Battery and electric equipment

Abstract

The invention discloses a battery and electric equipment, the battery comprises a single battery and a temperature adjusting plate, the single battery comprises a battery shell and an electrode assembly arranged in the battery shell, the electrode assembly comprises a plurality of electrode plates, the plurality of electrode plates are stacked along a first direction, and the temperature adjusting plate is arranged in the battery shell. At least two positive plates in the plurality of electrode plates are arranged discontinuously, the first direction is the thickness direction of the electrode plates, the temperature adjusting plate is in heat conduction contact with the first side wall of the battery shell corresponding to the side edges of the electrode plates, and a temperature adjusting medium is introduced into the temperature adjusting plate to adjust the temperature of the single battery. The battery disclosed by the invention is high in overall heat dissipation capability and good in cooling effect.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to a battery and an electrical device. Background Technology

[0002] In recent years, with the popularization of new energy vehicles, power batteries, as the power source for these vehicles, have also developed rapidly. To ensure the safety and stability of power batteries, they need to be cooled and dissipated using temperature regulating plates and other means. However, in actual use, power batteries still suffer from poor cooling performance. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, this invention proposes a battery with high overall heat dissipation capacity and good cooling effect.

[0005] The present invention also proposes an electrical device including the above-described battery.

[0006] The battery of this invention includes:

[0007] A single battery cell includes a battery casing and an electrode assembly disposed within the battery casing. The electrode assembly includes multiple electrode sheets stacked along a first direction, and at least two positive electrode sheets among the multiple electrode sheets are not continuously disposed. The first direction is the thickness direction of the electrode sheets.

[0008] A temperature regulating plate is provided, which is in thermal contact with the first sidewall of the battery case corresponding to the side of the electrode sheet, and a temperature regulating medium is introduced into the temperature regulating plate to regulate the temperature of the individual battery cell.

[0009] In some embodiments, the electrode sheet includes two first sides disposed opposite to each other along a second direction and two second sides disposed opposite to each other along a third direction. The first sidewall and the second sidewall of the electrode sheet are disposed opposite to each other in the third direction. The second direction is perpendicular to the first direction, and the third direction is perpendicular to both the first and second directions. The temperature regulating plate is in thermal contact with the first sidewall.

[0010] In some embodiments, the single cell further includes electrode terminals disposed on the sidewall of the battery casing along the second direction or the third direction.

[0011] In some embodiments, a thermally conductive medium is included, which is disposed between the first sidewall and the electrode assembly.

[0012] In some embodiments, the thermal conductivity of the thermally conductive medium is k1, the distance between the electrode assembly and the first sidewall is L1, the area of ​​the first sidewall is A1, and L1 / (k1*A1)≤9.9K / W.

[0013] In some embodiments, the thermal conductivity of the electrode assembly in the third direction is k2, the thermal conductivity of the electrode assembly in the second direction is k3, and the thermal conductivity of the electrode assembly in the first direction is k4, where k2 > k4 and k3 > k4.

[0014] In some embodiments, there are multiple temperature regulating plates, each of which extends along the first direction. The multiple temperature regulating plates are arranged at intervals in the third direction, and multiple individual batteries arranged along the first direction are provided between two adjacent temperature regulating plates.

[0015] In some embodiments, the battery casing includes a second sidewall arranged opposite to the electrode sheet in the first direction, and the thermal resistance R1 between the electrode assembly and the first sidewall is not greater than the thermal resistance R2 between the electrode assembly and the second sidewall.

[0016] The battery casing has a third sidewall perpendicular to the first sidewall and the second sidewall, and the thermal resistance R1 is not greater than the thermal resistance R3 between the electrode assembly and the third sidewall of the battery casing.

[0017] In some embodiments, a housing is included, and multiple individual cells are assembled inside the housing. The housing is filled with a potting medium, and the potting medium is distributed between the housing and the individual cells, as well as between two adjacent individual cells.

[0018] In some embodiments, the battery casing has a protrusion disposed between two individual cells to form a gap between the two individual cells for filling with potting medium.

[0019] In some embodiments, a battery module is included, the battery module being disposed within the housing, the battery module comprising a plurality of individual cells arranged along the first direction or in a third direction orthogonal to the first direction, the thermal conductivity of the potting medium being k5, the distance between the battery module and the sidewall of the housing being L2, the lateral surface area of ​​the individual cell facing the sidewall of the housing being A2, and 0.55K / W≤L2 / (k5*A2)≤217K / W.

[0020] In some embodiments, the expansion force of the single cell is F1, the battery casing includes a second sidewall arranged opposite to the electrode sheet in the first direction, the area of ​​the second sidewall is S1, and the expansion stress of the single cell is M1 = F1 / S1.

[0021] The thickness of the potting medium between the second sidewalls of two adjacent single cells is L3, the maximum expansion displacement of the single cell is α, and the maximum compressive strain of the potting medium is β=α / L3;

[0022] Furthermore, when the compressive strain of the potting medium is β, the compressive stress corresponding to the potting medium is M2, and M1≥M2.

[0023] In some embodiments, the maximum voltage of the battery is U1, and the insulation voltage of the potting medium in the first direction is U2, where U2 ≥ 3.7U1;

[0024] And / or, the first-order free mode of the battery is ≥55Hz.

[0025] In some embodiments, the battery casing includes a second sidewall arranged opposite to the electrode sheet in the first direction, the gap width between the second sidewalls of two adjacent individual cells is L4, and the capacity of the individual cell is Q1, 17.2Ah / mm≤Q1 / L4≤547.3Ah / mm.

[0026] In some embodiments, the temperature regulating plate is provided with a plurality of medium channels for the flow of temperature regulating medium, the cross-sectional area of ​​the medium channels is S2, the cross-sectional area of ​​the temperature regulating plate perpendicular to the extending direction of the temperature regulating plate is S3, and 50% ≤ S2 / S3 ≤ 99%.

[0027] In some embodiments, a chamfer R1 is provided between two adjacent channel walls of each medium channel, and 0.1mm≤R1≤5mm;

[0028] And / or, the maximum voltage of the battery is U1, the insulation voltage of the temperature regulating plate is U3, and U3 ≥ 7.5U1.

[0029] The electrical devices in this embodiment of the invention include batteries as described in any of the above embodiments.

[0030] Beneficial effects: In the battery and electrical device of the present invention, the temperature regulating plate of the battery is disposed on the periphery of the electrode sheet and corresponds to the side edge of the electrode sheet. Compared with the case in the related art where the temperature regulating plate is disposed on the wall of the single cell 1 parallel to the two planes on both sides of the electrode sheet 131 in the thickness direction, the thermal resistance of heat conduction along the extension direction of the electrode sheet is much smaller than the thermal resistance of heat conduction between the two electrode sheets, thereby improving the heat exchange efficiency between the single cell and the temperature regulating plate, and thus improving the overall heat dissipation performance and cooling effect of the battery. Attached Figure Description

[0031] Figure 1 This is an exploded view of a single battery cell and a temperature regulating plate according to an embodiment of the present invention.

[0032] Figure 2 This is a schematic cross-sectional view of a single cell and its AA section according to an embodiment of the present invention.

[0033] Figure 3 yes Figure 2 A perspective view of a single cell in the middle, taken from the first direction.

[0034] Figure 4 yes Figure 2 A third-angle perspective view of a single cell.

[0035] Figure 5 This is an exploded view of the battery module and temperature control plate according to an embodiment of the present invention.

[0036] Figure 6 This is an exploded view of the battery casing according to an embodiment of the present invention.

[0037] Figure label:

[0038] 1-Single cell; 11-Battery casing; 111-First sidewall; 112-Second sidewall; 113-Third sidewall; 12-Electrode terminal; 13-Electrode assembly; 131-Electrode sheet; 1311-First side; 1312-Second side; 132-Separator; 14-Heat-conducting medium;

[0039] 2-Temperature regulating plate;

[0040] 3-Pipelines;

[0041] 4-Outer shell; 41-Top cover; 42-Bottom shell;

[0042] 5-Potting medium;

[0043] 6-Battery module. Detailed Implementation

[0044] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0045] like Figure 1 As shown, the battery in this embodiment of the invention includes a single cell 1 and a temperature regulating plate 2, wherein the single cell 1 can be a prismatic cell. Figure 1 The first direction can be the width direction of the single cell 1, the second direction can be the height direction of the single cell 1, and the third direction can be the length direction of the single cell 1.

[0046] The single cell 1 includes a battery case 11 and an electrode assembly 13 disposed within the battery case 11. The electrode assembly 13 includes a plurality of electrode sheets 131, which are stacked along a first direction, and at least two positive electrode sheets among the plurality of electrode sheets 131 are not continuously arranged. The first direction is the thickness direction of the electrode sheets 131.

[0047] For example, such as Figure 2 As shown, the battery casing 11 can be square-shaped, and the electrode assembly 13 is disposed inside the battery casing 11. The electrode assembly 13 can be manufactured by a lamination process. The multiple electrode plates 131 of the electrode assembly 13 can include multiple positive electrode plates and multiple negative electrode plates. The multiple positive electrode plates and multiple negative electrode plates can be arranged alternately in the first direction.

[0048] It should be noted that, since the multiple electrode sheets 131 of the electrode assembly 13 are processed by stacking, compared with the winding molding process, any two positive electrode sheets of the electrode assembly 13 in this embodiment are non-continuous, that is, there is no direct connection between two adjacent positive electrode sheets except at the tab.

[0049] The temperature regulating plate 2 and the side of the electrode sheet 131 are in thermal contact with the first side wall 111 of the battery case 11, and the temperature regulating plate 2 is used to introduce a temperature regulating medium to regulate the temperature of the single cell 1.

[0050] For example, the electrode sheet 131 can be considered as a sheet-like structure, and the shape of the electrode sheet 131 can be rectangular. In this case, the sides of the electrode sheet 131 can be the two long sides of the electrode sheet 131 opposite each other in the second direction or the two short sides opposite each other in the third direction. The first sidewall 111 can be the shell wall of the battery casing 11 arranged opposite to the two long sides in the second direction, or it can be the shell wall arranged opposite to the two short sides in the third direction.

[0051] like Figure 2 As shown, the electrode assembly 13 may also include a diaphragm 132, which may be reciprocated in a first direction, and an electrode sheet 131 may be disposed between two overlapping portions of the diaphragm 132 in the first direction.

[0052] like Figure 1 As shown, the temperature regulating plate 2 can be a flat plate structure. The temperature regulating plate 2 can be disposed at the third-direction end of the single cell 1 and in contact with the first sidewall 111 of the single cell 1 in the third-direction. In some other embodiments, the temperature regulating plate 2 can also be disposed at the second-direction end of the single cell 1 and in contact with the first sidewall 111 of the single cell 1 in the second direction.

[0053] It should be noted that the temperature regulating plate 2 has internal structures such as channels. Specifically, the temperature regulating plate 2 can be a liquid-cooled plate with internal cooling channels, which allow the temperature regulating medium to flow along the temperature regulating plate 2. The temperature regulating medium can be a liquid such as water or ethylene glycol. Since the temperature regulating plate 2 is in close contact with the first side wall 111, the heat on the first side wall 111 can exchange with the temperature regulating medium, thereby regulating the temperature of the single cell 1.

[0054] In the battery of this embodiment, the temperature regulating plate 2 is disposed on the periphery of the electrode sheet 131 and corresponds to the side edge of the electrode sheet 131. Compared with the case in the related art where the temperature regulating plate 2 is disposed on the wall of the single cell 1 parallel to the two planes of the electrode sheet 131 in the thickness direction, the thermal resistance of heat conduction along the extension direction of the electrode sheet 131 is much smaller than the thermal resistance of heat conduction between the two electrode sheets 131, thereby improving the heat exchange efficiency between the single cell 1 and the temperature regulating plate 2, and thus improving the overall heat dissipation performance and cooling effect of the battery.

[0055] Secondly, in related technologies, the heat generated by the middle electrode 131 needs to be transferred outward through multiple layers of electrode 131, which makes it more difficult for the heat of the middle electrode 131 to be dissipated compared to the outer electrode 131. In this invention, the temperature regulating plate 2 is set on the side of multiple electrode 131, so that the heat conduction path of each electrode 131 is similar, thereby making the heat dissipation effect of each electrode 131 basically consistent, and also improving the problem of heat accumulation in the middle of each single cell 1, further ensuring the overall heat dissipation performance of the battery.

[0056] In some embodiments, such as Figure 2 As shown, the electrode sheet 131 can be square. The electrode sheet 131 includes two first side edges 1311 arranged opposite each other along a second direction and two second side edges 1312 arranged opposite each other along a third direction. The two first side edges 1311 can be the two long sides of the electrode sheet 131 described above, and the two second side edges 1312 can be the two short sides of the electrode sheet 131 described above.

[0057] like Figure 1 and Figure 2As shown, the first sidewall 111 and the second side 1312 of the electrode plate 131 are arranged opposite each other in the third direction. The second direction is perpendicular to the first direction, and the third direction is perpendicular to the first and second directions. The temperature regulating plate 2 is in thermal contact with the first sidewall 111.

[0058] In some embodiments, the single cell 1 further includes electrode terminals 12, which are disposed on the sidewall of the battery casing 11 along a second direction or a third direction upward. For example, as Figure 2 As shown, electrode tabs can be led out from electrode sheet 131, and the electrode tabs are electrically connected to electrode terminal 12. The second direction can be the up-down direction, and the third direction can be the front-back direction. Electrode terminal 12 can be located on the top or bottom side of single cell 1. In some other embodiments, electrode terminal 12 can also be located on the front or rear side of single cell 1.

[0059] This allows the electrode terminal 12 to be located substantially within the extended plane of the electrode sheet 131, thereby facilitating the connection between the tab and the electrode terminal 12.

[0060] In some embodiments, the single cell 1 includes a thermally conductive medium 14 disposed between the first sidewall 111 and the electrode assembly 13. For example, as... Figure 3 As shown, the third direction can be left and right. The first sidewall 111 can be located on the left and / or right side of the electrode assembly 13. The thermally conductive medium 14 can be made of thermally conductive structural adhesive or other materials. A gap can be reserved between the first sidewall 111 and the electrode assembly 13. The thermally conductive medium 14 can fill the gap reserved between the first sidewall 111 and the electrode assembly 13.

[0061] The thermal conductive medium 14 can reduce the thermal resistance between the electrode assembly 13 and the first sidewall 111, thereby further improving the thermal conductivity of the single cell 1. This allows the first sidewall 111 to become the optimal heat dissipation surface of the single cell 1, which can facilitate the cooling design of the side of the single cell 1 and improve the overall cooling efficiency.

[0062] Secondly, the heat-conducting medium 14 can also be made of a material with a certain degree of elasticity, which can buffer the squeezing and vibration between the battery casing 11 and the electrode assembly 13.

[0063] In some embodiments, the thermal conductivity of the heat-conducting medium 14 is k1. Once the material of the heat-conducting medium 14 is determined, the thermal conductivity k1 of the heat-conducting medium 14 is also the thermal conductivity of the corresponding material.

[0064] like Figure 3As shown, the distance between the electrode assembly 13 and the first sidewall 111 is L1, which is also the width of the reserved gap between the electrode assembly 13 and the first sidewall 111. The area of ​​the first sidewall 111 is A1, which is the projected area of ​​the first sidewall 111 in the third direction, and L1 / (k1*A1)≤9.9K / W.

[0065] By limiting the thermal conductivity k1, the area A1 of the first sidewall 111, and the distance L1 to the range defined by the above inequality, the thermal conductivity k1, the area A1 of the first sidewall 111, and the distance L1 can be optimized. This avoids situations where the distance between the first sidewall 111 and the electrode assembly 13 is too far or the thermal conductivity is insufficient, resulting in poor heat dissipation. That is, if L1 / (k1*A1)>9.9K / W, the distance L1 between the electrode assembly 13 and the first sidewall 111 is too large, or the thermal conductivity k1 is too small, or the area of ​​the first sidewall 111 is too small, the side heat dissipation effect of the single cell 1 will be poor, thus failing to meet the requirement that the maximum battery temperature is <55℃ under normal temperature fast charging conditions.

[0066] In some embodiments, the thermal conductivity of the electrode assembly 13 in the third direction is k2, the thermal conductivity of the electrode assembly 13 in the second direction is k3, and the thermal conductivity of the electrode assembly 13 in the first direction is k4, and k2 > k4, k3 > k4.

[0067] For example, such as Figure 3 As shown, thermal conductivity k2 is the thermal conductivity of electrode assembly 13 in the length direction, and thermal conductivity k3 is the thermal conductivity of electrode assembly 13 in the vertical direction. Figure 4 As shown, the thermal conductivity k4 is the thermal conductivity of the electrode assembly 13 in the width direction. For the stacked electrode assembly 13, the thermal conductivity of the electrode assembly 13 in the length, height and width directions is anisotropic, where k1≈k2, but either the thermal conductivity k2 or the thermal conductivity k3 is greater than k4.

[0068] Since the first sidewall 111 is located on the side of the electrode assembly 13 in the second or third direction, good heat dissipation characteristics are fully guaranteed between the first sidewall 111 and the electrode assembly 13.

[0069] In some embodiments, such as Figure 5 As shown, there are multiple temperature control plates 2, each of which can be a long plate. Each temperature control plate 2 extends along a first direction, and the multiple temperature control plates 2 are arranged at intervals in a third direction.

[0070] like Figure 5As shown, multiple temperature regulating plates 2 can be provided with pipes 3 on the same side along the first direction. There are two pipes 3, namely an inlet pipe and a drain pipe. The inlet pipe and the drain pipe can be connected to each temperature regulating plate 2. The temperature regulating medium can be introduced into the multiple temperature regulating plates 2 through the inlet pipe, and then the temperature regulating medium in the multiple temperature regulating plates 2 can be discharged through the drain pipe, thereby realizing the circulation and transportation of the temperature regulating medium in the multiple temperature regulating plates 2.

[0071] Multiple individual battery cells 1 are arranged along the first direction between two adjacent temperature regulating plates 2. Specifically, during the assembly of multiple individual battery cells 1, the temperature regulating plate 2 can be assembled between two adjacent rows of battery cells 1, thereby filling the heat insulation gap between the two rows of battery cells 1 and improving the energy density of the battery.

[0072] For example, such as Figure 5 As shown, the multiple individual cells 1 can be arranged in a matrix, and the multiple individual cells 1 can be arranged in columns along a first direction and in rows along a third direction. Each column can include multiple individual cells 1 arranged at intervals along the first direction, and each row can include multiple individual cells 1 arranged at intervals along a third direction. Each column of individual cells 1 is located between two adjacent temperature regulating plates 2.

[0073] In some embodiments, such as Figure 3 and Figure 4 As shown, the battery case 11 includes a second sidewall 112 arranged opposite to the electrode sheet 131 in a first direction. The thermal resistance R1 between the electrode assembly 13 and the first sidewall 111 is not greater than the thermal resistance R2 between the electrode assembly 13 and the second sidewall 112. The battery case 11 has a third sidewall 113 perpendicular to the first sidewall 111 and the second sidewall 112. The thermal resistance R1 is not greater than the thermal resistance R3 between the electrode assembly 13 and the third sidewall 113 of the battery case 11.

[0074] Therefore, relative to the large surface and the bottom surface, where the large surface can be the aforementioned second sidewall 112 and the bottom surface can be the aforementioned third sidewall 113, the thermal resistance between the electrode assembly 13 and the first sidewall 111 of the battery case 11 is minimized, thereby ensuring a better cooling and heat dissipation effect through the smaller area of ​​the sidewall.

[0075] In some embodiments, the battery includes a casing 4, and there are multiple individual cells 1. The multiple individual cells 1 are all assembled inside the casing 4. The casing 4 is filled with a potting medium 5. The potting medium 5 is distributed between the casing 4 and the individual cells 1, and between two adjacent individual cells 1.

[0076] For example, such as Figure 6As shown, the outer casing 4 may include a bottom casing 42 and a top cover 41. The bottom casing 42 may be box-shaped, with an open top. The top cover 41 may be fixed to the top side of the bottom casing 42 by fasteners and seal the open top. Multiple individual battery cells 1 may be arranged in a matrix and may be assembled inside the bottom casing 42.

[0077] The potting medium 5 can be potting compound. After the top cover 41 is installed on the bottom shell 42, the potting medium 5 can be injected into the outer shell 4 through a dedicated filling hole. The potting medium 5 can fill various gaps inside the outer shell 4, for example, it can be located between the second sidewalls 112 of two individual cells 1, or it can be between the outer shell 4 and any individual cell 1. Of course, potting compound can also be filled into the outer shell 4 before the top cover 41 is installed on the bottom shell 42.

[0078] Because the potting compound has a low thermal conductivity, it can prevent the heat from being transferred from the single cell 1 to other single cells 1 or other components through the potting compound, thus achieving a better heat insulation effect and helping to suppress the spread of thermal runaway of a single cell 1.

[0079] Because the potting medium 5 has a certain degree of elasticity, the potting medium 5 can be compressed adaptively with the deformation of the single cell 1 after long-term use, thereby providing space for the deformation of the single cell 1 and absorbing the expansion displacement of the single cell 1 under different working conditions.

[0080] Secondly, the potting medium 5 can ensure good adhesion between the potting medium 5 and the individual battery 1 and other structural components when the individual battery 1 expands under different working conditions; even when the individual battery 1 rebounds after expansion, the potting medium 5 can still ensure good adhesion between it and the individual battery 1 and other structural components, thus ensuring the compactness of the overall structure.

[0081] Furthermore, compared to filling foam in related technologies, potting media can be directly potted, avoiding the complex process of bonding foam to individual cells, simplifying the overall assembly process, and improving assembly efficiency. Compared to filling foam, potting media has a better adhesion and bonding effect with individual cells, thus fully ensuring the structural compactness of the individual cell assembly.

[0082] In some embodiments, the battery casing 11 is provided with a protrusion, which is disposed between two individual cells 1 to form a gap between the two individual cells 1 for filling the potting medium 5.

[0083] For example, each battery case 11 can be integrally formed with a protrusion, which can be a convex structure, and the protrusion can directly fit and contact the side wall of another single battery 1. Due to the support of the protrusion, there is a certain gap between the side walls of the two single batteries 1. These gaps can be used to fill the potting medium 5, and the potting medium 5 can also achieve heat insulation between the two single batteries 1.

[0084] In some embodiments, the battery includes a battery module 6 disposed within a housing 4. The battery module 6 includes a plurality of individual cells 1 arranged along a first direction or orthogonal to the first direction. The thermal conductivity of the potting medium 5 is k5. Once the material of the potting medium 5 is determined, the thermal conductivity k5 is also the thermal conductivity of the determined material.

[0085] The distance between the battery module 6 and the side wall of the outer casing 4 is L2. For example, the bottom casing 42 can be a tray, and the side wall of the outer casing 4 can be regarded as the frame of the tray. In this case, the distance L2 can be regarded as the distance between the outermost single battery 1 in the battery module 6 and the frame of the tray.

[0086] The side surface area of ​​the side wall of the single cell 1 facing the outer casing 4 is A2. Specifically, the side surface area A2 is the area of ​​the side wall of the single cell 1 that is opposite to the outer casing 4 in the inward and outward directions. For example, if the second side wall 112 of the single cell 1 is arranged opposite to the outer casing 4, the side surface area A2 is the area of ​​the second side wall 112.

[0087] In some embodiments, the thermal conductivity k5, distance L2, and side surface area A2 satisfy the following relationship: 0.55K / W≤L2 / (k5*A2)≤217K / W.

[0088] In this embodiment, the selection of the thermal conductivity k5 is related to the distance and the side surface area and needs to satisfy a certain proportional relationship. Specifically, L2 / (k5*A2) is greater than or equal to 0.55 K / W. If L2 / (k5*A2) < 0.55 K / W, then, when the distance L2 and the side surface area A2 are constant, the value of the thermal conductivity k5 will be too large, resulting in poor thermal insulation of the potting medium 5. This leads to poor thermal insulation between different individual cells 1. For example, if one individual cell 1 triggers thermal runaway, its heat will affect other individual cells 1, causing a wider range of thermal runaway. On the other hand, a relatively large thermal conductivity k5 of the potting medium 5 also makes the individual cells 1 more susceptible to the influence of the external environment. For example, in low-temperature environments in winter, the low-temperature performance of the individual cells 1 will be affected, further reducing the operating performance of the individual cells 1 in low-temperature environments. Furthermore, L2 / (k5*A2) is less than or equal to 217 K / W. If L2 / (k5*A2)>217K / W, when the thermal conductivity k5 and the side area A2 are constant, the distance L2 between the outermost single cell 1 and the side tray edge will be large. This will result in a low volume utilization rate inside the battery, making the battery design unable to meet the design requirement of battery pack volume utilization rate ≥70%, and also resulting in a low energy density of the battery.

[0089] In some embodiments, the expansion force of a single battery cell 1 is F1. The battery casing 11 includes a second sidewall 112 arranged opposite to the electrode sheet 131 in a first direction. The second sidewall 112 can be considered as the large surface of the battery casing 11, and the area of ​​the second sidewall 112 is S1. The expansion stress of the single battery cell 1 is M1 = F1 / S1. It should be noted that the above-mentioned expansion force F1 is a variable force. This expansion force F1 can be considered as the internal expansion force generated by the accumulation of internal gas in the single battery cell 1 after long-term operation.

[0090] like Figure 5 As shown, the thickness of the potting medium 5 between the second sidewalls 112 of two adjacent single cells 1 is L3, and the maximum expansion displacement of the single cell 1 is α. The maximum expansion displacement α can be regarded as the displacement of the second sidewall 112 moving outward after the single cell 1 expands. At this time, the maximum compressive strain β of the potting medium 5 is α / L3.

[0091] Furthermore, when the compressive strain of the potting medium 5 is β, the corresponding compressive stress of the potting medium 5 is M2, where M1 ≥ M2. Therefore, the potting medium 5 can completely absorb the expansion of the individual cell 1, thus providing sufficient deformation leeway for the expansion and deformation of the individual cell 1.

[0092] In some embodiments, the maximum voltage of the battery is U1, which can be regarded as the output voltage of the battery. The insulation voltage of the potting medium 5 in the first direction is U2. The insulation voltage U2 is related to the thickness of the potting medium 5. When the thickness of the potting medium 5 in the first direction is greater, the insulation voltage U2 is also greater, and U2≥3.7U1.

[0093] Within the constraints of this inequality, there will be good insulation protection between individual cells 1 or between individual cells 1 and non-directly connected high-voltage components, avoiding the situation where insulation failure is likely to occur. For details, please refer to Table 1 below.

[0094] Table 1: Insulation Fault Status Table

[0095] Serial Number U1(V) U2(V) U2 / U1 Is there an insulation fault? 1 490 3300 6.7 No insulation faults occurred 2 870 3300 3.8 No insulation faults occurred 3 870 2500 2.8 Insulation fault occurred

[0096] In some embodiments, after the potting medium 5 has cured, the first-order free mode of the battery is ≥55Hz. This ensures that the battery will not experience structural failures under various mechanical conditions, such as random vibration and impact, thus guaranteeing the stability of its use and performance.

[0097] In some embodiments, the battery casing 11 includes a second sidewall 112 arranged opposite to the electrode sheet 131 in a first direction. The second sidewall 112 can be considered as the large surface of a single battery cell 1, such as... Figure 5 As shown, the gap width between the second sidewalls 112 of two adjacent single cells 1 is L4, and the capacity of the single cell 1 is Q1, 17.2Ah / mm≤Q1 / L4≤547.3Ah / mm.

[0098] If Q1 / L4 < 17.2 Ah / mm, then when the capacity Q1 of a single cell 1 is constant, the spacing between single cells 1 will be too large, resulting in a lower overall volume utilization rate of the battery pack. This fails to meet the design requirement that the battery pack volume utilization rate be ≥ 70%. Furthermore, it also results in a lower volumetric energy density of the single cell 1.

[0099] If Q1 / L4 > 547.3 Ah / mm, then, for a given capacity Q1 of a single cell 1, the spacing between cells 1 will be too small. When a single cell 1 experiences thermal runaway, it can easily trigger thermal runaway in adjacent cells 1, leading to widespread thermal runaway of cells 1 within the entire casing 4, thus reducing battery safety. For battery pack fires, explosions, and battery thermal runaway standards and testing methods, please refer to GB38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles," as detailed in Table 2.

[0100] Table 2: Battery Thermal Runaway Criteria and Volume Utilization Rate

[0101]

[0102]

[0103] In some embodiments, the temperature regulating plate 2 is provided with a plurality of medium channels for the flow of temperature regulating medium. The cross-sectional area of ​​the medium channel is S2, which is also the flow cross-sectional area of ​​each medium channel. The cross-sectional area of ​​the temperature regulating plate 2 perpendicular to its extension direction is S3. The cross-sectional area S3 can be regarded as the cross-sectional area of ​​the temperature regulating plate 2 orthogonal to the first direction, and 50% ≤ S2 / S3 ≤ 99%.

[0104] If S2 / S3 < 50%, the effective heat dissipation cross-sectional area of ​​the medium channel of the temperature regulating plate 2 is too low, which will result in insufficient heat dissipation capacity. This will also cause the cooling capacity and cooling rate of the single cell 1 to fail to meet the requirements of thermal management. Consequently, the maximum temperature of the single cell 1 under normal temperature fast charging conditions will exceed 55℃, which will not meet the corresponding usage requirements.

[0105] If S2 / S3 > 99%, the wall thickness of the temperature regulating plate 2 will be too thin, the structural strength of the temperature regulating plate 2 will decrease, and the manufacturing process of the temperature regulating plate 2 will become a bottleneck. Under vibration and impact conditions, the temperature regulating plate 2 is prone to breakage, cracking, deformation, etc. The vibration and impact conditions of the temperature regulating plate 2 can be referred to the test standard GB38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles", as shown in Table 3 below. The battery capacity in Table 3 is 185Ah, the energy is 97kWh, and the number of cells and the series-parallel relationship is 1P208S.

[0106] Table 3: Vibration and Shock Test Table for Temperature Control Plate

[0107]

[0108] In some embodiments, a chamfer R1 is provided between the walls of two adjacent channels in each medium channel, and 0.1mm≤R1≤5mm. This reduces the flow resistance of fluids such as temperature-regulating media in the medium channels, thereby improving the overall heat exchange efficiency and effect.

[0109] In some embodiments, the maximum voltage of the battery is U1, which can be regarded as the output voltage of the battery. The insulation voltage of the temperature regulating plate 2 is U3. The surface of the temperature regulating plate 2 can be pasted or sprayed with insulating material, or the temperature regulating plate 2 can be made of non-metallic composite material, so that the surface of the temperature regulating plate 2 has insulating properties. The insulation voltage U3 is the voltage value characterizing the insulation characteristics of the temperature regulating plate 2, and U3≥7.5U1.

[0110] If U3 < 7.5U1, the insulation capacity of the temperature regulating plate 2 will be low. Under special operating conditions, such as when the single cell 1 triggers thermal runaway, the insulation between the temperature regulating plate 2 and the single cell 1 may fail, which may lead to electrical safety risks such as short circuit and arcing in the battery, and trigger a wider range of thermal runaway.

[0111] The electrical equipment according to embodiments of the present invention is described below.

[0112] The electrical device in this embodiment of the invention includes a battery, which can be the battery described in any of the above embodiments. The electrical device can be a car, SUV, or other vehicle, or other electrical device that requires the installation of a battery.

[0113] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A battery, characterized in that, include: A single battery cell includes a battery casing and an electrode assembly disposed within the battery casing. The electrode assembly includes multiple electrode sheets stacked along a first direction, and at least two positive electrode sheets among the multiple electrode sheets are not continuously disposed. The first direction is the thickness direction of the electrode sheets. A temperature regulating plate is provided, which is in thermal contact with the first sidewall of the battery case corresponding to the side of the electrode sheet, and a temperature regulating medium is introduced into the temperature regulating plate to regulate the temperature of the individual battery cell.

2. The battery according to claim 1, characterized in that, The electrode sheet includes two first sidewalls arranged opposite each other along a second direction and two second sidewalls arranged opposite each other along a third direction. The first sidewall and the second sidewall of the electrode sheet are arranged opposite each other in the third direction. The second direction is perpendicular to the first direction, and the third direction is perpendicular to both the first and second directions. The temperature regulating plate is in thermal contact with the first sidewall.

3. The battery according to claim 2, characterized in that, The single cell also includes electrode terminals, which are disposed on the sidewall of the battery casing along the second direction or the third direction.

4. The battery according to claim 2, characterized in that, It includes a thermally conductive medium disposed between the first sidewall and the electrode assembly.

5. The battery according to claim 4, characterized in that, The thermal conductivity of the heat-conducting medium is k1, the distance between the electrode assembly and the first sidewall is L1, the area of ​​the first sidewall is A1, and L1 / (k1*A1)≤9.9K / W.

6. The battery according to claim 2, characterized in that, The thermal conductivity of the electrode assembly in the third direction is k2, the thermal conductivity of the electrode assembly in the second direction is k3, and the thermal conductivity of the electrode assembly in the first direction is k4, where k2 > k4 and k3 > k4.

7. The battery according to claim 2, characterized in that, There are multiple temperature regulating plates, each of which extends along the first direction. The multiple temperature regulating plates are arranged at intervals in the third direction, and multiple individual batteries arranged along the first direction are provided between two adjacent temperature regulating plates.

8. The battery according to claim 1, characterized in that, The battery casing includes a second sidewall arranged opposite to the electrode sheet in the first direction, and the thermal resistance R1 between the electrode assembly and the first sidewall is not greater than the thermal resistance R2 between the electrode assembly and the second sidewall. The battery casing has a third sidewall perpendicular to the first sidewall and the second sidewall, and the thermal resistance R1 is not greater than the thermal resistance R3 between the electrode assembly and the third sidewall of the battery casing.

9. The battery according to any one of claims 1-8, characterized in that, The device includes a casing, and there are multiple individual cells. All of the individual cells are assembled inside the casing. The casing is filled with a potting medium, and the potting medium is distributed between the casing and the individual cells, as well as between two adjacent individual cells.

10. The battery according to claim 9, characterized in that, The battery casing has a protrusion, which is disposed between two individual cells to form a gap between the two individual cells for filling the potting medium.

11. The battery according to claim 9, characterized in that, The device includes a battery module disposed within the housing. The battery module comprises multiple individual cells arranged along the first direction or in a third direction orthogonal to the first direction. The thermal conductivity of the potting medium is k5. The distance between the battery module and the sidewall of the housing is L2. The lateral surface area of ​​the individual cell facing the sidewall of the housing is A2. 0.55K / W≤L2 / (k5*A2)≤217K / W.

12. The battery according to claim 9, characterized in that, The expansion force of the single cell is F1, the battery casing includes a second sidewall arranged opposite to the electrode sheet in the first direction, the area of ​​the second sidewall is S1, and the expansion stress of the single cell is M1 = F1 / S1. The thickness of the potting medium between the second sidewalls of two adjacent single cells is L3, the maximum expansion displacement of the single cell is α, and the maximum compressive strain of the potting medium is β=α / L3; Furthermore, when the compressive strain of the potting medium is β, the compressive stress corresponding to the potting medium is M2, and M1≥M2.

13. The battery according to claim 9, characterized in that, The maximum voltage of the battery is U1, and the insulation voltage of the potting medium in the first direction is U2, where U2 ≥ 3.7U1; And / or, the first-order free mode of the battery is ≥55Hz.

14. The battery according to claim 9, characterized in that, The battery casing includes a second sidewall arranged opposite to the electrode sheet in the first direction, the gap width between the second sidewalls of two adjacent individual cells is L4, the capacity of the individual cell is Q1, 17.2Ah / mm≤Q1 / L4≤547.3Ah / mm.

15. The battery according to any one of claims 1-8, characterized in that, The temperature regulating plate has multiple medium channels for the flow of temperature regulating medium. The cross-sectional area of ​​the medium channel is S2, and the cross-sectional area of ​​the temperature regulating plate perpendicular to its extension direction is S3, where 50% ≤ S2 / S3 ≤ 99%.

16. The battery according to claim 15, characterized in that, Each of the media channels has a chamfer R1 between two adjacent channel walls, and 0.1mm≤R1≤5mm; And / or, the maximum voltage of the battery is U1, the insulation voltage of the temperature regulating plate is U3, and U3 ≥ 7.5U1.

17. An electrical appliance, characterized in that, Includes the battery as described in any one of claims 1-16 above.

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