Liquid cooling plate assembly

Abstract

The utility model discloses a liquid cooling plate assembly. The liquid cooling plate assembly comprises a harmonica-shaped tube, a current collector and a nanometer injection molding part, the harmonica-shaped tube comprises a first connecting end, and a plurality of nano micropores are formed in at least one part of the surface of the first connecting end; the current collector comprises a second connecting end, and the second connecting end is connected with the first connecting end; the nano injection molding part is arranged at the joint of the first connecting end and the second connecting end, the nano injection molding part fixedly covers the first connecting end and the second connecting end, and the nano injection molding part fills the nano micropores formed in the first connecting end. The liquid cooling plate assembly is used for improving the fixing and sealing effect between the current collector and the harmonica-shaped tube and reducing the sealing and fixing cost of the current collector and the harmonica-shaped tube.

Description

Technical Field

[0001] The utility model relates to the technical field of battery cooling, in particular to a liquid cooling plate assembly. Background Art

[0002] Existing batteries generate heat when running. In order to avoid the accumulation of heat generated by the battery and affect the battery, the battery needs to be cooled. One existing way to dissipate heat from the battery is to use a liquid cooling plate assembly to cool the battery. The liquid cooling plate assembly generally includes a harmonica tube and a current collector. The harmonica tube is used to absorb the heat generated by the battery, and the harmonica tube will be connected to the current collector. The current collector is used to introduce cooling liquid into the harmonica tube or to extract the cooling liquid after absorbing heat in the harmonica tube. In order to avoid leakage of cooling liquid at the connection between the harmonica tube and the current collector, the connection between the harmonica tube and the connection needs to be sealed and fixed.

[0003] The existing method of sealing and fixing the connection between the current collector and the harmonica tube is welding. The material cost and processing cost required for welding are high. In addition, the yield rate of conventional welding is low. The location where the current collector and the harmonica tube are poorly welded may cause coolant leakage, which will affect the operation of the battery and the cooling effect of the harmonica tube. In addition, the leakage of coolant may also cause thermal runaway of the battery pack, resulting in a relatively serious safety hazard. Utility Model Content

[0004] The utility model aims to provide a liquid cooling plate assembly, which is used to improve the fixing and sealing effect between the current collector and the harmonica tube, and reduce the sealing and fixing cost of the current collector and the harmonica tube.

[0005] The purpose of the utility model is achieved by the following technical solutions:

[0006] A liquid cooling plate assembly, comprising:

[0007] A harmonica tube, comprising a first connecting end, wherein at least a portion of the surface of the first connecting end is formed with a plurality of nano-micropores;

[0008] A current collector, comprising a second connection end, wherein the second connection end is connected to the first connection end;

[0009] The nano injection molding part is arranged at the connection between the first connection end and the second connection end, the nano injection molding part fixedly covers the first connection end and the second connection end, and the nano injection molding part fills the nano pores formed by the first connection end.

[0010] Preferably, the current collector is a metal current collector, a plurality of nano-pores are formed on at least a portion of the surface of the second connecting end, and the nano-injection molding part fills the nano-pores formed on the second connecting end.

[0011] Preferably, the second connecting end is provided with at least a portion of a liquid supply chamber, a portion of the first connecting end extends into the liquid supply chamber, and a portion of the first connecting end exposed from the liquid supply chamber is formed with the nano-pore.

[0012] Preferably, the current collector includes a second connection portion and a first connection portion fixedly connected to the second connection portion, the second connection portion forms the second connection end, and the first connection portion is provided with a connection port communicating with the outside.

[0013] Preferably, the current collector further comprises a metal part and a plastic part which are connected to each other, the plastic part is adjacent to one end of the harmonica tube to form the second connecting end, and the plastic part and the nano-injection molding part form an integrated structure.

[0014] Preferably, a plurality of nano-pores are formed at one end of the metal part connected to the plastic part, and the plastic part fills the nano-pores formed by the metal part and is fixedly connected to the metal part.

[0015] Preferably, the metal part includes a first connecting part, and the first connecting part is provided with a connecting port communicating with the outside.

[0016] Preferably, the current collector is a plastic current collector, and the portion of the current collector covering the first connecting end forms the second connecting end; the nano-injection molding part and the current collector form an integrated structure.

[0017] Preferably, the opposite ends of the harmonica tube are respectively provided with first connecting ends, a pair of the current collectors are provided, a pair of the current collectors are connected to a pair of the first connecting ends in a one-to-one correspondence, and at least one of the current collectors is connected to at least one of the first connecting ends through the nano injection molding part.

[0018] Preferably, the pair of current collectors are of the same or different types, and the type of the current collector is one of a metal current collector, a plastic current collector, or a combination current collector having a metal part and a plastic part.

[0019] Compared with the prior art, the beneficial effects of the utility model include at least:

[0020] By using a nano-injection molding part to connect the first connecting end and the second connecting end, the sealing and fixing of the harmonica tube and the current collector can be achieved, which can effectively improve the sealing effect between the harmonica tube and the current collector; and, the material cost and manufacturing cost of the nano-injection molding part are lower than the material cost and manufacturing cost of welding, which can effectively reduce the sealing and fixing cost of the current collector and the harmonica tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a liquid cooling plate assembly according to an embodiment of the utility model;

[0022] Figure 2 It is a structural schematic diagram of a liquid cooling plate assembly according to another embodiment of the utility model;

[0023] Figure 3 It is a partial cross-sectional view of a liquid cooling plate assembly when a metal current collector is used in an embodiment of the utility model;

[0024] Figure 4 It is a partial cross-sectional view of a liquid cooling plate assembly when a metal current collector is used in another embodiment of the utility model;

[0025] Figure 5 It is a partial cross-sectional view of a liquid cooling plate assembly when a plastic current collector is used in an embodiment of the utility model;

[0026] Figure 6 It is a partial cross-sectional view of a liquid cooling plate assembly when a plastic current collector is used in another embodiment of the utility model;

[0027] Figure 7 It is a partial cross-sectional view of a liquid cooling plate assembly when a combined current collector is used in an embodiment of the utility model;

[0028] Figure 8 It is a partial cross-sectional view of a liquid cooling plate assembly when a combined current collector is used in another embodiment of the utility model.

[0029] In the figure: 1. harmonica tube; 11. first connecting end; 12. flow chamber; 2. current collector; 21. second connecting end; 22. second connecting part; 221. liquid supply chamber; 23. first connecting part; 231. connecting port; 24. metal part; 25. plastic part; 3. nano injection molding part. DETAILED DESCRIPTION

[0030] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete and to fully convey the concepts of example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0031] The words expressing positions and directions described in the present utility model are all explained by taking the drawings as examples, but they can be changed as needed, and all the changes are included in the protection scope of the present utility model.

[0032] like Figure 1 and Figure 2 As shown, the utility model provides a liquid cooling plate assembly, including a harmonica tube 1, a current collector 2 and a nano injection molding part 3.

[0033] Reference Figure 3 , the harmonica tube 1 is provided with a flow cavity 12 for cooling liquid to flow. At least one end of the flow cavity 12 passes through the harmonica tube 1, and the end of the flow cavity 12 passing through the harmonica tube 1 can be used to receive or output cooling liquid. Preferably, both opposite ends of the flow cavity 12 pass through the harmonica tube 1, and the opposite ends of the flow cavity 12 can be used to receive or output cooling liquid, for example, cooling liquid can flow in from one end of the flow cavity 12 and flow out from the other end of the flow cavity 12. The harmonica tube 1 can be arranged near a battery that needs to be cooled or abut against a battery that needs to be cooled, and the cooling liquid in the harmonica tube 1 can be used to absorb the heat of the battery to achieve cooling of the battery. Among them, the harmonica tube 1 is made of a material with good thermal conductivity, for example, the harmonica tube 1 is made of an aluminum alloy material. The harmonica tube 1 can be a thin hollow plate-like structure.

[0034] The harmonica tube 1 includes a first connection end 11. The first connection end 11 is used to connect to the current collector 2 to receive or output cooling liquid. The first connection end 11 can be an end of the harmonica tube 1 penetrated by the flow cavity 12, and the first connection end 11 can be set to one or more. For example, when only one end of the flow cavity 12 penetrates the harmonica tube 1, the first connection end 11 can be set to one; when both opposite ends of the flow cavity 12 penetrate the harmonica tube 1, the first connection end 11 can be positioned as two, and the two first connection ends 11 correspond to the opposite ends of the harmonica tube 1 penetrated by the flow cavity 12. Among them, a plurality of nanopores can be formed on at least a portion of the surface of the first connection end 11. The nanopores can be tiny holes with a pore size between tens and hundreds of nanometers, for example, tiny holes between 10-300μm.

[0035] The current collector 2 is connected to the harmonica tube 1 and is used to input cooling liquid into the harmonica tube 1 or receive cooling liquid flowing out of the harmonica tube 1. The current collector 2 may include a second connecting portion 22 and a first connecting portion 23 fixedly connected to the second connecting portion 22. In some specific embodiments, such as Figure 2 As shown, the axial direction of the first connecting portion 23 may be perpendicular to the thickness direction of the second connecting portion 22. In some specific embodiments, such as Figure 1 As shown, the axial direction of the first connection portion 23 may be parallel to the thickness direction of the second connection portion 22 .

[0036] The first connection part 23 is formed with a connection port 231 communicating with the outside, and the second connection part 22 is formed with a liquid supply chamber 221 for communicating with the flow chamber 12 of the harmonica tube 1. The interior of the current collector 2 is hollow, and the connection port 231 can be connected with the liquid supply chamber 221. Among them, the connection port 231 can be connected with the pipeline for the flow of cooling liquid in the outside to receive the cooling liquid in the outside pipeline or output the cooling liquid to the outside pipeline. When the cooling liquid is connected to the harmonica tube 1, the cooling liquid flows into the current collector 2 from the connection port 231, and flows into the flow chamber 12 of the harmonica tube 1 from the liquid supply chamber 221 of the current collector 2 to absorb the heat emitted by the battery; when the cooling liquid is output from the harmonica tube 1, the cooling liquid after absorbing heat flows from the harmonica tube 1 into the liquid supply chamber 221 of the current collector 2, and flows from the connection port 231 of the current collector 2 to the outside pipeline, so that the cooling liquid is discharged from the liquid cooling plate assembly.

[0037] The current collector 2 may be provided with a second connection end 21. The second connection end 21 is connected to the first connection end 11 to achieve the connection between the current collector 2 and the harmonica tube 1. In addition, the number of current collectors 2 may be set to one or more, and each current collector 2 is formed with a second connection end 21. When the first connection end 11 of the harmonica tube 1 is set to one, the current collector 2 may be set to one and connected to the first connection end 11; when the first connection end 11 of the harmonica tube 1 is set to multiple, the current collector 2 may be set to multiple, and the number of multiple current collectors 2 and multiple first connection ends 11 may be the same, and they may be connected one-to-one.

[0038] The second connection end 21 can be formed at the second connection portion 22 of the current collector 2, so the second connection end 21 has at least a portion of the liquid supply chamber 221. The first connection end 11 can extend into the liquid supply chamber 221 located at the second connection end 21, and a portion of the first connection end 11 exposed from the liquid supply chamber 221 forms a plurality of nano-pores. It should be noted that the nano-pores provided at the first connection end 11 can all be located at the portion of the first connection end 11 exposed from the liquid supply chamber 221; or, a portion of the nano-pores provided at the first connection end 11 is located at the portion of the first connection end 11 exposed from the liquid supply chamber 221, and another portion of the nano-pores is located at the portion of the first connection end 11 extending into the liquid supply chamber 221.

[0039] The nano-injection molding part 3 is disposed at the connection between the first connection end 11 and the second connection end 21, and the nano-injection molding part 3 can fixedly cover the first connection end 11 and the second connection end 21, so that the first connection end 11 and the second connection end 21 are sealed and fixedly connected. When the nano-injection molding part 3 covers the first connection end 11, the nano-injection molding part 3 can fill the nano-micropores formed by the first connection end 11 to enhance the bonding force between the nano-injection molding part 3 and the first connection end 11, enhance the connection stability between the nano-injection molding part 3 and the first connection end 11, and improve the sealing and fixing effect of the nano-injection molding part 3.

[0040] It should be noted that the specific structures and shapes of the above-mentioned harmonica tube 1 and current collector 2 are only some feasible structures and shapes of the harmonica tube 1 and current collector 2 selected for the convenience of explanation. The harmonica tube 1 and current collector 2 in the present application are not limited to the above-mentioned structures and shapes. The first connecting end 11 can also be formed by using a harmonica tube 1 with other structures and shapes, and the second connecting end 21 can be formed by using a current collector 2 with other structures and shapes. Then, a nano-injection molding part 3 is provided at the connection between the first connecting end 11 and the second connecting end 21, so as to realize the sealed and fixed connection of the harmonica tube 1 with other structures and shapes and the current collector 2 with other structures.

[0041] The nano injection molding part 3 can be formed at the connection between the first connection end 11 and the second connection end 21 in the form of nano injection molding. The material of the nano injection molding part 3 can be one or more of PPS plastic, LCP plastic, PEEK plastic, PBT plastic, and PI plastic. When the harmonica tube 1 is provided with only one first connection end 11, the first connection end 11 is sealed and fixedly connected to the second connection end 21 through the nano injection molding part 3; when the harmonica tube 1 is provided with two first connection ends 11, only one first connection end 11 can be sealed and fixedly connected to the second connection end 21 through the nano injection molding part 3, and the other first connection end 11 can be connected to the second connection end 21 in other sealing and fixing ways, for example, by welding to seal and fix the second connection end 21; preferably, when the harmonica tube 1 is provided with two first connection ends 11, the two first connection ends 11 are sealed and fixedly connected to the corresponding second connection end 21 through a nano injection molding part 3 respectively.

[0042] By using the nano injection molding part 3 to perform injection molding at the connection between the first connection end 11 and the second connection end 21, the sealing between the first connection end 11 and the second connection end 21 can be effectively improved. The nano injection molding process has excellent sealing performance, and the material strength of the formed nano injection molding part 3 is relatively high, which can form an excellent sealing and fixing effect between the first connection end 11 and the second connection end 21, thereby achieving a better sealing and fixing between the current collector 2 and the harmonica tube 1, and improving the yield of the liquid cooling plate assembly. In addition, the cost of the nano injection molding process is lower than that of the welding process, which can reduce the sealing and fixing cost of the current collector 2 and the harmonica tube 1.

[0043] Reference Figure 3 and Figure 4In some specific embodiments, the current collector 2 may be a metal current collector, for example, the current collector 2 is a current collector 2 made of aluminum alloy. In order to improve the connection effect between the second connection end 21 of the current collector 2 and the nano-injection molding part 3, a plurality of nano-micropores may be formed on at least a portion of the surface of the second connection end 21. The nano-injection molding part 3 may fill the nano-micropores formed by the second connection end 21 to enhance the bonding force between the nano-injection molding part 3 and the second connection end 21, enhance the connection stability between the nano-injection molding part 3 and the second connection end 21, and improve the sealing and fixing effect of the nano-injection molding part 3.

[0044] When the current collector 2 needs to be connected to the harmonica tube 1, the surface of the harmonica tube 1 and the current collector 2 can be treated first, so that a plurality of nanopores are formed on the surface of the first connection end 11 of the harmonica tube 1, and a plurality of nanopores are formed on the surface of the second connection end 21 of the current collector 2. The first connection end 11 of the harmonica tube 1 is inserted into the second connection end 21 of the current collector 2, and then the connected harmonica tube 1 and the current collector 2 are buried in a prefabricated injection mold for nano injection molding to form a nano injection molding portion 3 at the connection between the first connection end 11 and the second connection end 21. Among them, a cavity adapted to the size and shape of the liquid cooling plate assembly is formed in the injection mold. Therefore, when the connected harmonica tube 1 and the current collector 2 are placed in the pre-formed cavity of the injection mold, the harmonica tube 1 and the current collector 2 occupy part of the cavity, while the part of the space corresponding to the cavity and the nano injection molding part 3 in the injection mold is not occupied. Therefore, when nano injection molding is performed, after the liquid plastic fluid flows into the cavity of the injection mold, it will fill the part of the space corresponding to the cavity and the nano injection molding part 3. After the plastic fluid is cooled, the nano injection molding part 3 is formed. The nano injection molding part 3 is fixedly attached to the current collector 2 and the harmonica tube 1, and fills the nano pores on the second connecting end 21 of the current collector 2 and the first connecting end 11 of the harmonica tube 1, and seals and fixes the current collector 2 and the harmonica tube 1.

[0045] Reference Figure 5 and Figure 6In some other specific embodiments, the current collector 2 may be a plastic current collector. For example, the current collector 2 and the nano-injection molding part 3 may be integrally formed by nano-injection molding, and the portion of the current collector 2 covering the first connection end 11 forms the second connection end 21. Specifically, when the current collector 2 needs to be connected to the harmonica tube 1, the harmonica tube 1 may be surface treated first, so that a plurality of nano-micropores are formed on the surface of the first connection end 11 of the harmonica tube 1. Then, the harmonica tube 1 is placed into the prefabricated injection mold, and the harmonica tube 1 occupies part of the cavity in the injection mold, while the part of the cavity in the injection mold corresponding to the current collector 2 and the nano injection molding part 3 is not occupied. During nano injection molding, the plastic fluid will fill the part of the cavity corresponding to the current collector 2 and the nano injection molding part 3, and after the plastic fluid is cooled, an integrated plastic current collector and nano injection molding part 3 are formed, and the second connecting end 21 of the nano injection molding part 3 and the current collector 2 is fixedly attached to the first connecting end 11 of the harmonica tube 1, and the nano injection molding part 3 fills the nano pores on the first connecting end 11, so that the current collector 2 and the harmonica tube 1 are sealed and fixedly connected.

[0046] Reference Figure 7 and Figure 8 In other specific embodiments, the current collector 2 can be a combined current collector having a metal part 24 and a plastic part 25. The plastic part 25 forms a second connection end 21 at one end adjacent to the harmonica tube 1, and the plastic part 25 can be integrally formed with the nano injection molding part 3. The metal part 24 is connected to the plastic part 25, and the metal part 24 can be made of aluminum alloy. The metal part 24 can include a first connection part 23 and form a connection port 231 that communicates with the outside. In order to improve the bonding force between the metal part 24 and the plastic part 25, a plurality of nanopores can be formed on the surface of one end where the metal part 24 and the plastic part 25 are connected, the plastic part 25 can be formed by nano injection molding, and the plastic part 25 can fill the nanopores formed on the metal part 24. Among them, the metal part 24 and the plastic part 25 together constitute the current collector 2, and the connection position of the metal part 24 and the plastic part 25 can be selected at different positions of the current collector 2 as needed. Specifically, the connection position of the metal part 24 and the plastic part 25 is located at a position where a step structure is formed in the current collector 2; for example, the connection position of the second connection part 22 and the first connection part 23 in the current collector 2 forms a step structure, the second connection part 22 forms the plastic part 25, and the first connection part 23 forms the metal part 24. Alternatively, the connection position of the metal part 24 and the plastic part 25 can be formed on the second connection part 22, a part of the second connection part 22 forms the metal part 24 with the first connection part 23, and another part of the second connection part 22 forms the plastic part 25. Alternatively, the connection position of the metal part 24 and the plastic part 25 can be formed on the first connection part 23, a part of the first connection part 23 forms the plastic part 25 with the first connection part 23, and another part of the first connection part 23 forms the metal part 24.

[0047] When the current collector 2 needs to be connected to the harmonica tube 1, the metal part 24 and the harmonica tube 1 can be surface treated first, so that the end of the metal part 24 used for connecting with the plastic part 25 forms nanopores, and the first connecting end 11 of the harmonica tube 1 forms nanopores. The metal part 24 and the harmonica tube 1 are placed in a prefabricated injection mold, the harmonica tube 1 and the metal part 24 occupy part of the cavity in the injection mold, and the part of the cavity in the injection mold corresponding to the plastic part 25 and the nano injection molding part 3 is not occupied. When nano injection molding is performed, the plastic fluid will fill the part of the cavity corresponding to the plastic part 25 and the nano injection molding part 3, and after the plastic fluid is cooled, an integrated plastic part 25 and nano injection molding part 3 are formed. The plastic part 25 is fixedly attached to the metal part 24 and fills the nanopores on the metal part 24 to achieve a sealed and fixed connection between the plastic part 25 and the metal part 24; the nano injection molding part 3 is fixedly attached to the first connecting end 11 and fills the nanopores on the first connecting end 11 to achieve a sealed and fixed connection between the plastic part 25 integrally connected to the nano injection molding part 3 and the harmonica tube 1.

[0048] In some specific embodiments, when the first connecting ends 11 are provided at both opposite ends of the harmonica tube 1, the harmonica tube 1 and a pair of current collectors 2, the pair of current collectors 2 can use the same type of current collectors 2, for example, the pair of current collectors 2 are metal current collectors, plastic current collectors, or combined current collectors; or, the pair of current collectors 2 can be different types of current collectors 2, for example, one current collector 2 is a metal current collector, and the other current collector 2 is a plastic current collector; or, one current collector 2 is a metal current collector, and the other current collector 2 is a combined current collector; or, one current collector 2 is a combined current collector, and the other current collector 2 is a plastic current collector.

[0049] Although the embodiments of the utility model have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the utility model. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the utility model without departing from the principles and purpose of the utility model. All of these changes should fall within the scope of protection of the claims of the utility model.

Claims

1. A liquid cooling plate assembly, characterized in that: include: A harmonica tube (1) comprises a first connecting end (11), wherein at least a portion of the surface of the first connecting end (11) is formed with a plurality of nano-micropores; A current collector (2), comprising a second connection end (21), wherein the second connection end (21) is connected to the first connection end (11); The nano-injection molding part (3) is arranged at the connection between the first connection end (11) and the second connection end (21); the nano-injection molding part (3) fixedly covers the first connection end (11) and the second connection end (21); and the nano-injection molding part (3) fills the nano-pores formed by the first connection end (11).

2. The liquid cooling plate assembly according to claim 1, characterized in that: The current collector (2) is a metal current collector, a plurality of nano-pores are formed on at least a portion of the surface of the second connection end (21), and the nano-injection molding part (3) fills the nano-pores formed by the second connection end (21).

3. The liquid cooling plate assembly according to claim 2, characterized in that: The second connecting end (21) is provided with at least a portion of a liquid supply chamber (221), a portion of the first connecting end (11) extends into the liquid supply chamber (221), and the portion of the first connecting end (11) exposed from the liquid supply chamber (221) is formed with the nano-pore.

4. The liquid cooling plate assembly according to claim 2, characterized in that: The current collector (2) comprises a second connecting portion (22) and a first connecting portion (23) fixedly connected to the second connecting portion (22), the second connecting portion (22) forming the second connecting end (21), and the first connecting portion (23) being provided with a connecting port (231) communicating with the outside.

5. The liquid cooling plate assembly according to claim 1, characterized in that: The current collector (2) further comprises a metal part (24) and a plastic part (25) which are connected to each other, wherein the plastic part (25) is adjacent to one end of the harmonica tube (1) to form the second connection end (21), and the plastic part (25) forms an integrated structure with the nano-injection molding part (3).

6. The liquid cooling plate assembly according to claim 5, characterized in that: A plurality of nano-micropores are formed at one end of the metal part (24) connected to the plastic part (25); the plastic part (25) fills the nano-micropores formed by the metal part (24) and is fixedly connected to the metal part (24).

7. The liquid cooling plate assembly according to claim 5, characterized in that: The metal part (24) comprises a first connecting part (23), wherein the first connecting part (23) is provided with a connecting port (231) communicating with the outside.

8. The liquid cooling plate assembly according to claim 1, characterized in that: The current collector (2) is a plastic current collector, and the portion of the current collector (2) covering the first connection end (11) forms the second connection end (21); the nano-injection molding part (3) and the current collector (2) form an integrated structure.

9. The liquid cooling plate assembly according to claim 1, characterized in that: The first connecting ends (11) are respectively provided at opposite ends of the harmonica tube (1), a pair of the current collectors (2) are provided, a pair of the current collectors (2) are connected to a pair of the first connecting ends (11) in a one-to-one correspondence, and at least one of the current collectors (2) is connected to at least one of the first connecting ends (11) via the nano-injection molding part (3).

10. The liquid cooling plate assembly according to claim 9, characterized in that: The pair of current collectors (2) are of the same or different types, and the type of the current collectors (2) is one of a metal current collector, a plastic current collector, or a combination current collector having a metal part (24) and a plastic part (25).

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