Battery cell, battery device, energy storage device, energy storage system and charging network

Abstract

The embodiment of the utility model provides a battery monomer, a battery device, an energy storage device, an energy storage system and a charging network. The battery monomer comprises a shell, an electrode assembly, a first insulating part and a second insulating part, the shell comprises a shell and an end cover assembly, the electrode assembly comprises a main body part and a first tab, the end cover assembly is positioned on one side of the main body part along a first direction, the main body part is provided with a first end surface facing the end cover assembly, and the first tab extends out from the first end surface; the first insulating part covers the outer peripheral surface of the main body part, and the first insulating part is provided with a first part corresponding to the outer surface with the largest area of the main body part; one end of the second insulating part is connected with the end cover assembly, and the other end of the second insulating part is connected with the first part; and in the second direction, the second insulating part is located between the first tab and the shell, and on the same projection plane perpendicular to the second direction, the orthographic projection of the second insulating part covers the orthographic projection of the first tab. According to the technical scheme provided by the invention, the safety of the battery monomer can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery monomer, a battery device, an energy storage device, an energy storage system and a charging network. BACKGROUND

[0002] In recent years, new energy vehicles have developed by leaps and bounds. 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] With the popularity of electric vehicles and the improvement of energy density, electric vehicle fire accidents occur from time to time, and most of the electric vehicle fire accidents are caused by thermal runaway of the battery. Therefore, how to improve the safety of the battery is a technical problem that needs to be solved in the battery technology. CONTENT OF THE INVENTION

[0004] The present application provides a battery monomer, a battery device, an energy storage device, an energy storage system and a charging network, which can improve the safety of the battery monomer.

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

[0006] In a first aspect, the present application provides a battery monomer, which comprises a shell, an electrode assembly, a first insulating member and a second insulating member. The shell comprises a shell body and an end cover assembly. The shell body has a first opening, and the end cover assembly closes the first opening. The electrode assembly is arranged in the shell body. The electrode assembly comprises a main body and a first tab. The end cover assembly is located on one side of the main body along a first direction. The main body has a first end face facing the end cover assembly, and the first tab extends from the first end face. The first insulating member covers the outer circumferential surface of the main body. The first insulating member has a first part corresponding to the largest outer surface of the main body. Along the first direction, one end of the second insulating member is connected with the end cover assembly, and the other end of the second insulating member is connected with the first part. Along a second direction, the second insulating member is located between the first tab and the shell body. On the same projection plane perpendicular to the second direction, the orthogonal projection of the second insulating member covers the orthogonal projection of the first tab. On the same projection plane perpendicular to a third direction, the orthogonal projection of the second insulating member does not block the orthogonal projection of the main body. The third direction, the second direction and the first direction are perpendicular to each other, and the second direction is parallel to the thickness direction of the electrode assembly.

[0007] In the technical scheme of the embodiment of the present application, the first insulating member is wrapped around the outer circumferential surface of the main body part, and can play an insulating role between the outer circumferential surface of the electrode assembly and the inner wall of the shell. In the second direction, the second insulating member is located between the first tab and the shell, and in the same projection plane perpendicular to the second direction, the orthogonal projection of the second insulating member covers the orthogonal projection of the first tab. The second insulating member can separate the first tab and the inner wall of the shell, reduce the risk of short circuit of the first tab in the second direction due to the overlap of the first tab and the shell, and play an insulating protection role on the first tab.

[0008] In addition, the first insulating member wraps the outer circumferential surface of the electrode assembly and can not wrap the bottom surface side of the electrode assembly, and the orthogonal projection of the second insulating member does not block the orthogonal projection of the main body part in the third direction. The second insulating member does not wrap the side surface area of the main body part except the large surface, so that the bottom surface of the electrode assembly and the shell, and the part of the side surface of the electrode assembly close to the second insulating member and the second insulating member form an exhaust gap. When the battery monomer is in thermal runaway, the exhaust gap can provide an exhaust passage for the gas flow in the shell, which is more conducive to the smooth exhaust of the gas, increases the exhaust path, and improves the safety of the battery monomer.

[0009] According to some embodiments of the present application, in the same projection plane perpendicular to the first direction, the orthogonal projection of the first insulating member surrounds the orthogonal projection of the main body part.

[0010] In the above scheme, the orthogonal projection of the first insulating member surrounds the orthogonal projection of the main body part, the first insulating member wraps the outer circumferential surface of the main body part and does not wrap the bottom surface side of the main body part, so that an exhaust gap can be formed between the bottom surface of the electrode assembly and the shell. When the battery monomer is in thermal runaway, it is conducive to the smooth exhaust of the gas.

[0011] According to some embodiments of the present application, the second insulating member includes a body and two bending parts connected to each other. The body is arranged between the end cover assembly and the main body part and connected to the end cover assembly. In the first direction, the body at least partially overlaps the first end surface. The body has a first through hole for avoiding the first tab. The two bending parts are arranged in the second direction and spaced apart. The body is located between the two bending parts. In the second direction, the bending part is located between the body and the shell. The first insulating member has two first parts arranged in the second direction and spaced apart. The two bending parts are respectively arranged corresponding to the two first parts. The end of the bending part away from the body in the first direction is connected to the corresponding first part. In the same projection plane perpendicular to the second direction, the orthogonal projection of the bending part covers the orthogonal projection of the first tab.

[0012] In the above scheme, the second insulating piece is used as the body and the two bending parts, the body is arranged between the end cover assembly and the main body part and connected with the end cover assembly, along the second direction, the bending parts are located between the body and the shell, the two bending parts correspond to the two first parts of the electrode assembly respectively, on the same projection plane perpendicular to the second direction, the normal projection of the bending part covers the normal projection of the first tab, the second insulating piece realizes the insulation between the two sides of the first tab in the second direction and the shell through the two bending parts, reduces the risk of short circuit of the first tab in the second direction and the shell, and improves the safety of the battery monomer.

[0013] According to some embodiments of the present application, the second insulating piece and the electrode assembly form an accommodation space, and two ends of the accommodation space in the third direction form second openings.

[0014] In the above scheme, through the arrangement of the second opening in the accommodation space formed by the second insulating piece and the electrode assembly, when the battery monomer is in thermal runaway, the gas can enter from the second opening and finally be discharged from the pressure relief mechanism of the end cover assembly, thereby increasing the exhaust gap for gas discharge.

[0015] According to some embodiments of the present application, the bending part has a first end and a second end along the third direction, the main body part has a third end and a fourth end along the third direction, the first end is arranged correspondingly with the third end, and the second end is arranged correspondingly with the fourth end, the first end and the third end have a first gap therebetween, and the second end and the fourth end have a second gap therebetween.

[0016] In the above scheme, the first end and the third end of the bending part have a first gap therebetween along the third direction, and the second end and the fourth end have a second gap therebetween, under the premise that the second insulating piece can insulate and protect the first tab, the bending part of the second insulating piece does not need to completely cover the main body part in the third direction, thereby reducing the length of the bending part of the second insulating piece in the third direction and saving materials. Moreover, the first gap and the second gap between the bending part and the main body part can form an exhaust gap, when the battery monomer is in thermal runaway, the exhaust gap and the exhaust path for gas circulation are increased, so that the gas can be discharged more smoothly, and the safety of the battery monomer is improved.

[0017] According to some embodiments of the present application, the bending part is provided with a positioning hole, on the same projection plane perpendicular to the second direction, the normal projection of the positioning hole does not overlap with the normal projection of the first tab, and the normal projection of the positioning hole does not overlap with the normal projection of the main body part.

[0018] In the above scheme, by arranging the positioning hole on the bending part, on the one hand, the positioning hole is convenient for positioning with the tooling fixture during assembly of the second insulating piece, facilitating assembly and positioning of the battery monomer. On the other hand, by arranging the positioning hole so that the orthographic projection of the positioning hole does not overlap the orthographic projection of the first tab and the orthographic projection of the main body part, the positioning hole on the bending part can avoid the position of the main body part of the electrode assembly and the first tab. When the battery monomer is in thermal runaway, the positioning hole increases the exhaust passage of the gas in the battery monomer, and the positioning hole is staggered with the position of the first tab. When the gas in the battery monomer passes through the positioning hole and is discharged, it will not impact the tab, improving the safety of the battery monomer.

[0019] According to some embodiments of the present application, the number of positioning holes is multiple, and the multiple positioning holes are arranged at intervals along the third direction.

[0020] In the above scheme, the number of positioning holes is multiple, and the multiple positioning holes are arranged at intervals. When the second insulating piece is assembled and positioned, the corresponding positioning hole is selected to assemble and position with the tooling fixture, improving the positioning accuracy. And the multiple positioning holes also increase the number of exhaust passages. When the battery monomer is in thermal runaway, the exhaust is more smooth, and the safety of the battery monomer is higher.

[0021] According to some embodiments of the present application, the bending part and the body are connected through a transition part, and the transition part is provided with multiple second through holes at intervals along the third direction.

[0022] In the above scheme, multiple second through holes are arranged on the transition part along the third direction. The arrangement of multiple second through holes can reduce the bending strength of the transition part. After the bending part is subjected to external force, it can be easily bent and deformed relative to the body. It can be convenient to bend the bending part relative to the body, so that the bending part abuts and connects with the first part of the first insulating piece.

[0023] According to some embodiments of the present application, along the third direction, the length of the second through hole is L1, satisfying 0.8mm≤L1≤1.2mm; and / or, along the third direction, the distance between the adjacent two second through holes is L2, satisfying 0.8mm≤L2≤1.2mm.

[0024] In the above scheme, the length of the second through hole is limited to 0.8mm-1.2mm, which can not only ensure the strength of the transition part, but also facilitate the folding of the bending part relative to the body. If the length of the second through hole is less than 0.8mm, the bending strength of the transition part is relatively large, which is not conducive to the folding of the bending part. If the length of the second through hole is greater than 1.2mm, the size of the second through hole is too large, which affects the strength of the transition part, thereby affecting the structural strength of the bending part of the second insulating piece. Similarly, the spacing between the two adjacent second through holes is limited to 0.8mm-1.2mm, which can not only ensure the strength of the transition part, but also facilitate the folding of the bending part. If the spacing between the two adjacent second through holes is less than 0.8mm, the multiple second through holes on the transition part are distributed more densely, which affects the strength of the transition part, thereby affecting the structural strength of the bending part of the second insulating piece. If the spacing between the two adjacent second through holes is greater than 1.2mm, the multiple second through holes are distributed more dispersedly, and the bending strength of the transition part is relatively large, which is not conducive to the folding of the bending part.

[0025] According to some embodiments of the present application, the thickness of the second insulating piece is 0.03mm-0.2mm.

[0026] In the above scheme, the thickness of the second insulating piece is limited to 0.03mm-0.2mm, which can not only ensure the structural strength of the second insulating piece, facilitate the forming quality of the second insulating piece, but also reduce the space occupied in the thickness direction of the second insulating piece. If the thickness of the second insulating piece is less than 0.03mm, the thickness of the second insulating piece is small, and the strength of the second insulating piece is relatively small, which affects the connection strength of the second insulating piece. If the thickness of the second insulating piece is greater than 0.2mm, the strength of the second insulating piece is relatively large, and the space occupied by the second insulating piece is larger, which is not conducive to the space layout of the electrode assembly and the end cover assembly inside the shell.

[0027] According to some embodiments of the present application, the end cover assembly comprises a first wall, a third insulating piece and a first electrode terminal, the first electrode terminal is arranged on the first wall, the third insulating piece is connected with the first wall, and the third insulating piece is located between the first wall and the body, and the body is connected with the third insulating piece.

[0028] In the above scheme, the third insulating piece is arranged between the second insulating piece and the first wall. The third insulating piece plays an insulating role in the end cover assembly, reduces the risk of short circuit caused by the lap joint of the first tab and the first wall, and is connected with the body to fix the second insulating piece, thereby improving the installation stability of the second insulating piece.

[0029] According to some embodiments of the present application, the battery monomer further comprises a first adapter, the first tab is connected with the first electrode terminal through the first adapter; along the first direction, part of the second insulating piece is arranged between the third insulating piece and the first adapter.

[0030] In the above scheme, the first adapter is arranged to facilitate the first lug to be connected with the first electrode terminal through the first adapter. In the first direction, the first adapter and the third insulating piece are respectively located on the two sides of the second insulating piece, and the first adapter can clamp and position the second insulating piece relative to the third insulating piece of the end cover assembly, so that the installation stability of the second insulating piece is higher.

[0031] According to some embodiments of the present application, the end cover assembly further comprises a pressure relief mechanism, and the second insulating piece has a third through hole for avoiding the pressure relief mechanism.

[0032] In the above scheme, by arranging the third through hole on the second insulating piece, the third through hole can avoid the pressure relief mechanism on the end cover assembly, reduce the phenomenon of assembly interference, and will not affect the normal work of the pressure relief mechanism.

[0033] In a second aspect, the embodiments of the present application further provide a battery device, which comprises the battery monomer of any of the foregoing embodiments.

[0034] In a third aspect, the embodiments of the present application further provide an energy storage device, which comprises the battery device of any of the foregoing embodiments.

[0035] In a fourth aspect, the embodiments of the present application further provide an energy storage system, which comprises an energy storage converter and the energy storage device, and the energy storage converter is used to electrically connect a power generation device and the energy storage device.

[0036] In a fifth aspect, the embodiments of the present application further provide a charging network, which comprises a charging pile and the energy storage device, and the energy storage device is used to provide electric energy for the charging pile.

[0037] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. 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 skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0039] Figure 1 The structure schematic diagram of the charging network in some embodiments of the present application;

[0040] Figure 2 The structure schematic diagram of the energy storage system in some embodiments of the present application;

[0041] Figure 3 A structural schematic diagram of an energy storage device in some embodiments of the present application;

[0042] Figure 4 A structural schematic diagram of an energy storage device in some embodiments of the present application;

[0043] Figure 5 A structural schematic diagram of an energy storage device in some embodiments of the present application;

[0044] Figure 6 A structural schematic diagram of an energy storage device in some embodiments of the present application;

[0045] Figure 7 A structural schematic diagram of a second insulating member in a battery cell in some embodiments of the present application;

[0046] Figure 8 A structural schematic diagram of a second insulating member in a battery cell in some embodiments of the present application;

[0047] Figure 9 A structural schematic diagram of a second insulating member in a battery cell in some embodiments of the present application;

[0048] Figure 10 A structural schematic diagram of a second insulating member in a battery cell in some embodiments of the present application;

[0049] Figure 11 A structural schematic diagram of a second insulating member in a battery cell in some embodiments of the present application;

[0050] Figure 12 A structural schematic diagram of a second insulating member in a battery cell in some embodiments of the present application;

[0051] Icon: 1000 - charging network; 2000 - energy storage system; 3000 - power generation device; 100 - battery device; 200 - energy storage device; 210 - energy storage box; 300 - charging pile; 400 - energy storage converter; 10 - box; 11 - first sub-box; 12 - second sub-box; 20 - battery monomer; 21 - shell; 211 - shell; 212 - end cover assembly; 213 - first wall; 214 - third insulation piece; 215 - pressure relief mechanism; 22 - electrode assembly; 221 - main body part; 2211 - third end; 2212 - fourth end; 222 - first tab; 223 - second tab; 23 - electrode terminal; 231 - first electrode terminal; 232 - second electrode terminal; 24 - first insulation piece; 241 - first part; 25 - second insulation piece; 251 - body; 2511 - first through hole; 2512 - fourth through hole; 252 - bending part; 2521 - positioning hole; 2522 - first end; 2523 - second end; 253 - transition part; 2531 - second through hole; 254 - third through hole; 26 - second opening; 27 - first adapter; 28 - second adapter; X - first direction; Y - second direction; Z - third direction. DETAILED DESCRIPTION

[0052] 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 of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0053] 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 of the present application, 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, and are not intended to describe a particular order or primary and secondary relationship.

[0054] Reference within this application to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. As used in this application, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless specified otherwise, or clear from context, "X employs A or B" means that X employs A or B or both. In addition, the term "another" is used interchangeably with "one or more". As used in this application, the term "another" is intended to mean "at least one" or "one or more", unless specified otherwise.

[0055] In the description of the application, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mount", "connect", "connection", "attach" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0056] In this application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three kinds of 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 this application generally represents that the front and rear associated objects have an "or" relationship.

[0057] In this application, "multiple" means two or more (including two), and similarly, "multiple groups" means two or more groups (including two groups), and "multiple pieces" means two or more pieces (including two pieces).

[0058] The battery device mentioned in the embodiments of the 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, in parallel, or in a hybrid manner through a busbar component.

[0059] In some embodiments, the battery cell assembly is generally 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.

[0060] In some embodiments, the battery device 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.

[0061] 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.

[0062] As an example, the battery cell assembly can also be housed in the case by directly fixing a plurality of battery cells to the case.

[0063] In some embodiments, the case can be part of a chassis structure of a vehicle. For example, part of the case can be at least part of a floor of the vehicle, or part of the case can be at least part of a cross beam and a longitudinal beam of the vehicle.

[0064] In some embodiments, the battery device can be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0065] In the 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.

[0066] 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.

[0067] 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 process of the battery cell, active ions (such as lithium ions) are embedded and extracted between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can prevent the positive and negative electrodes from short-circuiting, and at the same time allow the active ions to pass through.

[0068] 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 arranged on at least one surface of the positive electrode current collector.

[0069] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction of itself, and the positive electrode active material is arranged on any one or both of the two opposite surfaces of the positive electrode current collector.

[0070] As an example, the positive electrode current collector can adopt a metal foil or a composite current collector. For example, as a metal foil, stainless steel, stainless steel, copper, aluminum, carbon electrode, carbon, nickel, or titanium, etc. with silver plating treatment on the surface can be used. The composite current collector can include a high polymer 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 polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0071] As an example, the positive electrode active material can include at least one of lithium-containing phosphates, lithium transition metal oxides, and modified compounds of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a positive electrode active material of a battery cell can also be used.

[0072] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0073] As an example, the negative electrode current collector can employ a metal foil or a composite current collector. For example, as a 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, titanium, or the like can be employed.

[0074] 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.

[0075] 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, lithium titanate, and 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 of a battery cell can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0076] 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.

[0077] 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 separator 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.

[0078] 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.

[0079] In some embodiments, the electrode assembly is a wound structure. The positive electrode sheet and the negative electrode sheet are wound to form the wound structure.

[0080] In some embodiments, the electrode assembly is a stacked structure.

[0081] In some embodiments, the battery cell can include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing 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.

[0082] In some embodiments, the housing 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 the 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.

[0083] In some embodiments, at least one electrode terminal is provided on the housing, 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.

[0084] In some embodiments, an explosion-proof valve is provided on the housing. The explosion-proof valve is used to release the internal pressure of the battery cell.

[0085] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of other shapes, including a square battery cell, a blade battery cell, a multi-prismatic battery cell (such as a hexagonal battery cell), etc., without specific limitation in the embodiments of the present application.

[0086] In battery technology, a large part of the fire accidents of electric vehicles is caused by thermal runaway of the battery. The existing insulating member of the battery cell is wrapped around the bottom surface and the peripheral surface area of the electrode assembly, and the upper end of the insulating member is connected to the lower plastic of the end cap by heat fusion. The insulating member occupies a large area of the electrode assembly, the side surface and the bottom surface. When the battery cell experiences thermal runaway, the large space occupied by the insulating member is not conducive to the discharge of gas, affecting the safety of the battery cell.

[0087] In view of this, to improve the safety of the battery monomer, some embodiments of the battery monomer provided by the application include a shell, an electrode assembly, a first insulating piece and a second insulating piece, the shell includes a shell body and an end cover assembly, the shell body has a first opening, and the end cover assembly seals the first opening; the electrode assembly is arranged in the shell body, and the electrode assembly includes a main body part and a first tab, the end cover assembly is located on one side of the main body part along a first direction, the main body part has a first end face facing the end cover assembly, and the first tab extends from the first end face; the first insulating piece covers the outer circumferential surface of the main body part, and the first insulating piece has a first part corresponding to the largest area of the outer surface of the main body part; along the first direction, one end of the second insulating piece is connected with the end cover assembly, and the other end of the second insulating piece is connected with the first part; along a second direction, the second insulating piece is located between the first tab and the shell body, and the orthographic projection of the second insulating piece covers the orthographic projection of the first tab on the same projection plane perpendicular to the second direction; the orthographic projection of the second insulating piece does not block the orthographic projection of the main body part on the same projection plane perpendicular to a third direction, the third direction, the second direction and the first direction are perpendicular to each other, and the second direction is parallel to the thickness direction of the electrode assembly.

[0088] The battery monomer provided by the embodiments of the application can separate the first tab and the inner wall of the shell body, reduce the risk of short circuit caused by the first tab lapping the shell body in the second direction, and insulate and protect the first tab. The first insulating piece covers the outer circumferential surface of the electrode assembly and can not cover the bottom side of the electrode assembly, and the orthographic projection of the second insulating piece does not block the orthographic projection of the main body part along the third direction. The second insulating piece does not cover the side surface area of the main body part except the large surface, so that the exhaust gap is formed between the bottom surface of the electrode assembly and the shell body, and between the side surface of the electrode assembly close to the second insulating piece and the second insulating piece. When the battery monomer is in thermal runaway, the exhaust gap can provide an exhaust passage for the gas flow in the shell body, which is more conducive to the smooth exhaust of the gas, increases the exhaust path, and improves the safety of the battery monomer.

[0089] The battery device disclosed by the embodiments of the application can be applied to energy storage devices such as energy storage containers or energy storage cabinets.

[0090] The battery device will be described below with reference to the accompanying drawings.

[0091] Please refer to Figure 1 and Figure 3 , Figure 1 The structural diagram of the charging network provided by some embodiments of the application is shown in Figure 3A structural schematic diagram of an energy storage device is provided for some embodiments of the present application. An embodiment of the present application provides a charging network 1000, which includes a charging pile 300 for charging an electric device. The charging network 1000 can also include an energy storage device 200, which is electrically connected to the charging pile 300, and the energy storage device 200 is configured to provide electric energy for the charging pile 300.

[0092] It should be noted that the charging pile 300 is electrically connected to the battery cell in the energy storage device 200 through a cable, and the battery cell can provide the stored electric energy to the charging pile 300. The charging pile 300 has a connector, which can be connected to the electric device, so as to charge the electric device. The charging network 1000 applies the energy storage device 200, which can effectively improve the safety of the charging network 1000, and also helps to improve the flexibility of the charging network 1000 when deployed.

[0093] In one charging network 1000, the charging pile 300 can be one, and the energy storage device 200 provides electric energy for the charging pile 300; the charging pile 300 can also be multiple, and the energy storage device 200 provides electric energy for multiple charging piles 300.

[0094] As an example, as shown in Figure 1 , the charging network 1000 includes one energy storage device 200 and two charging piles 300, and one energy storage device 200 provides electric energy for two charging piles 300.

[0095] The energy storage device 200 can include a battery device 100, which is electrically connected to the charging pile 300, so as to provide electric energy for the charging pile 300.

[0096] Please refer to Figure 2 and Figure 3 , Figure 2 A structural schematic diagram of an energy storage system is provided for some embodiments of the present application. An embodiment of the present application provides an energy storage system 2000, which includes an energy storage converter 400, which can be electrically connected to a power generation device 3000 to convert the electric power provided by the power generation device 3000. The energy storage system 2000 can also include an energy storage device 200, which is electrically connected to the energy storage converter 400, and the energy storage converter 400 converts the electric energy provided by the power generation device 3000 and then introduces it into the energy storage device 200 for storage.

[0097] The power conversion device is used to connect between the power generation device 3000 and the energy storage device 200. The power generation device 3000 is used to generate electric energy, and the power generation device 3000 is used to store the generated electric energy into the energy storage device 200 through the power conversion device. The energy storage system 2000 applies the energy storage device 200, which can effectively improve the operation safety of the energy storage system 2000. In specific implementation, the power generation equipment can be a solar panel, a hydroelectric power generation equipment, a thermal power generation equipment, etc. The specific type of the power generation equipment is not limited in the present application.

[0098] As an example, as shown in Figure 2 , the energy storage system 2000 includes an energy storage device 200 and an energy storage converter 400, and two power generation devices 3000 respectively transmit the generated electric energy to the energy storage converter 400, and the electric energy is introduced into the energy storage device 200 through the energy storage converter 400 for storage.

[0099] Please refer to Figure 3 , the energy storage device 200 includes an energy storage box 210, and the battery device 100 is arranged in the energy storage box 210.

[0100] As an example, the energy storage device 200 can be an energy storage container, an energy storage cabinet, etc.

[0101] As an example, the energy storage device 200 can be used for energy storage power station, wind power generation system, solar power generation system, mobile power system or temporary power supply system, etc. The energy storage power station can store electric energy when the electricity consumption is low, and provide electric energy for related users or electric equipment when the electricity consumption is high. The wind turbine generator set of the wind power generation system collects wind energy and converts it into electric energy, which is stored by the energy storage device 200. The solar power generation system can convert solar energy into electric energy, which is stored by the energy storage device 200 and supplied to users in time. The mobile power system can supply power to related electric equipment in places where the power grid power supply system cannot reach, such as remote mountainous areas and remote wild areas. The temporary power supply system can supply power to users in the case of insufficient power supply.

[0102] Please refer to Figure 4 , Figure 4A structural exploded view of a battery device is provided for some embodiments of the present application. The battery device 100 includes a case 10 and battery cells 20, which are accommodated in the case 10. The case 10 is configured to provide an accommodation space for the battery cells 20, and the case 10 can have various structures. In some embodiments, the case 10 can include a first sub-case 11 and a second sub-case 12, the first sub-case 11 and the second sub-case 12 are coupled to each other, and the first sub-case 11 and the second sub-case 12 together define an accommodation space for accommodating the battery cells 20. The second sub-case 12 can be a hollow structure with one open end, and the first sub-case 11 can be a plate structure, which is coupled to the open end of the second sub-case 12 to define the accommodation space together with the second sub-case 12. Alternatively, the first sub-case 11 and the second sub-case 12 can both be hollow structures with one open end, and the open end of the first sub-case 11 is coupled to the open end of the second sub-case 12.

[0103] 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. Alternatively, the multiple battery cells 20 can be first connected in series, in parallel, or in a mixed manner to form battery modules, and the multiple battery modules are connected in series, in parallel, or in a mixed manner to form a whole, which is accommodated in the case 10.

[0104] The battery device 100 can further include other structures. For example, the battery device 100 can further include a busbar for electrically connecting the multiple battery cells 20.

[0105] Please refer to Figure 5 , Figure 5 An exploded view of a battery cell is provided for 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 shell 211 and an end cap assembly 212, the shell 211 has an opening, and the end cap assembly 212 closes the opening to isolate the internal environment of the battery cell 20 from the external environment.

[0106] The shell 211 is a component configured to cooperate with the end cap assembly 212 to form an internal environment of the battery cell 20, and the internal environment is configured to accommodate the electrode assembly 22, electrolyte, and other components. The shell 211 and the end cap assembly 212 can be independent components. The shell 211 can have various shapes and sizes. Specifically, the shape of the shell 211 can be determined according to the specific shape and size of the electrode assembly 22. The shell 211 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0107] The end cover assembly 212 refers to a component that covers the opening of the housing 211 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cover assembly 212 can be adapted to the shape of the housing 211 to fit the housing 211. Optionally, the end cover assembly 212 can be made of a material with certain hardness and strength, such as aluminum alloy, so that the end cover assembly 212 is not easily deformed when subjected to extrusion collision, so that the battery cell 20 can have higher structural strength, and the reliability can also be improved. The end cover assembly 212 can be provided with functional components such as the electrode terminal 23. The end cover assembly 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 electric energy of the battery cell 20. The material of the end cover assembly 212 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the present application does not make special limitations on this.

[0108] The electrode assembly 22 is a component in which an electrochemical reaction occurs in the battery cell 20. The housing 211 can contain one or more electrode assemblies 22.

[0109] The present application provides a battery cell, please refer to Figure 5 and Figure 6 , Figure 5 The explosion schematic diagram of the battery cell in the battery device provided by some embodiments of the present application, Figure 6A structural schematic diagram of a battery cell in a battery device provided for some embodiments of the present application. The battery cell 20 includes a housing 21, an electrode assembly 22, a first insulating member 24, and a second insulating member 25. The housing 21 includes a shell 211 and an end cap assembly 212, the shell 211 has a first opening, and the end cap assembly 212 closes the first opening. The electrode assembly 22 is disposed in the shell 211, and the electrode assembly 22 includes a main body 221 and a first tab 222. The end cap assembly 212 is located at one side of the main body 221 along a first direction X. The main body 221 has a first end face facing the end cap assembly 212, and the first tab 222 extends from the first end face. The first insulating member 24 covers an outer circumferential surface of the main body 221, and the first insulating member 24 has a first portion 241 corresponding to an outer surface of the main body 221 with the largest area. Along the first direction X, one end of the second insulating member 25 is connected to the end cap assembly 212, and the other end of the second insulating member 25 is connected to the first portion 241. Along a second direction Y, the second insulating member 25 is located between the first tab 222 and the shell 211. In the same projection plane perpendicular to the second direction Y, the orthogonal projection of the second insulating member 25 covers the orthogonal projection of the first tab 222. In the same projection plane perpendicular to a third direction Z, the orthogonal projection of the second insulating member 25 does not block the orthogonal projection of the main body 221. The third direction Z, the second direction Y, and the first direction X are perpendicular to each other, and the second direction Y is parallel to the thickness direction of the electrode assembly 22.

[0110] The housing 21 includes the shell 211 and the end cap assembly 212. The shell 211 is a component for cooperating with the end cap assembly 212 to form an internal environment of the battery cell. The internal environment formed by the shell 211 can be used to accommodate the electrode assembly 22, electrolyte, and other components. The first opening refers to an open structure of the shell 211. The end cap assembly 212 is arranged at the first opening of the shell 211, and the end cap assembly 212 closes the first opening.

[0111] The electrode assembly 22 is a component in which electrochemical reactions occur in the battery cell. The shell 211 can contain one or more electrode assemblies 22. The main body 221 refers to the main body 221 of the electrode assembly 22. The first tab 222 extends from the first end face of the main body 221.

[0112] The first insulating member 24 covers the outer circumferential surface of the main body portion 221, that is, the first insulating member 24 only covers the outer circumferential surface of the main body portion 221 of the electrode assembly 22, and the first insulating member 24 does not cover the area of the top surface and the bottom surface of the main body portion 221. The first portion 241 refers to the portion of the first insulating member 24 corresponding to the outer surface with the largest area of the battery cell, that is, the large surface of the battery cell, and it can also be understood that the first portion 241 refers to the portion of the first insulating member 24 corresponding to the large surface of the battery cell. The material of the first insulating member 24 can be a polyester film, that is, a Mylar film.

[0113] The second insulating member 25 refers to the insulating member arranged on the first end surface of the electrode assembly 22. In the first direction X, one end of the second insulating member 25 is connected with the end cover assembly 212, and the other end extends to the first portion 241 and is connected with the first portion 241. In the second direction Y, the second insulating member 25 is located between the first tab 222 and the shell 211. In the same projection plane perpendicular to the second direction Y, the orthographic projection of the second insulating member 25 covers the orthographic projection of the first tab 222. In the second direction Y, a portion of the second insulating member 25 is located between the second tab 223 and the shell 211. The second insulating member 25 can play an insulating role between the first tab 222 and the inner wall of the shell 211. The material of the second insulating member 25 can be different from that of the first insulating member 24.

[0114] In the technical scheme of the embodiment of the present application, the first insulating member 24 covers the outer circumferential surface of the main body portion 221, and the first insulating member 24 can play an insulating role between the outer circumferential surface of the electrode assembly 22 and the inner wall of the shell 211. In the second direction Y, the second insulating member 25 is located between the first tab 222 and the shell 211. In the same projection plane perpendicular to the second direction Y, the orthographic projection of the second insulating member 25 covers the orthographic projection of the first tab 222. The second insulating member 25 can separate the first tab 222 and the inner wall of the shell 211, reduce the risk of short circuit caused by the overlap of the first tab 222 and the shell 211 in the second direction Y, and play an insulating protection role for the first tab 222. Moreover, the first insulating member 24 covers the outer circumferential surface of the electrode assembly 22, and can not cover the bottom surface side of the electrode assembly 22. In the third direction Z, the orthographic projection of the second insulating member 25 does not block the orthographic projection of the main body portion 221. The second insulating member 25 does not cover the side surface area of the main body portion 221 except the large surface, so that the bottom surface of the electrode assembly 22 and the shell 211, and the part of the side surface of the electrode assembly 22 close to the second insulating member 25 and the second insulating member 25 form exhaust gaps. When the battery cell is in thermal runaway, the exhaust gaps can provide an exhaust passage for the gas flow in the shell 211, which is more conducive to the smooth exhaust of the gas, increases the exhaust path, and improves the safety of the battery cell 20.

[0115] According to some embodiments of the present application, the orthographic projection of the first insulating member 24 surrounds the orthographic projection of the main body portion 221.

[0116] The orthographic projection of the first insulating member 24 surrounds the orthographic projection of the main body portion 221, the first insulating member 24 covers the outer circumferential surface of the main body portion 221 and does not cover the bottom surface side of the main body portion 221, so that the bottom surface of the electrode assembly 22 and the shell 211 can form an exhaust gap, which is beneficial to the smooth exhaust of gas when the battery monomer 20 is in thermal runaway.

[0117] According to some embodiments of the present application, please refer to Figures 7 to 10 , Figure 7 the structure diagram of the second insulating member in the battery monomer provided by some embodiments of the present application, Figure 8 the structure diagram of the second insulating member in the battery monomer provided by some embodiments of the present application, Figure 9 the structure diagram of the second insulating member in the battery monomer provided by some embodiments of the present application, Figure 10 the structure diagram of the second insulating member in the battery monomer provided by some embodiments of the present application. The second insulating member 25 comprises a body 251 and two bending portions 252 connected with each other, the body 251 is arranged between the end cover assembly 212 and the main body portion 221 and connected with the end cover assembly 212, along the first direction X, the body 251 at least partially overlaps with the first end surface, the body 251 has a first through hole 2511 avoiding the first tab 222, the two bending portions 252 are arranged at intervals along the second direction Y, the body 251 is located between the two bending portions 252, along the second direction Y, the bending portion 252 is located between the body 251 and the shell 211; the first insulating member 24 has two first portions 241, the two first portions 241 are arranged at intervals along the second direction Y, the two bending portions 252 are respectively arranged corresponding to the two first portions 241, the end of the bending portion 252 away from the body 251 along the first direction X is connected with the corresponding first portion 241; on the same projection plane perpendicular to the second direction Y, the orthographic projection of the bending portion 252 covers the orthographic projection of the first tab 222.

[0118] The body 251 is arranged between the end cover assembly 212 and the main body portion 221 and connected with the end cover assembly 212, the body 251 refers to the main body portion 221 of the second insulating member 25, that is, the part corresponding to the first end surface of the main body portion 221, along the first direction X, the body 251 is located between the end cover assembly 212 and the main body portion 221. The connection mode between the body 251 and the end cover assembly 212 can be various, the body 251 and the end cover assembly 212 can be connected by adhesion or hot melting, and the specific connection mode can be determined according to the actual situation.

[0119] In the first direction X, the body 251 at least partially overlaps the first end surface, the body 251 has a first through hole 2511 avoiding the first tab 222, that is, the body 251 covers at least part of the first end surface, and the body 251 covers at least the first tab 222, and the first through hole 2511 formed on the body 251 can be used to avoid the first tab 222.

[0120] The bending part 252 refers to a bending structure on the second insulating piece 25 that can be bent relative to the body 251, one end of the bending part 252 is connected to the body 251, and the other end of the bending part 252 is lapped on the main body part 221 of the electrode assembly 22. The two bending parts 252 are spaced apart in the second direction Y, and the body 251 is located between the two bending parts 252, that is, the two bending parts 252 are respectively arranged at the two ends of the body 251 in the second direction Y, and the two bending parts 252 are respectively connected to the two ends of the body 251 in the second direction Y, that is, the shape of the second insulating piece 25 is in a U-shaped structure.

[0121] In the same projection plane perpendicular to the second direction Y, the orthographic projection of the bending part 252 covers the orthographic projection of the first tab 222, that is, the second insulating piece 25 can shield the first tab 222 through the bending part 252, in the second direction Y, the bending part 252 plays a role of isolation between the first tab 222 and the inner wall of the shell 211, preventing the first tab 222 from contacting the inner wall of the shell 211, thereby playing a role of insulating protection for the first tab 222.

[0122] The second insulating piece 25 is used as the body 251 and the two bending parts 252, the body 251 is arranged between the end cover assembly 212 and the main body part 221 and connected to the end cover assembly 212, in the second direction Y, the bending part 252 is located between the body 251 and the shell 211, the two bending parts 252 correspond to the two first parts 241 of the electrode assembly 22 respectively, in the same projection plane perpendicular to the second direction Y, the orthographic projection of the bending part 252 covers the orthographic projection of the first tab 222, and the second insulating piece 25 realizes the insulation between the two sides of the first tab 222 in the second direction Y and the shell 211 through the two bending parts 252, reduces the risk of short circuit of the first tab 222 lapping with the shell 211 in the second direction Y, and improves the safety of the battery monomer 20.

[0123] According to some embodiments of the present application, please refer to Figure 6 , Figure 6 The structure of the battery monomer in the battery device provided by some embodiments of the present application is shown in the schematic diagram. The second insulating piece 25 and the electrode assembly 22 enclose an accommodation space, and the two ends of the accommodation space in the third direction Z form second openings 26.

[0124] The second opening 26 is an open structure of an accommodation space formed between the second insulating member 25 and the electrode assembly 22. In addition to the body 251 and the two bending portions 252 described above, in other embodiments, only the two bending portions 252 can be provided, which are spaced apart along the second direction Y and can also form the second opening 26 in the third direction Z.

[0125] With the provision of the second opening 26 in the accommodation space formed by the second insulating member 25 and the electrode assembly 22, when the battery cell is in thermal runaway, gas can enter from the second opening 26 and finally be discharged from the pressure relief mechanism 215 of the end cover assembly 212, increasing the exhaust gap for gas discharge.

[0126] According to some embodiments of the present application, please continue to refer to Figure 6 The bending portion 252 has a first end 2522 and a second end 2523 along the third direction Z, and the main body portion 221 has a third end 2211 and a fourth end 2212 along the third direction Z, the first end 2522 and the third end 2211 are correspondingly arranged, and the second end 2523 and the fourth end 2212 are correspondingly arranged, the first end 2522 and the third end 2211 have a first gap therebetween, and the second end 2523 and the fourth end 2212 have a second gap therebetween.

[0127] The bending portion 252 has a first end 2522 and a second end 2523 along the third direction Z, and the main body portion 221 has a third end 2211 and a fourth end 2212 along the third direction Z, the first end 2522 and the third end 2211 are correspondingly arranged, and the second end 2523 and the fourth end 2212 are correspondingly arranged, the first end 2522 and the third end 2211 have a first gap therebetween, and the second end 2523 and the fourth end 2212 have a second gap therebetween.

[0128] The first end 2522 and the third end 2211 have a gap therebetween, which means that the first end 2522 and the third end 2211 are spaced apart along the third direction Z, and the first end 2522 and the third end 2211 have a spacing therebetween. The second end 2523 and the fourth end 2212 have a second gap therebetween, which means that the second end 2523 and the fourth end 2212 are spaced apart along the third direction Z, and the second end 2523 and the fourth end 2212 have a spacing therebetween. The first gap and the second gap can be equal or not equal. In this embodiment, the first gap and the second gap are equal.

[0129] The first end 2522 of the bending portion 252 and the third end 2211 have a first gap in the third direction Z, and the second end 2523 and the fourth end 2212 have a second gap. The bending portion 252 of the second insulating member 25 does not need to completely cover the main body portion 221 in the third direction Z, and the second insulating member 25 can insulate and protect the first tab 222. The length of the bending portion 252 of the second insulating member 25 in the third direction Z is reduced, and the material is less used. In addition, the first gap and the second gap between the bending portion 252 and the main body portion 221 can form an exhaust gap. When the battery monomer is in thermal runaway, the exhaust gap and the exhaust path increase the gas flow, allowing the gas to be discharged more smoothly, and improving the safety of the battery monomer 20.

[0130] According to some embodiments of the present application, please continue to refer to Figure 6 and Figure 7 , Figure 6 the structure diagram of the battery monomer in the battery device provided by some embodiments of the present application, Figure 7 the structure diagram of the second insulating member in the battery monomer provided by some embodiments of the present application. The bending portion 252 is provided with a positioning hole 2521. In the same projection plane perpendicular to the second direction Y, the orthographic projection of the positioning hole 2521 does not overlap with the orthographic projection of the first tab 222, and the orthographic projection of the positioning hole 2521 does not overlap with the orthographic projection of the main body portion 221.

[0131] The positioning hole 2521 refers to a through hole structure penetrating through the thickness direction of the bending portion 252. The orthographic projection of the positioning hole 2521 does not overlap with the orthographic projection of the first tab 222, and the orthographic projection of the positioning hole 2521 does not overlap with the orthographic projection of the main body portion 221. The position of the positioning hole 2521 is not coincident with the position of the main body portion 221 and the first tab 222 of the electrode assembly 22, and the positioning hole 2521 can avoid the main body portion 221 and the first tab 222.

[0132] The number of positioning holes 2521 can be one or more, and the number of positioning holes 2521 can be determined according to actual conditions.

[0133] By setting the positioning hole 2521 on the bending part 252, on the one hand, the positioning hole 2521 is convenient for the second insulating part 25 to be positioned and used with the tooling fixture during assembly, facilitating the assembly and positioning of the battery monomer. On the other hand, by making the orthographic projection of the positioning hole 2521 not overlap the orthographic projection of the first tab 222, and the orthographic projection of the positioning hole 2521 not overlap the orthographic projection of the main body part 221, the positioning hole 2521 on the bending part 252 can avoid the positions of the main body part 221 of the electrode assembly 22 and the first tab 222. When the battery monomer is in thermal runaway, the positioning hole 2521 increases the exhaust passage of the gas in the battery monomer, and the positioning hole 2521 is staggered with the position of the first tab 222. When the gas in the battery monomer passes through the positioning hole 2521 and is discharged, it will not impact the tab, thereby improving the safety of the battery monomer 20.

[0134] According to some embodiments of the present application, the number of positioning holes 2521 is multiple, and the multiple positioning holes 2521 are arranged at intervals along the third direction Z.

[0135] The number of positioning holes 2521 can be two, three, or four, etc. In the present embodiment, the number of positioning holes 2521 is two, and the two positioning holes 2521 are distributed at intervals along the third direction Z.

[0136] The number of positioning holes 2521 is set to multiple, and the multiple positioning holes 2521 are distributed at intervals. When the second insulating part 25 is assembled and positioned, the corresponding positioning hole 2521 is selected to be assembled and positioned with the tooling fixture, thereby improving the positioning accuracy. Moreover, the multiple positioning holes 2521 also increase the number of exhaust passages. When the battery monomer 20 is in thermal runaway, the exhaust is more smooth, and the safety of the battery monomer 20 is higher.

[0137] According to some embodiments of the present application, please refer to Figure 9 , Figure 9 The present application provides a structure schematic diagram of the bending part and the body before being bent in the second insulating part. The bending part 252 is connected with the body 251 through the transition part 253, and the transition part 253 is provided with multiple second through holes 2531 at intervals along the third direction Z.

[0138] The transition part 253 refers to the joint part between the bending part 252 and the body 251, and the second through hole 2531 refers to the through hole structure provided on the transition part 253. The second through hole 2531 can be a rectangular hole or a circular hole, etc. In the present embodiment, the second through hole 2531 is a rectangular hole.

[0139] The multiple second through holes 2531 are distributed at intervals along the extension direction of the transition part 253, that is, the multiple second through holes 2531 are distributed at intervals along the third direction Z on the transition part 253.

[0140] The plurality of second through holes 2531 arranged on the transition portion 253 in the third direction Z can reduce the bending strength of the transition portion 253, and the bending portion 252 can be easily bent and deformed relative to the body 251 after being subjected to an external force, so that the bending portion 252 can be bent relative to the body 251, and the bending portion 252 can be connected to the first portion 241 of the first insulating member 24.

[0141] According to some embodiments of the present application, the length of the second through hole 2531 in the third direction Z is L1, and 0.8mm≤L1≤1.2mm is satisfied; and / or, the distance between adjacent two second through holes 2531 in the third direction Z is L2, and 0.8mm≤L2≤1.2mm is satisfied.

[0142] The length of the second through hole 2531 is 0.8mm-1.2mm, for example, the length of the second through hole 2531 can be 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1.0mm, 1.1mm or 1.2mm, etc., and the specific value of the length of the second through hole 2531 can be determined according to the actual situation. The distance between adjacent two second through holes 2531 is 0.8mm-1.2mm, for example, L2 can be 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1.0mm, 1.1mm or 1.2mm, etc., and the specific value of L2 can be determined according to the actual situation.

[0143] The length of the second through hole 2531 is limited to 0.8mm-1.2mm, which can not only ensure the strength of the transition portion 253, but also facilitate the folding of the bending portion 252 relative to the body 251. If the length of the second through hole 2531 is less than 0.8mm, the bending strength of the transition portion 253 is relatively large, which is not conducive to the folding of the bending portion 252. If the length of the second through hole 2531 is greater than 1.2mm, the size of the second through hole 2531 is too large, which affects the strength of the transition portion 253, thereby affecting the structural strength of the bending portion 252 of the second insulating member 25. Similarly, the distance between adjacent two second through holes 2531 is limited to 0.8mm-1.2mm, which can not only ensure the strength of the transition portion 253, but also facilitate the folding of the bending portion 252. If the distance between adjacent two second through holes 2531 is less than 0.8mm, the plurality of second through holes 2531 on the transition portion 253 are distributed relatively densely, which affects the strength of the transition portion 253, thereby affecting the structural strength of the bending portion 252 of the second insulating member 25. If the distance between adjacent two second through holes 2531 is greater than 1.2mm, the plurality of second through holes 2531 are distributed relatively dispersedly, and the bending strength of the transition portion 253 is relatively large, which is not conducive to the folding of the bending portion 252.

[0144] According to some embodiments of the present application, the thickness of the second insulation member 25 is 0.03mm-0.2mm.

[0145] The thickness of the second insulation member 25 is 0.03mm-0.2mm, for example, the thickness of the second insulation member 25 can be 0.03mm, 0.05mm, 0.07mm, 0.09mm, 0.1mm, 0.12mm, 0.15mm or 0.2mm, etc., the thickness of the second insulation member 25 can be determined according to actual conditions.

[0146] The thickness of the second insulation member 25 is limited to 0.03mm-0.2mm, which can not only ensure the structural strength of the second insulation member 25, but also facilitate the forming quality of the second insulation member 25, and reduce the space occupied by the second insulation member 25 in the thickness direction. If the thickness of the second insulation member 25 is less than 0.03mm, the thickness of the second insulation member 25 is small, and the strength of the second insulation member 25 is relatively small, which affects the connection strength of the second insulation member 25. If the thickness of the second insulation member 25 is greater than 0.2mm, the strength value of the second insulation member 25 is redundant, and the space occupied by the second insulation member 25 is larger, which is not conducive to the space layout of the electrode assembly 22 and the end cover assembly 212 inside the shell 211.

[0147] According to some embodiments of the present application, please refer to Figure 12 , Figure 12 The partial cross-sectional view of the electrode assembly and the end cover assembly in the battery cell provided by some embodiments of the present application. The end cover assembly 212 includes a first wall 213, a third insulation member 214 and a first electrode terminal 231, the first electrode terminal 231 is arranged on the first wall 213, the third insulation member 214 is connected with the first wall 213, and the third insulation member 214 is located between the first wall 213 and the body 251, and the body 251 is connected with the third insulation member 214.

[0148] The third insulation member 214 is also the lower plastic of the end cover assembly 212, and the third insulation member 214 plays an insulation function, and the third insulation member 214 is located between the first wall 213 and the body 251, that is, along the first direction X, the body 251, the third insulation member 214 and the first wall 213 are distributed in sequence. The connection between the body 251 and the third insulation member 214 can be connected by hot melting or adhesion, and optionally, the body 251 and the third insulation member 214 are hot melting connected.

[0149] The third insulation piece 214 is arranged between the second insulation piece 25 and the first wall 213, and the third insulation piece 214 plays an insulating role in the end cover assembly 212, reduces the risk of short circuit caused by the first tab 222 and the first wall 213 being overlapped, and plays a fixing role in the second insulation piece 25 through the body 251 and the third insulation piece 214, thereby improving the installation stability of the second insulation piece 25.

[0150] According to some embodiments of the present application, the battery monomer further comprises a first adapter 27, and the first tab 222 is connected to the first electrode terminal 231 through the first adapter 27; and along the first direction X, part of the second insulation piece 25 is arranged between the third insulation piece 214 and the first adapter 27.

[0151] The first adapter 27 refers to a connecting structure for connecting the first tab 222 and the first electrode terminal 231. Of course, the electrode assembly 22 can further comprise a second tab 223, the first tab 222 and the second tab 223 are located on the same side of the electrode assembly 22 along the first direction X, and the first tab 222 and the second tab 223 are spaced apart along the third direction Z on the first end face. The battery monomer further comprises a second adapter 28, and the end cover assembly 212 further comprises a second electrode terminal 232, the second electrode terminal 232 is arranged on the first wall 213, the second adapter 28 corresponds to the second tab 223, and the second tab 223 is connected to the second electrode terminal 232 through the second adapter 28. Along the first direction X, part of the second insulation piece 25 is arranged between the third insulation piece 214 and the second adapter 28, and the body 251 has a fourth through hole 2512 avoiding the second tab 223.

[0152] The arrangement of the first adapter 27 facilitates the connection of the first tab 222 to the first electrode terminal 231 through the first adapter 27. Along the first direction X, the first adapter 27 and the third insulation piece 214 are respectively located on the two sides of the second insulation piece 25, the first adapter 27 can clamp and position the second insulation piece 25 with the third insulation piece 214 of the end cover assembly 212, so that the installation stability of the second insulation piece 25 is higher.

[0153] According to some embodiments of the present application, please refer to Figure 11 , Figure 11 The second insulation piece provided in some embodiments of the present application cooperates with the structure of the end cover assembly. The end cover assembly 212 further comprises a pressure relief mechanism 215, and the second insulation piece 25 has a third through hole 254 for avoiding the pressure relief mechanism 215.

[0154] The pressure relief mechanism 215 is also the explosion-proof valve of the battery monomer, and the size and shape of the third through hole 254 are matched with the shape and size of the pressure relief mechanism 215.

[0155] By arranging the third through hole 254 on the second insulation piece 25, the third through hole 254 can play a function of avoiding the pressure relief mechanism 215 on the end cover assembly 212, reducing the phenomenon of assembly interference, and not affecting the normal work of the pressure relief mechanism 215.

[0156] In some embodiments, referring to Figures 5 to 12 , the battery cell 20 includes a shell 21, an electrode assembly 22, a first insulation piece 24, and a second insulation piece 25. The shell 21 includes a shell body 211 having a first opening and an end cover assembly 212 sealing the first opening. The electrode assembly 22 is arranged in the shell body 211 and includes a main body 221 and a first tab 222. The end cover assembly 212 is located on one side of the main body 221 along a first direction X. The main body 221 has a first end face facing the end cover assembly 212, and the first tab 222 extends from the first end face. The first insulation piece 24 covers an outer circumferential surface of the main body 221 and has a first portion 241 corresponding to an outer surface of the main body 221 with the largest area. Along the first direction X, one end of the second insulation piece 25 is connected to the end cover assembly 212, and the other end of the second insulation piece 25 is connected to the first portion 241. Along a second direction Y, the second insulation piece 25 is located between the first tab 222 and the shell body 211. On the same projection plane perpendicular to the second direction Y, the orthogonal projection of the second insulation piece 25 covers the orthogonal projection of the first tab 222. The second direction Y is perpendicular to the first direction X and parallel to the thickness direction of the electrode assembly 22. The second insulation piece 25 includes a body 251 and two bending portions 252 connected to each other. The body 251 is arranged between the end cover assembly 212 and the main body 221 and connected to the end cover assembly 212. Along the first direction X, the body 251 at least partially overlaps the first end face. The body 251 has a first through hole 2511 avoiding the first tab 222. The two bending portions 252 are arranged in a spaced manner along the second direction Y. The body 251 is located between the two bending portions 252. Along the second direction Y, the bending portion 252 is located between the body 251 and the shell body 211. The first insulation piece 24 has two first portions 241 arranged in a spaced manner along the second direction Y. The two bending portions 252 are arranged correspondingly to the two first portions 241. An end of the bending portion 252 away from the body 251 along the first direction X is connected to the corresponding first portion 241. On the same projection plane perpendicular to the second direction Y, the orthogonal projection of the bending portion 252 covers the orthogonal projection of the first tab 222.

[0157] The second insulation piece 25 can separate the first tab 222 and the inner wall of the shell 211, reduce the risk of short circuit of the first tab 222 lapping with the shell 211 in the second direction Y, and play an insulation protection role on the first tab 222. Moreover, the first insulation piece 24 covers the outer circumferential surface of the electrode assembly 22, and can not cover the bottom surface side of the electrode assembly 22, and one end of the second insulation piece 25 is connected with the first part 241 of the electrode assembly 22, and along the first direction X, the second insulation piece 25 can not cover the outer circumferential surface of the main body part 221 except the large surface, so that the bottom surface of the electrode assembly 22 and the shell 211, and the side surface of the electrode assembly 22 close to the second insulation piece 25 and the second insulation piece 25 form an exhaust gap, which can provide an exhaust passage for gas flow in the shell 211 when the battery monomer is in thermal runaway, and is more conducive to smooth exhaust of the gas, increases the exhaust path, and improves the safety of the battery monomer. The second insulation piece 25 is adopted as the body 251 and two bending parts 252, the body 251 is arranged between the end cover assembly 212 and the main body part 221 and connected with the end cover assembly 212, along the second direction Y, the bending part 252 is located between the body 251 and the shell 211, and the two bending parts 252 correspond to the two first parts 241 of the electrode assembly 22 respectively, in the same projection plane perpendicular to the second direction Y, the orthographic projection of the bending part 252 covers the orthographic projection of the first tab 222, and the second insulation piece 25 realizes insulation between the two sides of the first tab 222 in the second direction Y and the shell 211 through the two bending parts 252, reduces the risk of short circuit of the first tab 222 lapping with the shell 211 in the second direction Y, and improves the safety of the battery monomer.

[0158] In some embodiments, the bending part 252 has a first end 2522 and a second end 2523 along a third direction Z, the main body part 221 has a third end 2211 and a fourth end 2212 along the third direction Z, the first end 2522 is arranged corresponding to the third end 2211, and the second end 2523 is arranged corresponding to the fourth end 2212, the first end 2522 and the third end 2211 have a first gap therebetween, the second end 2523 and the fourth end 2212 have a second gap therebetween, and the third direction Z, the second direction Y and the first direction X are perpendicular to each other. The bending part 252 is provided with a positioning hole 2521, in the same projection plane perpendicular to the second direction Y, the orthographic projection of the positioning hole 2521 does not overlap the orthographic projection of the first tab 222, and the orthographic projection of the positioning hole 2521 does not overlap the orthographic projection of the main body part 221.

[0159] The first end 2522 of the bending portion 252 and the third end 2211 have a first gap in the third direction Z, and the second end 2523 and the fourth end 2212 have a second gap, under the premise that the second insulating piece 25 can insulate and protect the first tab 222, the bending portion 252 of the second insulating piece 25 does not need to completely cover the main body portion 221 in the third direction Z, thereby reducing the length of the bending portion 252 of the second insulating piece 25 in the third direction Z, and using less material. Moreover, the first gap and the second gap between the bending portion 252 and the main body portion 221 can form an exhaust gap, which increases the exhaust gap and the exhaust path of the gas when the battery monomer is in thermal runaway, so that the gas can be more smoothly discharged, thereby improving the safety of the battery monomer. On the one hand, the positioning hole 2521 facilitates the positioning of the second insulating piece 25 with the tool clamp during assembly, and facilitates the assembly and positioning of the battery monomer. On the other hand, by making the orthographic projection of the positioning hole 2521 not overlap the orthographic projection of the first tab 222, and the orthographic projection of the positioning hole 2521 not overlap the orthographic projection of the main body portion 221, the positioning hole 2521 on the bending portion 252 can avoid the positions of the main body portion 221 of the electrode assembly 22 and the first tab 222, and the positioning hole 2521 increases the exhaust passage of the gas in the battery monomer when the battery monomer is in thermal runaway, and the positioning hole 2521 is staggered with the position of the first tab 222, so that the gas in the battery monomer does not impact the tab when passing through the positioning hole 2521, thereby improving the safety of the battery monomer.

[0160] In some embodiments, the bending portion 252 is connected to the body 251 through a transition portion 253, and the transition portion 253 is provided with a plurality of second through holes 2531 spaced apart in the third direction Z, and the third direction Z, the second direction Y and the first direction X are perpendicular to each other. In the third direction Z, the length of the second through hole 2531 is L1, which satisfies 0.8mm≤L1≤1.2mm; and / or, in the third direction Z, the distance between the adjacent two second through holes 2531 is L2, which satisfies 0.8mm≤L2≤1.2mm.

[0161] The plurality of second through holes 2531 can reduce the bending strength of the transition portion 253, and the bending portion 252 can be easily bent and deformed relative to the body 251 after being subjected to an external force, which can facilitate the bending of the bending portion 252 relative to the body 251, so that the bending portion 252 abuts against and is connected to the first portion 241 of the first insulating piece 24. The length of the second through hole 2531 is limited to 0.8mm-1.2mm, which can not only ensure the strength of the transition portion 253, but also facilitate the folding of the bending portion 252 relative to the body 251. The distance between the adjacent two second through holes 2531 is limited to 0.8mm-1.2mm, which can not only ensure the strength of the transition portion 253, but also facilitate the folding of the bending portion 252.

[0162] Although the present application has been described with reference to preferred embodiments, various modifications can be made to the application without departing from the scope of the application. In particular, the technical features mentioned in the various embodiments can be combined in any way, provided that 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 cell, characterized by, The application relates to a battery, comprising: a shell including a shell body and an end cover assembly, the shell body having a first opening, the end cover assembly closing the first opening; an electrode assembly arranged in the shell body, the electrode assembly including a main body and a first tab, the end cover assembly being located on one side of the main body along a first direction, the main body having a first end face facing the end cover assembly, the first tab extending from the first end face; a first insulating member covering an outer circumferential surface of the main body, the first insulating member having a first portion corresponding to an outer surface of the main body with the largest area; a second insulating member, one end of the second insulating member being connected with the end cover assembly along the first direction, the other end of the second insulating member being connected with the first portion; the second insulating member being located between the first tab and the shell body along a second direction, the second insulating member covering a projection of the first tab on a same projection plane perpendicular to the second direction; a projection of the second insulating member not shielding a projection of the main body on a same projection plane perpendicular to a third direction, the third direction, the second direction and the first direction being perpendicular to each other, and the second direction being parallel to a thickness direction of the electrode assembly.

2. The battery cell of claim 1, wherein, a projection of the first insulating member surrounding a projection of the main body on a same projection plane perpendicular to the first direction.

3. The battery cell of claim 1, wherein, The second insulating member includes a body and two bending portions connected with each other, the body being arranged between the end cover assembly and the main body and connected with the end cover assembly, the body at least partially overlapping the first end face along the first direction, the body having a first through hole avoiding the first tab, the two bending portions being arranged in a spaced manner along the second direction, the body being located between the two bending portions along the second direction, and the bending portions being located between the body and the shell body along the second direction; the first insulating member having two first portions arranged in a spaced manner along the second direction, the two bending portions being arranged correspondingly with the two first portions, and one end of the bending portion away from the body being connected with the corresponding first portion along the first direction; a projection of the bending portion covering a projection of the first tab on a same projection plane perpendicular to the second direction.

4. The battery cell of any one of claims 1-3, wherein, The second insulating member and the electrode assembly form an accommodating space, two ends of the accommodating space in the third direction forming second openings respectively.

5. The battery cell of claim 3, wherein, The bending portion has a first end and a second end along the third direction, the main body has a third end and a fourth end along the third direction, the first end and the third end being arranged correspondingly, the second end and the fourth end being arranged correspondingly, the first end and the third end having a first gap therebetween, and the second end and the fourth end having a second gap therebetween.

6. The battery cell of claim 3, wherein, The bending portion is provided with a positioning hole, a projection of the positioning hole not overlapping a projection of the first tab and not overlapping a projection of the main body on a same projection plane perpendicular to the second direction.

7. The battery cell of claim 6, wherein, The positioning holes are multiple, and the multiple positioning holes are arranged at intervals along the third direction.

8. The battery cell of claim 3, wherein, The bending part is connected with the body through a transition part, and the transition part is provided with multiple second through holes at intervals along the third direction.

9. The battery cell of claim 8, wherein, Along the third direction, a length of the second through hole is L1, and 0.8mm≤L1≤1.2mm is satisfied; and / or, Along the third direction, a spacing between two adjacent second through holes is L2, and 0.8mm≤L2≤1.2mm is satisfied.

10. The battery cell of claim 1, wherein, The thickness of the second insulating piece is 0.03mm-0.2mm.

11. The battery cell of claim 3, wherein, The end cover assembly comprises a first wall, a third insulating piece and a first electrode terminal, the first electrode terminal is arranged on the first wall, the third insulating piece is connected with the first wall, and the third insulating piece is located between the first wall and the body, and the body is connected with the third insulating piece.

12. The battery cell of claim 11, wherein, The battery monomer further comprises a first adapter, and the first tab is connected with the first electrode terminal through the first adapter. Along the first direction, part of the second insulating piece is arranged between the third insulating piece and the first adapter.

13. The battery cell of claim 1, wherein, The end cover assembly further comprises a pressure relief mechanism, and the second insulating piece has a third through hole for avoiding the pressure relief mechanism.

14. A battery device characterized by comprising: The battery monomer comprises the battery monomer as claimed in any one of claims 1-13.

15. An energy storage device, characterized by, The battery device comprises the battery device as claimed in claim 14.

16. An energy storage system characterized by, The energy storage device comprises the energy storage device as claimed in claim 15, and the energy storage converter is used for electrically connecting the power generation device and the energy storage device.

17. A charging network characterized in that, The charging pile comprises the energy storage device as claimed in claim 15, and the energy storage device is used for providing electric energy for the charging pile.

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