A battery pack

Abstract

The application relates to the technical field of new energy batteries, and discloses a battery pack which comprises single batteries and a first insulation piece, the single batteries each comprise a battery shell and an insulation layer wrapped on the surface of the battery shell, a first opening is arranged on the insulation layer, and the first openings of the single batteries are located on the same side of the battery pack; the first insulation piece comprises a first section and a second section which are connected with each other, at least a part of the first section is covered on the first surface, and the second section is arranged between two adjacent single batteries; the size of the first section is w mm, the size of the second section is d mm, and the distance between the edges of the first openings of the two adjacent single batteries is L mm, and the following condition is met: 60 <= L (w + d) <= 1110. The size between the first openings of the two adjacent single batteries and the size of the first insulation piece are limited, so that the heat dissipation performance is improved under the premise of meeting the insulation requirements of the two adjacent single batteries.

Description

[0001] This application is a divisional application of the patent application filed on August 14, 2025, with application number 202511137207.8 and invention title "A Battery Pack and Battery Assembly Thereof". Technical Field

[0002] This invention relates to the field of new energy battery technology, and in particular to a battery pack. Background Technology

[0003] A battery pack consists of multiple individual cells, each of which is wrapped with an insulating layer to ensure insulation between the individual cells. However, in order to ensure the heat dissipation of the metal casing of the individual cells, openings are usually made on the top and bottom surfaces of the casing, or both. These openings result in a short circuit risk between adjacent cells due to casing overlap, affecting the overall insulation performance of the battery. Summary of the Invention

[0004] The purpose of this invention is to provide a battery pack that can improve heat dissipation performance while meeting insulation requirements.

[0005] To achieve the above objectives, the present invention provides a battery pack comprising:

[0006] At least two individual cells are arranged sequentially along a first direction. Each individual cell includes a battery casing and an insulating layer covering the surface of the battery casing. The insulating layer has a first opening that exposes a portion of the battery casing. The first openings of at least two individual cells are located on the same side of the battery pack in a second direction. The first direction is perpendicular to the second direction. The first opening is disposed on a first surface of the battery casing. The battery casing has a terminal post extending out of the first opening.

[0007] A first insulating element includes a first segment and a second segment connected to each other, the first segment having at least a portion covering the first surface of at least one of the individual cells, and the second segment being disposed between two adjacent individual cells.

[0008] Wherein, the dimension of the first segment in the first direction is w mm, the dimension of the second segment in the second direction is d mm, and the minimum distance between the first opening edges of two adjacent single cells in the first direction is L mm, satisfying: 60 ≤ L (w + d) ≤ 1110;

[0009] The dimension of the single cell in the second direction is D mm, which satisfies: 0.01≤d / D≤1.

[0010] This invention provides a battery pack, which has the following advantages compared with the prior art:

[0011] The battery pack of the present invention includes a single cell and a first insulating member. The single cell includes a battery casing and an insulating layer covering the surface of the battery casing. A first section of the first insulating member rests on the surface of at least one single cell, and a second section rests on the surfaces of two adjacent single cells. By limiting the size between the first openings of the two adjacent single cells and the size of the first insulating member, the heat dissipation performance of the battery casing is improved while meeting the insulation requirements of the two adjacent single cells. This allows for timely heat dissipation of the internal cells of the battery, avoiding the safety risk of severe gas generation inside the battery and causing abnormal battery explosion. Attached Figure Description

[0012] Figure 1 This is a partial schematic diagram of the battery pack according to an embodiment of the present invention.

[0013] Figure 2 This is a schematic diagram of the battery pack according to an embodiment of the present invention.

[0014] Figure 3 yes Figure 2 Enlarged view of point α in the middle.

[0015] Figure 4 This is a schematic diagram of the first insulating member and the first single cell battery in an embodiment of the present invention.

[0016] Figure 5 yes Figure 4 A magnified view of point β in the middle.

[0017] Figure 6 This is a schematic diagram of the first insulating member and the first single cell in an embodiment of the present invention from another angle.

[0018] Figure 7 yes Figure 6 A magnified view of the γ region.

[0019] Figure 8 yes Figure 7 Enlarged view of the δ point.

[0020] Figure 9 This is a schematic diagram of one embodiment of the first insulating member and the second insulating member of the present invention.

[0021] Figure 10 This is a schematic diagram of another embodiment of the first insulating member and the second insulating member of the present invention.

[0022] Figure 11 This is a schematic diagram of one embodiment of the first insulating element and insulating layer of the present invention.

[0023] Figure 12This is a schematic diagram of one embodiment of the present invention, in which the insulating layer covers the battery casing.

[0024] Figure 13 This is a schematic diagram of one embodiment of the present invention, in which the electrode tab is disposed at one end in the first direction.

[0025] Figure 14 This is a schematic diagram of another embodiment of the first insulating element and insulating layer of the present invention.

[0026] In the diagram, 1 is the battery pack; 2 is the first insulating component; 3 is the base plate; 4 is the second adhesive layer; 5 is the second insulating component; 11 is the single cell; 11A is the first single cell; 11B is the second single cell; 12 is the first adhesive layer; 111 is the battery casing; 112 is the insulating layer; 113 is the first opening; 114 is the second opening; 1111 is the terminal post; 1112 is the cell body; 1113 is the tab; 1114 is the first surface; 1115 is the second surface; 21 is the first segment; 22 is the second segment; 211 is the first part; 212 is the second part; 51 is the third segment; 52 is the fourth segment; X is the first direction; Z is the second direction. Detailed Implementation

[0027] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0028] In the description of this invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0031] Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0032] Please refer to Figures 1-3 A battery pack according to an embodiment of the present invention includes: a first insulating member 2 and at least two individual cells 11.

[0033] Each individual battery cell 11 is arranged sequentially along the first direction X. Each individual battery cell 11 includes a battery casing 111 and an insulating layer 112 covering the surface of the battery casing 111. The insulating layer 112 is provided with a first opening 113, which exposes a part of the battery casing 111. The first openings 113 of at least two individual batteries 11 are located on the same side of the battery pack 1 in the second direction Z. The first direction X and the second direction Z are perpendicular. The first opening 113 is provided on the first surface 1114 of the battery casing 111.

[0034] A battery pack typically consists of multiple battery groups 1, each battery group 1 including at least two individual cells 11 arranged in sequence.

[0035] A battery pack typically includes an outer casing and multiple individual battery cells 11 disposed within the outer casing. The individual battery cells 11 are grouped together within the outer casing. The individual battery cells 11 can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc., and this embodiment is not limited to any of these. Each individual battery cell 11 typically includes a battery casing 111, a battery cell, and an electrolyte. The battery casing 111 is used to house the battery cell and the electrolyte, and the battery casing 111 has at least one positive electrode post and at least one negative electrode post. The battery cell includes one or more electrode assemblies, which are formed by stacking or winding positive electrode plates, negative electrode plates, and separators.

[0036] The positive electrode generally includes a positive current collector and a positive active material layer. The positive active material layer is directly or indirectly coated on the positive current collector. The positive current collector without the positive active material layer protrudes from the positive current collector with the positive active material layer. The positive current collector without the positive active material layer serves as a positive electrode tab. Multiple positive electrode tabs are stacked together and form an electrical connection with the positive electrode post. For example, the multiple stacked positive electrode tabs can be directly soldered to the positive electrode post to form an electrical connection; or, the battery cell assembly can also include a positive electrode adapter piece. The multiple stacked positive electrode tabs are soldered to one end of the positive electrode adapter piece, and the other end of the positive electrode adapter piece is soldered to the positive electrode post, so that the positive electrode tabs and the positive electrode post form an electrical connection.

[0037] The negative electrode generally includes a negative current collector and a negative active material layer. The negative active material layer is directly or indirectly coated on the negative current collector. The negative current collector without the negative active material layer protrudes from the negative current collector with the negative active material layer. The negative current collector without the negative active material layer serves as a negative electrode tab. Multiple negative electrode tabs are stacked together and form an electrical connection with the negative electrode post. For example, the stacked negative electrode tabs can be directly welded to the negative electrode post to form an electrical connection; alternatively, the battery cell assembly may also include a negative electrode adapter piece. The stacked negative electrode tabs are welded to one end of the negative electrode adapter piece, and the other end of the negative electrode adapter piece is welded to the negative electrode post, so that the negative electrode tabs and the negative electrode post form an electrical connection. The material of the separator is not limited; for example, it can be polypropylene or polyethylene.

[0038] In this embodiment, the single cell 11 is a square cell. In other embodiments, it can also be a round cell or a cell of other shapes.

[0039] Battery pack 1 is typically used in power-consuming fields such as passenger cars, commercial vehicles, energy storage, aircraft, and electric ships.

[0040] The insulating layer 112 is an insulating film or insulating coating applied to the surface of the battery casing 111, or both an insulating film and an insulating coating are applied simultaneously. It provides insulation and improves the insulation between two adjacent individual battery cells 11. The insulating film can be made of PET, PP, or PI, while the insulating coating can be made of polyacrylate, silicone, polyurethane, epoxy resin, etc. When the insulating layer 112 is applied to the battery casing 111, the insulating film can be adhered to the battery casing 111, and the insulating coating can be formed by spraying, UV curing, coating, or other methods.

[0041] While the insulating layer 112 provides insulation, it can also affect the heat dissipation of the battery casing 111. Providing a first opening 113 to expose a portion of the surface can improve the heat dissipation performance of the individual battery cell 11. In this embodiment, the first opening 113 exposes at least a portion of the top surface of the individual battery cell 11, that is, at least a portion of the first surface 1114.

[0042] Typically, in a battery pack, a base plate 3 is provided on one side of the battery pack 1. In this embodiment, the base plate 3 is provided on one side of the battery pack 1 in the second direction. The first surface 1114 is set parallel to the base plate 3. Parallelism is a relative concept. Excluding measurement and assembly errors, the surfaces parallel to the base plate 3 are the top surface and the bottom surface. The top surface and the bottom surface are set parallel to each other. The bottom surface is the surface closer to the base plate, and the top surface is the surface farther away from the base plate.

[0043] The first insulating member 2 includes a first segment 21 and a second segment 22 connected to each other. At least a portion of the first segment 21 covers the first surface 1114 of at least one single cell 11, and the first segment 21 is located on the side of the battery pack 1 near the first opening 113. The second segment 22 is disposed between two adjacent single cells 11.

[0044] The first segment 21 and the second segment 22 can be a single piece, or they can be separate pieces.

[0045] The first insulating member 2 can cover only one single cell 11, or it can cover two single cells 11 at the same time. The first segment 21 and the second segment 22 are different parts of the first insulating member 2. In this embodiment, the first insulating member 2 can be a bent angle iron or a T-shaped plate.

[0046] The first insulating element 2 can increase the creepage distance between two adjacent individual cells 11, thereby improving the insulation of the battery pack. However, the contact between the first insulating element 2 and the individual cell 11 can also affect the heat dissipation performance of the individual cell 11.

[0047] Please refer to Figure 3 , Figures 5-7 The first segment 21 has a dimension of w mm in the first direction X, and the second segment 22 has a dimension of d mm in the second direction Z. The minimum distance between the edges of the first opening 113 of two adjacent single cells 11 in the first direction X is L mm, satisfying: 60 ≤ L (w + d) ≤ 1110. In this embodiment, L (w + d) can take values ​​of 60, 120, 320, 540, 650, 710, 890, 960, 1110, etc.

[0048] When the above range is met, the insulation requirements of two adjacent individual cells 11 are met, and the portion of the first insulating element 2 covering the individual cell 11 is not excessive, thereby improving the heat dissipation performance of the individual cell 11. If the value is too small, the insulation requirements of two adjacent individual cells 11 will not be met, and the insulation risk will increase; if the value is too large, the portion of the first insulating element 2 covering the individual cell 11 will be excessive, resulting in poor heat dissipation performance.

[0049] In this embodiment, the arrangement direction of the individual battery cells 11 is the first direction X, that is, the length direction of the individual battery cells 11 is the first direction X, and the height direction of the individual battery cells 11 is the second direction Z. The first direction X and the second direction Z are perpendicular to each other, which means that the angle is between 85° and 95°.

[0050] When measuring dimensions L, w, and d, general length measuring tools such as rulers and tape measures can be used.

[0051] Specifically, when measuring L, the opening edge of any one of the two adjacent single cells 11 is taken as the reference edge. The minimum distance between the reference edge and the opening edge of the other single cell 11 is measured along the first direction X using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the minimum distance Lmm between the edges of the first opening 113 of the two adjacent single cells 11 in the first direction X.

[0052] When measuring w, take one end of the first segment 21 in the first direction X as the reference plane, and use a length measuring tool to measure the distance between the reference plane and the other end of the first segment 21 along the first direction X. Take the average value after multiple measurements to obtain the dimension of the first segment 21 in the first direction X as w mm.

[0053] When measuring d, take one end of the second segment 22 in the second direction Z as the reference plane, and use a length measuring tool to measure the distance between the reference plane and the other end of the second segment 22 along the second direction Z. Take the average value after multiple measurements to obtain the dimension of the second segment 22 in the second direction Z as d mm.

[0054] When the first insulating member 2 covers two individual cells 11 at the same time, the two adjacent individual cells 11 are respectively referred to as the first individual cell 11A and the second individual cell 11B. The first segment 21 includes a first part 211 and a second part 212 connected to each other. The first part 211 covers a part of the surface of the first individual cell 11A, the second part 212 covers a part of the surface of the second individual cell 11B, and the second segment 22 is connected to the first part 211 and / or the second part 212.

[0055] The second segment 22 is connected to the first part 211 and / or the second part 212. This means that the second segment 22 can be connected only to the first part 211, or it can be connected only to the second part 212, or a portion of the second segment 22 can be connected to the first part 211 and another portion of the second segment 22 can be connected to the second part 212. In other words, the second segment 22 is connected to both the first part 211 and the second part 212.

[0056] When the first segment 21 covers two individual cells 11 at the same time, it can further improve the insulation performance between the two adjacent individual cells 11 and reduce the risk of short circuit.

[0057] In some embodiments, please refer to Figure 11 and Figure 14 The projection of the first part 211 onto the first surface 1114 at least partially coincides with the projection of the first opening 113 onto the first surface 1114, satisfying: 180 ≤ L (w + d) ≤ 1110. Specifically, L (w + d) can take values ​​of 180, 360, 540, 870, 1040, 1110, etc.

[0058] When this range is met, the first opening 113 is directly opposite to the first part 211, that is, at least part of the first segment 21 of the first insulating member 2 is directly opposite to the first opening 113. Although this can significantly improve the heat dissipation performance, the creepage distance between adjacent single cells 11 is small, and there is a certain risk of insulation failure between adjacent single cells 11.

[0059] In some embodiments, the projected area of ​​the first opening 113 on the first surface 1114 is equal to the area of ​​the first surface 1114, satisfying: 330 ≤ L (w + d) ≤ 1100. L (w + d) can take values ​​of 330, 490, 620, 860, 970, 1110, etc.

[0060] In this case, the first surface 1114 is fully exposed by the first opening 113. When the first opening 113 of each of the two adjacent single cells 11 is isolated by the first insulating member 2, the creepage distance of the battery casing 111 of the two single cells 11 is small. When this range is met, the risk of insulation failure can be reduced while meeting the heat dissipation performance.

[0061] In some embodiments, the projected area of ​​the first opening 113 on the first surface 1114 is smaller than the area of ​​the first surface 1114, satisfying: 180 ≤ L (w + d) ≤ 770. L (w + d) can take values ​​of 180, 260, 310, 550, 770, etc.

[0062] In this case, a portion of the first surface 1114 is exposed by the first opening 113, which increases the creepage distance between adjacent individual cells 11, thereby effectively improving insulation performance. However, since the insulating layer 112 covers a larger portion of the battery casing 111, it also affects heat dissipation performance to some extent. When this range is met, a certain degree of heat dissipation can be guaranteed while satisfying insulation performance.

[0063] In some embodiments, please refer to Figure 4 The projected area of ​​the first opening 113 on the first surface 1114 is S1mm. 2 The area of ​​the first surface 1114 is S2mm. 2The condition is satisfied that 2% ≤ S1 / S2 ≤ 60%. S1 / S2 can take values ​​of 2%, 10%, 34%, 46%, 50%, 60%, etc.

[0064] When the above range is met, on the one hand, the insulation between adjacent individual cells 11 can be guaranteed, reducing the risk of short circuits caused by creepage or breakdown; on the other hand, when thermal runaway occurs in adjacent individual cells 11, a thermal buffer area can be formed through reasonable spatial layout to reduce the impact of high temperature thermal radiation on individual cells 11 and reduce the risk of thermal runaway of battery pack 1.

[0065] In some embodiments, please refer to Figure 11 The first surface 1114 of the first single cell 11A has an insulating layer 112, which is located between the battery casing 111 and the first part 211. The projection of the insulating layer 112 on the first surface 1114 is at least partially overlapping with the projection of the first part 211 on the first surface 1114.

[0066] An insulating layer 112 can also be provided on the first surface 1114 of the second cell 11B. The first segment 21 of the first insulating member 2 can also have the same position and cooperation as the second cell 11B and the first cell 11A. That is, the projection of the insulating layer 112 of the first cell 11A and the projection of the first insulating member 2 can be extended to all cells 11.

[0067] With this structure, the creepage distance between the first part 211 and the battery casing 111 of each individual battery 11 is increased, that is, the creepage distance between the first segment 21 of the first insulating member 2 and the battery casing 111 of each individual battery 11 is increased, and the creepage distance between two adjacent individual batteries 11 is also increased, thereby improving the insulation performance between two adjacent individual batteries 11.

[0068] In some embodiments, the insulating layer 112 is disposed at at least one end of the battery casing 111 of the first single cell 11A in the first direction X.

[0069] The insulating layer 112 wraps around the edge of the first surface 1114, increasing the creepage distance between two adjacent individual cells 11, thereby improving the insulation performance between two adjacent individual cells 11.

[0070] In some embodiments, at least a portion of the first opening 113 is disposed on at least one end of the first surface 1114 in the first direction X, such that the insulating layer 112 and the first surface 1114 are spaced apart at one edge in the first direction X.

[0071] With this structure, the first opening 113 is arranged at the end of the first surface 1114 in the first direction X, while the insulating layer 112 is centrally located, avoiding the increase in thermal resistance caused by the superposition of the first insulating element 2 in the second direction Z, and reducing the impact of the overlapping arrangement of the insulating layer 112 and the first insulating element 2 in the second direction Z on the heat dissipation performance of the battery casing 111.

[0072] In some embodiments, please refer to Figure 12 The edges of the first opening 113 and the first surface 1114 are spaced apart by a distance of k mm, satisfying: 3 ≤ k ≤ 5. k can take values ​​of 3, 3.5, 4, 4.5, 5, etc.

[0073] The first opening 113 and the edge of the first surface 1114 are spaced apart. This can be the case for all individual cells 11, for the first individual cell 11A, or for the second individual cell 11B.

[0074] When the above range is met, on the one hand, by ensuring the contact area between the insulation layer 112 and the battery casing 111, the connection strength between the two can be improved, and problems such as warping and deformation at the edge of the insulation layer 112 can be reduced; on the other hand, the creepage distance between adjacent individual cells 11 can be increased, thereby improving the insulation performance between adjacent individual cells 11.

[0075] When measuring dimension k, a general length measuring tool, such as a ruler or tape measure, can be used. Measure the distance between the two edges of the insulating layer 112 in the first direction X, take multiple measurements and average the result to obtain the edge spacing k mm between the first opening 113 and the first surface 1114.

[0076] In some embodiments, the first opening 113 of the first single cell 11A and the first portion 211 are spaced apart in the second direction Z, satisfying: 60 ≤ L (w + d) ≤ 900. L (w + d) can take values ​​of 60, 150, 270, 510, 700, 830, 900, etc.

[0077] With this structure, the first part 211 maintains a certain distance from the first surface 1114 exposed by the first opening 113, which can reduce the obstruction of the heat conduction path at the first opening 113 by the first part 211, so that heat can be dissipated to the outside more smoothly through the first opening 113, ensuring the heat dissipation performance of the single cell 11.

[0078] The first opening 113 and the first part 211 are spaced t mm apart in the second direction Z, satisfying: 4 ≤ t ≤ 20. t can take values ​​of 4, 6, 10, 13, 18, 20, etc.

[0079] When this range is met, it is possible to ensure the heat dissipation performance of the individual cell 11 while also ensuring the insulation performance between adjacent individual cells 11.

[0080] When measuring dimension t, a general length measuring tool, such as a ruler or tape measure, can be used. Using the first surface 1114 as the reference surface, the distance between the reference surface and the surface of the first part 211 facing the reference surface in the second direction Z is measured using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the distance t mm between the first opening 113 and the first part 211 in the second direction Z.

[0081] Battery pack 1 also includes a first adhesive layer 12, at least a portion of which is disposed between the first portion 211 and the first single cell 11A exposed on the first surface 1114 of the first opening 113. The first adhesive layer 12 connects the first single cell 11A and the first portion 211, and also satisfies: 60 ≤ L (w + d) ≤ 800. In this embodiment, L (w + d) can take values ​​of 60, 100, 200, 370, 590, 720, 800, etc.

[0082] The first adhesive layer 12 is used to fix the first insulating member 2, and the first adhesive layer 12 also has a certain insulating performance, thereby improving the insulation performance between two adjacent single cells 11, and the connection strength between the first part 211 and the first single cell 11A is also improved. When the above range is met, the setting of the first insulating member 2 can ensure the insulation performance between two adjacent single cells 11, while ensuring heat dissipation performance.

[0083] Please refer to Figure 13 The battery casing 111 has an electrode post 1111 extending out of the first opening 113, and also satisfies: 200 ≤ L (w + d) ≤ 1110. In this embodiment, L (w + d) can take values ​​of 200, 410, 610, 770, 980, 1110, etc.

[0084] The terminal 1111 is the component through which current flows. The terminal 1111 is not covered by the insulating layer 112. When the above range is met, heat dissipation performance can be ensured. Moreover, the voltage of the terminal 1111 is relatively large, and the above range can also meet the required insulation requirements.

[0085] In some embodiments, the second segment 22 has a dimension of d1 mm in the first direction X, and the distance between the first single cell 11A and the second single cell 11B in the first direction X is T mm, satisfying: d1 < T.

[0086] The second segment 22 is located between the first single cell 11A and the second single cell 11B. It meets the above-mentioned requirements, which facilitates the assembly of the second segment 22 and the installation of the first insulating component 2, thereby improving manufacturing efficiency. In addition, since the second segment 22 will have a gap with the first single cell 11A, or with the second single cell 11B, or with both the first single cell 11A and the second single cell 11B after installation, the heat dissipation effect of the single cell 11 is guaranteed.

[0087] When measuring dimensions d1 and T, general length measuring tools such as rulers and tape measures can be used.

[0088] Specifically, when measuring d1, one end face of the second segment 22 in the first direction X is used as a reference plane. The distance between the reference plane and the other end face is measured along the first direction X using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the dimension of the second segment 22 in the first direction X as d1mm. In this embodiment, the first segment 21 and the second segment 22 are perpendicular to each other, and both the first segment 21 and the second segment 22 are plate-shaped. d1 is also the thickness of the second segment 22.

[0089] When measuring T, the size of the gap formed between the first single cell 11A and the second single cell 11B is measured along the first direction X using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the distance T mm between the first single cell 11A and the second single cell 11B in the first direction X.

[0090] In some embodiments, the dimension of the single cell 11 in the second direction Z is D mm, satisfying: 0.01≤d / D≤1. In this embodiment, d / D can take values ​​such as 0.01, 0.15, 0.32, 0.54, 0.77, 0.89, 0.92, and 1.

[0091] When this range is met, the second segment 22 can provide good insulation without significantly affecting the heat dissipation of the individual battery 11.

[0092] When measuring dimension D, a general length measuring tool can be used, such as a ruler or tape measure.

[0093] Specifically, when measuring D, take any end face of the single cell 11 in the second direction Z as the reference plane, and use a length measuring tool to measure the distance between the reference plane and the other end face along the second direction Z. Take the average value after multiple measurements to obtain the dimension of the single cell 11 in the second direction Z as D mm.

[0094] The single battery cell 11 includes a cell body 1112 and a tab 1113. The tab 1113 is disposed at one end of the cell body 1112 in the first direction X, near the first insulating member 2, and also satisfies: 0.01≤d / D≤0.5. In this embodiment, d / D can take values ​​such as 0.01, 0.16, 0.30, 0.45, and 0.5.

[0095] The cell body 1112 can be formed by stacking or winding. The tab 1113 is used to connect to the electrode terminal. The cell body 1112 and the tab 1113 form the cell, and the cell is charged and discharged through the tab 1113.

[0096] The tab 1113 will emit a lot of heat. When the tab 1113 is located at the end of the cell body 1112 close to the first insulating member 2 in the first direction X, it meets the above range and can meet the heat dissipation requirements of the single cell 11.

[0097] The projection of the second segment 22 in the first direction X and the projection of the electrode 1113 in the first direction X are set at intervals.

[0098] With this structure, the second segment 22 will not be too long, thereby improving the heat dissipation effect of the single cell 11.

[0099] In some embodiments, the battery pack further includes a second adhesive layer 4, at least a portion of which is located between the individual battery cell 11 and the second segment 22, and connects the individual battery cell 11 and the second segment 22, and also satisfies: 60 ≤ L (w + d) ≤ 750. In this embodiment, L (w + d) can take values ​​of 60, 110, 260, 420, 540, 660, 750, etc.

[0100] The second adhesive layer 4 can fix the second segment 22 to the single cell 11, improve the connection strength between the first insulating member 2 and the single cell 11, prevent the first insulating member 2 from coming off, and the second adhesive layer 4 has certain insulation properties. When the above range is met, it can meet the insulation requirements between two adjacent single cells 11.

[0101] Please refer to Figure 3 and Figure 8The second segment 22 has a dimension of d1 mm in the first direction X, and the first segment 21 has a dimension of d2 mm in the second direction Z, satisfying: 0.01 ≤ d1 / d2 ≤ 5.4. In this embodiment, d1 / d2 can take values ​​such as 0.01, 1, 2.5, 3.9, 4.1, and 5.4.

[0102] Since the first segment 21 and the second segment 22 are plate-shaped perpendicular to each other, when the above range is met, the thickness of the first segment 21 and the second segment 22 will not have a large difference, which can improve the forming efficiency of the first insulating component 2.

[0103] When measuring dimension d2, a general length measuring tool can be used, such as a ruler or tape measure.

[0104] Specifically, when measuring d2, one end face of the first segment 21 in the second direction Z is used as a reference plane. The distance between the reference plane and the other end face is measured along the second direction Z using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the dimension of the first segment 21 in the second direction Z as d2mm. In this embodiment, d2 is also the thickness of the first segment 21.

[0105] This embodiment also provides a battery pack, including: a battery pack 1 and a base plate 3.

[0106] Battery pack 1 is mounted on base plate 3, and base plate 3 supports and fixes battery pack 1 in place.

[0107] Base plate 3 is used to support the battery. Base plate 3 can be made of metal materials such as stainless steel, aluminum alloy, and iron.

[0108] The base plate 3 can be the base plate 3 of the battery pack housing, or it can be a liquid cooling plate for cooling the battery pack 1.

[0109] In some embodiments, the base plate 3 is disposed on one side of the battery pack 1, and the first opening 113 is located on the side of the battery pack 1 opposite to the base plate 3, satisfying: 60 ≤ L (w + d) ≤ 900. Optional, L (w + d) can take values ​​of 60, 140, 210, 330, 490, 650, 780, 900, etc.

[0110] When this range is met, the first opening 113 is located on the top surface of the single cell 11, which enables the first opening 113 to have good heat dissipation capacity, so that the heat generated by the single cell 11 during operation can be dissipated through the first opening 113. In addition, it can ensure that the creepage distance between the first openings 113 of adjacent single cells 11 is not too small, and ensure the insulation between adjacent single cells 11.

[0111] When the base plate 3 is a heat exchange plate, a heat exchange channel is provided inside the heat exchange plate, satisfying: 300 ≤ L (w + d) ≤ 900. Optional, L (w + d) can take values ​​of 300, 440, 580, 740, 860, 900, etc.

[0112] The heat exchange plate can cool battery pack 1 and improve its heat dissipation efficiency. The heat exchange channel is a flow channel, and a heat exchange medium, such as refrigerant or coolant, can be introduced into the flow channel, thereby giving the heat exchange plate better heat dissipation performance and improving the heat dissipation efficiency of the heat exchange plate for battery pack 1.

[0113] The base plate 3 and the first opening 113 both serve as heat exchangers for the battery pack 1. When the above range is met, there is good heat exchange performance between adjacent individual cells 11, and there is also good insulation performance between adjacent individual cells 11.

[0114] In some embodiments, the base plate 3 is disposed on one side of the battery pack 1, and the first opening 113 is located on the side of the battery pack 1 facing the base plate 3, satisfying: 150 ≤ L (w + d) ≤ 1110. Optional, L (w + d) can take values ​​of 150, 230, 460, 530, 680, 850, 990, 1080, 1110, etc.

[0115] The first opening 113 is located on the bottom surface of the single cell 11. The first opening 113 and the base plate 3 can easily exchange heat. When this range is met, the heat dissipation performance at the first opening 113 can be ensured, while the risk of short circuit between the base plate 3 and the first opening 113 can be reduced, and the insulation performance between the base plate 3 and the single cell 11 can be guaranteed.

[0116] In some embodiments, please refer to Figure 10 The battery pack also includes a second insulating member 5, which includes a third segment 51 and a fourth segment 52 connected to each other. The insulating layer 112 also has a second opening 114, which is disposed on the second surface 1115 of the battery housing 111. At least a portion of the third segment 51 covers the second surface 1115 of at least one individual cell 11, and the fourth segment 52 is disposed between two adjacent individual cells 11.

[0117] In this case, the first surface 1114 is the top surface of the battery casing 111, and the second surface 1115 is the bottom surface of the battery casing 111.

[0118] The second opening 114, in conjunction with the first opening 113, allows heat dissipation for the individual battery 11 from both the first surface 1114 and the second surface 1115, improving the heat dissipation performance of the individual battery 11. Therefore, insulation requirements must also be met, so a second insulating element 5 is provided. The first insulating element 2 and the second insulating element 5 respectively improve the insulation effect of the first surface 1114 and the second surface 1115, that is, they lengthen the creepage distance between two adjacent individual batteries 11, thereby improving the insulation of the battery pack.

[0119] Please refer to Figure 9 The first insulating member 2 and the second insulating member 5 are connected, and the connection is located between two adjacent single cells 11.

[0120] The first insulating component 2 and the second insulating component 5 can be configured as an integral structure, such as an "I"-shaped structure. This configuration can improve the structural stability of the first insulating component 2 and the second insulating component 5 between the individual cells 11, and also increase the creepage distance, thereby improving the insulation performance.

[0121] To support the reasonableness of the above numerical range, this embodiment also includes insulation performance tests and temperature rise tests. Please refer to Table 1 for the test parameters and index data for each group.

[0122] For the insulation performance test, 10 sets of battery packs 1 of the same model were selected for both the embodiments and comparative examples. Each battery pack 1 includes two individual cells 11 with an insulating layer 112 on their surface. The two individual cells 11 are stacked, and a first opening 113 is made in the insulating layer 112 on the surface of the two individual cells 11. At the same time, a first insulating element 2 is provided between the two individual cells 11 on one side of the first opening 113 on the surface of the insulating layer 112. In different embodiments and comparative examples, the distance L between the first openings 113 of the two individual cells 11, the length w of the first segment 21 of the first insulating element 2, and the length d of the second segment 22 of the first insulating element 2 are shown in Table 1 below. All other parameters are the same. An insulation withstand voltage test was used. The tester measures the resistance between the first opening 113 of the insulating layer 112 on the surface of two individual cells 11. One output terminal of the insulation withstand voltage tester is connected to the first opening 113 area of ​​the insulating layer 112 on the surface of one individual cell 11, and the other end is connected to the first opening 113 area of ​​the insulating layer 112 on the surface of another individual cell 11. A DC voltage of 3000V is applied between the two output terminals, and the current is measured. The resistance between the first opening 113 of the insulating layer 112 on the surface of two individual cells 11 is calculated according to formula (1). The resistance between the two first openings 113 of 10 sets of battery packs 1 is measured and the average value is taken. The specific results are shown in Table 1. If the resistance is greater than or equal to 500MΩ, it is qualified; if it is less than 500MΩ, it is unqualified.

[0123] R=U / I(1)

[0124] For the temperature rise test, 10 sets of battery packs 1 of the same model were selected for different embodiments and comparative examples. Each battery pack 1 includes two individual cells 11 with an insulating layer 112 on their surface. The two cells are stacked, and a first opening 113 is made in the insulating layer 112 on the surface of the two individual cells 11. At the same time, a first insulating member 2 is provided between the two individual cells 11 on one side of the first opening 113 on the surface of the insulating layer 112 of the individual cells 11. In different embodiments and comparative examples, the distance L between the first openings 113 of the two individual cells 11, the length w of the first segment 21 of the first insulating member 2, and the length d of the second segment 22 of the first insulating member 2 are shown in Table 1 below. All other parameters are the same. The two individual cells are connected by a conductive busbar. After the cells 11 are connected in series, the two cells 11 are charged. First, they are discharged to 0% SOC at a discharge rate of 0.3C under the condition of 25℃, and then left to stand for 120min. Then, they are charged from 0% SOC to 100% SOC at a rate of 1C. The temperature of the first opening 113 region of the cell 11 at 20% SOC is measured and recorded as T1, and the temperature of the first opening 113 region of the cell 11 at 80% SOC is T2. The charging time of the cell 11 from 20% SOC to 80% SOC is tmin. The temperature rise rate is calculated according to formula (2). If the temperature rise rate is greater than 0.15℃ / min, it is unqualified. If the temperature rise rate is less than or equal to 0.15℃ / min, it is qualified.

[0125] Temperature rise rate = (T2 - T1) / t (2)

[0126] Table 1

[0127]

[0128] As can be seen from the experimental data in Table 1, L (w + d) When the above range is met, the single cell 11 can also have good heat dissipation performance while meeting the insulation requirements of two adjacent single cells 11.

[0129] Specifically, 8 ≤ L ≤ 30, where L can take values ​​of 8, 12, 16, 24, 28, 30, etc. When L is too small, the adhesion between the insulation layer 112 and the battery casing 111 is poor, and warping is likely to occur at the edge of the insulation layer 112, affecting the covering effect of the insulation layer 112. When L is too large, the distance between the insulation layer 112 and the battery casing 111 at the area of ​​maximum deformation of the battery casing 111 is relatively short when the battery casing 111 bulges, and the insulation layer 112 is likely to peel off from the battery casing 111 when the battery casing 111 bulges, thus affecting the insulation protection effect.

[0130] 2 ≤ w ≤ 12, where w can take values ​​of 2, 4, 8, 10, 12, etc. When w is too small, the first insulating component 2 cannot be effectively fixed to the single cell 11, thus affecting the assembly efficiency of the battery pack 1. When w is too large, the distance between the first insulating component 2 and the area of ​​maximum deformation of the battery casing 111 when it bulges is relatively close, and the first insulating component 2 is prone to cracking when the casing bulges.

[0131] 1.5 ≤ d ≤ 120, where d can take values ​​of 1.5, 13, 39, 55, 81, 97, 106, 114, 120, etc. When d is too small, the fixing effect between the first insulating component 2 and the battery pack 1 is poor, and the first insulating component 2 is prone to detachment. When d is too large, it will affect the installation of the individual battery 11 and the base plate 3, thus affecting the assembly efficiency.

[0132] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A battery pack, characterized in that, include: At least two individual cells are arranged sequentially along a first direction. Each individual cell includes a battery casing and an insulating layer covering the surface of the battery casing. The insulating layer has a first opening that exposes a portion of the battery casing. The first openings of at least two individual cells are located on the same side of the battery pack in a second direction. The first direction is perpendicular to the second direction. The first opening is disposed on a first surface of the battery casing. The battery casing has a terminal post extending out of the first opening. A first insulating element includes a first segment and a second segment connected to each other, the first segment having at least a portion covering the first surface of at least one of the individual cells, and the second segment being disposed between two adjacent individual cells. Wherein, the dimension of the first segment in the first direction is w mm, the dimension of the second segment in the second direction is d mm, and the minimum distance between the first opening edges of two adjacent single cells in the first direction is L mm, satisfying: 60 ≤ L (w + d) ≤ 1110, 8 ≤ L ≤ 30, 2 ≤ w ≤ 12, 1.5 ≤ d ≤ 120; The dimension of the single cell in the second direction is D mm, which satisfies: 0.01 ≤ d / D ≤ 1.

2. The battery pack according to claim 1, characterized in that: Two adjacent single cells are referred to as the first single cell and the second single cell, respectively. The first segment includes a first part and a second part connected to each other. The first part covers a portion of the surface of the first single cell, and the second part covers a portion of the surface of the second single cell. The second segment is connected to the first part and / or the second part.

3. The battery pack according to claim 2, characterized in that: The projection of the first portion onto the first surface at least partially coincides with the projection of the first opening onto the first surface, satisfying: 180 ≤ L (w + d) ≤ 1110.

4. The battery pack according to claim 3, characterized in that: The projected area of ​​the first opening on the first surface is equal to the area of ​​the first surface, satisfying: 330 ≤ L (w + d) ≤ 1100.

5. The battery pack according to claim 3, characterized in that: The projected area of ​​the first opening on the first surface is smaller than the area of ​​the first surface, satisfying: 180 ≤ L (w + d) ≤ 770.

6. The battery pack according to claim 5, characterized in that: The projected area of ​​the first opening on the first surface is S1mm. 2 The area of ​​the first surface is S2mm. 2 The following condition must be met: 2% ≤ S1 / S2 ≤ 60%.

7. The battery pack according to claim 2, characterized in that: The first surface of the first single cell has the insulating layer, which is located between the battery casing and the first part, and the projection of the insulating layer on the first surface at least partially overlaps with the projection of the first part on the first surface.

8. The battery pack according to claim 7, characterized in that: The insulating layer is disposed at at least one end of the battery casing of the first single cell in the first direction.

9. The battery pack according to claim 7, characterized in that: The first opening is at least partially disposed at at least one end of the first surface in the first direction, such that the insulating layer and the first surface are spaced apart at one edge in the first direction.

10. The battery pack according to claim 2, characterized in that: The battery pack further includes a first adhesive layer, at least a portion of which is disposed between the first portion and the first surface of the first individual cell, and the first adhesive layer connects the first individual cell and the first portion, and also satisfies: 60 ≤ L (w + d) ≤ 800.

11. The battery pack according to claim 1, characterized in that: The single cell includes a cell body and a tab. The tab is disposed at one end of the cell body in the first direction near the first insulating member, and also satisfies: 0.01 ≤ d / D ≤ 0.

5.

12. The battery pack according to claim 11, characterized in that: The projection of the second segment in the first direction is spaced apart from the projection of the tab in the first direction.

13. The battery pack according to claim 1, characterized in that, Also includes: The second adhesive layer, at least a portion of which is located between the single cell and the second segment and connects the single cell and the second segment, also satisfies: 60 ≤ L (w + d) ≤ 750.

14. The battery pack according to claim 11, characterized in that: The second segment has a dimension of d1mm in the first direction, and the first segment has a dimension of d2mm in the second direction, satisfying: 0.01≤d1 / d2≤5.

4.

15. The battery pack according to claim 1, characterized in that: The first direction is the length direction of the single battery cell.

16. The battery pack according to claim 1, characterized in that: The insulating layer is an insulating film or an insulating coating. The insulating film is made of one of PET, PP, or PI. The insulating coating is made of one of polyacrylate, silicone, polyurethane, or epoxy resin.

17. The battery pack according to claim 1, characterized in that: The first segment and the second segment are integrally formed.

18. The battery pack according to claim 1, characterized in that: The first segment and the second segment are separate structures.

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