Battery pack

Abstract

The utility model relates to the technical field of battery packs, and discloses a battery pack which comprises a battery pack and a heating structure, the battery pack is sequentially provided with at least two columns along a first direction, and each column comprises at least two single batteries which are sequentially arranged along a second direction; the heating structure comprises two heating pieces and a heat insulation piece clamped between the two heating pieces, the two opposite surfaces of the two heating pieces are a first large surface and a second large surface respectively, and the heat insulation piece is clamped between the first large surface and the second large surface; the heat conductivity coefficient K of the heat insulation piece is less than or equal to 0.05 W / m.k; the heating structure is arranged between two adjacent columns of battery packs, and the two heating pieces are in heat conduction connection with the two adjacent columns of battery packs respectively; wherein the first direction is perpendicular to the second direction. According to the battery pack disclosed by the utility model, heat between the two heating pieces can be separated through the heat insulation film, so that the heating effect of the heating pieces is prevented from being influenced by heat transfer between the two heating pieces, and the heat balance of the single batteries on the two sides in the first direction can be ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packs, and in particular to a battery pack. Background Art

[0002] Lithium batteries are widely used in various electrical devices to perform functions. However, in low temperature environments, the electrolyte in the battery pack stagnates, the internal resistance decreases, and lithium condensation may form at the cathode, affecting the life of the battery pack.

[0003] In the related art, a battery pack usually includes at least two columns of battery packs arranged in sequence, and a heating film is arranged between two adjacent columns of battery packs to heat the battery packs. However, due to the difference in the size of the single cells in the two columns of battery packs, the heating film cannot be in close contact with all the single cells in the two columns of battery packs at the same time, resulting in differences in the heating effect of the heating film. If two layers of heating films are arranged on the opposite side of the two columns of battery packs to heat the two columns of battery packs respectively through the two layers of heating films, although the two layers of heating films can be well in close contact with the single cells in the two columns of battery packs respectively; however, when one side of the single cell is close to the two layers of heating films and one side has only one layer of heating film, the heat exchange between the two layers of heating films will affect the thermal balance on both sides of the single cell. Utility Model Content

[0004] In view of this, the utility model provides a battery pack to solve the problem that the heat exchange between two layers of heating films will affect the thermal balance on both sides of the single battery.

[0005] The utility model provides a battery pack, comprising:

[0006] A battery pack, wherein at least two columns are sequentially arranged along a first direction, and each column includes at least two single cells sequentially arranged along a second direction;

[0007] A heating structure, comprising two heating elements and a heat insulating element sandwiched between the two heating elements, wherein two opposing surfaces of the two heating elements are respectively a first large surface and a second large surface, and the heat insulating element is sandwiched between the first large surface and the second large surface; a thermal conductivity coefficient K of the heat insulating element satisfies K≤0.05W / m·k; the heating structure is arranged between two adjacent columns of the battery packs, and the two heating elements are respectively thermally connected to the two adjacent columns of the battery packs;

[0008] The first direction is perpendicular to the second direction.

[0009] Beneficial effects: Two heating elements are arranged between two columns of battery packs, each column of battery packs is matched with a heating element, and a heat-insulating film is arranged between the two heating elements, which can ensure that each single cell in the battery pack can be closely attached to its matched heating element, thereby ensuring the uniformity of heating of the single cell by the heating element; the heat between the two heating elements can be separated by the heat-insulating film, thereby preventing heat transfer between the two heating elements and affecting the heating effect of the heating elements; and the temperature of the side of the single cell close to the two heating elements can be prevented from being higher than that of the side close to only one heating element, thereby ensuring the thermal balance of the two sides of the single cell in the first direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0011] Figure 1 An exploded view of the installation of a battery pack according to an embodiment of the utility model;

[0012] Figure 2 A schematic diagram of a battery pack according to an embodiment of the utility model;

[0013] Figure 3 for Figure 2 A is a partial enlarged schematic diagram;

[0014] Figure 4 This is a schematic diagram of the structure of a battery pack according to an embodiment of the utility model;

[0015] Figure 5 This is a schematic diagram of a heating element according to an embodiment of the utility model.

[0016] Description of reference numerals:

[0017] 1. Battery pack; 11. Single battery; 2. Heating structure; 21. Heating element; 22. Heat insulation element; 3. Box. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0019] Combine the following Figures 1 to 5 The embodiments of the present invention are described.

[0020] According to an embodiment of the utility model, a battery pack is provided, comprising a battery group 1 and a heating structure 2; the battery group 1 is sequentially provided with at least two columns along a first direction, and each column comprises at least two single batteries 11 sequentially arranged along a second direction; the heating structure 2 comprises two heating elements 21 and a heat insulating element 22 sandwiched between the two heating elements 21, and the two opposite surfaces of the two heating elements 21 are respectively a first large surface and a second large surface, and the heat insulating element 22 is sandwiched between the first large surface and the second large surface; the thermal conductivity K of the heat insulating element 22 satisfies, K≤0.05W / m·k; the heating structure 2 is arranged between two adjacent columns of battery groups 1, and the two heating elements 21 are respectively thermally connected to the two adjacent columns of battery groups 1; wherein the first direction is perpendicular to the second direction.

[0021] Two heating elements 21 are arranged between two columns of battery packs 1, and each column of battery packs 1 is matched with a heating element 21. A heat-insulating film is also arranged between the two heating elements 21, which can ensure that each single battery 11 in the battery pack 1 can be closely attached to the heating element 21 matched with it, and ensure the uniform heating of the single battery 11 by the heating element 21; and the heat between the two heating elements 21 can be separated by the heat-insulating film to prevent the heat transfer between the two heating elements 21 from affecting the heating effect of the heating element 21; since the battery pack 1 is provided with at least two columns along the first direction, and the two outermost columns of battery packs 1 are both thermally connected to a heating element, therefore, the heat-insulating element 22 is sandwiched between the two heating elements 21, which can also prevent the temperature of the side of the single battery 11 close to the two heating elements 21 from being higher than the temperature of the side close to only one heating element, and ensure the heat balance of the two sides of the single battery 11 in the first direction. And since the thermal conductivity K of the heat-insulating element 22 satisfies K≤0.05W / m·k, it can have a better heat-insulating effect.

[0022] In this embodiment, the heating element 21 refers to a heating element 21 with a heating core to achieve the purpose of active temperature increase. The heating core can be a resistance wire, which can be used to heat the battery pack 1 after being powered on.

[0023] Specifically, if the heating element 21 is approximately a cuboid, the first large surface and the second large surface are the surfaces with the largest areas among the six surfaces of the respective cuboids. The battery pack further includes a box 3, in which the battery pack and the heating structure are both arranged.

[0024] In a specific embodiment, the thermal conductivity K of the thermal insulation member 22 is 0.05 W / m·k.

[0025] In one embodiment, the heating element 21 is bonded to the battery pack 1 , and the heating element 21 is bonded to the heat insulating element 22 , and the bonding strength between the heating element 21 and the battery pack 1 is greater than the bonding strength between the heating element 21 and the heat insulating element 22 .

[0026] Since the bonding strength between the heating element 21 and the battery pack 1 is greater than the bonding strength between the heating element 21 and the thermal insulation element 22, after the battery pack 1 vibrates or expands, the bonding between the heating element 21 and the thermal insulation element 22 will lose its viscosity first due to the shear force, thereby avoiding failure of the bonding between the heating element 21 and the battery pack 1.

[0027] In a specific implementation, two opposite sides of the heat insulating member 22 are both adhesively backed so as to be bonded to the heating members 21 on both sides respectively; when the battery packs are stacked, the heat insulating member 22 is first bonded to the heating member 21 on one side, and the other side is pressed tightly by the tooling when the battery packs 1 on both sides are stacked.

[0028] In one embodiment, the heating element 21 includes a body and a heating core; the heating core is arranged inside the body; and at least a portion of the projection of the thermal insulation element 22 on the body covers the heating core.

[0029] At least a portion of the projection of the heat insulating element 22 on the main body covers the heating core, and the heating core in the heating element 21 can be insulated as a whole to ensure a good heat insulating effect.

[0030] Specifically, a through hole is provided on the body, and the through hole is arranged on a side facing the battery pack 1 .

[0031] In one embodiment, the thermal insulation 22 is a one-piece structure.

[0032] The one-piece structure is easy to form, saves the process of connection, and has a good heat insulation effect.

[0033] In one embodiment, the thermal insulation member 22 is composed of at least two separate members connected as one body.

[0034] The heat insulating member 22 is composed of at least two separate members connected as one body, and the heat insulating member 22 can be manufactured according to actual needs without excessive cutting.

[0035] In one embodiment, the ratio A of the projection area of ​​the heat insulating member 22 on the body to the area of ​​the body satisfies 1≤A≤1.1. Specifically, the area of ​​the body refers to the area enclosed by the outer contour of the body of the heating member 21 .

[0036] The area of ​​the heat insulating member 22 is greater than or equal to the area of ​​the main body, which can ensure the heat insulating effect of the heat insulating member 22 on the entire heating core.

[0037] In a specific embodiment, the ratio A of the projected area of ​​the thermal insulation member 22 on the body to the area of ​​the body is 1, that is, the projected area of ​​the thermal insulation member 22 on the body is consistent with the area of ​​the heating core.

[0038] In another specific embodiment, the ratio A of the projected area of ​​the thermal insulation member 22 on the main body to the area of ​​the main body is 1.1.

[0039] In one embodiment, the heating element 21 is a silicone heating pad, which has a low cost, a certain deformation space, can adapt to more connection environments, and has a better heat conduction effect.

[0040] In one embodiment, the sum W of the thickness of the two heating elements 21 and the thickness of the heat insulating element 22 satisfies 2mm≤W≤4mm.

[0041] The two heating elements 21 and the heat insulating element 22 together constitute the heating structure 2. When the thickness of the heating structure 2 is too large, the gap between the batteries is too large, which is not conducive to the space utilization of the entire battery pack. When the thickness of the heating structure 2 is too small, the heating element 21 or the heat insulating element 22 is too thin and easily damaged.

[0042] In a specific embodiment, the sum W of the thickness of the two heating elements 21 and the thickness of the heat insulating element 22 is 2 mm.

[0043] In another specific embodiment, the sum W of the thickness of the two heating elements 21 and the thickness of the heat insulating element 22 is 4 mm.

[0044] Specifically, considering factors such as the gap between the two sides of the battery compartment, the thickness of the two heating elements 21 is 0.34mm*2=0.68mm (including the thickness of the adhesive backing), and the thermal insulation element 22 is generally greater than 1.5mm (including double-sided adhesive backing) in consideration of the surface degree and minimum thickness manufactured by the supplier.

[0045] In one embodiment, a ratio B of the thickness of the heating element 21 to the thickness of the heat insulating element 22 satisfies 0.1≤B≤0.2.

[0046] In a specific embodiment, the ratio B of the thickness of the heating element 21 to the thickness of the heat insulating element 22 is 0.1.

[0047] Specifically, in another embodiment, the ratio B of the thickness of the heating element 21 to the thickness of the heat insulating element 22 is 0.2.

[0048] In one embodiment, the material of the thermal insulation member 22 is MPV foam, or MPP foam, or EVA flame retardant foam.

[0049] The material of the heat insulating member 22 is MPV foam, or MPP foam, or EVA flame-retardant foam, which can not only play a heat insulating role, but also has elasticity so that the heating members 21 on both sides are in close contact with the corresponding single cells 11 of the battery pack 1 .

[0050] Specifically, the MPP foam may be 10 times MPP foam or 25 times MPP foam, wherein 10 times and 25 times represent the foaming ratio.

[0051] In one embodiment, the elastic modulus E of the thermal insulation member 22 satisfies 0.4 MPa≤E≤1 MPa.

[0052] Due to the dimensional tolerance of the single cells 11 , the heating element 21 may not be in close contact with all the single cells 11 . The heat insulating element 22 is elastic, so the heat insulating element 22 supports the heating element 21 , ensuring that the heating element 21 is in close contact with all the single cells 11 .

[0053] In a specific embodiment, the elastic modulus E of the thermal insulation member 22 is 0.4 MPa.

[0054] In another specific embodiment, the elastic modulus E of the thermal insulation member 22 is 0.6 MPa.

[0055] In one embodiment, each single battery 11 of the battery pack 1 is disposed in close contact with the heating element 21 .

[0056] The side of each single battery 11 of the battery pack 1 facing the heating element 21 is arranged in close contact with the side of the heating element 21 without any spacer in between, so as to avoid the spacer affecting the heat transfer.

[0057] Specifically, the side of the single battery 11 facing the heating element 21 is a narrow side of the battery.

[0058] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery pack, characterized in that: include: A battery pack (1) is provided with at least two columns arranged in sequence along a first direction, each column comprising at least two single cells (11) arranged in sequence along a second direction; A heating structure (2) comprising two heating elements (21) and a heat insulating element (22) sandwiched between the two heating elements (21); two opposing surfaces of the two heating elements (21) are respectively a first large surface and a second large surface; the heat insulating element (22) is sandwiched between the first large surface and the second large surface; a thermal conductivity coefficient K of the heat insulating element (22) satisfies K≤0.05 W / m·k; the heating structure (2) is arranged between two adjacent columns of the battery packs (1), and the two heating elements (21) are respectively thermally connected to the two adjacent columns of the battery packs (1); The first direction is perpendicular to the second direction.

2. The battery pack according to claim 1, characterized in that: The heating element (21) comprises: ontology; A heating core is arranged inside the main body; at least a portion of the projection of the heat insulating member (22) on the main body covers the heating core.

3. The battery pack according to claim 2, characterized in that: The ratio A of the projection area of ​​the heat insulating member (22) on the main body to the area of ​​the main body satisfies 1≤A≤1.

1.

4. The battery pack according to claim 2, characterized in that: The heating element (21) is a silica gel heating pad.

5. The battery pack according to any one of claims 1 to 4, characterized in that: The sum W of the thickness of the two heating elements (21) and the thickness of the heat insulating element (22) satisfies 2mm≤W≤4mm.

6. The battery pack according to any one of claims 1 to 4, characterized in that: The ratio B of the thickness of the heating element (21) to the thickness of the heat insulating element (22) satisfies 0.1≤B≤0.

2.

7. The battery pack according to claim 1, characterized in that: The material of the thermal insulation element (22) is MPV foam, or MPP foam, or EVA flame-retardant foam.

8. The battery pack according to claim 7, characterized in that: The elastic modulus E of the thermal insulation member (22) satisfies 0.4MPa≤E≤1MPa.

9. The battery pack according to any one of claims 1 to 4 or 7 or 8, characterized in that: Each of the single cells (11) of the battery pack (1) is arranged in close contact with the heating element (21).

10. The battery pack according to any one of claims 1 to 4 or 7 or 8, characterized in that: The heating element (21) is bonded to the battery pack (1), and the heating element (21) is bonded to the heat insulating element (22), and the bonding strength between the heating element (21) and the battery pack (1) is greater than the bonding strength between the heating element (21) and the heat insulating element (22).

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