Battery device and electric device

Abstract

The embodiment of the utility model provides a battery device and a power utilization device. The battery device comprises a battery monomer group and a plurality of heat insulation pads, the battery monomer group comprises a first sub-group and two second sub-groups, each of the first sub-group and the second sub-groups comprises a plurality of battery monomers arranged along a first direction, and the two second sub-groups are respectively positioned at two ends of the first sub-group along the first direction; the plurality of heat insulation pads are arranged between two adjacent battery monomers; wherein the plurality of heat insulation pads comprise a first heat insulation pad and a second heat insulation pad, the first heat insulation pad is arranged between two adjacent battery cells in the first sub-group, and the second heat insulation pad is arranged between two adjacent battery cells in the second sub-group and between the second sub-group and the first sub-group; the thickness of the frame of the first heat insulation pad is larger than that of the frame of the second heat insulation pad. According to the technical scheme provided by the invention, the safety of the battery device can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery device and a power utilization device. BACKGROUND

[0002] In recent years, new energy vehicles have made a great leap in development. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable important role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also increasing. Among them, the battery device as a core component of new energy vehicles has higher requirements in terms of use stability and use reliability.

[0003] In the battery device, a heat insulation pad is arranged between two adjacent battery monomers to reduce heat transfer between the battery monomers. During use of the battery device, the battery monomers will swell and deform, and the swelling forces received by the battery monomers in different areas of the battery pack have certain differences. The battery device has the risk of damage or life attenuation of the battery monomers due to excessive extrusion, affecting the safety of the battery device. CONTENT OF THE UTILITY MODEL

[0004] The present application provides a battery device and a power utilization device, which can improve the safety of the battery device.

[0005] The present application is realized by the following technical scheme:

[0006] In a first aspect, the present application provides a battery device, which includes a battery monomer group and a plurality of heat insulation pads. The battery monomer group includes a first sub-group and two second sub-groups. The first sub-group and the second sub-groups each include a plurality of battery monomers arranged along a first direction. Along the first direction, the two second sub-groups are respectively located at both ends of the first sub-group. The first direction is perpendicular to the largest outer surface of the battery monomer. The plurality of heat insulation pads are arranged between adjacent battery monomers. The plurality of heat insulation pads include first heat insulation pads and second heat insulation pads. The first heat insulation pads are arranged between adjacent battery monomers in the first sub-group. The second heat insulation pads are arranged between adjacent battery monomers in the second sub-groups and between the second sub-groups and the first sub-group. The thickness of the frame of the first heat insulation pads is greater than the thickness of the frame of the second heat insulation pads.

[0007] In the technical solutions of the embodiments of the present application, the battery monomers in the first sub-group can correspond to the battery monomers in the middle region of the battery monomer group, and the battery monomers in the two second sub-groups correspond to at least part of the battery monomers at the two ends of the first sub-group in the first direction of the battery monomer group. Due to the differences in the expansion force and the required expansion space of the battery monomers in different regions of the battery monomer group, the battery monomers in the middle region of the battery monomer group are subjected to a relatively larger expansion force and require a relatively larger expansion space compared with the battery monomers in the end region or the battery monomers close to the end region of the battery monomer group. Therefore, the first thermal insulation pad is arranged between the adjacent two battery monomers in the first sub-group, the second thermal insulation pad is arranged between the adjacent two battery monomers in the second sub-group and between the second sub-group and the first sub-group, the thickness of the frame of the first thermal insulation pad is greater than the thickness of the frame of the second thermal insulation pad, the first thermal insulation pad has a higher strength than the second thermal insulation pad, and can better meet the requirement of the battery monomers in the middle region of the battery monomer group being subjected to a larger expansion force, while meeting the structural stability of the battery monomer group. The first thermal insulation pad makes the spacing between the adjacent two battery monomers in the first sub-group larger, thereby providing the battery monomers in the middle region of the battery monomer group with a larger expandable space and reducing the risk of the battery monomers in the first sub-group of the battery monomer group being damaged or having a life attenuation due to excessive extrusion caused by an excessively large expansion force. The second thermal insulation pad is arranged between the battery monomers in the end region or the battery monomers close to the end region of the battery monomer group, the thickness of the frame of the second thermal insulation pad is smaller than that of the first thermal insulation pad, can meet the requirement of the battery monomers in the second sub-group being subjected to a relatively small expansion force, and the second thermal insulation pad plays a role in structural stability and thermal insulation for the battery monomers in the second sub-group, prevents the end region of the battery monomer group from loosening, and ensures the structural stability of the battery monomer group.

[0008] That is to say, by differentiating the thermal insulation pads in different regions of the battery monomer group, the first thermal insulation pad with a larger thickness is used between the battery monomers in the first sub-group, and the second thermal insulation pad with a relatively smaller thickness is used between the battery monomers in the second sub-group, which can meet the differentiated requirements of the expansion space in different regions of the battery monomer group while meeting the requirements of the thermal insulation pad in thermal insulation and structural stability, avoid the risk of the battery monomers being damaged or having a life attenuation due to an improper expansion space between the battery monomers of the battery monomer group and excessive extrusion, and improve the safety of the battery device.

[0009] According to some embodiments of the present application, the two second sub-groups include two battery monomers at the two ends in the first direction of the battery monomer group.

[0010] In the above scheme, the two second subgroups include two battery cells at both ends of the battery cell group in the first direction, and the battery cells in the first subgroup and the two second subgroups constitute all battery cells in the battery cell group. The use of two types of heat insulation pads, the first heat insulation pad and the second heat insulation pad, can meet the differentiated expansion force requirement between the battery cells in the battery cell group, and is easy to implement.

[0011] According to some embodiments of the present application, the number of battery cells in the two second subgroups is equal.

[0012] In the above scheme, the number of battery cells in the two second subgroups is equal, so that the first subgroup is completely located in the middle region of the battery cell group along the first direction, and the two second subgroups are respectively located in the end regions at both ends of the middle region of the battery cell group. The expansion force transmitted by the battery cells in the two second subgroups to the battery cells in the first subgroup is symmetrical to each other, and the stress stability of the battery cell group is better.

[0013] According to some embodiments of the present application, the first heat insulation pad comprises a first frame and a first core material, and the first frame surrounds the outer peripheral side of the first core material; the second heat insulation pad comprises a second frame and a second core material, and the second frame surrounds the outer peripheral side of the second core material; the thickness of the first frame is greater than the thickness of the second frame.

[0014] In the above scheme, the first frame serves as the main frame of the first heat insulation pad, and the first frame can provide the first heat insulation pad with mechanical strength, thereby meeting the structural stability of the battery cell group. The first core material is arranged in the first frame, and the first core material can play a role of heat insulation and buffering to provide the battery cells in the first subgroup with a heat insulation and buffering expansion space. The second frame serves as the main frame of the second heat insulation pad, and the second frame can provide the second heat insulation pad with mechanical strength, thereby meeting the structural stability of the battery cell group. The second core material is arranged in the second frame, and the second core material can play a role of heat insulation and buffering to reduce the risk of damage or life attenuation of the battery cells caused by mutual extrusion of the battery cells due to insufficient expansion space.

[0015] According to some embodiments of the present application, the thickness of the first core material is less than the thickness of the first frame, and the thickness of the second core material is less than the thickness of the second frame.

[0016] In the above scheme, the first frame can provide the first heat insulation pad with mechanical strength requirement, and the thickness of the first core material is less than the thickness of the first frame, so that there is a gap between the large surface of the battery cell and the first core material, thereby providing the battery cells in the first subgroup with an expandable deformation space. The thickness of the second core material is less than the thickness of the second frame, so that there is a gap between the large surface of the battery cell and the second core material, thereby providing the battery cells in the second subgroup with an expandable deformation space.

[0017] According to some embodiments of the present application, the thickness of the first core material is less than the thickness of the second core material.

[0018] In the above scheme, the thickness of the first frame is greater than the thickness of the second frame, and the thickness of the first core material is less than the thickness of the second core material, so that the distance between the first core material in the first thermal insulation pad and the corresponding battery monomer in the first sub-group is greater than the distance between the second core material and the corresponding battery monomer in the second sub-group, which can meet the high expansion force characteristics of the battery monomers in the middle region of the battery monomer group, provide more sufficient expandable space for the battery monomers in the middle region of the battery monomer group, reduce the risk of battery monomer damage or service life attenuation caused by mutual extrusion of battery monomers due to insufficient expansion space, and improve the reliability and safety of the battery device.

[0019] According to some embodiments of the present application, the thickness of the first frame is 2.05-2.15mm.

[0020] In the above scheme, the thickness of the first frame is selected to be 2.05-2.15mm, which can not only meet the mechanical strength of the first frame and improve the structural stability of the battery monomer group, but also not occupy too much internal space of the battery monomer group. If the thickness of the first frame is less than 2.05mm, the expansion force of the battery monomers in the middle region of the battery monomer group is larger, and the thickness of the first frame is smaller, which is not easy to meet the strength requirement of the first thermal insulation pad, affecting the structural stability of the battery monomer group. If the thickness of the first frame is greater than 2.15mm, the size of the battery monomer group along the first direction is larger, which is not conducive to the internal space layout of the battery monomer group.

[0021] According to some embodiments of the present application, the thickness of the second frame is 1.85-1.95mm.

[0022] In the above scheme, the thickness of the second frame is selected to be 1.85-1.95mm, which can not only meet the mechanical strength of the second frame and improve the structural stability of the battery monomer group, but also not occupy too much internal space of the battery monomer group. If the thickness of the second frame is less than 1.85mm, the thickness of the second frame is smaller, which is not easy to meet the strength requirement of the second thermal insulation pad, affecting the structural stability of the battery monomer group. If the thickness of the second frame is greater than 1.95mm, the thickness of the second frame is too thick, and the size of the battery monomer group along the first direction is larger, which is not conducive to the internal space layout of the battery monomer group.

[0023] According to some embodiments of the present application, the thickness of the first core material is 0.4-0.6mm, and the thickness of the second core material is 1.6-1.8mm.

[0024] In the above scheme, the thickness of the first core material is limited to 0.4mm-0.6mm, the thickness difference value of the first core material and the first frame is larger, so that the spacing between the battery monomers in the first sub-group and the first core material is larger, which can better meet the expansion space requirement of the battery monomer group with high expansion force, and can also meet the heat insulation performance of the first heat insulation pad. If the thickness of the first core material is less than 0.4mm, the thickness of the first core material is small, which affects the heat insulation performance of the first heat insulation pad, and there is a risk of abnormal heat transfer between the battery monomers. If the thickness of the first core material is greater than 0.6mm, the expansion space of the battery monomers in the first sub-group is not sufficient, and the mutual extrusion between the battery monomers is easy to cause the damage or life attenuation of the battery monomers. The thickness of the second core material is limited to 1.6mm-1.8mm, which can meet the expansion space requirement of the low expansion force of the end region of the battery monomer group, and can also meet the structural stability of the battery monomer group. If the thickness of the second core material is less than 1.6mm, the expansion force of the battery monomers at the end of the battery monomer group is small, so that the gap between the second core material and the battery monomers is large, and the phenomenon of loose battery monomers is easy to appear. If the thickness of the second core material is greater than 1.8mm, the expansion space of the battery monomers in the second sub-group is insufficient, and the mutual extrusion between the battery monomers is easy to cause the damage or life attenuation of the battery monomers.

[0025] According to some embodiments of the present application, the first core material includes aerogel, and the second core material includes aerogel and microcellular polypropylene.

[0026] In the above scheme, the first core material includes aerogel, which can meet the heat insulation performance of the first core material and the compression deformation requirement of the first heat insulation pad, and provide more sufficient expandable space between the battery monomers in the first sub-group. The second core material includes aerogel and microcellular polypropylene, the aerogel has heat insulation performance and compression deformation performance, and the microcellular polypropylene is softer than the aerogel. After the microcellular polypropylene layer and the aerogel are combined, the mechanical strength of the first heat insulation pad can be met, and more sufficient deformable expansion space can be provided for the battery monomers in the second sub-group.

[0027] According to some embodiments of the present application, the first frame includes a first frame body and a first adhesive layer, the first frame body has two first surfaces distributed along the first direction, and the first adhesive layer covers at least part of the first surface. The first frame is bonded to the battery monomer through the first adhesive layer.

[0028] In the above scheme, the first adhesive layer is arranged on the two first surfaces of the first frame body, so that the first heat insulation pad can be bonded to the surface of the corresponding battery monomer through the first adhesive layer. The connection stability of the first heat insulation pad and the battery monomer is good, and the first heat insulation pad is not easy to fall off from the battery monomer, thereby improving the structural stability of the battery device.

[0029] According to some embodiments of the present application, the second frame includes a second frame body and a second adhesive layer, the second frame body has two second surfaces distributed along the first direction, and the second adhesive layer covers at least part of the second surfaces, and the second frame is bonded to the battery cell through the second adhesive layer.

[0030] In the above scheme, the second thermal insulation pad is arranged on the two second surfaces of the second frame body through the second adhesive layer, so that the second thermal insulation pad can be bonded to the surface of the corresponding battery cell through the second adhesive layer, the connection stability of the second thermal insulation pad and the battery cell is good, the second thermal insulation pad is not easy to fall off from the battery cell, and the structural stability of the battery device is improved.

[0031] According to some embodiments of the present application, the number of battery cells in the battery cell group is N, and the number of thermal insulation pads is N-1; the number of first thermal insulation pads is M, which satisfies: (N-1) / 2-1≤M≤(N-1) / 2+3, M is an integer; the number of second thermal insulation pads is Q, which satisfies: Q=N-1-M, and Q is an even number.

[0032] In the above scheme, the number of first thermal insulation pads and second thermal insulation pads is limited, that is, the number of battery cells in the first sub-group in the middle region and the second sub-group in the end region of the battery cell group is divided, so that the number of first thermal insulation pads is M, which satisfies: (N-1) / 2-1≤M≤(N-1) / 2+3, M is an integer, and the number of second thermal insulation pads Q satisfies: 9≤Q≤13, and Q is an even number, so as to adapt to the expansion force and expansion space demand of the battery cells in different regions of the battery cell group under the premise of guaranteeing the mechanical strength and overall performance of the battery module, reduce the phenomenon that the battery cells in the battery cell group are extruded to cause damage or life attenuation of the battery cells, and improve the safety of the battery device.

[0033] In a second aspect, the embodiments of the present application also provide a power utilization device, which includes the battery device of any of the preceding embodiments, and is used for providing electric energy.

[0034] The power utilization device provided by the embodiments of the present application has the same technical effects as the battery device provided by any of the preceding embodiments, and thus repeated description is omitted here.

[0035] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those of ordinary skill in the art, other related drawings can also be obtained from these drawings without creative labor.

[0037] Figure 1 A structural schematic diagram of a vehicle provided for some embodiments of the present application;

[0038] Figure 2 An exploded structural schematic diagram of a battery device provided for some embodiments of the present application;

[0039] Figure 3 An exploded schematic diagram of a battery cell in a battery device provided for some embodiments of the present application;

[0040] Figure 4 A partial exploded schematic diagram of a battery cell group and a heat insulation pad in a battery device provided for some embodiments of the present application;

[0041] Figure 5 A partial exploded schematic diagram of a battery cell group and a heat insulation pad in a battery device provided for some embodiments of the present application;

[0042] Figure 6 A structural schematic diagram of a first heat insulation pad in a battery device provided for some embodiments of the present application;

[0043] Figure 7 A structural schematic diagram of a second heat insulation pad in a battery device provided for some embodiments of the present application;

[0044] Figure 8 A sectional view of a first heat insulation pad in a battery device provided for some embodiments of the present application;

[0045] Figure 9 A sectional view of a second heat insulation pad in a battery device provided for some embodiments of the present application.

[0046] Icon: 1000 - vehicle; 100 - battery device; 200 - controller; 300 - motor; 10 - case; 11 - first sub case; 12 - second sub case; 20 - battery cell; 21 - outer shell; 211 - shell body; 212 - end cover; 213 - first wall; 22 - electrode assembly; 23 - electrode terminal; 24 - battery cell group; 25 - first sub group; 26 - second sub group; 30 - first thermal insulation pad; 31 - first frame; 311 - first frame body; 3111 - first surface; 312 - first adhesive layer; 32 - first core material; 40 - second thermal insulation pad; 41 - second frame; 411 - second frame body; 4111 - second surface; 412 - second adhesive layer; 42 - second core material; X - first direction. DETAILED DESCRIPTION

[0047] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0048] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used in the specification of the present application are only for the purpose of describing the specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion. The terms "first", "second" and the like in the specification and claims of the present application and the above description of drawings are used to distinguish different objects, not to describe a particular order or primary and secondary relationship.

[0049] In the present application, the phrase "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it mutually exclusive or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in the present application can be combined with other embodiments.

[0050] In the description of the present application, it is necessary to point out that, unless otherwise explicitly specified and limited, the terms "mount", "connect", "connection", "attach" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0051] The term "and / or" in the present application is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in the present application generally represents that the front and rear associated objects have an "or" relationship.

[0052] The "multiple" appearing in the present application refers to two or more (including two), and similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces).

[0053] The battery apparatus mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells connected in series, parallel or mixed connection through a busbar component.

[0054] In some embodiments, the battery cell assembly is usually formed by arranging a plurality of battery cells; as an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing a plurality of battery cells into an independent module. As an example, the battery module can be formed by bundling a plurality of battery cells with a cable tie.

[0055] In some embodiments, the battery apparatus can be a battery pack, which includes a box body and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the box body.

[0056] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be accommodated in the box body by fixing the battery module in the box body.

[0057] As an example, the battery cell assembly can also be accommodated in the box body by directly fixing a plurality of battery cells in the box body.

[0058] In some embodiments, the box can be part of a chassis structure of a vehicle. For example, portions of the box can become at least part of a floor of the vehicle, or portions of the box can become at least part of cross members and longitudinal members of the vehicle.

[0059] In some embodiments, the battery device can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0060] In embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0061] The battery cell can be, but is not limited to, a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc.

[0062] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging of the battery cell, active ions (e.g., lithium ions) are inserted and extracted between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode and can prevent the positive and negative electrodes from shorting while allowing the active ions to pass through.

[0063] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0064] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction thereof, and the positive electrode active material is disposed on either one or both of the opposite surfaces of the positive electrode current collector.

[0065] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, stainless steel, stainless steel, copper, aluminum, carbon, nickel, or titanium, etc. with silver plating on the surface can be used. The composite current collector can include a high molecular material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a high molecular material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0066] As an example, the positive electrode active material can include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for battery cells can also be used.

[0067] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0068] As an example, the negative electrode current collector can employ a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver plating surface treatment, stainless steel with a silver plating surface treatment, stainless steel, copper, aluminum, a carbon electrode, carbon, nickel, or titanium, or the like can be employed.

[0069] In some embodiments, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode active material is disposed on either one or both of the two surfaces of the negative electrode current collector.

[0070] As an example, the negative electrode active material can employ a negative electrode active material for a battery cell known in the art. As an example, the negative electrode active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, and lithium titanate, or the like. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative electrode active material for a battery cell can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0071] In some embodiments, the separator is a separation film. The present application does not particularly limit the type of separation film, and any known porous structure separation film having good chemical stability and mechanical stability can be used.

[0072] As an example, the main material of the separation film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separation film can be a single layer film or a multi-layer composite film, and is not particularly limited. When the separation film is a multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separation film can be a separate member located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes.

[0073] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, and functions to transport ions and separate the positive and negative electrodes.

[0074] In some embodiments, the electrode assembly is a roll structure. The positive electrode sheet and the negative electrode sheet are rolled to form the roll structure.

[0075] In some embodiments, the electrode assembly is a stack structure.

[0076] In some embodiments, the battery cell can include a shell. The shell is used to encapsulate components such as the electrode assembly and electrolyte. The shell can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0077] In some embodiments, the shell includes an end cap and a shell body, the shell body is provided with an opening, and the end cap closes the opening to form a sealed space for accommodating the electrode assembly and electrolyte, etc. The shell body can be provided with one or more openings. The end cap can also be provided with one or more openings.

[0078] In some embodiments, at least one electrode terminal is provided on the shell, and the electrode terminal is electrically connected to the tab of the electrode assembly. The electrode terminal can be directly connected to the tab or indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the shell body.

[0079] In some embodiments, an explosion-proof valve is provided on the shell. The explosion-proof valve is used to release the internal pressure of the battery cell.

[0080] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or other shaped battery cells, the prismatic battery cell includes a square battery cell, a blade battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, etc., and the present application is not particularly limited.

[0081] In battery technology, a heat insulation pad is provided between two adjacent battery cells in a battery device to reduce heat transfer between the two battery cells. During use of the battery device, the battery cells will undergo certain swelling deformation. Due to the difference in swelling force and required swelling space of the battery cells in different areas of the battery cell group, especially when the number of battery cells in the battery cell group is large, the difference in swelling force of the battery cells in different positions of the battery device is particularly obvious. The thickness of the heat insulation pad between the two adjacent battery cells is generally designed to be equal, which can easily lead to the risk of damage to the battery cells or life attenuation of the battery cells in some areas of the battery device due to excessive extrusion, affecting the safety of the battery device.

[0082] In view of this, to improve the safety of the battery device, some embodiments of the present application provide a battery device, the battery device comprising a battery cell group and a plurality of thermal insulation pads, the battery cell group comprising a first sub-group and two second sub-groups, the first sub-group and the second sub-groups each comprising a plurality of battery cells arranged along a first direction, along the first direction, the two second sub-groups are respectively located at two ends of the first sub-group, the first direction being perpendicular to the largest outer surface of the battery cell, and the plurality of thermal insulation pads are arranged between adjacent two battery cells; wherein the plurality of thermal insulation pads comprise first thermal insulation pads and second thermal insulation pads, the first thermal insulation pads are arranged between adjacent two battery cells in the first sub-group, and the second thermal insulation pads are arranged between adjacent two battery cells in the second sub-group and between the second sub-group and the first sub-group, and the thickness of the frame of the first thermal insulation pad is greater than the thickness of the frame of the second thermal insulation pad.

[0083] The battery device provided by the embodiments of the present application can meet the differentiated requirements of the expansion space in different regions of the battery cell group by differentiating the design of the thermal insulation pads in different regions of the battery cell group, and can also meet the requirements of the thermal insulation and structural stability of the thermal insulation pads, thereby avoiding the risk of damage or life attenuation of the battery cell caused by excessive extrusion due to improper adaptation of the expansion space between the battery cells of the battery cell group, and improving the safety of the battery device.

[0084] The battery device disclosed by the embodiments of the present application can be used in, but is not limited to, an electric device such as a vehicle, a ship or an aircraft. The power supply system of the electric device can be composed of the battery device disclosed by the present application.

[0085] The technical solutions described in the embodiments of the present application are applicable to various electric devices using battery cells and battery devices, for example, a mobile phone, a portable device, a notebook computer, an electric vehicle, an electric toy, an electric tool, a vehicle, a ship and a spacecraft, for example, the spacecraft includes an airplane, a rocket, a space shuttle and a spaceship.

[0086] The following embodiments are described for convenience of illustration, taking a vehicle as an example of an electric device of an embodiment of the present application.

[0087] Please refer to Figure 1 , Figure 1A structural schematic diagram of a vehicle 1000 is provided for some embodiments of the present application. The vehicle 1000 can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid automobile, or a range extended automobile, etc. The vehicle 1000 is internally provided with a battery device 100, which can be arranged at the bottom, head, or tail of the vehicle 1000. The battery device 100 can be used for power supply of the vehicle 1000, for example, the battery device 100 can be used as an operating power source of the vehicle 1000, for example, for the circuit system of the vehicle 1000, such as for the working power demand of the vehicle 1000 during starting, navigation, and running.

[0088] The vehicle 1000 can further include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the working power demand of the vehicle 1000 during starting, navigation, and running.

[0089] In some embodiments of the present application, the battery device 100 can not only be used as an operating power source of the vehicle 1000, but also be used as a driving power source of the vehicle 1000, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1000.

[0090] Please refer to Figure 2 , Figure 2 A structural exploded schematic diagram of the battery device 100 is provided for some embodiments of the present application. The battery device 100 includes a box body 10 and a battery monomer 20, and the battery monomer 20 is contained in the box body 10. Among them, the box body 10 is used to provide a containing space for the battery monomer 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 can include a first sub-box body 11 and a second sub-box body 12, the first sub-box body 11 and the second sub-box body 12 are mutually covered, and the first sub-box body 11 and the second sub-box body 12 jointly define a containing space for containing the battery monomer 20. The second sub-box body 12 can be a hollow structure with one end open, and the first sub-box body 11 can be a plate structure, which is covered on the open side of the second sub-box body 12, so that the first sub-box body 11 and the second sub-box body 12 jointly define the containing space; the first sub-box body 11 and the second sub-box body 12 can also be hollow structures with one side open, and the open side of the first sub-box body 11 is covered on the open side of the second sub-box body 12.

[0091] In the battery device 100, the battery cells 20 can be multiple, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed manner. The mixed manner means that the multiple battery cells 20 are connected in series and in parallel. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed manner, and the whole of the multiple battery cells 20 is accommodated in the case 10. Of course, the battery device 100 can also be in the form of multiple battery modules, in which the multiple battery cells 20 are connected in series, in parallel, or in a mixed manner, and the multiple battery modules are connected in series, in parallel, or in a mixed manner to form a whole and are accommodated in the case 10.

[0092] The battery device 100 can further include other structures. For example, the battery device 100 can further include a current collector for electrically connecting the multiple battery cells 20.

[0093] Please refer to Figure 3 , Figure 3 An exploded structural schematic view of the battery cell 20 is provided for the embodiments of the present application. The battery cell 20 includes a housing 21, an electrode assembly 22, and an electrode terminal 23. The housing 21 includes a housing body 211 and an end cover 212. The housing body 211 has an opening, and the end cover 212 closes the opening to isolate the internal environment of the battery cell 20 from the external environment.

[0094] The housing body 211 is an assembly for cooperating with the end cover 212 to form the internal environment of the battery cell 20. The formed internal environment can be used to accommodate the electrode assembly 22, electrolyte, and other components. The housing body 211 and the end cover 212 can be independent components. The housing body 211 can be of various shapes and sizes. Specifically, the shape of the housing body 211 can be determined according to the specific shape and size of the electrode assembly 22. The material of the housing body 211 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0095] The end cover 212 refers to a component that covers the opening of the housing body 211 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cover 212 can be adapted to the shape of the housing body 211 to cooperate with the housing body 211. Optionally, the end cover 212 can be made of a material with certain hardness and strength (such as aluminum alloy), so that the end cover 212 is not easy to deform when subjected to extrusion and collision, so that the battery cell 20 can have higher structural strength, and the reliability can also be improved. The end cover 212 can be provided with functional components such as the electrode terminal 23. The end cover 212 includes a first wall 213, and the electrode terminal 23 is arranged on the first wall 213. The electrode terminal 23 can be used to electrically connect with the electrode assembly 22 for outputting or inputting the electrical energy of the battery cell 20. The material of the end cover 212 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not specially limited in the embodiments of the present application.

[0096] The electrode assembly 22 is a component in which an electrochemical reaction occurs in the battery cell 20. One or more electrode assemblies 22 can be contained within the case 211.

[0097] The embodiments of the present application provide a battery device, please refer to Figure 4 and Figure 5 The battery device 100 includes a battery cell group 24 and a plurality of thermal insulation pads, the battery cell group 24 includes a first sub-group 25 and two second sub-groups 26, the first sub-group 25 and the second sub-group 26 each include a plurality of battery cells 20 arranged along a first direction X, along the first direction X, the two second sub-groups 26 are respectively located at two ends of the first sub-group 25, the first direction X is perpendicular to the largest outer surface of the battery cell 20, and the plurality of thermal insulation pads are arranged between adjacent two battery cells 20; wherein the plurality of thermal insulation pads include first thermal insulation pads 30 and second thermal insulation pads 40, the first thermal insulation pads 30 are arranged between adjacent two battery cells 20 in the first sub-group 25, the second thermal insulation pads 40 are arranged between adjacent two battery cells 20 in the second sub-group 26 and between the second sub-group 26 and the first sub-group 25, and the thickness of the frame of the first thermal insulation pad 30 is greater than the thickness of the frame of the second thermal insulation pad 40.

[0098] The first sub-group 25 refers to a plurality of battery cells 20 located in the middle region of the battery cell group 24, that is, the plurality of battery cells 20 in the middle region of the battery cell group 24 constitute the first sub-group 25, and the number of battery cells 20 in the first sub-group 25 can be determined according to actual conditions.

[0099] The second sub-group 26 refers to at least part of the battery cells 20 located in the end region of the battery cell group 24, and the two second sub-groups 26 can include two battery cells 20 at both ends of the battery cell group 24 in the first direction X, or can not include two battery cells 20 at both ends of the battery cell group 24 in the first direction X, which can be determined according to actual conditions. The number of battery cells 20 in the second sub-group 26 can be determined according to actual conditions, and the number of battery cells 20 in the two second sub-groups 26 can be equal or not equal.

[0100] For example, when the two second sub-groups 26 include two battery cells 20 at both ends of the battery cell group 24 in the first direction X, the two battery cells 20 at both ends of the battery cell group 24 in the first direction X belong to the two second sub-groups 26 respectively, and the battery cells 20 in the two second sub-groups 26 and the first sub-group 25 together constitute all the battery cells 20 in the battery cell group 24.

[0101] The number of battery cells 20 in the battery cell group 24 can be various, for example, the number of battery cells 20 in the battery cell group can be 8, 10, 11, 13, 15, 17, 19, 20, 21, 23, or 25, etc. Taking the number of battery cells 20 in the battery cell group 24 as 23 for example, the number of battery cells 20 in the first sub-group 25 can be 11, the first sub-group 25 is located in the middle region of the battery cell group 24, and the number of battery cells 20 at both ends of the first sub-group 25 in the first direction X is 6, that is, the number of battery cells 20 in each second sub-group 26 is 6, and the number of battery cells 20 in the two second sub-groups 26 is 12.

[0102] The thermal insulation pad is arranged between any two adjacent battery cells 20 in the battery cell group 24, that is, between any two adjacent battery cells 20 in the battery cell group 24, one thermal insulation pad is arranged. Specifically, for the square cell 20, the thermal insulation pad is arranged between the large faces of the two adjacent battery cells 20, and the large face is the outer surface with the largest area of the battery cell 20.

[0103] When the battery cell 20 is deformed by swelling, the edge region on the large face of the battery cell 20 has a small swelling amount, and the swelling deformation of the battery cell 20 is mainly concentrated in the middle region of the large face of the battery cell 20, that is, the region where the battery cell 20 contacts the core material in the thermal insulation pad.

[0104] The first thermal insulation pad 30 is arranged between the two adjacent battery cells 20 in the first sub-group 25, that is, the thermal insulation pad arranged between the two adjacent battery cells 20 in the first sub-group 25 is the first thermal insulation pad 30. The second thermal insulation pad 40 is arranged between the two adjacent battery cells 20 in the second sub-group 26 and between the second sub-group 26 and the first sub-group 25, that is, the thermal insulation pad arranged between the two adjacent battery cells 20 in the second sub-group 26 is the second thermal insulation pad 40, and the thermal insulation pad of the two adjacent battery cells 20 between the second sub-group 26 and the first sub-group 25 is also the second thermal insulation pad 40. The second thermal insulation pad 40 is arranged between the second sub-group 26 and the first sub-group 25, which can also be understood as the thermal insulation pad between the battery cell 20 close to the second sub-group 26 in the first sub-group 25 and the battery cell 20 close to the first sub-group 25 in the second sub-group 26 is also the second thermal insulation pad 40.

[0105] The thickness of the frame of the first thermal pad 30 is greater than the thickness of the frame of the second thermal pad 40, which means that the thickness of the first thermal pad 30 along the first direction X is greater than the thickness of the second thermal pad 40 along the first direction X. The thickness of the core material in the first thermal pad 30 and the second thermal pad 40 can be equal or not equal. For example, the thickness of the core material in the first thermal pad 30 can be equal to the thickness of the core material in the second thermal pad 40, or the thickness of the core material in the first thermal pad 30 can be less than the thickness of the core material in the second thermal pad 40.

[0106] During the use of the battery device, the battery cells 20 will swell and deform. The swelling force and the required swelling space of the battery cells 20 in different regions of the battery cell group 24 are different. When the number of battery cells 20 in the battery cell group 24 is large, the swelling forces of the plurality of battery cells 20 are superimposed on each other, and the difference in swelling force is particularly obvious. The battery cells 20 in the first sub-group 25 of the battery cell group 24 are located in the middle region of the battery cell group 24, and the cumulative swelling force of the battery cells 20 in the first sub-group 25 is greater, and the required swelling space is greater. The battery cells 20 in the second sub-group 26 of the battery cell group 24 are located in the end region of the battery cell group 24, and the swelling force of the battery cells 20 in the second sub-group 26 is relatively small, and the required swelling space is small.

[0107] In the technical scheme of the embodiments of the present application, the battery monomers 20 in the first sub-group 25 can correspond to the battery monomers 20 in the middle region of the battery monomer group 24, and the battery monomers 20 in the two second sub-groups 26 correspond to at least part of the battery monomers 20 at the two ends of the first sub-group 25 in the first direction X in the battery monomer group 24 respectively. Because there are differences in the expansion force and the required expansion space of the battery monomers 20 in different regions of the battery monomer group 24, the battery monomers 20 in the middle region of the battery monomer group 24 are subjected to relatively larger expansion force and require relatively larger expansion space compared with the battery monomers 20 in the end region or near the end region of the battery monomer group 24. Therefore, the first heat insulation pad 30 is arranged between the adjacent two battery monomers 20 in the first sub-group 25, the second heat insulation pad 40 is arranged between the adjacent two battery monomers 20 in the second sub-group 26 and between the second sub-group 26 and the first sub-group 25, the thickness of the frame of the first heat insulation pad 30 is greater than the thickness of the frame of the second heat insulation pad 40, the first heat insulation pad 30 has higher strength compared with the second heat insulation pad 40, and can better meet the requirement of the battery monomers 20 in the middle region of the battery monomer group 24 subjected to larger expansion force, while meeting the structural stability of the battery monomer group 24, the first heat insulation pad 30 makes the spacing between the adjacent two battery monomers 20 in the first sub-group 25 larger, thereby providing the battery monomers 20 in the middle region of the battery monomer group 24 with larger expandable space, and reducing the risk of damage or life attenuation of the battery monomers 20 in the first sub-group 25 of the battery monomer group 24 caused by excessive extrusion due to excessive expansion force. The second heat insulation pad 40 is arranged between the battery monomers 20 in the end region or near the end region of the battery monomer group 24, the thickness of the frame of the second heat insulation pad 40 is smaller than that of the first heat insulation pad 30, can adapt to the requirement of the battery monomers 20 in the second sub-group 26 subjected to relatively smaller expansion force, and the second heat insulation pad 40 plays a role in structural stability and heat insulation for the battery monomers 20 in the second sub-group 26, prevents the end region of the battery monomer group 24 from loosening, and guarantees the structural stability of the battery monomer group 24.

[0108] That is to say, the present scheme differentiates the heat insulation pads in different regions of the battery monomer group 24, adopts the first heat insulation pad 30 with larger thickness between the battery monomers in the first sub-group 25, and adopts the second heat insulation pad 40 with relatively smaller thickness between the battery monomers in the second sub-group 26, which can meet the differentiated requirements of the expansion space in different regions of the battery monomer group 24 while taking into account that the heat insulation pad can play a role in heat insulation and structural stability, avoids the risk of damage or life attenuation of the battery monomers 20 caused by excessive extrusion due to improper expansion space between the battery monomers 20 in the battery monomer group 24, and improves the safety of the battery device.

[0109] According to some embodiments of the present application, the two second sub-groups 26 include the two battery monomers 20 at the two ends of the battery monomer group 24 in the first direction X.

[0110] The two second subgroups 26 include two battery cells 20 located at both ends of the first direction X in the battery cell group 24, that is, one of the two second subgroups 26 includes battery cells 20 located at one end of the first direction X in the battery cell group 24, and the other of the two second subgroups 26 includes battery cells 20 located at the other end of the first direction X in the battery cell group 24.

[0111] It can also be understood that the two battery cells 20 located at both ends of the first direction X in the battery cell group 24 are respectively located in the two second subgroups 26, the battery cells 20 in the first subgroup 25 and the two second subgroups 26 constitute all the battery cells 20 in the battery cell group 24, the battery cells 20 in the first subgroup 25 are the battery cells 20 in the middle region of the battery cell group 24, and the battery cells 20 in the second subgroup 26 are the battery cells 20 in the end region of the battery cell group 24.

[0112] The two second subgroups 26 include two battery cells 20 located at both ends of the first direction X in the battery cell group 24, the battery cells 20 in the first subgroup 25 and the two second subgroups 26 constitute all the battery cells 20 in the battery cell group 24, and the use of two types of heat insulation pads, the first heat insulation pad 30 and the second heat insulation pad 40, can meet the differentiated expansion force requirements between the battery cells 20 in the battery cell group 24, and is easy to realize.

[0113] According to some embodiments of the present application, the number of battery cells 20 in the two second subgroups 26 is equal.

[0114] The number of battery cells 20 in the two second subgroups 26 is equal, for example, the number of battery cells 20 in one of the two second subgroups 26 is six, and the number of battery cells 20 in the other of the two second subgroups 26 is also six. If the number of battery cells 20 in one of the two second subgroups 26 is seven, then the number of battery cells 20 in the other of the two second subgroups 26 is also seven.

[0115] The number of battery cells 20 in the two second subgroups 26 is equal, so that the first subgroup 25 is completely located in the middle region of the battery cell group 24 along the first direction X, the two second subgroups 26 are respectively located in the end regions of the middle region of the battery cell group 24, the stress (such as expansion force) transmitted by the battery cells 20 in the two second subgroups 26 to the battery cells 20 in the first subgroup 25 is symmetrical to each other, and the stress stability of the battery cell group 24 is better.

[0116] According to some embodiments of the present application, please refer to Figure 6 and Figure 7The first thermal insulation pad 30 comprises a first edge frame 31 and a first core material 32, and the first edge frame 31 is arranged at the outer circumferential side of the first core material 32. The second thermal insulation pad 40 comprises a second edge frame 41 and a second core material 42, and the second edge frame 41 is arranged at the outer circumferential side of the second core material 42. The thickness of the first edge frame 31 is greater than the thickness of the second edge frame 41.

[0117] The first edge frame 31 is a frame structure, and the first edge frame 31 is arranged at the outer circumferential side of the first core material 32, that is, the outer circumferential side of the first core material 32 is connected with the inner circumferential side of the first edge frame 31. The shape of the first edge frame 31 can be various, for example, the shape of the first edge frame 31 is a rectangular frame, a triangular frame or a circular frame, etc. Taking the rectangular frame as an example, the first core material 32 is a rectangular structure, and the outer circumferential side of the first core material 32 is connected with the second edge frame 41 in a manner of bonding or embedding.

[0118] The second edge frame 41 is a frame structure, and the second edge frame 41 is arranged at the outer circumferential side of the second core material 42, that is, the outer circumferential side of the second core material 42 is connected with the inner circumferential side of the second edge frame 41. The shape of the second edge frame 41 can be various, for example, the shape of the second edge frame 41 is a rectangular frame, a triangular frame or a circular frame, etc. Taking the rectangular frame as an example, the second core material 42 is also a rectangular structure, and the outer circumferential side of the second core material 42 is connected with the second edge frame 41 in a manner of bonding or embedding.

[0119] The material of the first core material 32 is a thermal insulation material, for example, the material of the first core material 32 can be aerogel, and the first core material 32 can play a role of buffering and thermal insulation, and after the first core material 32 is subjected to extrusion force, the first core material 32 can be compressed and deformed by a certain amount. The material of the second core material 42 is also a thermal insulation material, and the second core material 42 can play a role of buffering and thermal insulation, and after the second core material 42 is subjected to extrusion force, the second core material 42 can be compressed and deformed by a certain amount. The material of the second core material 42 can be the same as or different from the material of the first core material 32, which is determined according to actual conditions.

[0120] The first edge frame 31 is the main frame of the first thermal insulation pad 30, and the first edge frame 31 can provide mechanical strength for the first thermal insulation pad 30, so as to meet the structural stability of the battery monomer group 24. The first core material 32 is arranged in the first edge frame 31, and the first core material 32 can play a role of thermal insulation and buffering, and provide a thermal insulation and buffering expansion space for the battery monomer 20 in the first sub-group 25. The second edge frame 41 is the main frame of the second thermal insulation pad 40, and the second edge frame 41 can provide mechanical strength for the second thermal insulation pad 40, so as to meet the structural stability of the battery monomer group 24. The second core material 42 is arranged in the second edge frame 41, and the second core material 42 can play a role of thermal insulation and buffering, and reduce the risk that the battery monomer 20 is damaged or the service life is attenuated due to insufficient expansion space.

[0121] According to some embodiments of the present application, the thickness of the first core material 32 is less than the thickness of the first frame 31, and the thickness of the second core material 42 is less than the thickness of the second frame 41.

[0122] The first frame 31 can provide the mechanical strength requirement for the first thermal insulation pad 30, and the thickness of the first core material 32 is less than the thickness of the first frame 31, so that there is a gap between the large surface of the battery monomer 20 and the first core material 32, providing an expandable deformation space for the battery monomer 20 in the first sub-group 25. The thickness of the second core material 42 is less than the thickness of the second frame 41, so that there is a gap between the large surface of the battery monomer 20 and the second core material 42, providing an expandable deformation space for the battery monomer 20 in the second sub-group 26.

[0123] According to some embodiments of the present application, please refer to Figure 8 and Figure 9 , the thickness of the first core material 32 is less than the thickness of the second core material 42.

[0124] The thickness of the first core material 32 is less than the thickness of the second core material 42 means that the thickness of the first core material 32 is less than the thickness of the second core material 42 along the first direction X when the first core material 32 and the second core material 42 are not extruded and deformed.

[0125] The thickness of the first frame 31 is greater than the thickness of the second frame 41, and the thickness of the first core material 32 is less than the thickness of the second core material 42, so that the distance between the first core material 32 in the first thermal insulation pad 30 and the corresponding battery monomer 20 in the first sub-group 25 is greater than the distance between the second core material 42 and the corresponding battery monomer 20 in the second sub-group 26, which can meet the high expansion force characteristics of the battery monomer 20 in the middle region of the battery monomer group 24, provide more sufficient expandable space for the battery monomer 20 in the middle region of the battery monomer group 24, reduce the risk of damage or life attenuation of the battery monomer 20 due to insufficient expansion space, and improve the reliability and safety of the battery device.

[0126] According to some embodiments of the present application, the thickness of the first frame 31 is 2.05mm-2.15mm.

[0127] The thickness of the first frame 31 is 2.05mm-2.15mm, for example, the thickness of the first frame 31 can be 2.05mm, 2.06mm, 2.08mm, 2.09mm, 2.1mm, 2.12mm, 2.14mm or 2.15mm, etc. The specific thickness of the first frame 31 can be determined according to the actual situation. In this embodiment, the thickness of the first frame 31 is 2.1mm.

[0128] The thickness of the first frame 31 is selected to be 2.05mm-2.15mm, which can meet the mechanical strength of the first frame 31, improve the structural stability of the battery monomer group 24, and not excessively occupy the internal space of the battery monomer group 24. If the thickness of the first frame 31 is less than 2.05mm, the battery monomer 20 in the middle region of the battery monomer group 24 is subjected to a larger expansion force, and the thickness of the first frame 31 is smaller, which is not easy to meet the strength requirement of the first heat insulation pad 30, and affects the structural stability of the battery monomer group 24. If the thickness of the first frame 31 is greater than 2.15mm, the size of the battery monomer group 24 along the first direction X is larger, which is not conducive to the internal space layout of the battery monomer group 24.

[0129] According to some embodiments of the present application, the thickness of the second frame 41 is 1.85mm-1.95mm.

[0130] The thickness of the second frame 41 is 1.85mm-1.95mm, for example, the thickness of the second frame 41 can be 1.85mm, 1.87mm, 1.89mm, 1.9mm, 1.91mm, 1.93mm or 1.95mm, etc., and the specific thickness of the second frame 41 can be determined according to the actual situation.

[0131] The thickness of the second frame 41 is selected to be 1.85mm-1.95mm, which can meet the mechanical strength of the second frame 41, improve the structural stability of the battery monomer group 24, and not excessively occupy the internal space of the battery monomer group 24. If the thickness of the second frame 41 is less than 1.85mm, the thickness of the second frame 41 is smaller, which is not easy to meet the strength requirement of the second heat insulation pad 40, and affects the structural stability of the battery monomer group 24. If the thickness of the second frame 41 is greater than 1.95mm, the thickness of the second frame 41 is too thick, which occupies a larger size of the battery monomer group 24 along the first direction X, which is not conducive to the internal space layout of the battery monomer group 24.

[0132] According to some embodiments of the present application, the thickness of the first core material 32 is 0.4mm-0.6mm, and the thickness of the second core material 42 is 1.6mm-1.8mm.

[0133] The thickness of the first core material 32 is 0.4mm-0.6mm, for example, the thickness of the first core material 32 can be 0.4mm, 0.45mm, 0.5mm, 0.55mm or 0.6mm, etc., and the specific thickness of the first core material 32 can be determined according to the actual situation.

[0134] The thickness of the second core material 42 is 1.6 mm-1.8 mm, for example, the thickness of the second core material 42 can be 1.6 mm, 1.65 mm, 1.7 mm, 1.75 mm or 1.8 mm, etc., and the specific thickness of the second core material 42 can be determined according to the actual situation. For example, the thickness of the first core material 32 is 0.5 mm, and the thickness of the second core material 42 is 1.8 mm.

[0135] The thickness of the first core material 32 is limited to 0.4 mm-0.6 mm, and the thickness difference between the first core material 32 and the first frame 31 is large, so that the spacing between the battery monomers 20 in the first sub-group 25 and the first core material 32 is larger, which can better meet the expansion space requirement of the battery monomer group 24 with high expansion force, and also meet the heat insulation performance of the first heat insulation pad 30. If the thickness of the first core material 32 is less than 0.4 mm, the thickness of the first core material 32 is small, which affects the heat insulation performance of the first heat insulation pad 30, and there is a risk of abnormal heat transfer between the battery monomers 20. If the thickness of the first core material 32 is greater than 0.6 mm, the expansion space of the battery monomers 20 in the first sub-group 25 is not sufficient, and the mutual extrusion between the battery monomers 20 easily leads to damage or life attenuation of the battery monomers 20.

[0136] The thickness of the second core material 42 is limited to 1.6 mm-1.8 mm, which can meet the expansion space requirement of the low expansion force of the end region of the battery monomer group 24, and also meet the structural stability of the battery monomer group 24. If the thickness of the second core material 42 is less than 1.6 mm, the expansion force of the battery monomers 20 at the end of the battery monomer group 24 is small, so that the gap between the second core material 42 and the battery monomers 20 is large, and the phenomenon of loose battery monomers 20 is easily appeared. If the thickness of the second core material 42 is greater than 1.8 mm, the expansion space of the battery monomers 20 in the second sub-group 26 is insufficient, and the mutual extrusion between the battery monomers 20 easily leads to damage or life attenuation of the battery monomers 20.

[0137] According to some embodiments of the present application, the first core material 32 comprises aerogel, and the second core material 42 comprises aerogel and microcellular polypropylene foam.

[0138] Aerogel refers to a kind of nanometer porous solid material formed by replacing liquid phase in gel with gas through sol-gel method and a certain drying method. Microcellular polypropylene foam (MPP) is a kind of porous foam material.

[0139] The material of microcellular polypropylene foam is softer than aerogel, and the compressible deformation ability of the second core material 42 is stronger when the thickness of the second core material 42 is thicker.

[0140] The first core material 32 includes aerogel, and when the thickness of the first core material 32 is 0.5 mm, the thickness of the aerogel is 0.5 mm.

[0141] The second core material 42 includes aerogel and microcellular polypropylene, and when the thickness of the second core material 42 is 1.8 mm, the thickness of the aerogel can be 0.5 mm, and the thickness of the microcellular polypropylene can be 1.3 mm.

[0142] The first core material 32 includes aerogel, which can meet the heat insulation performance of the first core material 32 and the compression deformation requirement of the first heat insulation pad 30, and provide more sufficient expandable space for the battery monomer 20 in the first sub-group 25. The second core material 42 includes aerogel and microcellular polypropylene, the aerogel has heat insulation performance and compression deformation performance, and the microcellular polypropylene is softer than the aerogel. After the microcellular polypropylene layer and the aerogel are combined, the second core material 42 can meet the mechanical strength of the first heat insulation pad 30 and provide more sufficient deformable expansion space for the battery monomer 20 in the second sub-group 26.

[0143] According to some embodiments of the present application, please refer to Figure 8 The first frame 31 includes a first frame body 311 and a first adhesive layer 312. The first frame body 311 has two first surfaces 3111 distributed along the first direction X. The first adhesive layer 312 covers at least part of the first surface 3111. The first frame 31 is bonded to the battery monomer 20 through the first adhesive layer 312.

[0144] The first surface 3111 refers to the surface of the first frame 31 facing the battery monomer 20. The number of the first adhesive layer 312 corresponds to two, and the two first adhesive layers 312 are respectively arranged on the two first surfaces 3111.

[0145] The first adhesive layer 312 can be double-sided adhesive paper. The first adhesive layer 312 is pasted on the first frame body 311. The side of the first adhesive layer 312 away from the first frame body 311 is used to bond to the large surface of the battery monomer 20.

[0146] The first adhesive layer 312 is arranged on the two first surfaces 3111 of the first frame body 311. In this way, the first heat insulation pad 30 can be bonded to the surface of the corresponding battery monomer 20 through the first adhesive layer 312. The connection stability of the first heat insulation pad 30 and the battery monomer 20 is good. The first heat insulation pad 30 is not easy to fall off from the battery monomer 20, and the structural stability of the battery device is improved.

[0147] According to some embodiments of the present application, please refer to Figure 9The second frame 41 includes a second frame body 411 and a second adhesive layer 412. The second frame body 411 has two second surfaces 4111 distributed along the first direction X. The second adhesive layer 412 covers at least a portion of the second surfaces 4111. The second frame 41 is bonded to the battery cell 20 through the second adhesive layer 412.

[0148] The second surface 4111 refers to the surface of the second frame 41 facing the battery cell 20. There are two second adhesive layers 412, which are respectively disposed on the two second surfaces 4111.

[0149] The second adhesive layer 412 can be double-sided adhesive paper. The second adhesive layer 412 is pasted on the second frame 411. The side of the second adhesive layer 412 facing away from the second frame 411 is used to bond with the large surface of the battery cell 20.

[0150] By setting the second adhesive layer 412 on the two second surfaces 4111 of the second frame 411, the second heat insulation pad 40 can be bonded to the surface of the corresponding battery cell 20 through the second adhesive layer 412. The connection stability between the second heat insulation pad 40 and the battery cell 20 is good, and the second heat insulation pad 40 is not easy to fall off from the battery cell 20, thereby improving the structural stability of the battery device.

[0151] According to some embodiments of this application, the number of battery cells 20 in the battery cell group 24 is N, and the number of heat insulation pads is N-1; the number of first heat insulation pads 30 is M, satisfying: (N-1) / 2-1≤M≤(N-1) / 2+3, where M is an integer; the number of second heat insulation pads 40 is Q, satisfying: Q=N-1-M, where Q is an even number.

[0152] For example, please refer to Figure 4 If the number of battery cells 20 in the battery cell group 24 is N=23, then the number of heat insulation pads is 22. Therefore, the number M of the first heat insulation pads 30 satisfies: 10≤M≤14. The number Q of the second heat insulation pads 40 satisfies: 8≤Q≤12, and Q is an even value, meaning Q can be 8, 10, or 12. Therefore, the number M of the first heat insulation pads 30 can be 10, 12, or 14. In this embodiment, the number M of the first heat insulation pads 30 is 10, the number Q of the second heat insulation pads 40 is 12, and the number of second heat insulation pads 40 on both sides of the first direction X in the first subgroup 25 is 6 each.

[0153] With the number of battery cells 20 in the battery cell group 24 N = 24, the number of thermal insulation pads is 23, then the number of the first thermal insulation pads 30 M satisfies: 10.5 ≤ M ≤ 14.5, and the number of the second thermal insulation pads 40 Q satisfies: 8.5 ≤ Q ≤ 12.5, and Q is an even value, that is, Q can be 10 or 12. Then the value of M can be 13 or 11.

[0154] With the number of battery cells 20 in the battery cell group 24 N = 25, the number of thermal insulation pads is 24, then the number of the first thermal insulation pads 30 M satisfies: 11 ≤ M ≤ 15, and the number of the second thermal insulation pads 40 Q satisfies: 9 ≤ Q ≤ 13, and Q is an even value, that is, Q can be 10 or 12. Then the value of M can be 14 or 12.

[0155] The number of the first thermal insulation pads 30 and the second thermal insulation pads 40 is limited, that is, the number of battery cells 20 in the first sub-group 25 in the middle region and the second sub-group 26 in the end region of the battery cell group 24 is divided, so that the number of the first thermal insulation pads 30 M satisfies: (N-1) / 2-1 ≤ M ≤ (N-1) / 2+3, M is an integer, and the number of the second thermal insulation pads 40 Q satisfies: 9 ≤ Q ≤ 13, and Q is an even value, so as to adapt to the expansion force and expansion space demand of the battery cells 20 in different regions of the battery cell group 24 under the premise of guaranteeing the mechanical strength and overall performance of the battery cell group, reduce the phenomenon that the battery cells 20 in the battery cell group 24 are pressed to cause damage or life attenuation of the battery cells 20, and improve the safety of the battery device.

[0156] In some embodiments, please refer to Figures 4 to 9The battery device 100 comprises a battery cell group 24 and a plurality of thermal insulation pads, the battery cell group 24 comprises a first sub-group 25 and two second sub-groups 26, the first sub-group 25 and the second sub-group 26 each comprise a plurality of battery cells 20 arranged along a first direction X, along the first direction X, the two second sub-groups 26 are respectively located at two ends of the first sub-group 25, and the two second sub-groups 26 comprise two battery cells 20 located at two ends of the battery cell group 24 along the first direction X, the first direction X is perpendicular to the largest outer surface of the battery cell 20, and the plurality of thermal insulation pads are arranged between adjacent two battery cells 20; wherein the plurality of thermal insulation pads comprise first thermal insulation pads 30 and second thermal insulation pads 40, the first thermal insulation pads 30 are arranged between adjacent two battery cells 20 in the first sub-group 25, the second thermal insulation pads 40 are arranged between adjacent two battery cells 20 in the second sub-group 26 and between the second sub-group 26 and the first sub-group 25, and the thickness of the frame of the first thermal insulation pad 30 is greater than the thickness of the frame of the second thermal insulation pad 40. The first thermal insulation pad 30 comprises a first frame 31 and a first core material 32, and the first frame 31 is arranged on the outer circumferential side of the first core material 32; the second thermal insulation pad 40 comprises a second frame 41 and a second core material 42, and the second frame 41 is arranged on the outer circumferential side of the second core material 42; the thickness of the first frame 31 is greater than the thickness of the second frame 41, the thickness of the first core material 32 is less than the thickness of the first frame 31, the thickness of the second core material 42 is less than the thickness of the second frame 41, and the thickness of the first core material 32 is less than the thickness of the second core material 42.

[0157] By differentiating the thermal insulation pads in different regions of the battery cell group 24, the thermal insulation pads in the middle region of the battery cell group 24 are designed to have a larger thickness, and the thermal insulation pads in the end region of the battery cell group 24 are designed to have a relatively smaller thickness, which can meet the differentiated expansion space requirements of different regions of the battery cell group 24 while ensuring that the thermal insulation pads can play a role in heat insulation and structural stability, thereby avoiding the risk of damage or life attenuation of the battery cells 20 due to excessive extrusion caused by improper expansion space adaptation between the battery cells 20 in the battery cell group 24, and improving the safety of the battery device. The thickness of the first frame 31 is greater than the thickness of the second frame 41, and the thickness of the first core material 32 is less than the thickness of the second core material 42, so that the distance between the first core material 32 in the first thermal insulation pad 30 and the corresponding battery cell 20 in the first sub-group 25 is greater than the distance between the second core material 42 and the corresponding battery cell 20 in the second sub-group 26, which can meet the high expansion force characteristics of the battery cells 20 in the middle region of the battery cell group 24, provide more sufficient expandable space for the battery cells 20 in the middle region of the battery cell group 24, reduce the risk of damage or life attenuation of the battery cells 20 caused by mutual extrusion due to insufficient expansion space, and improve the reliability and safety of the battery device.

[0158] In some embodiments, the first core material 32 comprises aerogel, and the second core material 42 comprises aerogel and microcellular polypropylene. The first frame 31 comprises a first frame body 311 and a first adhesive layer 312, the first frame body 311 has two first surfaces 3111 distributed along the first direction X, and the first adhesive layer 312 covers at least part of the first surfaces 3111, and the first frame 31 is bonded to the battery monomer 20 through the first adhesive layer 312. The second frame 41 comprises a second frame body 411 and a second adhesive layer 412, the second frame body 411 has two second surfaces 4111 distributed along the first direction X, and the second adhesive layer 412 covers at least part of the second surfaces 4111, and the second frame 41 is bonded to the battery monomer 20 through the second adhesive layer 412.

[0159] The first core material 32 comprises aerogel, which can meet the heat insulation performance of the first core material 32 and the compression deformation requirement of the first heat insulation pad 30, and provide more sufficient expandable space for the battery monomers 20 in the first sub-group 25. The second core material 42 comprises aerogel and microcellular polypropylene, the aerogel has heat insulation performance and compression deformation performance, and the microcellular polypropylene is softer than the aerogel. After the microcellular polypropylene layer and the aerogel are combined, the second core material 42 can provide more sufficient deformable expansion space for the battery monomers 20 in the second sub-group 26 under the condition that the mechanical strength of the first heat insulation pad 30 is met. The first heat insulation pad 30 can be bonded to the surface of the corresponding battery monomer 20 through the first adhesive layer 312, the connection stability of the first heat insulation pad 30 and the battery monomer 20 is good, and the first heat insulation pad 30 is not easy to fall off from the battery monomer 20, thereby improving the structural stability of the battery device. The second heat insulation pad 40 can be bonded to the surface of the corresponding battery monomer 20 through the second adhesive layer 412, the connection stability of the second heat insulation pad 40 and the battery monomer 20 is good, and the second heat insulation pad 40 is not easy to fall off from the battery monomer 20, thereby improving the structural stability of the battery device 100.

[0160] Although the present application has been described with reference to the preferred embodiments, various modifications can be made to it without departing from the scope of the application, and equivalent components can be substituted therefor. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery device, characterized in that, include: A battery cell group includes a first subgroup and two second subgroups. Both the first subgroup and the second subgroup include multiple battery cells arranged along a first direction. Along the first direction, the two second subgroups are located at the two ends of the first subgroup. The first direction is perpendicular to the outer surface of the battery cell with the largest area. Multiple heat insulation pads are disposed between two adjacent battery cells; The plurality of heat insulation pads include a first heat insulation pad and a second heat insulation pad. The first heat insulation pad is disposed between two adjacent battery cells in the first subgroup, and the second heat insulation pad is disposed between two adjacent battery cells in the second subgroup and between the second subgroup and the first subgroup. Along the first direction, the thickness of the edge of the first heat insulation pad is greater than the thickness of the edge of the second heat insulation pad.

2. The battery device according to claim 1, characterized in that, The two second subgroups include two battery cells located at both ends of the battery cell group in the first direction.

3. The battery device according to claim 1 or 2, characterized in that, The number of battery cells in the two second subgroups is equal.

4. The battery device according to claim 1, characterized in that, The first heat insulation pad includes a first frame and a first core material, wherein the first frame surrounds the outer periphery of the first core material; The second heat insulation pad includes a second frame and a second core material, wherein the second frame surrounds the outer periphery of the second core material; the thickness of the first frame is greater than the thickness of the second frame.

5. The battery device according to claim 4, characterized in that, The thickness of the first core material is less than the thickness of the first frame, and the thickness of the second core material is less than the thickness of the second frame.

6. The battery device according to claim 4, characterized in that, The thickness of the first core material is less than the thickness of the second core material.

7. The battery device according to claim 4, characterized in that, The thickness of the first frame is 2.05mm-2.15mm.

8. The battery device according to claim 4, characterized in that, The thickness of the second frame is 1.85mm-1.95mm.

9. The battery device according to claim 4, characterized in that, The thickness of the first core material is 0.4mm-0.6mm, and the thickness of the second core material is 1.6mm-1.8mm.

10. The battery device according to claim 9, characterized in that, The first core material includes aerogel, and the second core material includes aerogel and microporous foamed polypropylene.

11. The battery device according to claim 4, characterized in that, The first frame includes a first frame body and a first adhesive layer. The first frame body has two first surfaces distributed along the first direction. The first adhesive layer covers at least a portion of the first surfaces. The first frame is bonded to the battery cell through the first adhesive layer.

12. The battery device according to claim 4, characterized in that, The second frame includes a second frame body and a second adhesive layer. The second frame body has two second surfaces distributed along the first direction. The second adhesive layer covers at least a portion of the second surfaces. The second frame is bonded to the battery cell through the second adhesive layer.

13. The battery device according to claim 1, characterized in that, The number of battery cells in the battery cell group is N, and the number of heat insulation pads is N-1; The number of the first heat insulation pads is M, which satisfies: (N-1) / 2-1≤M≤(N-1) / 2+3, where M is an integer; The number of the second heat insulation pads is Q, which satisfies: Q = N-1-M, where Q is an even number.

14. An electrical appliance, characterized in that, The device includes a battery device according to any one of claims 1-13, wherein the power supply device is used to provide electrical energy.

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