Pole electric connection structure, battery cell and power battery

Abstract

The utility model relates to a pole electric connection structure, a battery cell and a power battery. The pole electric connection structure comprises a connecting sheet, an insulating patch, a pole assembly, a tab assembly and two pole groups, in the assembling process of the pole electric connection structure, the battery cell and the power battery, the two positive tabs (or the two negative tabs) do not need to be directly connected, after the two positive tabs (or the two negative tabs) are connected through the connecting piece, the connecting piece is connected with the pole, and the pole is used for being connected with an external power supply or a power consumption part, so that the shape change of the pole tabs caused by bending of the pole tabs is avoided; the parameters and morphology of the tabs do not need to be detailedly designed, only the two positive tabs can be simultaneously connected with the connecting sheet (or the two negative tabs can be simultaneously connected with the connecting sheet), and the morphology of the pole group before connection only needs to meet the requirement that a pole electric connection structure can be mounted; and the pole group is attached before the two positive tabs are connected and before the two negative tabs are connected, so that the capacity of the battery cell is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a pole electrical connection structure, a battery cell and a power battery. Background Art

[0002] Lithium-ion batteries are widely used in transportation, energy storage, etc. due to their advantages of being green and environmentally friendly, high energy density, good cycle performance, low self-discharge rate, and no memory effect. Among them, power batteries are common in the transportation field. The packaging types of power batteries are mainly cylindrical, square, and soft pack.

[0003] Among them, square batteries have strong plasticity. Not only do they have a high grouping rate, but they can also be customized according to the specific needs of the products they carry. Due to their high flexibility, square batteries have been used in new energy vehicles for a long time. Car companies can customize the size of square batteries according to the needs of the models, so square batteries are generally considered to be the most suitable battery structure for new energy vehicles. With the increasing requirements for the energy density of battery cells, it is urgent to improve the internal space utilization of square battery cells.

[0004] At present, square batteries are generally used in Figure 1 The butterfly welding process shown is as follows: after ultrasonic welding of the connector 300 and the positive and negative pole ears 311 of the pole group 310 (the pole group 310 is spread out), the connector 300 and the cover plate are laser welded, and then the pole groups 300 on both sides are merged. Because the pole group 300 needs to be rotated during merging, sufficient bending space for the pole ears 311 needs to be reserved to prevent the pole ears 311 from tearing.

[0005] The above-mentioned square battery assembly process affects the battery cell capacity because a large space is required when the pole ear is bent. In addition, in this process, the length of the pole ear needs to be reserved before merging the electrode group and bending the pole ear, which makes the shape of the pole ear after bending difficult to control, and there is a risk of battery short circuit due to redundant pole ears. Utility Model Content

[0006] Based on this, it is necessary to provide a pole electrical connection structure, battery cell and power battery for the existing square battery assembly process, because a large space is required when the pole ear is bent, which affects the capacity of the battery cell. In addition, in this process, the length of the pole ear needs to be reserved before merging the pole group and bending the pole ear, which makes the shape of the pole ear after bending difficult to control. There is a risk of battery short circuit due to pole ear redundancy.

[0007] A pole electrical connection structure, the pole electrical connection structure comprising:

[0008] A connecting piece, comprising a pole connecting portion and a pole ear connecting portion connected to each other, wherein the pole ear connecting portion is used to connect to the positive pole ear or the negative pole ear of two matched pole groups;

[0009] An insulating patch, arranged on a side of the connecting piece close to the electrode group;

[0010] A pole assembly, one end of which is arranged in close contact with a side of the pole connecting portion away from the pole group.

[0011] In one embodiment, the tab connection portion includes a first connection arm and two second connection arms;

[0012] The two second connecting arms are respectively connected to two ends of the first connecting arm;

[0013] One side of the first connecting arm is connected to the two second connecting arms, and the other side is connected to the pole connecting portion.

[0014] The two second connecting arms are respectively used to be connected to the two positive electrode tabs or the two negative electrode tabs of the two electrode groups.

[0015] In one embodiment, the pole connection portion and the first connection arm are symmetrically arranged with respect to the plane where the fitting surfaces of the two pole groups are located; the two second connection arms are symmetrically arranged with respect to the plane where the fitting surfaces of the two pole groups are located;

[0016] An extending direction of the second connecting arm is perpendicular to an extending direction of the first connecting arm.

[0017] In one embodiment, the pole assembly includes a pole and a fixing ring, one end face of the pole is attached to and connected to the pole connecting portion, the fixing ring is sleeved on the pole and connected to the pole, and the fixing ring is used to connect to the cover plate.

[0018] In one embodiment, the pole assembly further includes a first plastic ring and a second plastic ring;

[0019] The first plastic ring is sleeved on the pole and connected to the pole, and the first plastic ring is attached between the pole connecting portion and the fixing ring;

[0020] The second plastic ring is sleeved on the pole and connected to the pole, and the second plastic ring is attached to a side of the fixing ring away from the first plastic ring.

[0021] An embodiment of the present application further provides a battery cell, the battery cell comprising two pole groups and two pole electrical connection structures; the two pole groups are respectively a first pole group and a second pole group, and the two pole electrical connection structures are respectively a first pole electrical connection structure and a second pole electrical connection structure;

[0022] The side surface of the first pole group is arranged in contact with the side surface of the second pole group;

[0023] The first pole electrical connection structure and the second pole electrical connection structure are respectively arranged on the end surfaces of the two pole groups;

[0024] The positive electrode ear of the first electrode group and the positive electrode ear of the second electrode group can be bent respectively so as to fit with the electrode ear connection portion of the first electrode column electrical connection structure;

[0025] The negative electrode tab of the first electrode group and the negative electrode tab of the second electrode group can be bent respectively so as to fit with the tab connection portion of the second electrode column electrical connection structure.

[0026] In one embodiment, the two positive electrode tabs are arranged along the arrangement direction of the two electrode groups, and the two negative electrode tabs are arranged along the arrangement direction of the two electrode groups.

[0027] In one embodiment, the negative electrode tab of the first electrode group and the negative electrode tab of the second electrode group are both laser welded to the electrode tab connection portion of the second electrode column electrical connection structure;

[0028] The positive electrode tab of the first electrode group and the positive electrode tab of the second electrode group are both laser welded to the electrode tab connection portion of the first electrode column electrical connection structure.

[0029] In one embodiment, the battery cell further comprises a bare aluminum plate and a plastic plate;

[0030] The plastic plate is bonded to the end faces of the two electrode groups at the same time, the bare aluminum plate is bonded to the side of the plastic plate away from the electrode group, and the connecting piece is located between the plastic plate and the electrode group;

[0031] The bare aluminum plate is provided with a first through hole and a second through hole, the plastic plate is provided with a third through hole and a fourth through hole, the pole assembly of the first pole electrical connection structure is passed through the first through hole and the third through hole, the pole assembly of the second pole electrical connection structure is passed through the second through hole and the fourth through hole, and the pole assembly is connected to the bare aluminum plate.

[0032] An embodiment of the present application further provides a power battery, which includes the battery cell.

[0033] In the above-mentioned power battery assembly process, firstly, two electrode groups are bonded, and one end of the electrode group provided with the pole ear faces the same direction, and each electrode group has a positive pole ear and a negative pole ear. Taking the positive electrode as an example, the pole column electrical connection structure is placed between the two positive pole ears and bonded to the electrode group, and the two positive pole ears are rotated and bent and bonded to the side of the pole ear connection part away from the electrode group, and then the positive pole ear is connected to the pole ear connection part, and the pole column assembly is located on the side of the pole column connection part away from the pole group and connected to the pole column connection part, and the insulating patch is located between the connecting piece and the connecting end face of the pole group, so as to prevent the connecting piece from being connected to the pole group and the pole ear at the same time to cause a short board, and the negative electrode is connected in the same way as the positive electrode, and finally the poles of the positive and negative electrodes of multiple cells are connected and the cells are packaged and assembled into a power battery. The above connection method eliminates the need for direct connection between the two positive pole ears (or two negative pole ears), and after being connected through a connecting piece, the connecting piece is connected to the pole column, which is used to connect to an external power supply or a power consumption part, thereby avoiding changes in the shape of the pole ears caused by bending of the pole ears, and there is no need to perform detailed design on the parameters and morphology of the pole ears. It is only necessary to ensure that the two positive pole ears can be connected to the connecting piece at the same time (or the two negative pole ears can be connected to the connecting piece at the same time). The morphology of the pole group before connection only needs to meet the requirement of being able to install the pole column electrical connection structure. The pole group has been fitted before the two positive pole ears are connected and before the two negative pole ears are connected, thereby increasing the capacity of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of butterfly welding process.

[0035] Figure 2 Schematic diagram of the structure of the pole electrical connection structure of an embodiment.

[0036] Figure 3 for Figure 2 Cross-sectional view of the pole electrical connection structure.

[0037] Figure 4 for Figure 1 Schematic diagram of the structure of the pole electrical connection structure and the connection between the pole ear and the pole group.

[0038] Figure 5 Schematic diagram of the structure of a battery cell according to an embodiment.

[0039] Figure 6 for Figure 5 Schematic diagram of the structure of Zhongguang aluminum plate and plastic plate.

[0040] Description of Figure Numbers:

[0041] 100-pole electrical connection structure;

[0042] 110-connecting piece; 111-pole connecting portion; 112-pole ear connecting portion; 113-first connecting arm; 114-second connecting arm;

[0043] 120-Insulation patch;

[0044] 130-pole assembly; 131-pole; 132-fixing ring; 133-first plastic ring; 134-second plastic ring; 135-sealing ring;

[0045] 141- positive electrode ear; 142- negative electrode ear;

[0046] 150-first pole group; 151-second pole group; 152-first pole column electrical connection structure; 153-second pole column electrical connection structure;

[0047] 200-battery cells;

[0048] 210-pole group; 211-pole ear; 212-connecting end surface; 213-aluminum plate; 214-plastic plate; 215-first through hole; 216-second through hole; 217-third through hole; 218-fourth through hole;

[0049] 300-connecting piece; 310-pole group; 311-pole ear. DETAILED DESCRIPTION

[0050] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0051] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0052] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0053] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0054] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0055] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0056] The pole electrical connection structure 100 of the present application is applicable to two bonded pole groups 210 of a power battery. The pole electrical connection structure 100 is connected to the positive pole ear 141 of the pole group 210 or to the negative pole ear 142. One end surface of the two bonded pole groups 210 is located in the first plane and forms a Figure 4 The connecting end face 212 is shown.

[0057] See also Figure 2 , Figure 2 A schematic structural diagram of a pole electrical connection structure 100 in an embodiment of the present application is shown. The pole electrical connection structure 100 provided in an embodiment of the present application includes: a connecting piece 110 , an insulating patch 120 and a pole assembly 130 .

[0058] In the above-mentioned pole electrical connection structure 100, the connecting piece 110 includes a pole connecting portion 111 and a pole ear connecting portion 112 connected to each other, and the pole ear connecting portion 112 is used to connect to the positive pole ear 141 or the negative pole ear 142 of the two matched pole groups, wherein one end surface of the two matched pole groups 210 is in the first plane, and forms the following Figure 4 The connecting end face 212 is shown. The insulating patch 120 is arranged on the side of the connecting piece 110 close to the electrode group 210. One end of the pole assembly 130 is arranged on the side of the pole connecting portion 111 away from the electrode group 210.

[0059] See also Figure 2-4 In the process of assembling and connecting the above-mentioned pole electrical connection structure 100 with the pole group 210, the two pole groups 210 are firstly fitted together, and one end of the pole group 210 provided with the pole ear 211 faces the same direction, and each pole group 210 has a positive pole ear 141 and a negative pole ear 142. Taking the positive pole as an example, the pole electrical connection structure 100 is placed between the two positive pole ears 141 and fits with the pole group 210, and the two positive pole ears 141 are connected to the pole ear connection part 112. The pole assembly 130 is located on the side of the pole connection part 111 away from the pole group 210 and connected to the pole connection part 111. The insulating patch 120 is located between the connecting piece 110 and the connecting end face 212 of the pole group 210, so as to prevent the connecting piece 110 from being connected to the pole group 210 and the pole ear at the same time, resulting in a short plate. The negative pole is connected in the same way as the positive pole. The above-mentioned connection method makes it unnecessary for the two positive pole ears 141 (or the two negative pole ears 142) to be directly connected, and after being connected through the connecting sheet 110, the connecting sheet 110 is connected to the pole assembly 130, and the pole assembly 130 is used to connect to an external power supply or a power consumption part, thereby avoiding the change of the pole ear morphology caused by the bending of the pole ear 211, and there is no need to design the parameters and morphology of the pole ear 211 in detail, and it is only necessary to meet the requirements that the two positive pole ears 141 can be connected to the connecting sheet 110 at the same time (or the two negative pole ears 142 can be connected to the connecting sheet 110 at the same time), and the morphology of the pole group 210 before the connection only needs to meet the requirements of being able to install the pole electrical connection structure 100, and the pole group 210 has been completed before the two positive pole ears 141 are connected and before the two negative pole ears 142 are connected, thereby increasing the capacity of the battery cell 200.

[0060] See also Figure 2-4In one embodiment, the pole ear connection portion 112 includes a first connection arm 113 and two second connection arms 114. One side of the first connection arm 113 is connected to the two second connection arms 114, and the other side is connected to the pole connection portion 111, and the two second connection arms 114 are respectively connected to the two ends of the first connection arm 113. The two second connection arms 114 are respectively used to connect to the two positive pole ears 141 or the two negative pole ears 142 of the two pole groups 210 that are attached.

[0061] In this embodiment, the two positive electrode tabs 141 (or the two negative electrode tabs 142) are respectively connected to the two second connecting arms 114 and then connected to the pole connecting portion 111 through the first connecting arm 113 and finally connected to the pole assembly 130, thereby shortening the length of the tab along the arrangement direction of the pole group 210. This makes the space required for the tab 211 to be bent and connected to the connecting sheet 110 smaller, thereby increasing the volume of the pole group 210 and the capacity of the battery cell 200.

[0062] See also Figure 2-4 In one embodiment, the pole connecting portion 111 and the first connecting arm 113 are symmetrically arranged about the plane where the fitting surfaces of the two pole groups 210 are located. The extension direction of the second connecting arm 114 is perpendicular to the extension direction of the first connecting arm 113, and the two second connecting arms 114 are symmetrically arranged about the plane where the fitting surfaces of the two pole groups 210 are located. As a result, the distances between the two second connecting arms 114 and the corresponding pole ears are equal, and the distances between the pole 131 and the two positive pole ears 141 (or the two negative pole ears 142) are equal, so that the power transmission paths from the two pole groups 210 to the pole 131 are equal, thereby ensuring the synchronous charging and discharging of different battery cells 200, making the charging and discharging of the entire power battery more regular, and ensuring the stable charging and discharging of the power battery.

[0063] See also Figure 2-4 In one embodiment, the pole assembly 130 includes a pole 131 and a fixing ring 132. One end surface of the pole 131 is attached to and connected to the pole connecting portion 111. The fixing ring 132 is sleeved on the pole 131 and connected to the pole 131. In this embodiment, the fixing ring 132 is used to connect to the cover plate, so that the pole 131 is connected to the battery cover plate through the fixing ring 132.

[0064] See also Figure 2-4In one embodiment, the pole assembly 130 further includes a first plastic ring 133 and a second plastic ring 134. The first plastic ring 133 is sleeved on the pole 131 and connected to the pole 131, and the first plastic ring 133 is attached between the pole connection portion 111 and the fixing ring 132. The second plastic ring 134 is sleeved on the pole 131 and connected to the pole 131, and the second plastic ring 134 is attached to the side of the fixing ring 132 away from the first plastic ring 133. Thus, the fixing ring 132 is clamped between the first plastic ring 133 and the second plastic ring 134, so that the fixing ring 132 is only connected to the cover plate, thereby avoiding abnormal charging and discharging of the battery cell 200 caused by the fixing ring 132 contacting other structures.

[0065] Preferably, the pole assembly 130 also includes a sealing ring 135, which is sleeved on the pole 131 and located between the pole 131 and the fixing ring 132, thereby sealing the interior of the battery cell 200. At the same time, the fixing ring 132 is connected to the pole 131 in an insulating manner to prevent the pole 131 and the fixing ring 132 from being energized with each other.

[0066] Specifically, the fixing ring 132 is an aluminum ring.

[0067] See also Figure 2-4 , an embodiment of the present application further provides a battery cell 200, the battery cell 200 includes two pole groups 210 and two pole column electrical connection structures 100. The two pole groups 210 are respectively a first pole group 150 and a second pole group 151, the two pole column electrical connection structures 100 are respectively a first pole column electrical connection structure 152 and a second pole column electrical connection structure 153, and the sides of the first pole group 150 and the second pole group 151 are arranged in affixed relation. The first pole column electrical connection structure 152 and the second pole column electrical connection structure 153 are respectively arranged on the end faces of the two pole groups 210, that is, the connecting end faces 212, and the positive pole ear 141 of the first pole group 150 and the positive pole ear 141 of the second pole group 151 can be bent respectively so as to fit with the pole ear connection portion 112 of the first pole column electrical connection structure 152;

[0068] The negative electrode tab 142 of the first electrode group 150 and the negative electrode tab 142 of the second electrode group 151 can be bent respectively so as to fit with the tab connection portion 112 of the second electrode column electrical connection structure 153 .

[0069] During the installation of the battery cell 200, the two electrode groups 210 are firstly attached, and the ends of the electrode groups 210 provided with the electrode ears face the same direction, and each electrode group 210 has a positive electrode ear 141 and a negative electrode ear 142. Taking the positive electrode as an example, the first pole column electrical connection structure 152 is placed between the positive electrode ear 141 of the first pole group 150 and the positive electrode ear 141 of the second pole group 151, and is simultaneously attached to the connection end surface 212 of the first pole group 150 and the second pole group 151, and the positive electrode ear 141 of the first pole group 150 and the positive electrode ear 141 of the second pole group 151 are rotated and bent and attached to the side of the electrode ear connection portion 112 away from the pole group 210, and then the positive electrode ear 141 is attached to the first pole column electrical connection structure 152. The pole ear connecting portion 112 of the connection structure 152 is connected, the pole 131 of the first pole electrical connection structure 152 is placed on the side of the pole connecting portion 111 away from the first pole group 150 and the second pole group 151, and is connected to the pole connecting portion 111, and the insulating patch 120 is located between the connecting piece 110 and the connecting end surface 212 of the pole group 210, so as to prevent the connecting piece 110 from being connected to the pole group 210 and the pole ear at the same time to cause a short board, and the negative and positive connection methods are the same, which will not be repeated here. The above-mentioned connection method makes it unnecessary for the two positive pole ears 141 (or the two negative pole ears 142) to be directly connected. After the positive pole ears 141 (or the two negative pole ears 142) are connected through the connecting sheet 110, the connecting sheet 110 is connected to the pole 131. The pole 131 is used to connect to an external power supply or a power consumption part, thereby avoiding the change in the shape of the pole ear 211 caused by the bending of the pole ear, and there is no need to perform detailed design on the parameters and morphology of the pole ear 211. It is only necessary to ensure that the two positive pole ears 141 can be connected to the connecting sheet 110 (or the two negative pole ears 142 can be connected to the connecting sheet 110) at the same time. The morphology of the pole group 210 before the connection also only needs to meet the requirement of being able to install the pole electrical connection structure 100. Before the two positive pole ears 141 are connected and before the two negative pole ears 142 are connected, the pole group 210 has been fitted, thereby increasing the capacity of the battery cell 200.

[0070] See also Figure 2-4 In one embodiment, the two positive pole ears 141 are arranged along the arrangement direction of the two pole groups 210, and the two negative pole ears 142 are arranged along the arrangement direction of the two pole groups 210. The electrical connection distance between the pole 131 and the two positive pole ears 141 (or the two negative pole ears 142) through the connecting sheet 110 is equal, so that the power transmission path from the two pole groups 210 to the pole 131 is equal, thereby ensuring the synchronous charging and discharging of different battery cells 200, making the charging and discharging logic of the entire power battery more regular, and ensuring the stable charging and discharging of the power battery.

[0071] See also Figure 2-4In one embodiment, the negative electrode ear 142 of the first electrode group 150 and the negative electrode ear 142 of the second electrode group 151 are both laser welded to the electrode ear connection portion 112 of the second electrode column electrical connection structure 153, and the positive electrode ear 141 of the first electrode group 150 and the positive electrode ear 141 of the second electrode group 151 are both laser welded to the electrode ear connection portion 112 of the first electrode column electrical connection structure 152, so that the thickness of the positive electrode ear 141 (or the negative electrode ear 142) and the electrode ear connection portion 112 is minimized, avoiding other connection methods from increasing the thickness of the positive electrode ear 141 (or the negative electrode ear 142) and the electrode ear connection portion 112.

[0072] See also Figure 2-6 In one embodiment, the battery cell 200 further includes a bare aluminum plate 213 and a plastic plate 214. The plastic plate 214 is bonded to the end faces of the two pole groups 210 at the same time, the bare aluminum plate 213 is bonded to the side of the plastic plate 214 away from the pole group 210, and the connecting piece 110 is located between the plastic plate 214 and the pole group 210. The bare aluminum plate 213 is provided with a first through hole 215 and a second through hole 216, and the plastic plate 214 is provided with a third through hole 217 and a fourth through hole 218, wherein one pole assembly 130 is penetrated through the first through hole 215 and the third through hole 217, the pole assembly 130 of the first pole electrical connection structure 152 is penetrated through the second through hole 216 and the fourth through hole 218, and the pole assembly 130 of the second pole electrical connection structure 153 is connected to the bare aluminum plate 213.

[0073] In this embodiment, the connection end face 212 of the battery cell 200 is covered by the bare aluminum plate 213, and the plastic plate 214 is located between the bare aluminum plate 213 and the electrode group 210, thereby avoiding the bare aluminum plate 213 from being connected to the electrode group 210 and the pole 131, preventing the bare aluminum plate 213 from discharging. At the same time, the aluminum cover plate reduces the overall weight and prevents internal corrosion of the battery cell 200.

[0074] An embodiment of the present application further provides a power battery, the power battery including a battery cell 200 .

[0075] During the assembly of the power battery, two electrode groups 210 are firstly attached, and the ends of the electrode groups 210 provided with the electrode tabs face the same direction. Each electrode group 210 has a positive electrode tab 141 and a negative electrode tab 142 . Taking the positive electrode as an example, the pole electrical connection structure 100 is placed between the two positive pole ears 141 and fit with the pole group 210, and the two positive pole ears 141 are rotated and bent and fit to the side of the pole ear connection part 112 away from the pole group 210, and then the positive pole ear 141 is connected to the pole ear connection part 112. The pole assembly 130 is located on the side of the pole connection part 111 away from the pole group 210 and connected to the pole connection part 111. The insulating patch 120 is located between the connecting piece 110 and the connecting end face 212 of the pole group 210, so as to prevent the connecting piece 110 from being connected to the pole group 210 and the pole ear at the same time, resulting in a short board. The negative electrode is connected in the same way as the positive electrode. Finally, the positive and negative poles 131 of multiple battery cells 200 are connected and the battery cells 200 are packaged and assembled into a power battery. The above-mentioned connection method makes it unnecessary for the two positive pole ears 141 (or the two negative pole ears 142) to be directly connected, and after being connected through the connecting sheet 110, the connecting sheet 110 is connected to the pole 131, and the pole 131 is used to connect to an external power supply or a power consumption part, thereby avoiding the change of the pole ear shape caused by the bending of the pole ear, and there is no need to design the parameters and morphology of the pole ear in detail, and it is only necessary to meet the requirements that the two positive pole ears 141 can be connected to the connecting sheet 110 at the same time (or the two negative pole ears 142 can be connected to the connecting sheet 110 at the same time), and the morphology of the pole group 210 before the connection only needs to meet the requirements of being able to install the pole electrical connection structure 100, and the pole group 210 has been completed before the two positive pole ears 141 are connected and before the two negative pole ears 142 are connected, thereby increasing the capacity of the battery cell 200.

[0076] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A pole electrical connection structure, characterized in that: The pole electrical connection structure comprises: A connecting piece, comprising a pole connecting portion and a pole ear connecting portion connected to each other, wherein the pole ear connecting portion is used to connect to the positive pole ear or the negative pole ear of two matched pole groups; An insulating patch, arranged on a side of the connecting piece close to the electrode group; A pole assembly, one end of which is arranged in close contact with a side of the pole connecting portion away from the pole group.

2. The pole electrical connection structure according to claim 1, characterized in that: The pole lug connecting portion includes a first connecting arm and two second connecting arms; The two second connecting arms are respectively connected to two ends of the first connecting arm; One side of the first connecting arm is connected to the two second connecting arms, and the other side is connected to the pole connecting portion. The two second connecting arms are respectively used to be connected to the two positive electrode tabs or the two negative electrode tabs of the two electrode groups.

3. The pole electrical connection structure according to claim 2, characterized in that: The pole connection portion and the first connection arm are symmetrically arranged with respect to the plane where the fitting surfaces of the two pole groups are located; the two second connection arms are symmetrically arranged with respect to the plane where the fitting surfaces of the two pole groups are located; An extending direction of the second connecting arm is perpendicular to an extending direction of the first connecting arm.

4. The pole electrical connection structure according to claim 1, characterized in that: The pole assembly comprises a pole and a fixing ring, one end of the pole is attached to and connected with the pole connecting portion, the fixing ring is sleeved on the pole and connected with the pole, and the fixing ring is used to be connected with the cover plate.

5. The pole electrical connection structure according to claim 4, characterized in that: The pole assembly also includes a first plastic ring and a second plastic ring; The first plastic ring is sleeved on the pole and connected to the pole, and the first plastic ring is attached between the pole connecting portion and the fixing ring; The second plastic ring is sleeved on the pole and connected to the pole, and the second plastic ring is attached to a side of the fixing ring away from the first plastic ring.

6. A battery cell, characterized in that: The battery cell comprises two pole groups and two pole electrical connection structures according to any one of claims 1 to 5; the two pole groups are respectively a first pole group and a second pole group, and the two pole electrical connection structures are respectively a first pole electrical connection structure and a second pole electrical connection structure; The side surface of the first pole group is arranged in contact with the side surface of the second pole group; The first pole electrical connection structure and the second pole electrical connection structure are respectively arranged on the end surfaces of the two pole groups; The positive electrode ear of the first electrode group and the positive electrode ear of the second electrode group can be bent respectively so as to fit with the electrode ear connection portion of the first electrode column electrical connection structure; The negative electrode tab of the first electrode group and the negative electrode tab of the second electrode group can be bent respectively so as to fit with the tab connection portion of the second electrode column electrical connection structure.

7. The battery cell according to claim 6, characterized in that: The two positive electrode tabs are arranged along the arrangement direction of the two electrode groups, and the two negative electrode tabs are arranged along the arrangement direction of the two electrode groups.

8. The battery cell according to claim 6, characterized in that: The negative electrode ear of the first electrode group and the negative electrode ear of the second electrode group are laser welded to the electrode ear connection part of the second electrode column electrical connection structure; The positive electrode tab of the first electrode group and the positive electrode tab of the second electrode group are both laser welded to the electrode tab connection portion of the first electrode column electrical connection structure.

9. The battery cell according to claim 6, characterized in that: The battery core also includes a bare aluminum plate and a plastic plate; The plastic plate is bonded to the end faces of the two electrode groups at the same time, the bare aluminum plate is bonded to the side of the plastic plate away from the electrode group, and the connecting piece is located between the plastic plate and the electrode group; The bare aluminum plate is provided with a first through hole and a second through hole, the plastic plate is provided with a third through hole and a fourth through hole, the pole assembly of the first pole electrical connection structure is passed through the first through hole and the third through hole, the pole assembly of the second pole electrical connection structure is passed through the second through hole and the fourth through hole, and the pole assembly is connected to the bare aluminum plate.

10. A power battery, characterized in that: The power battery comprises the battery cell according to any one of claims 6 to 9.

Images