, and a third electrode tab and a fourth electrode tab protrude from the other side of the battery cell body in the first direction. In two adjacent electrode assemblies, the second electrode tab of one electrode assembly and the first electrode tab of another electrode assembly are arranged adjacently and electrically connected through a first connecting piece, and the fourth electrode tab of one electrode assembly and the third electrode tab of another electrode assembly are arranged adjacently and electrically connected through a second connecting piece.

[0006] Among all the electrode assemblies, the first electrode tab closest to the first electrode terminal is the first electrode tab, the third electrode tab closest to the first electrode terminal is the third electrode tab, the second electrode tab closest to the second electrode terminal is the second electrode tab, and the fourth electrode tab closest to the second electrode terminal is the fourth electrode tab.

[0007] In one or more embodiments of this application, a bracket is further included. The bracket includes a first side plate and a second side plate disposed opposite to each other along a first direction. The first side plate faces the side of the electrode assembly module and has a first positioning protrusion corresponding to each cell body. The first positioning protrusion abuts against the cell body; and / or,

[0008] The second side plate faces the side of the electrode assembly module and has a second positioning protrusion corresponding to each cell body, with the second positioning protrusion abutting against the cell body.

[0009] In one or more embodiments of this application, the first side plate and the second side plate are both recessed inward along the third direction to form a first receiving groove. The first electrode lug, the second electrode lug, the third electrode lug, and the fourth electrode lug all include a connecting portion. The first receiving groove on the first side plate is used to receive the first connecting piece and the connecting portion connected to the first connecting piece. The first receiving groove on the second side plate is used to receive the second connecting piece and the connecting portion connected to the second connecting piece.

[0010] In one or more embodiments of this application, the first adapter component includes a first adapter piece and a second adapter piece, both of which include a first connecting portion and a second connecting portion. The first connecting portion of the first adapter piece is connected to a first electrode tab, and the first connecting portion of the second adapter piece is connected to a third electrode tab. The second connecting portions of both the first and second adapter pieces are connected to a first electrode terminal; and / or,

[0011] The second adapter component includes a third adapter piece and a fourth adapter piece. Both the third adapter piece and the fourth adapter piece include a third connecting portion and a fourth connecting portion. The third connecting portion of the third adapter piece is connected to the second electrode tab, and the third connecting portion of the fourth adapter piece is connected to the fourth electrode tab. Both the fourth connecting portions of the third adapter piece and the fourth connecting portion of the fourth adapter piece are connected to the second electrode terminal.

[0012] In one or more embodiments of this application, one of the second connecting portions of the first adapter piece and the second connecting portion of the second adapter piece is provided with a latching protrusion, and the other is provided with a latching groove. The second connecting portions of the first adapter piece and the second connecting portions of the second adapter piece are locked together by the engagement of the latching protrusion and the latching groove; and / or,

[0013] The fourth connecting part of the third adapter piece and the fourth connecting part of the fourth adapter piece are provided with a locking protrusion and a locking groove, respectively. The fourth connecting part of the third adapter piece and the fourth connecting part of the fourth adapter piece are locked and fixed by the cooperation of the locking protrusion and the locking groove.

[0014] In one or more embodiments of this application, the bracket further includes a third side plate and a fourth side plate disposed opposite to each other along a second direction, and the first side plate, the third side plate, the second side plate and the fourth side plate are connected to form a frame structure.

[0015] The first side plate is recessed inward along one side in the third direction to form a second receiving groove, and the second receiving groove at one end of the first side plate along the second direction is used to accommodate the connecting part of the first electrode tab and the first connecting part of the first adapter piece; the second receiving groove at the other end of the first side plate along the second direction is used to accommodate the connecting part of the second electrode tab and the third connecting part of the third adapter piece; and / or,

[0016] The second side plate is recessed inward along one side of the third direction to form a third receiving groove, and the third receiving groove located at one end of the second side plate along the second direction is used to accommodate the connecting part of the third electrode and the first connecting part of the second adapter piece; the third receiving groove located at the other end of the second side plate along the second direction is used to accommodate the connecting part of the fourth electrode and the third connecting part of the fourth adapter piece.

[0017] In one or more embodiments of this application, it further includes: an insulating film, wherein the first electrode lug, the second electrode lug, the third electrode lug, and the fourth electrode lug all include a bent portion, the connecting portion has a connecting end connected to the bent portion and a free end disposed away from the connecting end, and the insulating film at least covers the free end.

[0018] In one or more embodiments of this application, the bracket is provided with weight-reducing holes.

[0019] Secondly, this application provides a battery comprising the battery cell described in any one of the first aspects.

[0020] Based on the above technical solution, the battery cell and battery of this application have at least the following beneficial technical effects:

[0021] The battery cell of this application forms an electrode assembly module by connecting multiple electrode components in series. The electrode assembly module has a first tab and a second tab on one side along the first direction, i.e., its width direction, and a third tab and a fourth tab on the other side. The first tab and the third tab have the same polarity and are connected to the first electrode terminal of the housing through a first adapter. The second tab and the fourth tab have the same polarity and are connected to the second electrode terminal of the housing through a second adapter. This forms a battery cell with tabs extending from both sides in the first direction and multiple electrode components connected in series. This can significantly reduce the internal impedance of the battery cell, improve the temperature rise during the internal charging and discharging process, reduce the internal energy loss of the battery, improve energy efficiency, and improve the safety of the battery. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a battery cell provided in an embodiment of this application.

[0024] Figure 2 This is a schematic diagram of the electrode assembly in a battery cell provided in an embodiment of this application.

[0025] Figure 3 This is a side view of the electrode assembly in a battery cell provided in an embodiment of this application.

[0026] Figure 4 This is a schematic diagram of the electrode assembly module in a battery cell provided in an embodiment of this application.

[0027] Figure 5 This is a schematic diagram of the connection method between the connecting part of the electrode assembly and the connecting piece in the battery cell provided in this application embodiment.

[0028] Figure 6 This is a schematic diagram of the structure of the first or second adapter component in the battery cell provided in the embodiments of this application.

[0029] Figure 7 This is a schematic diagram of the structure of the first or second adapter component in a battery cell provided in another embodiment of this application.

[0030] Figure 8This is a schematic diagram showing the connection between the first electrode terminal and the first adapter or the second electrode terminal and the second adapter in a battery cell provided in the embodiments of this application.

[0031] Figure 9 This is a schematic diagram of the structure of the support in the battery cell provided in the embodiments of this application.

[0032] Figure 10 This is a schematic diagram of the structure of the support in a battery cell provided in another embodiment of this application.

[0033] Figure 11 This is a schematic diagram of the structure of the support and electrode assembly module in the battery cell provided in the embodiments of this application.

[0034] Figure 12 This is a partial cross-sectional view of the connection between the support and the electrode assembly module in the battery cell provided in the embodiments of this application.

[0035] Figure 13 This is a partial cross-sectional view of the connection between the support and the electrode assembly in a battery cell provided in another embodiment of this application.

[0036] Figure 14 This is a partial structural diagram of the support structure in a battery cell provided in an embodiment of this application.

[0037] In the diagram; 10 - Electrode assembly module; 11 - First electrode tab; 11' - Third electrode tab; 12 - Second electrode tab; 12' - Fourth electrode tab; 13 - First adapter component; 14 - Second adapter component; 15 - First connecting piece; 15' - Second connecting piece; 16 - Solder joint; 20 - Housing; 21 - First electrode terminal; 22 - Second electrode terminal; 30 - Bracket; 31 - First side plate; 31' - Second side plate; 32 - Third side plate; 32' - Fourth side plate; 33 - First positioning protrusion; 33' - Second positioning protrusion; 34 - First receiving groove; 35 - Fourth receiving groove; 36 - Fifth receiving groove; 37 - Second receiving groove; 37' - Third receiving groove 38 - Notch; 39 - Weight reduction hole; 100 - Electrode assembly; 101 - Cell body; 110 - Connecting part; 111 - First electrode tab; 112 - Third electrode tab; 113 - Insulating film; 114 - Bending part; 121 - Second electrode tab; 122 - Fourth electrode tab; 151 - First solder mark; 131 - First adapter piece; 132 - Second adapter piece; 133 - Locking protrusion; 134 - Locking groove; 141 - Third adapter piece; 142 - Fourth adapter piece; 1101 - Connecting end; 1102 - Free end; 1311 - First connecting part; 1312 - Second connecting part; 1411 - Third connecting part; 1412 - Fourth connecting part. Detailed Implementation

[0038] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0039] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0040] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0042] In related technologies, battery cells are typically constructed by connecting one or more electrode assemblies in parallel to increase the capacity of a single cell. However, connecting electrode assemblies in parallel requires welding the positive and negative terminals to the positive and negative tabs respectively, and the electrode assemblies need to be stacked. This configuration results in a significant increase in the thickness of the battery cell, leading to a large temperature difference between the center and outer layers during charging and discharging. Over time, this can cause significant performance differences at different locations within the electrode assembly, resulting in rapid performance degradation of the battery cell.

[0043] Based on the above considerations, and in order to solve the technical problem of rapid performance degradation caused by large temperature differences at different locations within a single battery cell in the prior art, this application provides a battery and a single battery cell.

[0044] The battery described in this application can be applied to electrical devices that use batteries as operating or driving power sources. These devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, power tools, energy storage devices, amusement equipment, elevators, and lifting equipment, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, or electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.; energy storage devices can be energy storage walls, base station energy storage, container energy storage, etc.; amusement equipment can be carousels, drop towers, etc.

[0045] This application describes an electrical device using a vehicle as an example. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery is installed inside the vehicle, and the battery can be located at the bottom, front, or rear of the vehicle. The battery can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller controls the battery to supply power to the motor, for example, to meet the power needs of starting, navigation, and driving the vehicle. The battery can not only serve as the vehicle's operating power source but also as its driving power source, replacing or partially replacing gasoline or natural gas to provide driving power to the vehicle.

[0046] As one embodiment of the battery, the aforementioned battery can be a battery pack or a battery module. When the battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and multiple battery cells. The multiple battery cells can be electrically connected in series, parallel, or a combination of series and parallel connections, and communicate with the battery management system, which controls and monitors the operating status of each battery cell. Alternatively, multiple battery cells can first be combined with a module management system to form a battery module, and then the multiple battery modules can be electrically connected in series, parallel, or a combination of series and parallel connections to form a battery pack together with the battery management system.

[0047] It should be noted that the first direction, the second direction, and the third direction in this application are mutually perpendicular. The first direction can be the width direction of the battery cell, the second direction can be the length direction of the battery cell, and the third direction can be the height direction or the thickness direction of the battery cell.

[0048] As one embodiment of a battery cell, please refer to Figure 1A battery cell refers to the smallest unit that makes up a battery. A battery cell includes: a casing 20, an electrode assembly module 10, a first adapter 13, and a second adapter 14. The casing 20 has a receiving cavity. The casing 20 is used to house the electrode assembly module 10 and other components, and the shape of the casing 20 can be determined according to the specific shape and size of the electrode assembly module 10. The casing 20 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0049] In some embodiments, the housing 20 includes a top cover assembly and a housing. The housing has an opening at at least one end along a second direction, and the top cover assembly covers the opening of the housing to isolate the internal environment of the battery cell from the external environment. The housing has a receiving cavity inside to accommodate the electrode assembly module 10 within the receiving cavity of the housing. The housing is a component used to cooperate with the top cover assembly to form the internal environment of the battery cell, wherein the formed internal environment can be used to accommodate the electrode assembly module 10 and other components. The housing and the top cover assembly can be independent components, and an opening can be provided on the housing. The internal environment of the battery cell is formed by the top cover assembly covering the opening. The housing can be of various shapes and sizes, such as cylindrical, cuboid, hexagonal prism, etc. Specifically, the shape of the housing can be determined according to the specific shape and size of the electrode assembly module 10. For example, in the embodiments of this application, the shape of the housing can be cuboid. The material of the housing can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of this application do not impose special limitations on this.

[0050] The outer casing 20 has a first electrode terminal 21 and a second electrode terminal 22 respectively on opposite sides along the second direction. It is understood that the first electrode terminal 21 and the second electrode terminal 22 can be located on the top cover assembly. The first electrode terminal 21 and the second electrode terminal 22 have opposite polarities. The first electrode terminal 21 and the second electrode terminal 22 are electrical connectors, with one end connected to a tab and the other end connected to an external electrical connector, used to draw current out of or into the electrode assembly module 10.

[0051] The electrode assembly module 10 is housed in the receiving cavity of the housing 20. The electrode assembly module 10 includes multiple electrode assemblies 100, which are mainly formed by winding or stacking positive and negative electrode sheets. This application describes the electrode assembly 100 as a stacked structure. Typically, a separator is provided between the positive and negative electrode sheets. During the charging and discharging process of a single battery cell, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrode sheets. The separator, placed between the positive and negative electrode sheets, can reduce short circuits between the positive and negative electrodes while allowing active ions to pass through. This application does not impose any particular limitation on the type of separator; any known porous separator with good chemical and mechanical stability can be selected. The positive electrode sheet may include a positive current collector and positive active material layers coated on opposite sides of the positive current collector. The negative electrode sheet may include a negative current collector and negative active material layers coated on opposite sides of the negative current collector. The portions of the positive and negative electrode plates containing active material constitute the main body 101 of the electrode assembly 100, while the portions of the positive and negative electrode plates without active material each constitute the tab.

[0052] In this application, multiple electrode assemblies 100 are connected in series, that is, the positive electrode tab of one of two adjacent electrode assemblies 100 is connected to the negative electrode tab of the other electrode assembly 100. Compared with the electrode assemblies 100 connected in series in the prior art, the battery cell of this application has the advantages of high voltage and low current during manufacturing, formation and capacity testing stages, which can reduce energy loss and improve the energy efficiency of the battery cell.

[0053] The electrode assembly module 10 has a first tab 11 and a second tab 12 on one side along the first direction, and a third tab 11' and a fourth tab 12' on the other side along the first direction; wherein the polarity of the first tab 11 is opposite to that of the second tab 12, the polarity of the third tab 11' is opposite to that of the fourth tab 12', and the polarity of the first tab 11 and the third tab 11' is the same. For example, if the first tab 11 and the third tab 11' are positive, then the second tab 12 and the fourth tab 12' are negative. Of course, the polarity of the first electrode 11 and the third electrode 11' can also be negative, then the polarity of the second electrode 12 and the fourth electrode 12' will be positive. It is only necessary to ensure that the polarity of the first electrode 11 and the third electrode 11' is the same, the polarity of the second electrode 12 and the fourth electrode 12' is the same, and the polarities of the first electrode 11 and the second electrode 12 are opposite, and the polarities of the third electrode 11' and the fourth electrode 12' are opposite.

[0054] It is understood that in the electrode assembly module 10 of this application, the first tab 11 and the third tab 11' are located at the same end of the electrode assembly module 10 along the second direction, and the second tab 12 and the fourth tab 12' are located at the other end of the electrode assembly module 10 along the second direction. This results in one set of tabs with the same polarity at one end of the battery cell in the second direction, and another set of tabs with the same polarity at the other end of the second direction. The first adapter 13 connects the first tab 11, the third tab 11', and the first electrode terminal 21; the second adapter 14 connects the second tab 12, the fourth tab 12', and the second electrode terminal 22. It is understood that the first adapter 13 and the second adapter 14 can be adapter pieces to achieve electrical connection between the first tab 11, the third tab 11', and the first electrode terminal 21, or to achieve electrical connection between the second tab 12, the fourth tab 12', and the second electrode terminal 22.

[0055] In the technical solution of this application embodiment, tabs extend from both sides in the first direction. Compared with the battery cell with tabs on only one side in the prior art, the internal impedance of the battery cell can be greatly reduced, the temperature rise during the internal charging and discharging process of the battery can be improved, the internal energy loss of the battery can be reduced, the energy efficiency can be improved, and the safety of the battery can be improved.

[0056] Please refer to Figure 1 In some embodiments, multiple electrode assemblies 100 are arranged sequentially along a second direction. It is understood that the multiple electrode assemblies 100 are laid out flat along the second direction and connected in series. This forms a battery cell in which multiple electrode assemblies 100 are laid out flat along the length of the battery cell, resulting in uniform heat distribution during charging and discharging, improving the problem of uneven heat distribution in stacked battery cells, and increasing the energy efficiency of the battery cell. Of course, the multiple electrode assemblies 100 can also be arranged sequentially along a third direction.

[0057] In some embodiments, please refer to Figure 2 and Figure 3 As shown, the electrode assembly 100 includes a battery cell body 101. A first electrode tab 111 and a second electrode tab 121 protrude from one side of the battery cell body 101 in a first direction, and a third electrode tab 112 and a fourth electrode tab 122 protrude from the other side of the battery cell body 101 in the same first direction. The first electrode tab 111 and the third electrode tab 112 have the same polarity, the second electrode tab 121 and the fourth electrode tab 122 have the same polarity, and the first electrode tab 111 and the second electrode tab 121 have opposite polarities. It should be noted that multiple first electrode tabs 111, second electrode tab 121, third electrode tab 112, and fourth electrode tab 122 may be included, and these multiple electrode tabs are spaced apart along a third direction, such as... Figure 3 As shown.

[0058] Please combine Figure 2 , Figure 4 As shown, in order to achieve a series connection between two adjacent electrode assemblies 100, in two adjacent electrode assemblies 100, the second electrode tab 121 of one electrode assembly 100 and the first electrode tab 111 of the other electrode assembly 100 are arranged adjacently and electrically connected through a first connecting piece 15, wherein, as Figure 5 The first connecting piece 15 is welded to the second electrode tab 121 and the first electrode tab 111 respectively to form a first solder mark 151. The fourth electrode tab 122 of one electrode assembly 100 and the third electrode tab 112 of another electrode assembly 100 are arranged adjacently and electrically connected by the second connecting piece 15'. The second connecting piece 15' is welded to either the third electrode tab 112 or the fourth electrode tab 122 to form the first solder mark 151. The first connecting piece 15 and the second connecting piece 15' can be metal connecting pieces, used to achieve series electrical connection of the positive and negative electrodes in adjacent electrode assemblies 100.

[0059] Please refer to Figure 4 All electrode assemblies 100 are arranged sequentially along the second direction. The first tab 111 closest to the first electrode terminal 21 is designated as the first tab 11; the third tab 112 closest to the first electrode terminal 21 is designated as the third tab 11'; the second tab 121 closest to the second electrode terminal 22 is designated as the second tab 12; and the fourth tab 122 closest to the second electrode terminal 22 is designated as the fourth tab 12'. It can be understood that the first tab 111 and the third tab 112 of the outermost electrode assembly 100 are designated as the first tab 11 and the third tab 11', respectively, while the second tab 121 and the fourth tab 122 of the electrode assembly 100 on the other side are designated as the second tab 12 and the fourth tab 12', respectively. This allows the current from the multiple series-connected electrode assemblies 100 to be drawn out or drawn in separately.

[0060] It should be noted that since the electrode assembly module 10 is composed of multiple electrode assemblies 100 connected in series, and the battery cell has the characteristics of high voltage and low current, the current-carrying structural components such as the first connecting piece 15, the second connecting piece 15', the first adapter 13, the second adapter 14, the first electrode terminal 21, and the second electrode terminal 22 can reduce their current-carrying cross-sectional area, thereby reducing the weight of the battery cell and lowering the cost.

[0061] In some embodiments, to further enable the first adapter 13 to connect the first electrode 11 and the third electrode 11' respectively, such as... Figure 6 or Figure 7As shown, the first adapter component 13 includes a first adapter piece 131 and a second adapter piece 132, both of which include a first connecting portion 1311 and a second connecting portion 1312. The first connecting portion 1311 of the first adapter piece 131 is connected to the first electrode tab 11, for example, by welding. The first connecting portion 1311 of the second adapter piece 132 is connected to the third electrode tab 11', for example, by welding. The second connecting portions 1312 of both the first and second adapter pieces 131 are connected to the first electrode terminal 21, for example, by laser welding. This achieves electrical connection between the first electrode tab 11 and the third electrode tab 11' of the same polarity and the first electrode terminal 21 via the first adapter component 13. In some embodiments, such as... Figure 8 As shown, the first electrode terminal 21 can be laser-welded to form a solder joint 16 with the second connection portion 1312 of the first adapter piece 131 and the second connection portion 1312 of the second adapter piece 132.

[0062] In some embodiments, such as Figure 6 or Figure 7 In the illustrated embodiment, one of the second connecting portions 1312 of the first adapter piece 131 and the second connecting portions 1312 of the second adapter piece 132 is provided with a latching protrusion 133, and the other is provided with a latching groove 134. The second connecting portions 1312 of the first adapter piece 131 and the second connecting portions 1312 of the second adapter piece 132 are locked together by the engagement of the latching protrusion 133 and the latching groove 134. For example, the latching protrusion 133 can be trapezoidal or arc-shaped, and the latching groove 134 can be trapezoidal or arc-shaped. Thus, before the first adapter component 13 is welded to the first electrode terminal 21, the latching protrusion 133 and the latching groove 134 of the second connecting portion 1312 are press-fitted and fixed, and then welded to the first electrode terminal 21. This prevents the first adapter component 13 from bending and shaking before welding to the first electrode terminal 21, thereby affecting the welding effect.

[0063] Similarly, such as Figure 11As shown, to enable the second adapter component 14 to connect the second electrode 12 and the fourth electrode 12' respectively, the second adapter component 14 includes a third adapter piece 141 and a fourth adapter piece 142. Both the third adapter piece 141 and the fourth adapter piece 142 include a third connecting portion 1411 and a fourth connecting portion 1412. The third connecting portion 1411 of the third adapter piece 141 is connected to the second electrode 12, for example, by welding. The third connecting portion 1411 of the fourth adapter piece 142 is connected to the fourth electrode 12', for example, by welding. The fourth connecting portions 1412 of both the third adapter piece 141 and the fourth adapter piece 142 are connected to the second electrode terminal 22, for example, by laser welding. This achieves electrical connection between the second electrode 12 and the fourth electrode 12' of the same polarity through the second adapter component 14 and the second electrode terminal 22. In some trials, the second electrode terminal 22 can also be laser-welded to form a solder joint 16 with the fourth connection portion 1412 of the third adapter piece 141 and the fourth connection portion 1412 of the fourth adapter piece 142.

[0064] It should be noted that the second adapter component 14 can have the same structure as the first adapter component 13. Therefore, as Figure 6 or Figure 7 In the illustrated embodiment, one of the fourth connecting portions 1412 of the third adapter piece 141 and the fourth connecting portions 1412 of the fourth adapter piece 142 is provided with a latching protrusion 133, and the other is provided with a latching groove 134. The fourth connecting portions 1412 of the third adapter piece 141 and the fourth connecting portions 1412 of the fourth adapter piece 142 are clamped and fixed by the cooperation of the latching protrusion 133 and the latching groove 134. For example, the latching protrusion 133 can be trapezoidal or arc-shaped, and the latching groove 134 can be trapezoidal or arc-shaped. Thus, before the second adapter component 14 is welded to the second electrode terminal 22, the latching protrusion 133 and the latching groove 134 of the fourth connecting portion 1412 are press-fitted and fixed, and then welded to the second electrode terminal 22 to prevent the second adapter component 14 from bending and shaking before welding to the second electrode terminal 22, thereby affecting the welding effect.

[0065] It should be noted that, in order to ensure that the electrode assembly module 10 and the housing 20 are insulated, an insulating film can be wrapped around the outside of the electrode assembly module 10 before the electrode assembly module 10 is placed inside the housing 20.

[0066] To prevent the electrode assembly module 10 from moving within the housing 20, and to ensure insulation between the electrode assembly module 10, the first adapter 13, the second adapter 14, the first connecting piece 15, and the second connecting piece 15' and the housing 20, the battery cell of this application may further include a bracket 30. The bracket 30 is used to support the electrode assembly module 10 and also to provide insulation. The material of the bracket 30 may be a polyester polymer, polyphenylene sulfide (PPS), polypropylene (PP), or polyethylene (PE), or other materials resistant to high and low temperatures and chemical corrosion.

[0067] Specifically, such as Figure 9 As shown, in some embodiments, the bracket 30 includes a first side plate 31, a second side plate 31', and a third side plate 32 and a fourth side plate 32', which are arranged opposite each other along a first direction and a second direction, respectively. The first side plate 31, the third side plate 32, the second side plate 31', and the fourth side plate 32' are connected to form a frame structure, which facilitates the installation of the electrode assembly module 10 and enables the fixing of the electrode assembly module 10. At the same time, the frame structure can reduce the weight of the bracket 30, thereby reducing the weight of the entire battery cell. By setting the bracket 30, the battery cell of this application can achieve mass production of multiple electrode assemblies 100 during the manufacturing process, improve assembly efficiency and the overall strength of the battery cell, and also facilitate the transfer and housing of the electrode assembly module 10.

[0068] To prevent the electrode assembly module 10 from shifting within the housing 20 when the battery is subjected to vibration, a first positioning protrusion 33 is provided on the side of the first side plate 31 facing the electrode assembly module 10 and corresponding to each cell body 101. The first positioning protrusion 33 abuts against the cell body 101. The first positioning protrusion 33 is used to abut against the cell body 101 to limit the electrode assembly 100. A second positioning protrusion 33' is provided on the side of the second side plate 31' facing the electrode assembly module 10 and corresponding to each cell body 101. The second positioning protrusion 33' abuts against the cell body 101, thereby limiting the electrode assembly module 10 on both sides in the first direction. It can be understood that the first positioning protrusion 33 can be formed by protruding from the first side plate 31 towards the electrode assembly module 10, and the second positioning protrusion 33' can be formed by protruding from the second side plate 31' towards the electrode assembly module 10. The first positioning protrusion 33 and the second positioning protrusion 33' can be arranged opposite each other in the second direction or staggered. In some embodiments, the length of the first positioning protrusion 33 allows it to be positioned between the first electrode tab 111 and the second electrode tab 121 along the second direction of each electrode assembly 100. In some embodiments, the length of the first positioning protrusion 33 is 2 to 5 mm smaller than the distance between the first electrode tab 111 and the second electrode tab 121. Specifically, the length of the first positioning protrusion 33 is 2 mm, 3 mm, 4 mm, or 5 mm smaller than the distance between the first electrode tab 111 and the second electrode tab 121. The length of the second positioning protrusion 33' allows it to be positioned between the third electrode tab 112 and the fourth electrode tab 122 along the second direction of each electrode assembly 100. The length of the second positioning protrusion 33' is 2 to 5 mm smaller than the distance between the second electrode tab 121 and the fourth electrode tab 122. Specifically, the length of the second positioning protrusion 33' is 2 mm, 3 mm, 4 mm, or 5 mm smaller than the distance between the second electrode tab 121 and the fourth electrode tab 122.

[0069] In some embodiments, in a third direction, the thickness of the first side plate 31 and the second side plate 31' of the bracket 30 is not greater than the thickness of the electrode assembly 100. This allows the bracket 30 and the electrode assembly module 10 to be housed together within the housing 20. In a second direction, the length of the first side plate 31 and the second side plate 31' of the bracket 30 is determined by design and may be no greater than or greater than the length of the electrode assembly module 10.

[0070] To achieve isolation and insulation of the bracket 30, such as Figure 9 or Figure 10As shown, the first side plate 31 and the second side plate 31' are both recessed inward along the third direction to form a first receiving groove 34. The opening of the first receiving groove 34 can face the third direction, or it can be open on both sides of the first side plate 31 or the second side plate 31' in the third direction.

[0071] like Figure 5 As shown, the first electrode lug 111, the second electrode lug 121, the third electrode lug 112, and the fourth electrode lug 122 all include a connecting portion 110. The connecting portion 110 is used to weld to the first connecting piece 15 or the second connecting piece 15', forming a first solder mark 151. The first receiving groove 34 located on the first side plate 31 is used to receive the first connecting piece 15 and the connecting portion 110 connected to the first connecting piece 15, as shown. Figure 11 and Figure 12 As shown, it can be understood that the first connecting piece 15 and the connecting portion 110 connected to the first connecting piece 15 can be placed in the groove of the first receiving groove 34. The first receiving groove 34 located on the second side plate 31' is used to receive the second connecting piece 15' and the connecting portion 110 connected to the second connecting piece 15', that is, the first receiving groove 34 located on the second side plate 31' is used to receive the second connecting piece 15' and the connecting portion 110 connected to the second connecting piece 15'. In this way, the groove wall of the first receiving groove 34 can isolate the first connecting piece 15, the second connecting piece 15' and the electrode assembly module 10, which can prevent the electrode tab from being inserted into the electrode assembly 100 and causing a short circuit, thus playing an insulating role.

[0072] It should be noted that multiple first receiving slots 34 can be provided on the first side plate 31, and each slot corresponds one-to-one with the first connecting piece 15; multiple first receiving slots 34 can be provided on the second side plate 31', and each slot corresponds one-to-one with the second connecting piece 15'. Of course, only one first receiving slot 34 can be provided on the first side plate 31, which can accommodate all the first connecting pieces 15; only one first receiving slot 34 can be provided on the second side plate 31', which can accommodate all the second connecting pieces 15'.

[0073] In some embodiments, such as Figure 12 As shown, the groove depth H of the first receiving groove 34 is greater than the width of the first connecting piece 15 or the second connecting piece 15', and the groove width L of the first receiving groove 34 is greater than the sum of the thickness of the first connecting piece 15 or the second connecting piece 15' and the total thickness of the connecting portion 110, so that the first receiving groove 34 located on the first side plate 31 can completely accommodate the first connecting piece 15, and the first receiving groove 34 located on the second side plate 31' can completely accommodate the second connecting piece 15'.

[0074] In some embodiments, such as Figure 9 or Figure 10 As shown, the first side plate 31 is recessed inward along one side of the third direction to form a second receiving groove 37. Since the first connecting portion 1311 of the first adapter piece 131 is welded to the first electrode 11, the second receiving groove 37 located at one end of the first side plate 31 along the second direction is used to accommodate the connecting portion 110 of the first electrode 11 and the first connecting portion 1311 of the first adapter piece 131. Since the third connecting portion 1411 of the third adapter piece 141 is welded to the second electrode 12, the second receiving groove 37 located at the other end of the first side plate 31 along the second direction is used to accommodate the connecting portion 110 of the second electrode 12 and the third connecting portion 1411 of the third adapter piece 141, thereby achieving insulation.

[0075] The second side plate 31' is recessed inward along one side in the third direction to form a third receiving groove 37'. Since the first connecting portion 1311 of the second adapter piece 132 is welded to the third electrode 11', the third receiving groove 37' located at one end of the second side plate 31' along the second direction is used to accommodate the connecting portion 110 of the third electrode 11' and the first connecting portion 1311 of the second adapter piece 132. Since the third connecting portion 1411 of the fourth adapter piece 142 is welded to the fourth electrode 12', the third receiving groove 37' located at the other end of the second side plate 31' along the second direction is used to accommodate the connecting portion 110 of the fourth electrode 12' and the third connecting portion 1411 of the fourth adapter piece 142, thereby achieving insulation.

[0076] Therefore, when assembling the electrode assembly module 10 with the bracket 30, the electrode assembly module 10 can be directly snapped into the bracket 30, and the first connecting piece 15 and the connecting part 110 connected to the first connecting piece 15 can be snapped into the first receiving groove 34 located on the first side plate 31, and the second connecting piece 15' and the connecting part 110 connected to the second connecting piece 15' can be snapped into the first receiving groove 34 located on the second side plate 31'. At the same time, the connecting part 110 of the first electrode tab 11 and the first connecting part 1311 of the first adapter piece 131, and the connecting part 110 of the second electrode tab 12 and the third connecting part 141 can be snapped into the first receiving groove 34 located on the second side plate 31'. The connector 1411 is inserted into the second receiving groove 37, and the connecting portion 110 of the third electrode 11' and the first connecting portion 1311 of the second adapter piece 132, as well as the connecting portion 110 of the fourth electrode 12' and the third connecting portion 1411 of the fourth adapter piece 142 are inserted into the third receiving groove 37'. At this time, the second connecting portion 1312 of the first adapter piece 131 and the second connecting portion 1312 of the second adapter piece 132 extend toward the first adapter member 13, and the fourth connecting portion 1412 of the third adapter piece 141 and the fourth connecting portion 1412 of the fourth adapter piece 142 extend toward the second adapter member 14.

[0077] To prevent the first adapter piece 131, the second adapter piece 132, the third adapter piece 141, and the fourth adapter piece 142 from bending and shaking, which could affect the welding quality, such as Figure 11 As shown, a fourth receiving groove 35 is formed by an inward recess on one side of the third side plate 32 along the third direction, and a notch 38 is formed in the fourth receiving groove 35 at the position of the first electrode terminal 21. The fourth receiving groove 35 near the first side plate 31 is used to receive the first adapter piece 131, and the second connecting portion 1312 of the first adapter piece 131 extends out from the notch 38. The fourth receiving groove 35 near the second side plate 31' is used to receive the second adapter piece 132, and the second connecting portion 1312 of the second adapter piece 132 extends out from the notch 38 so as to be soldered to the first electrode terminal 21.

[0078] In some embodiments, a fifth receiving groove 36 is formed by recessing the fourth side plate 32' inward along a third direction. The fifth receiving groove 36 forms a notch 38 at the position of the second electrode terminal 22. The fifth receiving groove 36 near the first side plate 31 is used to receive the third adapter piece 141 and allows the fourth connecting portion 1412 of the third adapter piece 141 to extend out from the notch 38. The fifth receiving groove 36 near the second side plate 31' is used to receive the fourth adapter piece 142 and allows the fourth connecting portion 1412 of the fourth adapter piece 142 to extend out from the notch 38 so as to be welded to the second electrode terminal 22.

[0079] like Figure 13 As shown, in order to fix the welding slag, the battery cell also includes an insulating film 113, which can be a U-shaped adhesive. The first tab 111, the second tab 121, the third tab 112 and the fourth tab 122 all include a bent portion 114, wherein the bent portion 114 can be understood as a bent area that bends relative to the connecting portion 110. One end of the bent portion 114 is connected to the main body 101 of the battery cell, and the other end is connected to the connecting portion 110. The connecting portion 110 has a connecting end 1101 connected to the bent portion 114 and a free end 1102 disposed away from the connecting end 1101. The insulating film 113 covers at least the free end 1102 and the welding position, thereby fixing the welding slag. The welding positions are the first solder mark 151, the welding position of the first connecting portion 1311 of the first adapter piece 131 to the first tab 11, the welding position of the first connecting portion 1311 of the second adapter piece 132 to the third tab 11', the welding position of the third connecting portion 1411 of the third adapter piece 141 to the second tab 12, and the welding position of the third connecting portion 1411 of the fourth adapter piece 142 to the fourth tab 12'.

[0080] In some embodiments, such as Figure 14As shown, the bracket 30 is provided with weight-reduction holes 39 to reduce the weight of the bracket 30. The weight-reduction holes 39 can be through holes extending through the thickness direction of the side plates of the bracket 30, or they can be groove-shaped holes. Specifically, the first side plate 31, the second side plate 31', the third side plate 32 and / or the fourth side plate 32' are provided with weight-reduction holes 39, and multiple weight-reduction holes 39 are arranged at intervals to achieve overall weight reduction of the bracket 30.

[0081] Experiments, using a 150Ah LFP system with a single cell size of 1100mm*120mm*10mm as an example, show that a conventional 4C rechargeable battery cell experiences an internal temperature rise of 18℃ and an electrode terminal (i.e., electrode post) temperature rise of 27℃. In contrast, this application uses a battery cell formed by connecting 5 electrode assemblies in series (100), as shown in the following example... Figure 11 The structural arrangement shown results in a 12°C temperature rise inside the battery cell and an 8°C temperature rise at the electrode terminals (i.e., the terminals). It can be seen that the battery cell of this application can improve the temperature rise during the internal charging and discharging process of the battery, thereby enhancing battery safety.

[0082] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized by, include: The outer casing (20) has a receiving cavity, and the outer casing (20) has a first electrode terminal (21) and a second electrode terminal (22) respectively on opposite sides along the second direction; An electrode assembly module (10) is housed in the receiving cavity. The electrode assembly module (10) includes a plurality of electrode assemblies (100) connected in series. The electrode assembly module (10) has a first electrode tab (11) and a second electrode tab (12) on one side along a first direction. The electrode assembly module (10) has a third electrode tab (11') and a fourth electrode tab (12') on the other side along the first direction. The polarity of the first electrode tab (11) is opposite to that of the second electrode tab (12), the polarity of the third electrode tab (11') is opposite to that of the fourth electrode tab (12'), and the polarity of the first electrode tab (11) is the same as that of the third electrode tab (11'). The first adapter (13) connects the first electrode tab (11), the third electrode tab (11') and the first electrode terminal (21); The second adapter (14) connects the second electrode tab (12), the fourth electrode tab (12') and the second electrode terminal (22), wherein the first direction and the second direction are perpendicular to each other.

2. The battery cell according to claim 1, characterized in that, Multiple electrode assemblies (100) are arranged sequentially along the second direction. Each electrode assembly (100) includes a battery cell body (101). The battery cell body (101) has a first electrode tab (111) and a second electrode tab (121) protruding on one side of the first direction. The battery cell body (101) has a third electrode tab (112) and a fourth electrode tab (122) protruding on the other side of the first direction. In two adjacent electrode assemblies (100), the second electrode tab (121) of one electrode assembly (100) and the first electrode tab (111) of another electrode assembly (100) are arranged adjacently and electrically connected by a first connecting piece (15). The fourth electrode tab (122) of one electrode assembly (100) and the third electrode tab (112) of another electrode assembly (100) are arranged adjacently and electrically connected by a second connecting piece (15'). Among all the electrode assemblies (100), the first tab (111) closest to the first electrode terminal (21) is the first tab (11), the third tab (112) closest to the first electrode terminal (21) is the third tab (11'), the second tab (121) closest to the second electrode terminal (22) is the second tab (12), and the fourth tab (122) closest to the second electrode terminal (22) is the fourth tab (12').

3. The battery cell according to claim 2, characterized in that, Also includes: The bracket (30) includes a first side plate (31) and a second side plate (31') disposed opposite each other along a first direction. The first side plate (31) faces the side of the electrode assembly module (10) and is provided with a first positioning protrusion (33) corresponding to each cell body (101). The first positioning protrusion (33) abuts against the cell body (101); and / or, The second side plate (31') faces the side of the electrode assembly module (10) and is provided with a second positioning protrusion (33') corresponding to each cell body (101), and the second positioning protrusion (33') abuts against the cell body (101).

4. The battery cell according to claim 3, characterized in that, The first side plate (31) and the second side plate (31') are both recessed inward along the third direction to form a first receiving groove (34). The first pole lug (111), the second pole lug (121), the third pole lug (112) and the fourth pole lug (122) all include a connecting portion (110). The first receiving groove (34) on the first side plate (31) is used to receive the first connecting piece (15) and the connecting portion (110) connected to the first connecting piece (15). The first receiving groove (34) on the second side plate (31') is used to receive the second connecting piece (15') and the connecting portion (110) connected to the second connecting piece (15').

5. The battery cell according to claim 3 or 4, characterized in that, The first adapter component (13) includes a first adapter piece (131) and a second adapter piece (132). Both the first adapter piece (131) and the second adapter piece (132) include a first connecting portion (1311) and a second connecting portion (1312). The first connecting portion (1311) of the first adapter piece (131) is connected to the first electrode tab (11), and the first connecting portion (1311) of the second adapter piece (132) is connected to the third electrode tab (11'). The second connecting portions (1312) of both the first adapter piece (131) and the second adapter piece (132) are connected to the first electrode terminal (21). And / or, The second adapter component (14) includes a third adapter piece (141) and a fourth adapter piece (142). Both the third adapter piece (141) and the fourth adapter piece (142) include a third connecting portion (1411) and a fourth connecting portion (1412). The third connecting portion (1411) of the third adapter piece (141) is connected to the second electrode tab (12). The third connecting portion (1411) of the fourth adapter piece (142) is connected to the fourth electrode tab (12'). Both the fourth connecting portion (1412) of the third adapter piece (141) and the fourth connecting portion (1412) of the fourth adapter piece (142) are connected to the second electrode terminal (22).

6. The battery cell according to claim 5, characterized in that, One of the second connecting portions (1312) of the first adapter piece (131) and the second connecting portions (1312) of the second adapter piece (132) is provided with a latching protrusion (133), and the other is provided with a latching groove (134). The second connecting portions (1312) of the first adapter piece (131) and the second connecting portions (1312) of the second adapter piece (132) are locked and fixed by the engagement of the latching protrusion (133) and the latching groove (134); and / or, The fourth connecting part (1412) of the third adapter piece (141) and the fourth connecting part (1412) of the fourth adapter piece (142) are provided with a locking protrusion (133) and the other is provided with a locking groove (134). The fourth connecting part (1412) of the third adapter piece (141) and the fourth connecting part (1412) of the fourth adapter piece (142) are locked and fixed by the cooperation of the locking protrusion (133) and the locking groove (134).

7. The battery cell according to claim 5, characterized in that, The bracket (30) further includes a third side plate (32) and a fourth side plate (32') arranged opposite to each other along the second direction. The first side plate (31), the third side plate (32), the second side plate (31'), and the fourth side plate (32') are connected to form a frame structure. The first side plate (31) is recessed inward along one side of the third direction to form a second receiving groove (37), and the second receiving groove (37) located at one end of the first side plate (31) along the second direction is used to accommodate the connecting portion (110) of the first electrode (11) and the first connecting portion (1311) of the first adapter piece (131); the second receiving groove (37) located at the other end of the first side plate (31) along the second direction is used to accommodate the connecting portion (110) of the second electrode (12) and the third connecting portion (1411) of the third adapter piece (141); and / or, The second side plate (31') is recessed inward along the third direction to form a third receiving groove (37'), and the third receiving groove (37') located at one end of the second side plate (31') along the second direction is used to accommodate the connecting portion (110) of the third electrode (11') and the first connecting portion (1311) of the second adapter piece (132); the third receiving groove (37') located at the other end of the second side plate (31') along the second direction is used to accommodate the connecting portion (110) of the fourth electrode (12') and the third connecting portion (1411) of the fourth adapter piece (142).

8. The battery cell according to claim 7, characterized in that, Also includes: Insulating film (113), The first electrode tab (111), the second electrode tab (121), the third electrode tab (112) and the fourth electrode tab (122) all include a bent portion (114), the connecting portion (110) has a connecting end (1101) connected to the bent portion (114) and a free end (1102) disposed away from the connecting end (1101), and the insulating film (113) at least covers the free end (1102).

9. The battery cell according to claim 3, characterized in that, The bracket (30) is provided with weight reduction holes (39).

10. A battery, characterized in that, Includes the battery cell as described in any one of claims 1 to 9.

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