Heat exchange assembly and battery pack

Abstract

The utility model relates to the technical field of electric energy storage, in particular to a heat exchange assembly and a battery pack, which comprises a heat exchange plate provided with a flowing channel through which a flowing working medium flows; each heat exchange piece comprises a transverse part and a longitudinal part, the transverse parts are used for carrying out heat exchange between the end faces of the battery cells and the heat exchange plates, and the longitudinal parts are fixedly connected to the sides, close to the battery cells, of the transverse parts so as to be inserted between the two rows of battery cells. The heat exchange assembly and the battery pack provided by the utility model can effectively solve the problems that the temperature control efficiency is relatively low and the temperature of the battery cell is not uniform due to the fact that an existing heat exchange structure cannot exchange heat with the end surface and the side surface of the battery cell at the same time.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of electric energy storage, especially relates to a heat exchange assembly and battery pack. BACKGROUND

[0002] In the current battery technology field, the heat dissipation problem of the battery cell has been a key factor restricting its performance improvement. Especially under the background of the increasing popularity of fast charging technology, the traditional battery cell cooling technology is facing more severe challenges.

[0003] The mainstream battery cell form in the current market mainly includes square shell battery cells and cylindrical battery cells. For cylindrical battery cells, the existing cooling scheme is to arrange a wave-shaped heat exchange plate between two rows of cylindrical battery cells, thereby cooling the side surface of the cylindrical battery cell.

[0004] However, the wave-shaped heat exchange plate cannot effectively dissipate heat from the end surface of the cylindrical battery cell (i.e. the pole surface of the battery cell). Especially during the fast charging process, the temperature rise of the pole surface is a problem that cannot be ignored, and the existing heat exchange structure is powerless.

[0005] Therefore, it is necessary to improve the existing heat exchange structure to solve the problem that it cannot simultaneously exchange heat with the end surface and the side surface of the battery cell, resulting in low temperature control efficiency and uneven battery cell temperature.

[0006] The above information disclosed in the background section is only included to enhance the understanding of the background of the present disclosure, and therefore can contain information that is not prior art known to those of ordinary skill in the art at the time of the present disclosure. SUMMARY

[0007] An object of the present utility model is to provide a heat exchange assembly and battery pack, which can effectively solve the problem that the existing heat exchange structure cannot simultaneously exchange heat with the end surface and the side surface of the battery cell, resulting in low temperature control efficiency and uneven battery cell temperature.

[0008] To achieve the above object, the present utility model provides a heat exchange assembly, comprising:

[0009] a heat exchange plate provided with a flow channel for flowing working fluid;

[0010] a plurality of heat exchange pieces, the heat exchange pieces comprising a transverse portion for heat exchange between the end surface of the battery cell and the heat exchange plate, and a longitudinal portion fixed to one side of the transverse portion close to the battery cell for insertion between two rows of battery cells.

[0011] Optionally, the heat exchange piece is internally provided with a phase change heat exchange cavity for containing phase change working fluid.

[0012] Optionally, the phase change heat exchange cavity comprises a transverse cavity in the transverse part, and a longitudinal cavity in the longitudinal part and communicating with the transverse cavity.

[0013] Optionally, the surface of the heat exchange plate close to each transverse part is a straight plane, and the surface of the heat exchange plate away from each transverse part is at least partially convex towards the direction away from each transverse part to form the flow channel.

[0014] Optionally, a flexible heat conduction layer for reducing contact thermal resistance is arranged between the heat exchange plate and each transverse part.

[0015] Optionally, a reinforcing groove is arranged on one side of the transverse part close to the battery cell.

[0016] Optionally, the longitudinal part is a wavy structure matching the side surface of a cylindrical battery cell, or the longitudinal part is a flat plate structure matching the side surface of a square shell battery cell.

[0017] In another aspect, a battery pack is provided, comprising an open structure battery box, a battery module in the battery box, and any of the heat exchange assemblies described above arranged in close heat exchange with the battery module and covering the opening of the battery box.

[0018] Optionally, the battery module comprises a plurality of battery cells and a conductive row electrically connecting the end surfaces of the battery cells.

[0019] A heat conduction pad is arranged between the side of each battery cell and the corresponding longitudinal part of the heat exchange assembly.

[0020] Optionally, the end of the transverse part extends to a position protruding from the corresponding conductive row in a direction away from the longitudinal part to cover the corresponding conductive row.

[0021] The heat exchange assembly and the battery pack have the following beneficial effects:

[0022] The transverse part is located between the end surface of the battery cell and the heat exchange plate, thereby realizing heat exchange between the end surface of the battery cell and the heat exchange plate.

[0023] The longitudinal part is inserted between the two rows of battery cells, so that the side surface of the battery cell can indirectly exchange heat with the heat exchange plate after sequentially passing through the longitudinal part and the transverse part.

[0024] Therefore, the end face and the side face of the battery cell can be cooled simultaneously, and the problem that only one face of the battery cell can be heat-exchanged in the prior art is solved, the temperature control efficiency is improved, and the temperature consistency of the end face and the side face of the battery cell is improved.

[0025] Therefore, the heat exchange assembly and the battery pack can effectively solve the problem that the existing heat exchange structure cannot simultaneously exchange heat with the end face and the side face of the battery cell, and the problems of low temperature control efficiency and uneven temperature of the battery cell. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0027] Figure 1 An explosion schematic diagram of the battery pack provided for the embodiments;

[0028] Figure 2 A cross-sectional schematic diagram of the battery pack provided for the embodiments;

[0029] Figure 3 A cross-sectional schematic diagram of the heat exchange member provided for the embodiments.

[0030] In the drawings:

[0031] 1, battery box;

[0032] 2, battery module; 201, battery cell; 202, conductive bar;

[0033] 3, heat exchange assembly; 301, heat exchange plate; 3011, flow channel; 302, heat exchange member; 3021, transverse part; 3021a, transverse chamber; 3021b, reinforcing groove; 3022, longitudinal part; 3022a, longitudinal chamber; 303, flexible heat conduction layer. DETAILED DESCRIPTION

[0034] In the present application, the term "embodiment" means that the specific features, structures or characteristics described in combination with the embodiments can be included in at least one embodiment of the present application. The term "embodiment" appearing in various positions in the specification does not necessarily refer to the same embodiment, and does not particularly limit the independence or association between other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, each technical feature mentioned in each embodiment can be combined in any way to form a corresponding implementable technical solution.

[0035] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the use of related terms in the present description is merely to describe specific embodiments and is not intended to limit the present application.

[0036] In the description of the present application, the phrase "and / or" is a description of the logical relationship between objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this paper generally represents that the associated objects before and after are a "or" logical relationship.

[0037] In the present application, terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, primary and secondary or order relationship between the entities or operations.

[0038] Without more limitations, in the present application, the "includes", "contains", "has" or other similar expressions used in the sentence are intended to cover non-exclusive inclusion, and these expressions do not exclude the presence of other elements in the process, method or product including the described elements, so that the process, method or product including a series of elements can not only include those limited elements, but also include other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0039] As the same as the understanding in the "Guidelines for Examination", in the present application, the expressions such as "greater than", "less than", "exceed" are understood as not including the number; the expressions such as "above", "below", "within" are understood as including the number. In addition, in the description of the embodiments of the present application, the meaning of "multiple" is more than two (including two), and similar expressions related to "multiple" are also understood in this way, for example, "multiple groups", "multiple times" and the like, unless otherwise explicitly limited.

[0040] In the description of the embodiments of the utility model, the space-related expressions used, such as 'center', 'longitudinal', 'transverse', 'length', 'width', 'thickness', 'upper', 'lower', 'front','rear', 'left', 'right','vertical', 'horizontal', 'perpendicular', 'top', 'bottom', 'inner', 'outer', 'clockwise', 'counterclockwise', 'axial', 'radial', 'circumferential', etc., indicate the orientation or positional relationship shown in the specific embodiments or the drawings, and are only for the convenience of describing the specific embodiments of the utility model or for the reader to understand, and do not indicate or imply that the indicated device or component must have a specific position, a specific orientation, or be constructed or operated in a specific orientation, so it cannot be understood as a limitation on the embodiments of the utility model.

[0041] Unless otherwise explicitly specified or limited, in the description of the embodiments of the utility model, the terms such as'mounting', 'connection', 'connection', 'fixing','setting', etc., should be understood broadly. For example, the 'connection' can be fixed connection, or detachable connection, or integrated setting; it can be mechanical connection, or electrical connection, or communication connection; it can be direct connection, or indirect connection through intermediate medium; it can be the communication inside two elements or the interaction relationship between two elements. For the skilled in the art to which the utility model belongs, the specific meaning of the above terms in the embodiments of the utility model can be understood according to the specific circumstances.

[0042] The utility model provides a kind of heat exchange assembly and battery pack, it is applicable to the electric vehicle power battery system needing efficient heat exchange and accurate temperature control, can effectively solve the problem that the existing heat exchange structure cannot simultaneously heat exchange with the end face and side surface of electric core, leading to lower temperature control efficiency, and the temperature of electric core is not even.

[0043] Referring to Figure 1 And Figure 2 The battery pack provided by the embodiment includes a battery box 1, a battery module 2 located in the battery box 1, and a heat exchange assembly 3 that is attached to the battery module 2 for heat exchange and covers the opening of the battery box 1.

[0044] In the embodiment, the battery module 2 includes a plurality of electric cores 201 with poles arranged at the top end face position, and a conductive row 202 electrically connected to the top end face of each electric core 201.

[0045] The heat exchange assembly 3 includes a heat exchange plate 301 and a plurality of T-shaped heat exchange pieces 302. Specifically, one heat exchange piece 302 is arranged corresponding to each two rows of electric cores 201.

[0046] The heat exchange plate 301 is provided with a flow channel 3011 for the flowing working medium. The heat exchange member 302 includes a transverse portion 3021 for heat exchange between the end face of the battery cell 201 and the heat exchange plate 301, and a longitudinal portion 3022 fixed to the transverse portion 3021 close to one side of the battery cell 201 for insertion between the two rows of battery cells 201.

[0047] Specifically, each transverse portion 3021 close to one side of the heat exchange plate 301 exchanges heat with the heat exchange plate 301. Therefore, the heat at the top end face position of the battery cell 201 is sequentially transmitted to the heat exchange plate 301 through the conductive row 202 and the heat exchange member 302.

[0048] Optionally, between each transverse portion 3021 away from one side of the heat exchange plate 301 and the corresponding conductive row 202, and / or between the side face of each battery cell 201 and the longitudinal portion 3022 of the corresponding heat exchange assembly 3, a heat-conducting pad is arranged.

[0049] The heat-conducting pad can increase the heat exchange area between the battery module 2 and the heat exchange member 302, reduce the heat exchange thermal resistance, and thus improve the heat exchange efficiency.

[0050] Optionally, when the heat-conducting pad is arranged between each transverse portion 3021 away from one side of the heat exchange plate 301 and the corresponding conductive row 202, and between the side face of each battery cell 201 and the longitudinal portion 3022 of the corresponding heat exchange assembly 3, the heat-conducting pads at the two positions can be connected to form an overall inverted L-shaped structure. That is, the entire heat-conducting pad extends from the side face position of the longitudinal portion 3022 to the lower side of the transverse portion 3021 to form an inverted L-shaped structure.

[0051] The heat exchange assembly 3 and the battery pack provided by the embodiment can achieve the following effects when the flowing working medium flows in the flow channel 3011 of the heat exchange plate 301:

[0052] The transverse portion 3021 is located between the end face (i.e. the pole face) of the battery cell 201 and the heat exchange plate 301, thereby achieving heat exchange between the end face of the battery cell 201 and the heat exchange plate 301;

[0053] The longitudinal portion 3022 is inserted between the two rows of battery cells 201, so that the side face of the battery cell 201 can indirectly exchange heat with the heat exchange plate 301 after sequentially passing through the longitudinal portion 3022 and the transverse portion 3021;

[0054] Therefore, the end face and the side face of the battery cell 201 can be cooled at the same time, thereby effectively solving the problem that only a single face of the battery cell 201 can exchange heat in the prior art, improving the overall temperature control efficiency, and improving the consistency of the temperature at the end face and the side face of the battery cell 201.

[0055] Therefore, the heat exchange assembly 3 and the battery pack can effectively solve the problem that the existing heat exchange structure cannot simultaneously exchange heat with the end face and the side face of the battery cell 201, thereby reducing the temperature control efficiency and the temperature unevenness of the battery cell 201.

[0056] Optionally, the heat exchange element 302 is internally provided with a phase change heat exchange cavity for containing a phase change working medium. Figure 3 Specifically, the phase change heat exchange cavity comprises a transverse cavity 3021a in the transverse part 3021 and a longitudinal cavity 3022a in the longitudinal part 3022 and communicating with the transverse cavity 3021a.

[0057] The phase change process of the phase change working medium can absorb or release a large amount of heat, thereby improving the heat exchange efficiency. Figure 2 Specifically, the working process of the phase change working medium is as follows:

[0058] (1) Initial state

[0059] In the phase change heat exchange cavity of the heat exchange assembly 3, the phase change working medium (such as water or a specially designed phase change material) is in a liquid state. The flow channel 3011 on the heat exchange plate 301 allows another working medium (such as cooling liquid) to flow through to take away or supply heat.

[0060] (2) Heat absorption and vaporization process (the battery cell 201 generates heat)

[0061] The battery cell 201 generates heat: when the battery cell 201 in the battery pack generates heat during the discharging or charging process, the heat is transferred to the phase change working medium through the heat exchange element 302.

[0062] Phase change working medium vaporization: the phase change working medium absorbs heat and starts to vaporize. During the vaporization process, the temperature of the phase change working medium remains constant until all the liquid is converted into gas. During this process, the phase change working medium absorbs a large amount of latent heat, effectively reducing the temperature of the battery cell 201;

[0063] (3) Phase change heat release process

[0064] Phase change working medium condensation: the vaporized phase change working medium (gas state) moves upward and enters the transverse cavity 3021a to transfer heat to the heat exchange plate 301 through the transverse part 3021, and the heat exchange plate 301 further transfers the heat to the working medium (such as cooling liquid) in the flow channel 3011.

[0065] (4) Working medium backfall cycle

[0066] The condensed phase change working medium after heat release is in a liquid state and automatically backfalls to the lower longitudinal cavity 3022a under the action of gravity, thereby completing the material circulation of the phase change working medium.

[0067] In the process of continuous heat exchange, the phase change working medium circulates between the liquid and gas states, constantly undergoing phase change heat transfer to maintain the stable temperature of the battery cell 201. Through such a phase change heat transfer process, the heat exchange assembly 3 can effectively manage the heat of the battery cell 201, improve the temperature control efficiency, and ensure the uniformity of the battery cell 201 temperature, thereby improving the overall performance and safety of the battery pack.

[0068] In this embodiment, the surface of the heat exchange plate 301 close to each of the transverse portions 3021 is a straight plane, and the surface of the heat exchange plate 301 away from each of the transverse portions 3021 is at least partially convex in the direction away from each of the transverse portions 3021 to form the flow channel 3011. The straight plane design facilitates reducing the difficulty of fitting between the heat exchange plate 301 and the heat exchange member 302, increasing the fitting area between them, thereby reducing the contact thermal resistance and improving the heat exchange efficiency.

[0069] Optionally, a flexible heat-conducting layer 303 is arranged between the heat exchange plate 301 and each of the transverse portions 3021 for reducing the contact thermal resistance. The flexible heat-conducting layer 303 has a certain deformation ability and can adapt to the small gap between the battery cell 201 and the heat exchange plate 301, which is beneficial to reducing the contact thermal resistance and improving the heat exchange efficiency.

[0070] Further, the flexible heat-conducting layer 303 is a heat-conducting silica gel pad, heat-conducting grease, heat-conducting graphite film, heat-conducting foam, or heat-conducting plastic, etc. The material selection of the flexible heat-conducting layer 303 can be optimized according to actual needs and application scenarios. Different heat-conducting layer materials have different heat-conducting properties and costs, which are beneficial to meet the needs of different occasions.

[0071] In this embodiment, one side of the transverse portion 3021 close to the battery cell 201 is provided with a reinforcing groove 3021b.

[0072] The reinforcing groove 3021b not only avoids the low-voltage FPC and other components in the battery pack, but also improves the structural strength of the transverse portion 3021 to prevent the transverse portion 3021 from warping and deforming, thereby enabling the transverse portion 3021 to fully contact the conductive bar 202, thereby ensuring good cooling effect.

[0073] In this embodiment, the longitudinal portion 3022 is a wave-shaped structure matching the side surface of the cylindrical battery cell 201, or the longitudinal portion 3022 is a flat plate structure matching the side surface of the square shell-shaped battery cell 201. The longitudinal portion 3022 is designed according to the shape of the battery cell 201, so that the longitudinal portion 3022 matches the side surface of the battery cell 201, thereby increasing the heat exchange contact area.

[0074] Optionally, referring to Figure 2The end of the transverse part 3021 extends to a position protruding from the corresponding conductive row 202 in a direction away from the longitudinal part 3022 to cover the corresponding conductive row 202. The end of the transverse part 3021 extends to a position protruding from the conductive row 202, effectively covering the conductive row 202, protecting the conductive row 202 from damage caused by external factors, and improving the reliability of the battery pack.

[0075] In summary, the heat exchange assembly 3 and the battery pack provided by the embodiment have the following advantages:

[0076] ①It can simultaneously exchange heat with the end face and side face of the battery cell 201, improve the temperature control efficiency, and solve the problem of uneven temperature of the battery cell 201.

[0077] ②Through the phase change process of the phase change working medium, a large amount of heat is absorbed and released, further improving the heat exchange efficiency.

[0078] ③The design of the straight plane and the flexible heat conduction layer 303 reduces the contact thermal resistance and improves the heat exchange efficiency.

[0079] ④The end of the transverse part 3021 extends to protect the conductive row 202 and improves the reliability of the battery pack.

[0080] Finally, it should be noted that although the above embodiments have been described in the specification and drawings of the present application, they do not limit the patent protection scope of the present application. Any equivalent structure or equivalent flow replacement or modification based on the essential concept of the present application, using the content described in the specification and drawings of the present application, directly or indirectly, the technical solutions of the above embodiments are implemented in other related technical fields, etc., are all included in the patent protection scope of the present application.

Claims

1. A heat exchange assembly for heat exchanging a battery module (2) composed of a plurality of battery cells (201), characterized in that, The heat exchange assembly (3) comprises: a heat exchange plate (301) provided with a flow channel (3011) for flowing working medium; a plurality of heat exchange pieces (302) comprising a transverse part (3021) for heat exchange between the end face of the battery cell (201) and the heat exchange plate (301), and a longitudinal part (3022) fixed to one side of the transverse part (3021) close to the battery cell (201) for insertion between two adjacent rows of battery cells (201).

2. The heat exchange assembly of claim 1, wherein, The heat exchange piece (302) is internally provided with a phase change heat exchange cavity for containing phase change working medium.

3. The heat exchange assembly of claim 2, wherein, The phase change heat exchange cavity comprises a transverse cavity (3021a) in the transverse part (3021), and a longitudinal cavity (3022a) in the longitudinal part (3022) and communicating with the transverse cavity (3021a).

4. The heat exchange assembly of claim 1, wherein, The surface of the heat exchange plate (301) close to each transverse part (3021) is a straight plane, and the surface of the heat exchange plate (301) away from each transverse part (3021) is at least partially convex in the direction away from each transverse part (3021) to form the flow channel (3011).

5. The heat exchange assembly of claim 1, wherein, A flexible heat-conducting layer (303) is provided between the heat exchange plate (301) and each transverse part (3021) for reducing contact thermal resistance.

6. The heat exchange assembly of claim 1, wherein, One side of the transverse part (3021) close to the battery cell (201) is provided with a reinforcing groove (3021b).

7. The heat exchange assembly of claim 1, wherein, The longitudinal part (3022) is a wave-shaped structure matching the side surface of the cylindrical battery cell (201), or the longitudinal part (3022) is a flat plate structure matching the side surface of the square shell-shaped battery cell (201).

8. A battery pack, characterized by, A battery box (1) comprising an opening structure, a battery module (2) located in the battery box (1), and a heat exchange assembly (3) according to any one of claims 1-7, the heat exchange assembly (3) being arranged in heat exchange with the battery module (2) and covering the opening of the battery box (1).

9. The battery pack of claim 8, wherein, The battery module (2) comprises a plurality of battery cells (201), and a conductive row (202) electrically connecting the end faces of the battery cells (201); Between the side of each battery cell (201) and the corresponding longitudinal part (3022) of the heat exchange assembly (3), and / or between the side of each battery cell (201) and the corresponding conductive row (202) of the heat exchange assembly (3), a heat-conducting pad is provided.

10. The battery pack of claim 9, wherein, The end of the transverse part (3021) extends to a position protruding from the corresponding conductive row (202) in the direction away from the longitudinal part (3022), so as to cover the corresponding conductive row (202).

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