Battery cell, battery module and battery pack

Abstract

The utility model provides a battery cell, a battery module and a battery pack, the battery cell is provided with two pole posts, a tenon is formed on one pole post, and a mortise matched with the tenon is formed on the other pole post. According to the battery cell disclosed by the utility model, the tenon structures and the mortise structures are arranged on the pole columns, so that the battery cells can be connected in a mortise and tenon manner to form a series relation among the battery cells, and compared with the prior art that a busbar is adopted for connection, the battery cell disclosed by the utility model can reduce the use of the busbar, realize the saving of materials and reduce the production cost. And meanwhile, the total mass of the battery cells after connection can be reduced, the lightweight design is realized, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to an electric core. The utility model also relates to a battery module having the above-mentioned electric core, and a battery pack provided with the battery module. Background Art

[0002] A battery module is a smaller unit that makes up a battery pack. It can encapsulate multiple electric cores within the same outer shell frame and communicate with the outside through a unified boundary, providing a higher voltage and capacity to meet the power requirements of various devices. A battery module usually contains multiple electric cores, and these electric cores are combined in series and parallel to form a unit with an independent power supply function.

[0003] The electrical connection method of the electric cores in the battery module is mainly through busbars. The busbars are usually made of copper or aluminum and are fixed in position by the busbar brackets in the battery module, corresponding to the pole columns of the corresponding electric cores. A relatively common connection method between the busbar and the electric core is: the busbar is welded between two adjacent electric cores to conduct the two electric cores, so as to realize the series or parallel connection between the electric cores. However, this connection method of electric cores requires a large number of busbars during the assembly of the battery module, and the process of assembling and connecting each electric core is cumbersome and inconvenient. Summary of the Utility Model

[0004] In view of this, the utility model aims to propose an electric core to make the assembly and connection of the electric core more convenient.

[0005] To achieve the above object, the technical solution of the utility model is realized as follows:

[0006] An electric core has two pole columns. A tenon is formed on one of the pole columns, and a mortise adapted to the tenon is formed on the other pole column.

[0007] Further, the tenon is in the shape of a dovetail, and the mortise is a dovetail groove.

[0008] Compared with the prior art, the utility model has the following advantages:

[0009] For the electric core of the utility model, by setting the tenon structure and the mortise structure on the pole column, the electric cores can be connected in a mortise and tenon manner to form a series relationship between the electric cores. Compared with the prior art that uses busbars for connection, the utility model can reduce the use of busbars, save materials, and at the same time reduce the total mass of the electric cores after connection, achieve lightweight design, and reduce production costs.

[0010] Secondly, by setting the tenon in the shape of a dovetail and the mortise as a dovetail groove, the connection between the two mortise and tenon pole columns can be made more firm and not easy to loosen.

[0011] Another object of the present utility model is to provide a battery module, which is provided with the above-mentioned battery cells.

[0012] Furthermore, a plurality of the battery cells are connected in series to form a group, and the pole columns of adjacent battery cells in the same group are connected by tenon-mortise joints; there are multiple groups of the battery cells, and the battery cells of each group are stacked in sequence.

[0013] Furthermore, conductive adhesive is filled between the pole columns connected by tenon-mortise joints.

[0014] Furthermore, a first heat insulation layer is interposed between the battery cells of adjacent groups.

[0015] Furthermore, the pole columns are arranged on the same side of the battery cell, the upper and lower layers of the battery cells in the same group are arranged with staggered joints, and the battery cells of each group are aligned along the stacking direction; or,

[0016] The pole columns are respectively arranged on both sides of the battery cell, the battery cells in the same group are connected in sequence along one direction, and the battery cells of each group are horizontally aligned.

[0017] Furthermore, a second heat insulation layer is interposed between adjacent battery cells on the same layer.

[0018] Furthermore, an explosion-proof valve is provided between the two pole columns of the battery cell, and isolation bodies are provided on both sides of each explosion-proof valve. The isolation bodies are filled between the upper and lower layers of the battery cells to form an exhaust passage facing the explosion-proof valve.

[0019] The battery module according to the present utility model can save the use of busbars through the above-mentioned battery cells, realize the lightweight design of the battery module, and reduce the production cost of the battery module at the same time. The battery cells are arranged in groups, and each group of battery cells forms a path by means of tenon-mortise joints, which can make the connection of the battery cells closer and make more full use of the space inside the battery module.

[0020] Secondly, by filling conductive adhesive between the pole columns connected by tenon-mortise joints, the gaps existing due to the tolerance setting between the tenon and the mortise can be filled, so that the connection between the two pole columns is more firm and does not affect conductivity. By interposing a first heat insulation layer between the battery cells of adjacent groups, large-area heat transfer between adjacent groups of battery cells can be prevented. Especially in the extreme case of thermal runaway, it can effectively block the heat conduction between the battery cells of adjacent groups and slow down the heat spread. The pole columns of the battery cells are arranged on the same side, the upper and lower sides of the battery cells in the same group are arranged with staggered joints or connected in sequence along one direction, and the battery cells of each group are aligned, which can make the arrangement of the battery cells more compact and improve the space utilization rate of the battery cells in the battery module.

[0021] Furthermore, a second heat insulation layer is arranged between adjacent battery cells in the same layer, which can play a role in heat insulation between laterally adjacent battery cells in the same layer and can effectively protect the battery cells in the extreme case of thermal runaway. The explosion-proof valve is arranged between two pole columns. After the battery cells are connected, cavities are formed between the two side pole columns and the upper and lower battery cells. Then, an isolator is used to block the pole columns, so that after the battery cells are in thermal runaway, the generated gas can be quickly discharged from the explosion-proof valve through the exhaust channel, and does not contact the pole columns during the discharge process, effectively avoiding the short circuit caused by the ejecta after the thermal runaway of the battery cells contacting the pole columns, thus playing a role in slowing down the thermal spread.

[0022] Another object of the present invention is to provide a battery pack, which is provided with the battery module as described above.

[0023] Further, the battery pack includes a first cold plate and a second cold plate;

[0024] The first cold plate contacts the upper-layer battery cells, and the second cold plate contacts the lower-layer battery cells.

[0025] By arranging the above-mentioned battery module in the battery pack of the present invention, the use of busbars and copper bars between the upper and lower layers of battery cells can be reduced, which can not only reduce the weight of the battery pack, but also reduce the cost, and can also save the layout space in the height direction of the battery pack, improving the utilization rate of the whole pack. The first cold plate and the second cold plate are arranged to be able to cool the upper and lower layers of battery cells respectively, with high cooling efficiency and improving the thermal management ability of the battery pack. Description of the Drawings

[0026] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0027] Figure 1 is a schematic structural diagram of the battery cell according to Embodiment 1 of the present invention;

[0028] Figure 2 is a schematic connection structure diagram of the battery cell according to Embodiment 1 of the present invention;

[0029] Figure 3 is a schematic structural diagram of the battery module according to Embodiment 2 of the present invention;

[0030] Figure 4 is Figure 3 a partial enlarged view of part A in

[0031] Figure 5 is a front view of the battery module according to Embodiment 2 of the present invention;

[0032] Figure 6 is Figure 5 a partial enlarged view of part B in

[0033] Figure 7 an exploded view of the battery pack according to Embodiment 3 of the present utility model.

[0034] Description of reference numerals:

[0035] 1, battery cell;

[0036] 101, terminal; 1011, tenon; 1012, mortise; 102, explosion-proof valve;

[0037] 2, bus bar;

[0038] 3, first heat insulation layer;

[0039] 4, second heat insulation layer;

[0040] 5, separator;

[0041] 6, lower housing;

[0042] 7, first cold plate;

[0043] 8, second cold plate;

[0044] 9, bottom guard plate;

[0045] 10, maintenance access cover;

[0046] a, exhaust passage. Detailed implementation manners

[0047] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0048] In the description of the present utility model, it should be noted that if terms indicating orientation or positional relationship such as "upper", "lower", "inner", "outer", etc. appear, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, if terms such as "first", "second", etc. appear, they are also only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0049] In addition, in the description of the present utility model, unless otherwise clearly defined, the terms "installation", "connection", "connection", and "connector" should be understood in a broad sense. 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, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood in combination with specific situations.

[0050] The present utility model will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0051] Embodiment 1

[0052] This embodiment relates to a battery cell to optimize the structure of the battery cell to make the assembly and connection of the battery cell more convenient.

[0053] In terms of the overall structure, a battery cell in this embodiment has two pole posts. A tenon is formed on one pole post, and a mortise adapted to the tenon is formed on the other pole post.

[0054] With the above settings, for the battery cell in this embodiment, by setting the tenon structure and mortise structure on the pole posts, the battery cells can be connected in a tenon-and-mortise manner to form a series relationship between the battery cells. Compared with the prior art in which a bus bar is used for connecting battery cells, the battery cells in this embodiment can also reduce the use of the bus bar during assembly, achieve material savings, and at the same time can reduce the total mass after the battery cells are connected, realize lightweight design, and reduce production costs.

[0055] Based on the above overall introduction, referring to Figure 1 and Figure 2 As shown, specifically, a tenon 1011 is provided on the positive pole post 101 of the battery cell 1 in this embodiment, and a mortise 1012 is provided on the negative pole post 101. When the positive and negative pole posts 101 of two battery cells 1 are connected in a tenon-and-mortise manner, the series connection of two battery cells 1 can be formed. The series connection of multiple battery cells 1 can also be formed by connecting the positive and negative pole posts 101 of multiple battery cells 1 in a tenon-and-mortise manner. The arrangement and connection of the battery cells 1 can be carried out according to actual needs. An explosion-proof valve 102 is provided on the battery cell 1, and the explosion-proof valve 102 is located between the two pole posts 101 on the battery cell 1.

[0056] The battery cell 1 in this embodiment is a directional battery cell 1. Both pole columns 101 are located at the top end of the battery cell 1, and the distances from the two pole columns 101 to the edge of the adjacent top end of the battery cell 1 are equal. With this arrangement, after multiple battery cells 1 are connected, an alternating up-and-down connection structure will be formed. This connection method is not only convenient for installation, but also can save the use of the bus bar 2 and simplify the assembly process. Of course, it is also possible to arrange the two pole columns 101 on different sides of the battery cell 1. For example, the two pole columns 101 are arranged at two opposite ends of the battery cell 1, so that two battery cells 1 can be connected in a straight line. Another example is to arrange the two pole columns 101 on the side walls of two non-parallel ends of the battery cell 1, so that a corner shape can be formed after the two battery cells 1 are connected to meet the requirements for the battery cell 1 in special cases.

[0057] It should be noted that the connection between the battery cells 1 in this embodiment can also be achieved by using the bus bar 2. During specific implementation, tenons 1011 and mortises 1012 with the same shape and size as those on the pole column 101 of the battery cell 1 are processed on the bus bar 2, and then the bus bar 2 is connected between the pole columns 101 of the two battery cells 1 by means of mortise and tenon, and the series connection of the two battery cells 1 can be formed. This connection method can eliminate the welding operation between the battery cell 1 and the bus bar 2, making the installation of the battery cell 1 more convenient.

[0058] Specifically, the tenon 1011 is in the shape of a dovetail, and the mortise 1012 is a dovetail groove. The dovetail-shaped tenon 1011 is narrow at the root and wide at the end, resembling a dovetail. Due to its special shape, the dovetail-shaped tenon 1011 can enhance the pulling force of the mortise and tenon joint between the pole columns 101. When the tenon 1011 is subjected to a pulling force, it will become tighter and tighter, ensuring the connection strength between the pole columns 101. Of course, the shape of the tenon 1011 can also be "T" shape or circular as long as the tenon 1011 does not come out of the mortise 1012 when the tenon 1011 is pulled.

[0059] The battery cell 1 in this embodiment realizes the conduction between the battery cells 1 without welding the bus bar 2 by respectively arranging the tenon 1011 and the mortise 1012 on the two pole columns 101, reduces the use of the bus bar 2, reduces the cost, and at the same time simplifies the assembly process.

[0060] Embodiment Two

[0061] This embodiment relates to a battery module, and the battery module is provided with the battery cell in Embodiment One.

[0062] By adopting the battery cell of Embodiment One, the battery module can save the use of the bus bar. While realizing the lightweight design of the battery module, it can reduce the production cost of the battery module. Secondly, the connection between the battery cells is also more convenient, simplifying the assembly process of the battery module.

[0063] Based on the above overall introduction, referring to Figures 3 to 6 as shown, specifically, in the battery module of this embodiment, multiple battery cells 1 are connected in series to form a group, and the pole columns 101 of adjacent battery cells 1 in the same group are connected by mortise and tenon joints. There are multiple groups of battery cells 1, and the battery cells 1 of each group are stacked in sequence to form a double-layer battery module. Each group of battery cells 1 is connected in series to form a circuit, and the pole columns 101 of two adjacent battery cells 1 in the same group are connected by mortise and tenon joints. Arranging the battery cells 1 in groups and forming a circuit for each group of battery cells 1 in the way of mortise and tenon joints can make the connection of the battery cells 1 closer and make more full use of the space inside the battery module. Between multiple groups of battery cells 1, either series connection or parallel connection can be adopted, which can be adjusted according to the actual voltage requirements.

[0064] It should be noted that the pole columns 101 can also be respectively arranged on both sides of the battery cell 1. The battery cells 1 in the same group are connected in sequence along one direction, and the battery cells 1 of each group are horizontally aligned. With such an arrangement, the battery cells 1 in the same group are arranged in a straight line group. The difference between the battery module formed by the battery cells 1 arranged on the same side as the pole column 101 is that a single-layer battery module is finally formed. During specific implementation, one of the two ways of arranging the pole columns 101 can be selected for implementation according to the needs of a single-layer module or a double-layer module.

[0065] To enhance the connection strength between the battery cells 1, a conductive adhesive is filled between the pole columns 101 connected by mortise and tenon joints. The conductive adhesive is an adhesive that has certain conductivity after curing or drying. By filling the conductive adhesive between the pole columns 101 connected by mortise and tenon joints, the gaps existing due to the tolerance setting between the tenon head 1011 and the mortise 1012 can be filled, making the connection between the two pole columns 101 more firm and not affecting the conductive requirements between the pole columns 101. The conductive adhesive in this embodiment adopts a silver-based conductive adhesive.

[0066] At the same time, to improve the use safety of the battery module, a first heat insulation layer 3 is clamped between adjacent groups of battery cells 1. In this embodiment, the facing surfaces between adjacent groups of battery cells 1 are the largest side surfaces of the battery cells 1. Clamping the first heat insulation layer 3 between the battery cells 1 in adjacent rows can prevent large-area heat transfer between adjacent groups of battery cells 1. Especially in the extreme case of thermal runaway, it can effectively block the heat conduction between the battery cells 1 in adjacent groups and slow down the heat spread.

[0067] Regarding the material selection of the first heat insulation layer 3, in this embodiment, the first heat insulation layer 3 is an aerogel, which can play the roles of heat insulation and shock-proof buffering. Of course, the first heat insulation layer 3 can also be selected as a heat insulation foam, which can also play the roles of heat insulation and shock-proof buffering between the battery cells 1. The connection method between the first heat insulation layer 3 and the battery cell 1 is double-sided adhesive bonding, which can enhance the overall strength of the battery module.

[0068] Regarding the arrangement of the battery cells 1, the terminal posts 101 on the battery cells 1 in this embodiment are arranged on the same side of the battery cells 1. The upper and lower layers of the battery cells 1 in the same group are arranged with staggered joints, and the battery cells 1 in each group are horizontally aligned. By arranging the terminal posts 101 of the battery cells 1 on the same side, arranging the upper and lower sides of the battery cells 1 in the same group with staggered joints, and aligning the battery cells 1 in each group, the arrangement of the battery cells 1 can be made more compact, improving the space utilization rate of the battery cells 1 in the battery module. Moreover, the gaps between the battery cells 1 can be aligned to form an entire passage.

[0069] To further improve the safety performance of the battery module, a second heat insulation layer 4 is provided between adjacent battery cells 1 in the same layer. Providing the second heat insulation layer 4 between adjacent battery cells 1 in the same layer can play a role in heat insulation between the horizontally adjacent battery cells 1 in the same layer and can effectively protect the battery cells 1 in the extreme case of thermal runaway. In this embodiment, the connection method between the second heat insulation layer 4 and the battery cells 1 is bonding, which is convenient for assembly and has a relatively high connection strength. Since the battery cells 1 in each group are in an aligned relationship and the gaps between the battery cells 1 are facing each other in the stacking direction of the battery cells 1 in each group, the second heat insulation layer 4 is provided as a whole and penetrates through the battery cells 1 in all groups along the stacking direction of the battery cells 1 in each group, and can simultaneously fill the gaps at the same positions in the battery cells 1 in each group. In this way, not only can the assembly process of the battery module be simplified, but also the overall strength of the battery module can be improved.

[0070] Among them, regarding the material selection of the second heat insulation layer 4, in this embodiment, an epoxy resin board is selected to make the second heat insulation layer 4. A hollow microporous structure can be formed inside the epoxy resin material, and this structure helps to reduce heat conduction. Secondly, the thermal conductivity coefficient of the epoxy resin is relatively low, which means that it transfers heat at a relatively slow speed, thus having good heat insulation performance. Of course, it is also possible to use materials such as high-temperature resistant composite boards, polyurethane rigid foam boards, aerogel boards, etc., as long as they have good heat insulation performance and a certain structural strength.

[0071] Regarding the setting method of the explosion-proof valve 102 of the battery module, in this embodiment, an explosion-proof valve 102 is provided between the two terminal posts 101 of the battery cell 1, and isolation bodies 5 are provided on both sides of each explosion-proof valve 102. The isolation bodies 5 are filled between the upper and lower layers of the battery cells 1 to form an exhaust passage a facing the explosion-proof valve 102. By arranging the explosion-proof valve 102 between the two terminal posts 101, after the battery cells 1 are connected, cavities can be formed between the two side terminal posts 101 and the upper and lower battery cells 1. Then, using the isolation bodies 5 to block the terminal posts 101 can enable the gas generated after the battery cells 1 are in thermal runaway to be quickly discharged from the explosion-proof valve 102 through the exhaust passage a after spraying, and the discharged gas does not contact the terminal posts 101 during the discharge process, effectively avoiding the short circuit caused by the ejecta after the thermal runaway of the battery cells 1 contacting the terminal posts 101, thereby playing a role in slowing down the thermal spread.

[0072] Among them, for the material selection of the separator 5, the separator 5 in this embodiment is made of heat-insulating foam, which has good heat-insulating ability and high resilience performance, so that the separator 5 can play a certain buffering role for the battery cell 1.

[0073] As for the connection method between each group of battery cells 1, in this embodiment, a bus bar 2 is connected between each group of battery cells 1 to form a series or parallel relationship between each group of battery cells 1. The bus bar 2 and the battery cell 1 can be connected by welding; or a tenon 1011 and a mortise 1012 can be formed on the bus bar 2, corresponding to the pole 101 of the battery cell 1, and a conductive adhesive is filled between the bus bar 2 and the pole 101 during assembly, which can also stably connect each group of battery cells 1.

[0074] By setting the battery cell 1 in the first embodiment, the battery module of this embodiment can save the use of the bus bar 2, realize the lightweight design of the battery module, and reduce the production cost of the battery module at the same time. At the same time, setting the first heat-insulating layer 3, the second heat-insulating layer 4 and the separator 5 can also improve the use safety of the battery module.

[0075] Embodiment Three

[0076] This embodiment relates to a battery pack, and the battery pack is provided with the battery module in the second embodiment.

[0077] By setting the battery module in the second embodiment, the battery pack of this embodiment can reduce the use of the bus bar and the copper bar between the upper and lower layers of battery cells, which can not only reduce the weight of the battery pack, but also reduce the cost, and can also save the layout space in the height direction of the battery pack and improve the utilization rate of the whole pack.

[0078] Specifically, referring to Figure 7 As shown, the battery pack further includes a lower housing 6, a first cold plate 7, a second cold plate 8, a bottom guard plate 9 and a maintenance cover 10. The bottom guard plate 9 is connected to the bottom end of the lower housing 6 to form a chamber in the lower housing 6. Two groups of battery modules in the second embodiment are arranged horizontally in the front and back in the lower housing 6. The second cold plate 8 is arranged between the bottom guard plate 9 and the battery module, and is adhesively connected to the lower-layer battery cell 1 in the battery module for heating or cooling the lower-layer battery cell 1. The first cold plate 7 is connected to the top of the lower housing 6 and jointly closes the top of the lower housing 6 with the maintenance cover 10. The first cold plate 7 is adhesively connected to the upper-layer battery cell 1 in the battery module for heating or cooling the upper-layer battery cell 1.

[0079] By setting the first cold plate 7 and the second cold plate 8, the upper and lower layers of battery cells 1 can be cooled separately, with high cooling efficiency, and the thermal management ability of the battery pack is improved. Among them, the first cold plate 7 also serves as the upper cover plate of the battery pack, which can protect the battery cell 1 and bear the external force at the top of the battery pack.

[0080] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A battery cell, characterized in that: The battery cell has two poles, one of which is formed with a tenon, and the other of which is formed with a tenon groove matched with the tenon.

2. The battery cell according to claim 1, characterized in that: The tenon is dovetail-shaped, and the tenon groove is a dovetail groove.

3. A battery module, characterized in that: The battery module is provided with the battery cell as claimed in claim 1 or 2.

4. The battery module according to claim 3, characterized in that: A plurality of the battery cells are connected in series to form a group, and the poles of the adjacent battery cells in the same group are connected by mortise and tenon joints; the battery cells are provided in a plurality of groups, and the battery cells in each group are stacked in sequence.

5. The battery module according to claim 4, characterized in that: Conductive glue is filled between the poles connected by mortise and tenon joints.

6. The battery module according to claim 4, characterized in that: A first heat insulation layer is sandwiched between the battery cells of adjacent groups.

7. The battery module according to any one of claims 4 to 6, characterized in that: The poles are arranged on the same side of the battery cells, the battery cells in the same group are arranged in staggered layers, and the battery cells in each group are aligned along the stacking direction; or, The poles are respectively arranged on both sides of the battery cells, the battery cells in the same group are connected in sequence along one direction, and the battery cells in each group are aligned horizontally.

8. The battery module according to claim 7, characterized in that: A second heat insulation layer is sandwiched between the adjacent battery cells in the same layer; and / or, The battery cell is provided with an explosion-proof valve between its two poles, and each explosion-proof valve is provided with an isolating body on both sides. The isolating body is filled between the upper and lower layers of the battery cells to form an exhaust channel facing the explosion-proof valve.

9. A battery pack, characterized in that: The battery pack is provided with a battery module as claimed in any one of claims 3 to 8.

10. The battery pack according to claim 9, characterized in that: The battery pack includes a first cold plate and a second cold plate; The first cold plate contacts the upper battery cells, and the second cold plate contacts the lower battery cells.

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