Pole piece, battery cell assembly, single battery, battery device and electric device

Abstract

This disclosure provides an electrode, a cell assembly including the electrode, a single cell including the cell assembly, a battery device including the single cell, and an electrical device including the battery device or the single cell. The electrode includes a current collector and a material layer disposed on at least one side surface of the current collector along a first direction. The material layer includes a first material layer and a second material layer. The first material layer includes a first material, and the second material layer includes a second material. The thermal conductivity of the first material is greater than that of the second material. Along a second direction, at least one end of the electrode has a tab. The first material layer is located in the end region of the current collector near the tab. Along the second direction, the second material layer is located on the side of the first material layer away from the tab. The first and second directions intersect, enabling rapid heat transfer from the end of the cell near the tab to the end away from the tab. This reduces the temperature difference and the maximum temperature while increasing the minimum temperature of the cell, thereby improving the fast-charging performance and lifespan of the cell.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, specifically to an electrode, a cell assembly including the electrode, a single cell including the cell assembly, a battery device including the single cell, and an electrical device including the battery device or the single cell. Background Technology

[0002] Currently, due to uneven current distribution during battery charging, batteries typically exhibit a higher current density near the tab and a lower current density further away from the tab. This results in a significant temperature difference between the areas near and far from the tab, causing an imbalance in heat distribution. This uneven heat distribution not only affects the battery's fast charging performance but may also accelerate battery aging and shorten its cycle life.

[0003] To address this issue, existing technologies often employ external thermal management methods, such as air cooling, liquid cooling, or phase change materials, to achieve uniform cell temperature. However, these methods are typically complex in structure, expensive, and offer limited optimization of the internal heat conduction path of the battery, making it difficult to fundamentally improve the uneven heat distribution within the cell. Utility Model Content

[0004] In order to overcome the above-mentioned technical problems, this disclosure provides an electrode, a cell assembly including the electrode, a single cell including the cell assembly, a battery device including the single cell, and an electrical device including the battery device or the single cell.

[0005] The first objective of this disclosure is to provide an electrode, comprising a current collector and a material layer disposed on at least one side surface of the current collector along a first direction, the material layer comprising a first material layer and a second material layer, the first material layer comprising a first material and the second material layer comprising a second material, the thermal conductivity of the first material being greater than that of the second material; along a second direction, at least one end of the electrode is provided with an electrode tab, the first material layer being located in the end region of the current collector near the electrode tab, and along the second direction, the second material layer being located on the side of the first material layer away from the electrode tab, the first direction and the second direction intersecting.

[0006] As an alternative embodiment of this disclosure, the electrode has tabs at both ends along the second direction, and the number of first material layers is at least two, with at least two first material layers located on opposite sides of the second material layer along the second direction.

[0007] As an alternative embodiment of this disclosure, at least two first material layers are symmetrically distributed on opposite sides of the second material layer along the second direction.

[0008] As an alternative embodiment of this disclosure, the length of the second material layer along the second direction accounts for a proportion greater than 0 and less than 2 / 5.

[0009] As an alternative to this disclosure, the thermal conductivity of the first material is 217 W / (m·K)-5300 W / (m·K), and / or the thermal conductivity of the second material is 1 W / (m·K)-217 W / (m·K).

[0010] As an alternative to this disclosure, the first material is graphene, and / or the second material is carbon nanotubes.

[0011] As an alternative embodiment of this disclosure, the electrode also includes a dressing layer disposed on the surface of the material layer away from the current collector.

[0012] A second objective of this disclosure is to provide a battery cell assembly, comprising a plurality of positive electrode plates and a plurality of negative electrode plates, wherein at least one of the plurality of positive electrode plates is an electrode plate provided in this disclosure, and / or at least one of the plurality of negative electrode plates is an electrode plate provided in this disclosure, wherein each positive electrode plate and each negative electrode plate are alternately stacked along a first direction to form a battery cell assembly.

[0013] As an alternative embodiment of this disclosure, along the second direction, each positive electrode has a positive tab at both ends, and / or each negative electrode has a negative tab at both ends.

[0014] As an alternative embodiment of this disclosure, the cell assembly further includes multiple separators, each separator being disposed between each pair of adjacent positive and negative electrode plates, with all positive electrode plates, all negative electrode plates, and all separators being alternately stacked along a first direction.

[0015] As an alternative embodiment of this disclosure, the battery cell assembly has a first side and a second side disposed opposite to each other along a third direction. The battery cell assembly also includes at least one side plate, which is connected to at least one of the first side and the second side. The third direction intersects the first direction and the second direction in pairs.

[0016] As an alternative to this disclosure, a side panel adhesive is provided on the side of the side panel away from the cell assembly, and the side panel adhesive is used to bond and fix the side panel to the cell assembly.

[0017] A third object of this disclosure is to provide a single-cell battery, including a housing and a cell assembly provided in this disclosure, the cell assembly being housed within the housing.

[0018] As an alternative embodiment of this disclosure, the battery cell assembly includes multiple positive electrode plates and multiple negative electrode plates. Each positive electrode plate has a positive tab at both ends, and each negative electrode plate has a negative tab at both ends. The housing has a first cover plate and a second cover plate disposed opposite to each other. The first cover plate has a first positive electrode post and a first negative electrode post, and the second cover plate has a second positive electrode post and a second negative electrode post. The first positive electrode post and the second positive electrode post are both electrically connected to the positive tab, and the first negative electrode post and the second negative electrode post are both electrically connected to the negative tab.

[0019] As an alternative to this disclosure, the first cover plate is provided with an explosion-proof valve, and / or the second cover plate is provided with an injection hole.

[0020] As an alternative solution disclosed herein, an insulating film is provided between the housing and the cell assembly, and the insulating film covers the circumferential side of the cell assembly.

[0021] As an alternative to this disclosure, along the second direction, a first side spacer is provided between the first cover plate and the cell assembly, and / or, a second side spacer is provided between the second cover plate and the cell assembly.

[0022] A fourth object of this disclosure is to provide a battery device including the single cell provided in this disclosure.

[0023] A fifth object of this disclosure is to provide an electrical device that includes a battery device or a single battery cell provided in this disclosure.

[0024] This disclosure involves placing a first material layer on the end region of the current collector near the tab, and placing a second material layer on the side of the first material layer away from the tab. The thermal conductivity of the first material is greater than that of the second material, thereby enabling rapid heat transfer from the end of the cell near the tab to the end away from the tab. This reduces the temperature difference and the maximum temperature while increasing the minimum temperature of the cell, thus improving the fast charging performance and lifespan of the cell.

[0025] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0026] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0027] Figure 1 This is a schematic diagram of the structure of an electrode sheet provided according to one embodiment of the present disclosure.

[0028] Figure 2 This is a schematic diagram of the structure of an electrode sheet provided according to one embodiment of the present disclosure.

[0029] Figure 3 This is a schematic diagram of the structure of an electrode sheet provided according to one embodiment of the present disclosure.

[0030] Figure 4 This is a partial structural schematic diagram of a battery cell assembly provided according to one embodiment of the present disclosure.

[0031] Figure 5 This is a schematic diagram of the structure of a battery cell assembly provided according to one embodiment of the present disclosure.

[0032] Figure 6 This is a schematic diagram of the structure of a single cell provided according to one embodiment of the present disclosure.

[0033] Explanation of reference numerals in the attached figures:

[0034] -10: Extreme Film 10

[0035] -11: Positive electrode 11

[0036] -12: Negative electrode 12

[0037] -100: Current collector 100

[0038] -110: Material layer 110

[0039] -111: First material layer 111

[0040] -112: Second material layer 112

[0041] -120: Dressing layer 120

[0042] -200: Polar Ear 200

[0043] -201: Positive electrode 201

[0044] -202: Negative electrode ear 202

[0045] -300: Cell assembly 300

[0046] -301: First side view 301

[0047] -302: Second side 302

[0048] -310: Side panel 310

[0049] -320: Side panel adhesive 320

[0050] -400: Diaphragm 400

[0051] -500: 500 per cell

[0052] -510: Housing 510

[0053] -511: First cover plate 511

[0054] -512: Second cover plate 512

[0055] -521: First positive terminal 521

[0056] -522: First negative terminal 522

[0057] -531: Second positive terminal 531

[0058] -532: Second negative electrode post 532

[0059] -541: Explosion-proof valve 541

[0060] -542: Injection port 542

[0061] -600: Insulating film 600

[0062] -551: First side spacer 551

[0063] -552: Second side spacer 552

[0064] -X: First direction

[0065] -Y: Second direction

[0066] -Z: Third-party direction Detailed Implementation

[0067] Embodiments of this disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this disclosure, and should not be construed as limiting this disclosure.

[0068] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this disclosure and 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, and therefore should not be construed as a limitation of this disclosure. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0069] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" 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 between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0070] like Figures 1 to 6 As shown, this disclosure provides an electrode 10, a cell assembly 300 including the electrode 10, a single cell 500 including the cell assembly 300, a battery device including the single cell 500, and a power-consuming device including the battery device or the single cell 500. Multiple single cells 500 are arranged in the battery device in series or parallel. Furthermore, besides the field of battery devices, the various technical solutions provided in this disclosure can also be widely applied to other battery fields.

[0071] To clarify the technical solution of this disclosure, the disclosure is illustrated through the following specific embodiments. However, it is not limited to these specific embodiments, and the features in each embodiment can be arbitrarily combined or replaced.

[0072] In one optional embodiment, the electrode 10 provided in this disclosure includes a current collector 100 and a material layer 110 disposed on at least one side surface of the current collector 100 along a first direction. The material layer 110 includes a first material layer 111 and a second material layer 112. The first material layer 111 includes a first material, and the second material layer 112 includes a second material. The thermal conductivity of the first material is greater than that of the second material. Along a second direction, at least one end of the electrode 10 is provided with a tab 200. The first material layer 111 is located in the end region of the current collector 100 near the tab 200. Along the second direction, the second material layer 112 is located on the side of the first material layer 111 away from the tab 200. The first direction and the second direction intersect. This solution, through gradient thermal conductive material design, achieves a 2-3 times increase in the internal heat flow rate of the battery cell, a 7°C reduction in the maximum temperature, a 5°C reduction in the maximum temperature difference, and a 1.5-minute reduction in fast charging time.

[0073] In specific implementation methods, such as Figure 1 , Figure 2As shown, by coating different thermal conductivity material layers 110 on the surface of the current collector 100 in different regions, the problem of uneven heat distribution between the end near the tab 200 and the end away from the tab 200 during battery charging is solved. The current collector 100 can be copper foil or aluminum foil. The material layers 110 are disposed on at least one side surface along the first direction (the thickness direction of the electrode 10). The first material layer 111 is made of a high thermal conductivity material (such as graphene, with a thermal conductivity of 217 W / (m·K)-5300 W / (m·K)) and covers the end region of the current collector 100 near the tab 200, ensuring that heat is quickly transferred from the end near the tab 200 to the end away from the tab 200. The second material layer 112 is made of a low thermal conductivity material (such as carbon nanotubes with an orientation degree >85%, with a thermal conductivity of 1 W / (m·K)-217 W / (m·K)) and covers the side of the first material layer 111 away from the tab 200, forming a thermal resistance to slow down the outward loss of heat. The first direction is perpendicular to the second direction (the length direction of the electrode 10), and the material layer 110 is coated in a gradient manner through spraying, printing, or lamination processes. This design reduces the maximum temperature of the battery cell by 7°C, the maximum temperature difference by 5°C, and the fast charging time by 1.5 minutes.

[0074] In one optional implementation, the electrode 10 has tabs 200 at both ends along the second direction, and at least two first material layers 111 are located on opposite sides of the second material layer 112 along the second direction. This solution, through the distribution of high thermal conductivity layers on both sides, can simultaneously guide the heat from the two tab ends 200 to the middle region, avoiding local overheating caused by unilateral heat conduction.

[0075] In specific implementation methods, such as Figure 2 As shown, when tabs 200 are provided at both ends of the electrode 10, the first material layer 111 is located in the two end regions, and the middle region is covered by the second material layer 112. The first material layer 111 uses a high thermal conductivity material (such as graphene, with a thermal conductivity of 217 W / (m·K)-5300 W / (m·K)), and the second material layer 112 uses a low thermal conductivity material (such as carbon nanotubes with an orientation degree >85%, with a thermal conductivity of 1 W / (m·K)-217 W / (m·K)). This design is suitable for high-power battery modules and ensures a balanced overall heat distribution in the cell.

[0076] In one optional implementation, at least two first material layers 111 are symmetrically distributed on opposite sides of the second material layer 112 along the second direction. The symmetrical design can balance the heat conduction paths on both sides and avoid uneven heat flow caused by the offset of the material layer 110.

[0077] In specific implementation methods, such as Figure 2As shown, at least two first material layers 111 are symmetrically distributed on opposite sides of the second material layer 112 along a second direction, which is the length direction of the electrode 10. The first material layer 111 is made of a high thermal conductivity material (such as graphene, with a thermal conductivity of 217 W / (m·K)-5300 W / (m·K)), and the second material layer 112 is made of a low thermal conductivity material (such as carbon nanotubes with an orientation degree >85%, with a thermal conductivity of 1 W / (m·K)-217 W / (m·K)). For example, if the electrode 10 is 200mm long, the second material layer 112 occupies the central 40mm area, and the high thermal conductivity material layer 110 is coated on each of the 80mm areas on both sides. During manufacturing, symmetrical coating can be achieved by template printing or laser cutting to ensure process accuracy. The symmetrical design can balance the heat conduction path on both sides and avoid uneven heat flow caused by the offset of the material layer 110. In this way, the high thermal conductivity areas at both ends can transfer heat to the middle more quickly, while the low thermal conductivity area in the middle slows down the outward loss of heat, thereby balancing the overall temperature.

[0078] In one optional implementation, the length of the second material layer 112 along the second direction is greater than 0 and less than 2 / 5. If the length of the second material layer 112 is 0, there is no thermal resistance effect; if the length is too large, it may suppress the overall heat conduction efficiency.

[0079] In specific implementation methods, such as Figure 1 , Figure 3 As shown, the length of the second material layer 112 along the second direction accounts for a proportion greater than 0 and less than 2 / 5. Preferably, the length of the second material layer 112 along the second direction accounts for 1 / 5. If the proportion is too small (e.g., <1 / 5), the thermal resistance effect is insufficient; if the proportion is too large (e.g., >1 / 5), it may inhibit the overall heat conduction efficiency. Experimental verification shows that when the proportion of the second material layer 112 is 1 / 5, the maximum temperature difference of the battery cell can be reduced by 5℃, while maintaining a 2-3% increase in heat flow rate.

[0080] In one optional implementation, the thermal conductivity of the first material is 217 W / (m·K)-5300 W / (m·K), and / or the thermal conductivity of the second material is 1 W / (m·K)-217 W / (m·K). Through the material gradient design, the high thermal conductivity layer quickly transfers heat from the tab 200 end, while the low thermal conductivity layer forms thermal resistance to suppress heat loss to the external environment.

[0081] In specific implementation methods, such as Figure 1 , Figure 2 , Figure 3As shown, the thermal conductivity of the first material is 217 W / (m·K)-5300 W / (m·K), and / or the thermal conductivity of the second material is 1 W / (m·K)-217 W / (m·K). The first material is preferably graphene, which has a thermal conductivity as high as 5300 W / (m·K) and excellent thermal stability. The second material is preferably carbon nanotubes with an orientation degree >85% and a thermal conductivity of 1 W / (m·K)-217 W / (m·K). Through material gradient design, the high thermal conductivity layer quickly transfers heat to the tab 200 end, while the low thermal conductivity layer forms thermal resistance to suppress heat loss to the external environment. For example, the length of the electrode 10 is 200 mm. A graphene layer (thickness 50 μm) is coated within an 80 mm range at the tab 200 end, and a carbon nanotube layer (thickness 30 μm) is coated in the middle 40 mm region, thereby increasing the heat flow rate by 2.5 times.

[0082] In one alternative implementation, the first material is graphene, and / or the second material is carbon nanotubes. The difference in thermal conductivity between graphene and carbon nanotubes can create a significant thermal gradient, thereby improving the temperature control effect.

[0083] In specific implementation methods, such as Figure 1 , Figure 2 , Figure 3 As shown, the first material is graphene, and / or the second material is carbon nanotubes. The graphene layer is prepared by chemical vapor deposition (CVD) or mechanical exfoliation, exhibiting high thermal conductivity and a low coefficient of thermal expansion. The carbon nanotube layer is prepared by directional growth, with an orientation degree >85% to ensure consistent thermal conductivity. Both materials must be firmly bonded to the surface of the current collector 100 using an adhesive (such as polyimide) to prevent delamination during repeated use. The difference in thermal conductivity between graphene and carbon nanotubes can create a significant thermal gradient, improving temperature control. The first material can also be diamond or silicon carbide, and the second material can also be a ceramic material, such as alumina.

[0084] In an optional implementation, the electrode 10 further includes a dressing layer 120 disposed on the surface of the material layer 110 away from the current collector 100. The presence of the dressing layer 120 does not affect the thermal conductivity of the material layer 110, while ensuring the integrity of the electrode function.

[0085] In specific implementation methods, such as Figure 1 , Figure 2 , Figure 3As shown, the electrode 10 also includes a coating layer 120, which is disposed on the surface of the material layer 110 away from the current collector 100. The coating layer 120 is a coating layer of electrode active material (such as lithium cobalt oxide or graphite), which is uniformly covered on the surface of the material layer 110 by a coating machine. The thickness of the coating layer 120 is 50-200μm and needs to be compatible with the material layer 110 to avoid cracking due to differences in thermal expansion. For example, lithium cobalt oxide slurry is coated on the surface of the graphene layer and a dense structure is formed by drying and rolling processes. The presence of the coating layer 120 does not affect the thermal conductivity of the material layer 110, while ensuring the integrity of the electrode function.

[0086] In one optional implementation, the battery cell assembly 300 provided in this disclosure includes a plurality of positive electrode plates 11 and a plurality of negative electrode plates 12, at least one of the plurality of positive electrode plates 11 being an electrode plate 10 provided in this disclosure, and / or at least one of the plurality of negative electrode plates 12 being an electrode plate 10 provided in this disclosure. Each positive electrode plate 11 and each negative electrode plate 12 are alternately stacked along a first direction to form the battery cell assembly 300. This design is suitable for high energy density battery modules and improves overall thermal management efficiency.

[0087] In specific implementation methods, such as Figure 4 , Figure 5 As shown, the battery cell assembly 300 includes multiple positive electrode plates 11 and multiple negative electrode plates 12, wherein at least one positive electrode plate 11 or negative electrode plate 12 is the aforementioned electrode plate 10 structure. Each positive electrode plate 11 and each negative electrode plate 12 are alternately stacked along a first direction to form the battery cell assembly 300. During stacking, it is necessary to ensure that the high thermal conductivity layer and the low thermal conductivity layer form a heat conduction path between adjacent electrode plates 10. For example, the high thermal conductivity layer of the positive electrode plate 11 is in contact with the low thermal conductivity layer of the negative electrode plate 12 to optimize the heat flow direction. This design is suitable for high energy density battery modules and improves the overall thermal management efficiency.

[0088] In one alternative implementation, along the second direction, each positive electrode 11 is provided with a positive tab 201 at both ends, and / or each negative electrode 12 is provided with a negative tab 202 at both ends. The tabs 200 are connected to the electrode body 10 by welding or laser cutting to ensure that the current conduction path is short and uniform.

[0089] In specific implementation methods, such as Figure 4 , Figure 5As shown, along the second direction, each positive electrode 11 has a positive tab 201 at both ends, and / or each negative electrode 12 has a negative tab 202 at both ends. The tabs 200 are connected to the electrode body 10 by welding or laser cutting to ensure that the current conduction path is short and uniform. The double tab 200 design works with the gradient material layer 110 of the electrode 10 to guide the heat from the two tab ends 200 to the middle at the same time, reducing local temperature rise. For example, on a 200mm long electrode 10, the tabs 200 are located at 5mm on both sides, and the high thermal conductivity layer covers an 80mm area at the tab ends 200.

[0090] In an optional implementation, the cell assembly 300 further includes a plurality of separators 400, each separator 400 being disposed between each pair of adjacent positive electrode plates 11 and negative electrode plates 12, with all positive electrode plates 11, all negative electrode plates 12 and all separators 400 being alternately stacked along a first direction, and the separators 400 can ensure electrolyte permeation while isolating the positive and negative electrodes.

[0091] In specific implementation methods, such as Figure 4 , Figure 5 As shown, the battery cell assembly 300 also includes multiple separators 400. Each separator 400 is disposed between each pair of adjacent positive electrode plates 11 and negative electrode plates 12. All positive electrode plates 11, negative electrode plates 12 and separators 400 are alternately stacked along the first direction. The separator 400 is a porous membrane of polyethylene or polypropylene with a thickness of 10-30 μm and a porosity of 40-60%, which ensures electrolyte penetration while isolating the positive and negative electrodes. The heat conduction path of the gradient material layer 110 must avoid the separator 400 area to prevent the separator 400 from deforming due to high temperature. For example, a 5 mm area without separator 400 is left between the high thermal conductivity layers of the positive and negative electrode plates 12 to ensure smooth heat flow.

[0092] In one optional embodiment, the cell assembly 300 has a first side 301 and a second side 302 disposed opposite each other along a third direction. The cell assembly 300 also includes at least one side plate 310, which is connected to at least one of the first side 301 and the second side 302. The third direction intersects the first direction and the second direction in pairs. The side plate 310 extends along the third direction (perpendicular to the first and second directions) to enhance structural strength and assist in heat conduction.

[0093] In specific implementation methods, such as Figure 4 , Figure 5As shown, the battery cell assembly 300 has a first side 301 and a second side 302 disposed opposite to each other along a third direction. The battery cell assembly 300 also includes at least one side plate 310, which is connected to at least one of the first side 301 and the second side 302. The third direction intersects the first direction and the second direction in pairs. The side plate 310 is a metal (such as aluminum) or ceramic plate and is fixed to the side of the battery cell assembly 300 by adhesive or welding. The side plate 310 extends along the third direction (perpendicular to the first and second directions) to enhance structural strength and assist in heat conduction. For example, an aluminum side plate 310 is installed on the long side (first direction) of the battery cell assembly 300. The side plate 310 is in contact with a high thermal conductivity layer to further guide heat to be transferred to the external heat dissipation channel.

[0094] In one optional implementation, a side panel adhesive 320 is provided on the side of the side panel 310 away from the cell assembly 300. The side panel adhesive 320 is used to bond and fix the side panel 310 to the cell assembly 300. The adhesive is bonded to the side panel 310 and the cell assembly 300 through hot pressing or UV curing process to ensure that the side panel 310 and the cell assembly 300 are in close contact.

[0095] In specific implementation methods, such as Figure 4 , Figure 5 As shown, a side panel adhesive 320 is provided on the side of the side panel 310 away from the cell assembly 300. The side panel adhesive 320 is used to bond and fix the side panel 310 to the cell assembly 300. The side panel adhesive 320 is a polyurethane or epoxy resin tape with a thickness of 0.1-0.5 mm and an adhesion strength ≥10 N / cm. 2 The adhesive is applied to bond the side plate 310 to the battery cell assembly 300 through hot pressing or UV curing process, ensuring that the side plate 310 and the battery cell assembly 300 are in close contact. For example, polyurethane adhesive is applied to the contact surface between the side plate 310 and the battery cell assembly 300, and after curing, a 0.2mm thick adhesive layer is formed, which both fixes the structure and reduces thermal resistance.

[0096] In one optional implementation, the single-cell battery 500 provided in this disclosure includes a housing 510 and a cell assembly 300 provided in this disclosure, wherein the cell assembly 300 is housed within the housing 510.

[0097] In specific implementation methods, such as Figure 6As shown, the single-cell battery 500 provided in this disclosure includes a housing 510 and the aforementioned cell assembly 300. The cell assembly 300 is housed within the housing 510, which is an aluminum or steel housing with an insulating gasket inside. The cell assembly 300 is fixed by snaps or adhesive. The top of the housing 510 has an injection hole 542 and an exhaust valve, and the bottom has an insulating film 600 covering the sides of the cell assembly 300. The heat conduction path of the gradient material layer 110 needs to be aligned with the heat dissipation structure (such as fins or flow channels) of the housing 510 to ensure efficient heat dissipation. For example, heat dissipation fins are provided at the bottom of the housing 510 to contact the high thermal conductivity layer of the cell assembly 300, thereby improving the overall thermal management efficiency.

[0098] In one optional embodiment, the battery cell assembly 300 includes a plurality of positive electrode plates 11 and a plurality of negative electrode plates 12. Each positive electrode plate 11 has a positive electrode tab 201 at both ends, and each negative electrode plate 12 has a negative electrode tab 202 at both ends. The housing 510 has a first cover plate 511 and a second cover plate 512 disposed opposite to each other. The first cover plate 511 has a first positive electrode post 521 and a first negative electrode post 522, and the second cover plate 512 has a second positive electrode post 531 and a second negative electrode post 522. 32. The first positive terminal 521 and the second positive terminal 531 are both electrically connected to the positive terminal tab 201, and the first negative terminal 522 and the second negative terminal 532 are both electrically connected to the negative terminal tab 202. The two terminals 200 of the positive electrode 11 are welded to the first positive terminal 521 and the second positive terminal 531 respectively, and the two terminals 200 of the negative electrode 12 are welded to the first negative terminal 522 and the second negative terminal 532 respectively, forming a parallel current conduction path, reducing internal resistance and improving fast charging performance.

[0099] In specific implementation methods, such as Figure 6 As shown, the battery cell assembly 300 includes multiple positive electrode plates 11 and multiple negative electrode plates 12. Each positive electrode plate 11 has a positive electrode tab 201 at both ends, and each negative electrode plate 12 has a negative electrode tab 202 at both ends. The housing 510 has a first cover plate 511 and a second cover plate 512 disposed opposite to each other. The first cover plate 511 has a first positive electrode post 521 and a first negative electrode post 522, and the second cover plate 512 has a second positive electrode post 531 and a second negative electrode post 532. The first positive electrode post 521 and the second positive electrode post 531 are both electrically connected to the positive electrode tab 201. Both negative terminal 522 and the second negative terminal 532 are electrically connected to the negative terminal tab 202. The positive and negative electrode plates 12 designed with dual terminals 200 are connected to the cover plate through the terminals. The terminals are made of copper or nickel alloy and are fixed by ultrasonic welding or laser welding. The first cover plate 511 and the second cover plate 512 are located at the top and bottom of the housing 510, respectively. The terminals penetrate the cover plate and are welded to the terminals 200. For example, the terminals 200 at both ends of the positive terminal plate 11 are welded to the first positive terminal 521 and the second positive terminal 531, respectively, to form a parallel current conduction path, reduce internal resistance and improve fast charging performance.

[0100] In one alternative implementation, the first cover plate 511 is provided with an explosion-proof valve 541, and / or the second cover plate 512 is provided with an injection hole 542. The explosion-proof valve 541 ensures the safety of the battery when the internal pressure rises abnormally, preventing explosion or severe damage, and the injection hole 542 ensures the injection and sealing of electrolyte.

[0101] In specific implementation methods, such as Figure 6 As shown, the first cover plate 511 is provided with an explosion-proof valve 541, and / or the second cover plate 512 is provided with an injection hole 542. The explosion-proof valve 541 is a pressure-sensitive diaphragm that automatically opens to release air when the internal pressure is >500kPa. The injection hole 542 is sealed with sealing glue and is used to inject electrolyte. The explosion-proof valve 541 is arranged at a distance from the electrode post to avoid the diaphragm performance being affected by the welding heat of the electrode post. For example, on the first cover plate 511, the explosion-proof valve 541 is located 5mm outside the electrode post to ensure a safe air release path.

[0102] In one optional implementation, an insulating film 600 is provided between the housing 510 and the cell assembly 300. The insulating film 600 covers the circumferential side of the cell assembly 300 to prevent short circuit between the cell and the housing 510, and at the same time reduce interference in the heat conduction path.

[0103] In specific implementation methods, such as Figure 6 As shown, an insulating film 600 is provided between the housing 510 and the cell assembly 300. The insulating film 600 wraps around the circumferential side of the cell assembly 300. The insulating film 600 is a polyimide or polyester film with a thickness of 5-20μm. It is fixed to the inner wall of the housing 510 by hot pressing or bonding. The insulating film 600 wraps around the circumferential side of the cell assembly 300 to prevent short circuit between the cell and the housing 510, and at the same time reduce interference in the heat conduction path. For example, a 0.5mm gap is left between the insulating film 600 and the high thermal conductivity layer to avoid the film from cracking due to thermal expansion differences.

[0104] In one alternative implementation, along the second direction, a first side spacer 551 is provided between the first cover plate 511 and the cell assembly 300, and / or a second side spacer 552 is provided between the second cover plate 512 and the cell assembly 300. The side spacers are used to seal the gap between the cover plate and the cell assembly 300 to prevent electrolyte leakage and reduce interference in the heat conduction path.

[0105] In specific implementation methods, such as Figure 6As shown, along the second direction, a first side spacer 551 is provided between the first cover plate 511 and the cell assembly 300, and / or a second side spacer 552 is provided between the second cover plate 512 and the cell assembly 300. The side spacer is a rubber or silicone ring with a thickness of 2-5mm, used to seal the gap between the cover plate and the cell assembly 300. The side spacer is arranged along the second direction (the length direction of the electrode 10) to prevent electrolyte leakage and reduce interference in the heat conduction path. For example, a silicone side spacer is provided between the first cover plate 511 and the cell assembly 300, with a width matching the width of the electrode 10, to ensure sealing and thermal management effect.

[0106] In addition, various embodiments of this disclosure also provide a battery device using the single cell 500, an electrical device using the battery device, or an electrical device using the single cell 500.

[0107] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0108] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0109] Similarly, it should be understood that, in order to streamline this application and aid in understanding one or more of the various aspects of the invention, features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, the inventive point lies in solving the corresponding technical problem with fewer features than all of those in a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0110] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or elements of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0111] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0112] It should be noted that the above embodiments are illustrative of this application and not restrictive of this application, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims.

Claims

1. An electrode sheet, characterized in that, The electrode includes a current collector and a material layer disposed on at least one side surface of the current collector along a first direction. The material layer includes a first material layer and a second material layer. The first material layer includes a first material, and the second material layer includes a second material. The thermal conductivity of the first material is greater than that of the second material. Along the second direction, at least one end of the electrode is provided with a tab, the first material layer is located in the end region of the current collector near the tab, and along the second direction, the second material layer is located on the side of the first material layer away from the tab, and the first direction and the second direction intersect.

2. The electrode sheet according to claim 1, characterized in that, The electrode sheet has tabs at both ends along the second direction, and the number of the first material layers is at least two. Along the second direction, at least two of the first material layers are located on opposite sides of the second material layer.

3. The electrode sheet according to claim 2, characterized in that, At least two of the first material layers are symmetrically distributed on opposite sides of the second material layer along the second direction.

4. The electrode sheet according to claim 1, characterized in that, The length of the second material layer along the second direction is greater than 0 and less than 2 / 5.

5. The electrode sheet according to claim 1, characterized in that, The thermal conductivity of the first material is 217 W / (m·K)-5300 W / (m·K), and / or the thermal conductivity of the second material is 1 W / (m·K)-217 W / (m·K).

6. The electrode sheet according to claim 1, characterized in that, The first material is graphene, and / or the second material is carbon nanotubes.

7. The electrode sheet according to any one of claims 1-6, characterized in that, The electrode also includes: A dressing layer disposed on the surface of the material layer away from the current collector.

8. A battery cell assembly, characterized in that, The battery cell assembly includes a plurality of positive electrode plates and a plurality of negative electrode plates, wherein at least one of the plurality of positive electrode plates is an electrode plate according to any one of claims 1-6, and / or at least one of the plurality of negative electrode plates is an electrode plate according to any one of claims 1-6, and each of the positive electrode plates and each of the negative electrode plates are alternately stacked along the first direction to form a battery cell assembly.

9. The cell assembly according to claim 8, characterized in that, Along the second direction, each of the positive electrode plates is provided with a positive electrode tab at both ends, and / or each of the negative electrode plates is provided with a negative electrode tab at both ends.

10. The cell assembly according to claim 8, characterized in that, The battery cell assembly also includes multiple separators, each of which is disposed between each pair of adjacent positive and negative electrodes, and all the positive electrodes, all the negative electrodes, and all the separators are alternately stacked along the first direction.

11. The cell assembly according to claim 8, characterized in that, The battery cell assembly has a first side and a second side disposed opposite to each other along a third direction. The battery cell assembly also includes at least one side plate, and at least one side plate is connected to at least one of the first side and the second side. The third direction intersects the first direction and the second direction in pairs.

12. The cell assembly according to claim 11, characterized in that, The side panel away from the battery cell assembly is provided with a side panel adhesive, which is used to bond and fix the side panel to the battery cell assembly.

13. A single-cell battery, characterized in that, It includes a housing and a cell assembly according to any one of claims 8-12, the cell assembly being housed within the housing.

14. The single-cell battery according to claim 13, characterized in that, The battery cell assembly includes multiple positive electrode plates and multiple negative electrode plates. Each positive electrode plate has a positive tab at both ends, and each negative electrode plate has a negative tab at both ends. The housing has a first cover plate and a second cover plate disposed opposite to each other. The first cover plate has a first positive electrode post and a first negative electrode post, and the second cover plate has a second positive electrode post and a second negative electrode post. The first positive electrode post and the second positive electrode post are both electrically connected to the positive tab, and the first negative electrode post and the second negative electrode post are both electrically connected to the negative tab.

15. The single-cell battery according to claim 14, characterized in that, The first cover plate is equipped with an explosion-proof valve, and / or the second cover plate is equipped with a liquid injection hole.

16. The single-cell battery according to claim 13, characterized in that, An insulating film is provided between the housing and the battery cell assembly, and the insulating film covers the circumferential side surface of the battery cell assembly.

17. The single-cell battery according to claim 14, characterized in that, Along the second direction, a first side spacer is provided between the first cover plate and the cell assembly, and / or, a second side spacer is provided between the second cover plate and the cell assembly.

18. A battery device, characterized in that, Includes the single-cell battery according to any one of claims 13-17.

19. An electrical appliance, characterized in that, The electrical device includes the battery device according to claim 18 or the single battery cell according to any one of claims 13-17.

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