Battery cells and batteries
By using an insulating support and conductive plate to connect the tabs of the electrode core in the blade battery, and by using a solid electrolyte, the problems of excessive current carrying capacity and temperature rise are solved, thus achieving high energy density and improved safety of the battery.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG ZEEKR INTELLIGENT TECH CO LTD
- Filing Date
- 2025-07-11
- Publication Date
- 2026-07-03
AI Technical Summary
Excessive current carrying capacity and temperature rise in blade batteries lead to performance degradation and failure of safety structures.
The positive and negative tabs of the electrode core are connected by an insulating bracket and a conductive plate. The current carrying capacity and temperature rise of the tabs are reduced by series connection, and the energy density of the battery is improved by using a solid electrolyte.
It effectively reduces the current carrying capacity and temperature rise of the tabs, improves the energy density and safety of the battery, and avoids problems caused by short circuits and increased creepage space.
Smart Images
Figure CN224458475U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, specifically providing a battery cell and a battery. Background Technology
[0002] Due to its advantages such as high safety, high space utilization, and long service life, blade batteries are increasingly replacing ordinary batteries in existing electric vehicles. However, because blade batteries have a large cell capacity, they are prone to higher current carrying capacity and temperature rise, which can lead to performance degradation and safety structure failure. Summary of the Invention
[0003] This application aims to solve the aforementioned technical problems, namely, to address the issues of excessive current carrying capacity and temperature rise in existing blade batteries.
[0004] This application provides a battery cell, comprising: at least two electrode cores, each of the at least two electrode cores being provided with a positive electrode tab and a negative electrode tab, and the at least two electrode cores being connected in series along the length direction of the battery cell; and a connector being disposed between two adjacent electrode cores, wherein the positive electrode tab of one of the two adjacent electrode cores is welded to the negative electrode tab of the other electrode core to the connector.
[0005] In the above-mentioned optional technical solutions for the battery cell, the connector includes an insulating support and a conductive plate. The insulating support is provided with a mounting hole, and the conductive plate is disposed in the mounting hole. The two opposing surfaces of the conductive plate are exposed from the mounting hole, and the two opposing surfaces of the conductive plate are respectively connected to the positive electrode tab of one of the two adjacent electrode cores and the negative electrode tab of the other electrode core.
[0006] In the above-mentioned optional technical solution for the battery cell, both opposite surfaces of the insulating bracket are provided with grooves, and the mounting hole is provided at the bottom of the grooves to connect the two grooves. The positive electrode tab and the negative electrode tab connected to the conductive plate are respectively provided in the two grooves.
[0007] In the optional technical solutions of the above-mentioned battery cell, the battery cell further includes a polyester film, which wraps around the outside of the connector and the positive and negative tabs connected to the connector, so as to insulate the conductive plate and the positive and negative tabs connected to the conductive plate from other conductive components inside the battery cell.
[0008] In the above-mentioned optional technical solutions for the battery cell, the battery cell further includes a housing, the at least two poles and the connector are disposed in the housing, the housing is provided with an explosion-proof valve, the at least two poles include a positive end tab and a negative end tab located at both ends and not connected to the connector, and the distance between the positive end tab and the negative end tab and the explosion-proof valve along the length direction of the at least two poles is greater than or equal to 15mm.
[0009] In the above-mentioned optional technical solutions for the battery cell, multiple explosion-proof valves are provided, and each of the multiple explosion-proof valves corresponds one-to-one with the at least two electrode cores. Along the length direction of the at least two electrode cores, the distance between the positive electrode tab and the negative electrode tab of each explosion-proof valve and the electrode core corresponding to the explosion-proof valve is greater than or equal to 15mm.
[0010] In the above-mentioned optional technical solutions for the battery cell, the battery cell further includes an electrolytic medium, which is configured as a solid electrolytic medium.
[0011] In the optional technical solutions of the above-mentioned battery cell, the battery cell also includes tab adhesive, which is wrapped around the outside of the positive tab and the negative tab, and the tab adhesive is one of polyimide tape and polyester tape.
[0012] In the above-mentioned optional technical solutions for the battery cell, the insulating support is made of plastic; and / or, the conductive plate is made of copper-aluminum composite plate.
[0013] This application also provides a battery, comprising: a casing; and a battery cell as described in any of the above technical solutions, wherein the battery cell is disposed within the casing.
[0014] When the above technical solution is adopted, under the same stacking condition, the longer the cell, the larger the capacity. Since the current carrying capacity is proportional to the capacity, the larger the capacity, the greater the current that the tab needs to carry. By dividing the long cell into multiple parts along the length direction and connecting them in series, the capacity of each part of the cell is reduced accordingly. Therefore, the current that the tab needs to carry is reduced accordingly, and the temperature of the tab is lower. Thus, the current carrying capacity and temperature rise of a single tab are reduced when at least two cells are connected in series. Attached Figure Description
[0015] The preferred embodiments of this application are described below with reference to the accompanying drawings, in which:
[0016] Figure 1 This is a cross-sectional view of the battery cell of this application;
[0017] Figure 2 This is a schematic diagram showing the polyester film disposed at the tab position of the battery cell of this application;
[0018] Figure 3 This is a schematic diagram of the connector for the battery cell in this application;
[0019] Figure 4 This is a cross-sectional view of the battery cell of this application with an explosion-proof valve installed;
[0020] Figure 5 This is a schematic diagram of the electrode tab setting adhesive of the battery cell of this application.
[0021] List of reference numerals in the attached diagram:
[0022] 1. Battery cell; 11. First electrode core; 12. Second electrode core; 111. Positive electrode tab; 1111. End positive electrode tab; 112. Negative electrode tab; 1121. End negative electrode tab; 13. Connector; 130. Insulating bracket; 131. Groove; 132. Mounting hole; 133. Conductive plate; 1331. Copper plate; 1332. Aluminum plate; 14. Polyester film; 15. Housing; 16. Explosion-proof valve; 17. Electrode adhesive. Detailed Implementation
[0023] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. In the following description relating to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The terms “first,” “second,” and similar terms used in this specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. “A plurality of” means two or more.
[0024] Unless otherwise stated, the orientation or positional relationship indicated by “length”, “inner”, and “outer” is based on the orientation or positional relationship shown in the accompanying drawings and is only for the purpose of facilitating the description of this application and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0025] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intervening element. Furthermore, "connection" should be interpreted broadly; for example, it can be a fixed connection, a detachable connection, or an integral 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 a connection within two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0026] It should be noted that, Figure 1 , Figure 5In the figure, the x-direction is the length direction of cell 1, and also the length direction of the electrode core.
[0027] Combination Figures 1 to 5 This application provides a battery cell 1, including a connector 13 and at least two pole pieces. Each of the at least two pole pieces is provided with a positive tab 111 and a negative tab 112, and the at least two pole pieces are connected in series along the length direction of the battery cell 1. The connector 13 is disposed between two adjacent pole pieces, and the positive tab 111 of one pole piece and the negative tab 112 of the other pole piece are welded to the connector 13.
[0028] For ease of explanation, the following example uses at least two electrode cores, including a first electrode core 11 and a second electrode core 12, and takes the example of the positive tab 111 of the first electrode core 11 and the negative tab 112 of the second electrode core 12 being welded together by a connector 13. In this case, the first electrode core 11 and the second electrode core 12 are connected in series. Alternatively, when the at least two electrode cores consist only of the first electrode core 11 and the second electrode core 12, the negative tab 112 of the first electrode core 11 and the positive tab 111 of the second electrode core 12 are located at both ends of the cell 1. Therefore, the negative tab 112 of the first electrode core 11 can be called the end negative tab 1121, and the positive tab 111 of the second electrode core 12 can be called the end positive tab 1111.
[0029] In existing technologies, when two electrode cores are connected in series, each electrode core has an end cap, and an intermediate connecting portion is provided between the end caps. The two electrode cores are connected in series through the end caps and the intermediate connecting portion. In this case, due to the end caps, the distance between the positive tab 111 and the negative tab 112 connected to the intermediate connecting portion increases, thereby increasing the creepage space. This application, by directly welding the first electrode core 11 and the second electrode core 12 to the connector 13, can ensure the electrical connection between the positive tab 111 of the first electrode core 11 and the negative tab 112 of the second electrode core 12. Since the corresponding end caps for the first electrode core 11 and the second electrode core 12 do not need to be provided, the distance between the positive tab 111 of the first electrode core 11 and the negative tab 112 of the second electrode core 12 can also be reduced, making the connection between adjacent electrode cores more compact, thereby reducing the creepage space of the cell 1 and thus increasing the energy density of the cell 1.
[0030] Furthermore, when cell 1 is the blade cell 1 within a blade battery, under the same stacking conditions, the longer the blade cell 1 is, the larger the capacity of the blade battery. Since the current carrying capacity of the tabs is directly proportional to the capacity, the larger the capacity, the greater the current that the tabs (collectively referred to as the positive tab 111 and the negative tab 112) need to carry. Consequently, the temperature of the tabs will be higher. Taking the example of dividing the long blade cell 1 into two parts and connecting them in series, the capacity of each part of cell 1 is halved. In this case, the current carrying capacity of the tabs corresponding to each part of cell 1 is halved, and therefore, the temperature of the tabs corresponding to them also decreases accordingly.
[0031] It should be noted that the number of electrode cores in this application can be set according to the needs of those skilled in the art, and can be two or more. In addition, for the sake of convenience, the following description will use at least two electrode cores, including two, namely the first electrode core 11 and the second electrode core 12, as an example.
[0032] In one embodiment, combined with Figure 1 and Figure 2 The connector 13 includes an insulating bracket 130 and a conductive plate 133. The insulating bracket 130 is provided with a mounting hole 132, and the conductive plate 133 is disposed in the mounting hole 132. The two opposing surfaces of the conductive plate 133 protrude from the mounting hole 132. The two opposing surfaces of the conductive plate 133 are respectively connected to the positive electrode tab 111 of one of the two adjacent electrode cores and the negative electrode tab 112 of the other electrode core. That is, the two opposing surfaces of the conductive plate 133 are respectively connected to the positive electrode tab 111 of the first electrode core 11 and the negative electrode tab 112 of the second electrode core 12. Since the positive electrode tab 111 is made of aluminum and the negative electrode tab 112 is made of copper, in order to avoid electrochemical corrosion during copper-aluminum welding, or because copper and aluminum cannot be directly welded due to their different melting points, it is necessary to use the intermediate conductive plate 133 to weld to the aluminum positive electrode tab 111 and the copper negative electrode tab 112 respectively. When the positive tab 111 of the first electrode 11 and the negative tab 112 of the second electrode 12 are respectively connected to the conductive plate 133, the insulating bracket 130 can separate the first electrode 11 and the second electrode 12. At the same time, the insulating bracket 130 can also fix the conductive plate 133 through the mounting hole 132 to support the conductive plate 133.
[0033] It should be noted that the insulating bracket 130 can be made of plastic, which provides excellent insulation.
[0034] It should also be noted that the reference Figure 2 The conductive plate 133 can be set as a copper-aluminum composite plate. The copper plate 1331 in the copper-aluminum composite plate is welded to the negative electrode tab 112, and the aluminum plate 1332 is welded to the positive electrode tab 111. This can ensure the welding effect and avoid electrochemical corrosion between different materials. Therefore, using a copper-aluminum composite plate as the conductive plate 133 can ensure that both the positive electrode tab 111 and the negative electrode tab 112 can be effectively and stably connected to the copper-aluminum composite plate.
[0035] In addition, the positive electrode tab 111 and the negative electrode tab 112 are preferably welded to the copper-aluminum composite plate by laser welding. Compared with other welding methods, laser welding has higher precision, can increase welding speed and thus increase efficiency, and can also increase the connection strength at the welding position.
[0036] In one embodiment, the combination continues. Figure 1 and Figure 2The insulating bracket 130 has grooves 131 on both opposite sides, and mounting holes 132 are provided at the bottom of the grooves 131 to connect the two grooves 131. The positive electrode tab 111 and the negative electrode tab 112, which are connected to the conductive plate 133, are respectively provided in the two grooves 131. The grooves 131 on both sides of the insulating bracket 130 can respectively accommodate the positive electrode tab 111 of the first electrode core 11 and the negative electrode tab 112 of the second electrode core 12, thereby ensuring that the positive electrode tab 111 of the first electrode core 11 and the negative electrode tab 112 of the second electrode core 12 can be effectively protected. At the same time, the grooves 131 can also position the positive electrode tab 111 of the first electrode core 11 and the negative electrode tab 112 of the second electrode core 12, thereby ensuring that the welding position of the two to the conductive plate 133 is accurate. In addition, when it is necessary to insulate and seal the connector 13, the positive tab 111 of the first electrode core 11 and the negative tab 112 of the second electrode core 12, the gap between the groove 131 and the positive tab 111 and the negative tab 112 can be insulated and sealed to effectively ensure that the positive tab 111 and the negative tab 112 are effectively insulated from the conductive components in the battery cell 1.
[0037] In one embodiment, reference Figure 5 The battery cell 1 also includes tab adhesive 17, which is wrapped around the outside of the positive tab 111 and the negative tab 112. The tab adhesive 17 is one of polyimide tape (PI tape) or polyester tape (PET tape). Since tab adhesive 17 is provided on the outside of all tabs, therefore... Figure 5 The diagram illustrates the use of tab adhesive 17 on the positive tab 111 of the first electrode core 11 as an example. Tab adhesive 17 mainly wraps around the base of the positive tab 111 and the negative tab 112, protecting and fixing the tabs to prevent them from breaking during operation. At the same time, tab adhesive 17 also insulates the tabs from other conductive parts of the battery cell 1, thus preventing short circuits caused by the tabs conducting electricity with other conductive parts during operation.
[0038] In one embodiment, reference Figure 3The battery cell 1 also includes a polyester film 14, which wraps around the connector 13 and the positive electrode 111 and negative electrode 112 connected to the connector 13, so that the conductive plate 133 and the positive electrode 111 and negative electrode 112 connected to the conductive plate 133 are insulated from other conductive components in the battery cell 1. Since the insulating support 130 of the connector 13 is insulated, the polyester film 14 wrapped in the above-mentioned position is mainly used to insulate the conductive plate 133 and the positive electrode 111 and negative electrode 112 connected to the conductive plate 133 from other conductive components in the cell 1. The polyester film 14 is heat-fused to cover the positive electrode 111 of the first electrode core 11, the negative electrode 112 of the second electrode core 12 and the exposed part of the conductive plate 133, so that the positive electrode 111 and negative electrode 112 at this position can be insulated from other conductive components in the cell 1, thereby avoiding the problem of short circuit caused by the positive electrode 111 or negative electrode 112 conducting with other conductive components during the operation of the cell 1.
[0039] It should be noted that the positive tab 111 and negative tab 112 connected to the connector 13 are insulated from other conductive components inside the battery cell 1 by being covered with a polyester film 14. Since the battery cell 1 is provided with a housing 15, and the negative tab 1121 at the end of the first electrode 11 and the positive tab 1111 at the end of the second electrode 12 can both extend out of the housing 15, in order to prevent the negative tab 1121 at the end of the first electrode 11 and the positive tab 1111 at the end of the second electrode 12 from conducting with the housing 15 of the battery cell 1, the outside of the negative tab 112 of the first electrode 11 and the positive tab 111 of the second electrode 12 can be covered with a polyester film 14, so that the positive tab 111 of the first electrode 11 and the negative tab 112 of the second electrode 12 are both insulated from the housing 15, thereby further preventing the negative tab 112 of the first electrode 11 and the positive tab 111 of the second electrode 12 from conducting with the housing 15 of the battery cell 1 and causing a short circuit in the battery cell 1.
[0040] In one embodiment, reference Figure 4The battery cell 1 also includes a housing 15. The first electrode 11, the second electrode 12 and the connector 13 are disposed in the housing 15. The housing 15 is provided with an explosion-proof valve 16. The first electrode 11 and the second electrode 12 include a positive end tab 1111 and a negative end tab 1121 located at both ends and not connected to the connector 13. Along the length direction of the first electrode 11 and the second electrode 12, the distance d3 between the positive end tab 1111 and the explosion-proof valve 16 and the distance d1 between the negative end tab 1121 and the explosion-proof valve 16 are both not less than 15mm, that is, d1≥15mm and d3≥15mm. When only one explosion-proof valve 16 is installed on the housing 15, the explosion-proof valve 16 is set at a position away from the edge of the battery cell 1, that is, away from the positive end tab 1111 and the negative end tab 1121, and is set at a position close to the middle of the battery cell 1. This can facilitate the installation of the explosion-proof valve 16 and can also release the pressure of the battery cell 1 in time when a short circuit, overcharge or other danger occurs inside the battery cell 1.
[0041] In one embodiment, reference Figure 1 Multiple explosion-proof valves 16 are provided, and each explosion-proof valve 16 corresponds to at least two pole cores. Along the length direction of the at least two pole cores, the distance between the positive pole tab 111 and the negative pole tab 112 of each explosion-proof valve 16 and the pole core to which it corresponds is not less than 15mm. Taking the battery cell 1, which includes a first electrode 11 and a second electrode 12, and two explosion-proof valves 16, with the two explosion-proof valves 16 corresponding to the first electrode 11 and the second electrode 12 respectively, as an example, taking the explosion-proof valve 16 corresponding to the first electrode 11 as an example, the distance d2 between the positive electrode tab 111 of the first electrode 11 and the explosion-proof valve 16 along the length direction of the first electrode 11 is not less than 15mm, that is, d2≥15mm. The distance d1 between the negative electrode tab 1121 at the end of the first electrode 11 and the explosion-proof valve 16 along the length direction of the first electrode 11 is not less than 15mm, that is, d1≥15mm. The above settings can also facilitate the installation of the explosion-proof valve 16, and at the same time, when the battery cell 1 needs to be depressurized, the explosion-proof valve 16 can depressurize the battery cell 1 in time.
[0042] In one embodiment, the battery cell 1 further includes an electrolytic medium (not shown in the figure), which is configured as a solid-state electrolytic medium. When the first electrode core 11 and the second electrode core 12 are connected in series, the voltage of the battery cell 1 is the sum of the voltages of the first electrode core 11 and the second electrode core 12. Since the solid-state electrolytic medium allows for a higher operating voltage than the operating voltage of the first electrode core 11 and the second electrode core 12 connected in series, the first electrode core 11 and the second electrode core 12 can share the same solid-state electrolytic medium. Furthermore, the solid-state electrolytic medium can also improve the energy density of the battery.
[0043] It should be noted that when using a liquid electrolyte, the allowable operating voltage range of the electrolyte is generally no more than 4.5V, which is less than the sum of the voltages of the first electrode core 11 and the second electrode core 12 connected in series. Therefore, the first electrode core 11 and the second electrode core 12 cannot share the same electrolyte. If liquid electrolyte is required, it must be installed and sealed separately from the first electrode core 11 and the second electrode core 12. Compared to liquid electrolyte, using a solid electrolyte is easier to install, and cell 1 has a higher energy density.
[0044] Furthermore, this application also provides a battery having the cell 1 described in any of the above embodiments, and the battery further includes a casing, with the cell 1 disposed within the casing. Typically, the battery casing has multiple cells 1 arranged in series or parallel.
[0045] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. An electric cell, characterized by, include: At least two electrode cores, each of the at least two electrode cores being provided with a positive electrode tab and a negative electrode tab, and the at least two electrode cores being connected in series along the length direction of the battery cell; A connector is disposed between two adjacent pole pieces, and the positive electrode tab of one pole piece and the negative electrode tab of the other pole piece are welded to the connector.
2. The electric cell of claim 1, wherein, The connector includes an insulating bracket and a conductive plate. The insulating bracket is provided with a mounting hole, and the conductive plate is disposed in the mounting hole. Two opposing surfaces of the conductive plate protrude from the mounting hole, and the two opposing surfaces of the conductive plate are respectively connected to the positive electrode tab of one of the two adjacent electrode cores and the negative electrode tab of the other electrode core.
3. The electric cell of claim 2, wherein, The insulating bracket has grooves on both opposite sides, and the mounting hole is located at the bottom of the grooves to connect the two grooves. The positive and negative tabs connected to the conductive plate are respectively located in the two grooves.
4. The cell of claim 2 or 3, wherein, The battery cell also includes a polyester film, which wraps around the connector and the positive and negative tabs connected to the connector to insulate the conductive plate and the positive and negative tabs connected to the conductive plate from other conductive components within the battery cell.
5. The battery cell according to claim 1, characterized in that, The battery cell also includes a housing, and the at least two electrode cores and the connector are disposed in the housing. The housing is provided with an explosion-proof valve. The at least two electrode cores include a positive end tab and a negative end tab located at both ends and not connected to the connector. Along the length direction of the at least two electrode cores, the distance between the positive end tab, the negative end tab and the explosion-proof valve is greater than or equal to 15 mm.
6. The electric cell of claim 5, wherein, The explosion-proof valve is provided in multiple ways, and each of the multiple explosion-proof valves corresponds one-to-one with the at least two pole cores. Along the length direction of the at least two pole cores, the distance between the positive and negative pole tabs of each explosion-proof valve and the pole core to which the explosion-proof valve corresponds is greater than or equal to 15mm.
7. The electric cell of claim 1, wherein, The battery cell also includes an electrolytic medium, which is configured as a solid electrolytic medium.
8. The electric cell of claim 2, wherein, The battery cell also includes tab adhesive, which is wrapped around the positive tab and the negative tab. The tab adhesive is one of polyimide tape and polyester tape.
9. The electric cell of claim 2, wherein, The insulating support is made of plastic; and / or, The conductive plate is configured as a copper-aluminum composite plate.
10. A battery, characterized by include: shell; The battery cell according to any one of claims 1 to 9, wherein the battery cell is disposed within the housing.