Battery cell assembly, battery and electric equipment

Abstract

The utility model relates to the field of batteries, and discloses a battery cell assembly, a battery and electric equipment, the battery cell assembly comprises a plurality of battery cell monomers arranged along a first direction, each battery cell monomer is provided with a battery cell pole, and the corresponding battery cell poles of two adjacent battery cell monomers are connected through an adapter piece. A concave area is arranged on the inner side surface, facing the battery cell single body, of the adapter plate, a gap is formed between the concave area and the battery cell pole, and the gap is filled with a heat-conducting medium. According to the utility model, the concave area is arranged on the connecting surface of the switching piece and the battery cell pole column, so that the concave area is filled with the heat-conducting medium, the battery cell pole column and the switching piece are well attached, the heat dissipation of the battery is facilitated, the temperature of the battery cell during large-current charging is reduced, and the reliability and the safety of the battery cell under the condition of over 6C fast charging are ensured.

Description

Technical Field

[0001] This application belongs to the field of batteries, and particularly relates to a battery cell assembly, a battery, and an electrical device using the same. Background Art

[0002] During the charging process of power batteries, heat is generated, especially in the case of high-power fast charging. The greater the current passing through the battery cells, the more heat is generated and the higher the temperature. Currently, in order to solve the charging time problem for power batteries using square shell battery cells, the fast charging current of the battery has been increased to over 600A. To meet the charging requirements of the battery cells and ensure the safety of the battery, it is urgent to improve the cooling capacity of the battery.

[0003] To precisely cool the high-temperature areas of the battery cells, there are currently some design solutions. By directly cooling the electrical connection bars between the battery cells through a cooling component, and then taking away the heat generated by components such as the battery cell terminals and electrical connection plates. However, currently, the electrical connection plates and the battery cell terminals are often connected by a laser welding process in the form of dots / strips / arcs or closed loops. Since the laser welding process can achieve welding even when there is a weld seam of about 0.2 mm between the battery cell terminals and the electrical connection plates, there may be a problem of an air layer of less than 0.2 mm in other areas between the battery cell terminals and the electrical connection plates except for the weld seam itself, which in turn affects the heat transfer from the terminal to the electrical connection plate. Summary of the Utility Model

[0004] The purpose of this application is to provide a battery cell assembly, a battery, and an electrical device using the same, which can improve the heat transfer between the battery cell terminals and the adapter plates, thereby helping the battery achieve better heat dissipation and improving the life and safety of the battery.

[0005] To achieve the above purpose, on the one hand, this application provides a battery cell assembly. The battery cell assembly includes a plurality of battery cell monomers arranged along a first direction. Each of the battery cell monomers has a battery cell terminal. The corresponding battery cell terminals of the battery cell monomers to be connected are connected by an adapter plate. A recessed area is provided on the inner side surface of the adapter plate facing the battery cell monomer. A gap is formed between the recessed area and the battery cell terminal, and the gap is filled with a heat-conducting medium. By adopting the above technical solution, a recessed area is formed on the inner side surface of the adapter plate facing the battery cell terminal to fill the heat-conducting medium therein, so that the battery cell terminal and the adapter plate are in good contact, which is beneficial to the heat dissipation of the battery. Moreover, the heat dissipation effect during charging is improved through the heat-conducting medium, and the life and safety of the battery are improved.

[0006] In some embodiments, the thickness of the recessed area is h, and the thickness of other areas of the adapter plate is H. The value of h / H is 0.05 - 0.95. With this structure, the closer the value of h / H is to 0.95, the better the heat dissipation effect.

[0007] In some embodiments, the inner side area of the adapter piece is S, the total area of all the recessed areas on the adapter piece is s-thin, and the value of s-thin / S is 0.1 - 0.9. With this structure, the closer the value of s-thin / S is to 0.9, the better the heat dissipation effect.

[0008] In some embodiments, the adapter piece includes a first connection part and a second connection part, which are connected by a transition part. Among them, the first connection part and the second connection part are respectively connected to the cell poles of the corresponding cell unit, and the recessed areas are respectively provided on the inner side surfaces of the first connection part and the second connection part.

[0009] In some embodiments, riveting posts are formed on the end surfaces of the cell poles. The recessed area covers the end surface of the cell pole, and a hole is formed in the recessed area, and the hole is directly opposite to the corresponding riveting post. With this structure, through the hole, it is possible to observe whether the adapter piece and the cell pole are aligned, and at the same time, it is convenient to pour the heat-conducting medium.

[0010] In some embodiments, the diameter of the hole is 1 - 10 mm. With this structure, generally speaking, the smaller the diameter of the hole, the more space can be saved for the heat-conducting medium, and the better the improvement effect on heat dissipation.

[0011] In some embodiments, each cell unit has at least one positive pole and at least one negative pole, and the recessed areas are respectively formed at the positions where the adapter piece is connected to the corresponding positive pole and / or negative pole. With this structure, the positive and negative polarities of connecting two cell poles can be selected as needed.

[0012] In some embodiments, the heat-conducting medium is a non-metallic heat-conducting medium, and its heat-conductivity coefficient is 0.1 - 20 W / m·K. The heat-conducting medium can be a heat-conducting gasket, heat-conducting glue, double-sided tape, heat-conducting silicone grease, heat-conducting liquid, etc.

[0013] The second aspect of the present application provides a battery, which includes the cell assembly provided in the first aspect of the present application.

[0014] The third aspect of the present application provides an electrical device, which includes the battery provided in the second aspect of the present application.

[0015] Through the above technical solutions, by providing recessed areas on the connection surfaces of the adapter piece and the cell poles, so as to fill the heat-conducting medium therein, thereby enabling good adhesion between the cell poles and the adapter piece, which is beneficial to battery heat dissipation, reduces the temperature of the cell during high-current charging, and ensures the reliability and safety of the cell under fast charging of 6C or more.

[0016] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific embodiment part. Brief Description of the Drawings

[0017] The drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation to the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings. In the drawings:

[0018] Figure 1 It is a schematic diagram of a battery cell assembly;

[0019] Figure 2 It is a partial structural cross-sectional view of a connecting piece and a battery cell terminal;

[0020] Figure 3 It is a schematic diagram of the structure of the connecting piece;

[0021] Figure 4 It is a schematic diagram of a double-layer structure formed by a connecting piece and a reinforcing piece;

[0022] Figure 5 It is a schematic diagram of the structure of a battery cell.

[0023] Description of the Reference Numerals in the Drawings

[0024] 1 Battery cell 111 Battery cell housing

[0025] 112 Battery cell top cover 113 Battery cell explosion-proof valve

[0026] 2 Battery cell terminal 3 Connecting piece

[0027] 3a First connecting portion 3b Second connecting portion

[0028] 3c Transition portion 4 Concave area

[0029] 5 Heat-conducting medium 6 Riveting post

[0030] 7 Hole Detailed Description of the Embodiments

[0031] The following provides a detailed description of the specific embodiments of the present application in conjunction with the drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0032] The following is described with reference to the drawings.

[0033] As Figure 1 shown, in the present application, the first direction refers to the thickness direction of the battery cell, the second direction refers to the height direction of the battery cell, and the third direction refers to the length direction of the battery cell.

[0034] As Figure 1 and 2 shown, the present application provides a battery cell assembly, which includes a plurality of battery cell monomers 1 arranged in a first direction. Each of the battery cell monomers 1 has a battery cell pole 2. The corresponding battery cell poles 2 of the battery cell monomers 1 to be connected are connected by a transfer piece 3. A recessed area 4 is provided on the inner side surface of the transfer piece 3 facing the battery cell monomer 1. A gap is formed between the recessed area 4 and the battery cell pole 2, and a heat-conducting medium 5 is filled in the gap.

[0035] The battery cell monomers 1 connected by the transfer piece 3 can be two, or three or more. The battery cell monomers 1 can be arranged adjacent to each other in sequence, and in some embodiments, they can also be arranged in other ways.

[0036] A recessed area 4 is provided on the transfer piece 3, thereby dividing the transfer piece 3 into the recessed area 4 and other areas. The formation of the recessed area 4 can be achieved by thinning the transfer piece 3 to form a recessed part. At this time, the thickness of the recessed area 4 is less than that of other areas. The recessed area 4 can also be formed by the depression of a part of the area of the transfer piece 3. At this time, the thickness of the recessed area 4 is equal to that of other areas.

[0037] In some embodiments, the heat-conducting medium 5 is a non-metallic heat-conducting medium, and its heat-conductivity coefficient is 0.1-20 W / m·K. Specifically, the heat-conducting medium 5 can be a heat-conducting gasket, heat-conducting glue, double-sided tape, heat-conducting silicone grease, heat-conducting liquid, etc.

[0038] In some embodiments, the battery cell assembly includes at least two battery cell monomers 1. Each of the battery cell monomers 1 has at least one positive pole and at least one negative pole. The transfer piece 3 is respectively formed with the recessed area 4 at the positions connected to the corresponding positive poles and / or negative poles. That is, the two battery cell poles 2 connected by the transfer piece 3 can be a positive pole and a negative pole, or two positive poles, or two negative poles.

[0039] The connection between the transfer piece 3 and the battery cell pole 2 can be welding, screwing, riveting, or bonding with a conductive adhesive. The specific part using this connection between the two is between the other area of the transfer piece 3 and the battery cell pole 2. Welding, screwing, riveting, conductive adhesive bonding, etc. are well-known to those skilled in the art and do not belong to the core improvement part of the present application, so they will not be elaborated here.

[0040] In some embodiments, only one recessed area can be provided on the transfer piece 3, corresponding to one of the battery cell poles 2 to be connected. Two recessed areas can also be provided, corresponding to two battery cell poles 2 respectively. More recessed areas can also be provided, corresponding to the battery cell poles 2 to be connected respectively.

[0041] In some embodiments, the adapter plate 3 may be a single-layer structure as shown in Figure 3 . In some other embodiments, an enhancement layer may be provided on the outer side surface of the adapter plate 3 to form a double-layer structure as shown in Figure 4 . The enhancement layer may be fixed on the outer side surface of the adapter plate 3 by means such as bonding. By adding the layer, the magnitude of the current that can flow through can be further increased.

[0042] In some embodiments, the structure of the single cell 1 is as shown in Figure 5 . It includes a cell housing 111, a cell top cover 112 is sealed on the top of the cell housing 111, a cell pole 2 is provided on the cell top cover 112, a riveting post 6 is formed on the end surface of the cell pole 2, and a cell explosion-proof valve 113 is also provided on the cell top cover 112. The single cell 1 may have one positive pole and one negative pole, or two positive poles and two negative poles, or multiple positive poles and multiple negative poles. The positive and negative poles on the single cell 1 may be on the same surface of the single cell 1 or distributed on different surfaces. The cell pole 2 may be cylindrical or square.

[0043] As shown in Figure 5 , in some embodiments, the dimension of the single cell 1 in the third direction is L3-CELL, the dimension in the first direction is L4-CELL, the dimension of the cell pole 2 in the third direction is L1-CELL, the dimension in the first direction is L2-CELL, and 0.1 ≤ L1-CELL / L3-CELL ≤ 0.4, 0.1 ≤ L2-CELL / L4-ELL ≤ 0.99.

[0044] In some embodiments, the adapter plate 3 includes a first connection portion 3a and a second connection portion 3b, which are connected by a transition portion 3c. Preferably, the first connection portion 3a, the second connection portion 3b, and the transition portion 3c can be integrally formed into an integral structure. The first connection portion 3a and the second connection portion 3b are respectively connected to the cell pole 2 of the corresponding single cell 1, and the concave regions 4 are respectively provided on the inner side surfaces of the first connection portion 3a and the second connection portion 3b. The transition portion 3c can be recessed as a whole towards the inner side surface direction of the adapter plate 3, such as Figure 1 recessed along the gap direction between two adjacent single cells 1, so that the connection structure is more compact and does not occupy space.

[0045] The thickness of the recessed area 4 is h, the thickness of other areas of the adapter piece 3 is H, the value of h / H is 0.05 - 0.95, the inner side area of the adapter piece 3 facing the single cell 1 is S, the total area of all the recessed areas 4 on the adapter piece 3 is s-thin, and the value of s-thin / S is 0.1 - 0.9. Specifically, in this embodiment, the sum of the inner side areas of the first connecting portion 3a, the second connecting portion 3b and the transition portion 3c facing the single cell 1 is S. The recessed areas 4 are respectively arranged on the inner side surfaces of the first connecting portion 3a and the second connecting portion 3b facing the single cell 1, and the total area of all the recessed areas 4 on the first connecting portion 3a and the second connecting portion 3b is s-thin.

[0046] In some embodiments, the recessed area 4 covers the end face of the cell terminal 2, and a hole 7 is formed in the recessed area 4. The hole 7 is directly opposite to the corresponding riveting post 6. The diameter of the hole 7 is 1 - 10 mm. In this embodiment, the recessed areas 4 are respectively arranged on the inner side surfaces of the first connecting portion 3a and the second connecting portion 3b, and the center line of the hole 7 coincides with the center line of the riveting post 6.

[0047] In some embodiments, as Figure 3 shown, the width of the adapter piece 3 is L-BUSBAR, 0.1 ≤ L-BUSBAR / L1-ELL ≤ 0.99, and the thickness of the adapter piece 3 is 1 - 5 mm.

[0048] During production, the first connecting portion 3a and the second connecting portion 3b of the adapter piece 3 are first laser welded, screwed or riveted to the corresponding two cell terminals 2 through other areas, so as to connect the two together. Then, through the hole 7 on the adapter piece 3, the heat-conducting medium 5 is potted into the gap formed between the adapter piece 3 in the recessed area 4 and the cell terminal 2.

[0049] Or, first fill the heat-conducting medium 5 into the recessed area 4 on the adapter piece 3, and then laser weld, screw or rivet the adapter piece 3 and the cell terminal 2 through other areas of the first connecting portion 3a and the second connecting portion 3b, so as to connect the two together.

[0050] In some embodiments, the cell assembly may include 2, 3, 4, 5,... N single cells 1, and the number thereof is selected according to the battery capacity requirement. The provided electrical connection structure of the present application can be used for various requirements such as series connection and parallel connection of single cells. The beneficial effects of the present application are illustrated by specific experimental data below.

[0051] When the sizes of the single battery cells and the adapter plates adopted are as follows: L3-CELL is 208 mm, L4-CELL is 54 mm, L1-CELL is 24 mm, L2-CELL is 32 mm, the H of the adapter plate 3 is 1.5 mm, the thickness of the adapter plate 3 at the recessed area 4 is 1 mm, the proportion of the total area s-thin of the recessed area in the total inner side area S of the adapter plate 3 is 30%, the heat transfer coefficient of the heat transfer medium 5 is 2 W / m·K, the heat transfer power between the battery cell terminal 2 and the adapter plate 3 is 9.84 W, and the 6C fast charging time is 626 s.

[0052] For the single battery cells and adapter plates of the same size, the difference from the electrical connection structure provided by the present application is that: there is no recessed area 4 on the adapter plate 3, and there is no heat transfer medium 5 filled. For this structure, the heat transfer power between the battery cell terminal 2 and the adapter plate 3 is 8.98 W, and the 6C fast charging time is 633 s.

[0053] It can be seen that the structure provided by the present application can significantly improve the heat transfer power between the battery cell terminal and the adapter plate and shorten the 6C fast charging time.

[0054] As Figure 1 shown, the present application also provides a battery, and the battery includes the battery cell assembly provided in the first aspect of the present application.

[0055] In some embodiments, the battery may further include a plurality of single battery cells 1 arranged along the second direction, and / or a plurality of single battery cells 1 arranged along the third direction.

[0056] The present application also provides an electrical device, and the electrical device includes the battery provided by the present application.

[0057] In the description of the present application, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0058] In the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or communication with each other; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal connection of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0059] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0060] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A battery cell assembly, characterized in that: The battery cell assembly includes a plurality of battery cell units arranged along a first direction, each of the battery cell units having a battery cell pole, and the corresponding battery cell poles of the battery cell units to be connected are connected via a transition piece, and a recessed area is provided on the inner side surface of the transition piece facing the battery cell unit, a gap is formed between the recessed area and the battery cell pole, and the gap is filled with a heat conductive medium.

2. The battery cell assembly according to claim 1, characterized in that: The thickness of the recessed area is h, the thickness of the other areas of the adapter sheet is H, and the value of h / H is 0.05-0.

95.

3. The battery core assembly according to claim 1 or 2, characterized in that: The inner surface area of ​​the adapter sheet is S, the total area of ​​all the recessed areas on the adapter sheet is s-thin, and the value of s-thin / S is 0.1-0.

9.

4. The battery cell assembly according to claim 3, characterized in that: The adapter sheet includes a first connection portion and a second connection portion, which are connected by a transition portion, wherein the first connection portion and the second connection portion are respectively connected to the cell poles of the corresponding cell monomers, and the recessed areas are respectively provided on the inner side surfaces of the first connection portion and the second connection portion.

5. The battery core assembly according to claim 1 or 2, characterized in that: A rivet column is formed on the end surface of the battery cell pole, the recessed area is covered on the end surface of the battery cell pole, and a hole is opened in the recessed area, and the hole is directly opposite to the corresponding rivet column.

6. The battery cell assembly according to claim 5, characterized in that: The diameter of the holes is 1-10 mm.

7. The battery cell assembly according to claim 1, characterized in that: Each of the battery cells has at least one positive electrode column and at least one negative electrode column, and the adapter is respectively formed with the recessed areas at the positions where it is connected to the corresponding positive electrode column and / or negative electrode column.

8. The battery core assembly according to claim 1 or 7, characterized in that: The heat-conducting medium is a non-metallic heat-conducting medium, and its thermal conductivity is 0.1-20 W / m·K.

9. A battery, characterized in that: A battery core assembly comprising any one of claims 1 to 8.

10. An electrical device, characterized in that: A battery comprising the battery of claim 9.

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