Battery cells, battery devices, power consumption devices and energy storage devices

Abstract

The present application discloses a battery cell, a battery device, an electrical device and an energy storage device. The battery cell of the present application includes an electrode assembly, a shell and a pressure relief mechanism. The shell includes an end cover and a shell, the electrode assembly is located in the shell, the shell is provided with an opening, the end cover is provided on the opening, the end cover includes a first cover body, a second cover body and a support member, the first cover body is provided with a second cover body on the side facing the electrode assembly, the first cover body is connected to the shell, the support member is located on the side of the first cover body facing the second cover body, and is provided in the second cover body, the support member is respectively in contact with the first cover body and the electrode assembly, the support member is a support member with a melting point greater than the melting point of the second cover body, and the first cover body is a cover body with a melting point greater than the melting point of the second cover body. When the battery cell is in thermal runaway, as the temperature rises, the second cover body reaches the melting point first and produces a large deformation. At this time, the support member still effectively supports the electrode assembly, and when the pressure relief mechanism is opened, the probability of the electrode assembly blocking the pressure relief mechanism can be reduced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery device, an electrical device and an energy storage device. Background Art

[0002] When a battery cell thermally runs away, since part of the end cover is a plastic part and the electrode assembly inside the battery cell is supported by the plastic part, when the battery cell thermally runs away, the emissions inside the battery cell are discharged through the explosion-proof valve, and the high temperature inside the battery cell will cause the plastic parts of the battery cell to deform significantly, causing the electrode assembly to easily move toward one side of the end cover under the pressure of the emissions, and the electrode assembly can easily block the explosion-proof valve, making it difficult to discharge emissions when the battery cell thermally runs away. Utility Model Content

[0003] In view of the above problems, the present application provides a battery cell, a battery device, an electrical device and an energy storage device, which can improve the supporting effect of the end cover on the electrode assembly during thermal runaway.

[0004] In a first aspect, the present application provides a battery cell, comprising:

[0005] Electrode assembly;

[0006] The housing comprises an end cap and a shell, the electrode assembly is located in the shell, the shell is provided with an opening, the end cap is covered on the opening, the end cap comprises a first cover body, a second cover body and a support member, the second cover body is provided on the side of the first cover body facing the electrode assembly, the first cover body is connected to the shell, the support member is located on the side of the first cover body facing the second cover body, and is provided in the second cover body, the support member is respectively in contact with the first cover body and the electrode assembly, the support member is a support body with a melting point greater than that of the second cover body, and the first cover body is a cover body with a melting point greater than that of the second cover body;

[0007] The pressure relief mechanism is arranged on the end cover and is used to be actuated when the internal pressure or temperature of the battery cell reaches a predetermined threshold value to discharge the exhaust in the housing.

[0008] When the battery cell thermally runs away, the pressure relief mechanism opens and discharges the emissions during thermal runaway, such as high-temperature and high-pressure gas, to relieve pressure and temperature of the battery cell. The support member is a support member having a melting point greater than that of the second cover body, and the first cover body is a cover body having a melting point greater than that of the second cover body. During the temperature rise due to thermal runaway of the battery cell, the temperature of thermal runaway first approaches or reaches the melting point of the second cover body. Even if the second cover body undergoes a large deformation, the support member still effectively supports the electrode assembly. Since the support member is located on the side of the first cover body facing the second cover body and abuts against the first cover body, the first cover body effectively limits the support member to reduce the probability of the electrode assembly moving toward the end cover. When the pressure relief mechanism is opened, the probability of the electrode assembly blocking the pressure relief mechanism can be reduced, thereby improving the safety of the battery cell.

[0009] In some embodiments, the support member is a support body having a melting point greater than or equal to 600°C; and / or, the first cover body is a cover body having a melting point greater than or equal to 600°C.

[0010] When the battery cell thermally runs away, the probability of the support member and the first cover being melted can be reduced, thereby improving the reliability of the support member supporting the battery cell, so that high-temperature emissions can be discharged in time when the battery cell thermally runs away, thereby improving the safety of the battery cell.

[0011] In some embodiments, a groove is provided on a side of the second cover body facing the first cover body, and the support member is clamped in the groove.

[0012] The support member is clamped in the groove, which can limit the movement of the support member along the height direction of the shell, so that the support member can support the electrode assembly at a predetermined position during installation, thereby improving the installation accuracy of the support member.

[0013] In some embodiments, the support member includes a first support member, the pressure relief mechanism is provided with a first support member on at least one side along the first direction, the groove includes a first groove, the first support member is located in the first groove, the first support member has a gradient section, and the cross-sectional area of ​​the gradient section increases along the direction from the shell to the end cover. The cross-sectional area of ​​the gradient section is perpendicular to the thickness direction of the end cover, the surface of the gradient section facing the first groove abuts against the side wall of the first groove, and the first direction intersects with the height direction of the shell.

[0014] The gradient section of the first support member is clamped in the first groove and can be kept from falling off during plastic demoulding, inversion, transportation and the entire top cover production process after injection molding, so that the first support member can support the electrode assembly at a predetermined position.

[0015] In some embodiments, a first positioning hole is provided on the bottom wall of the first groove, the first positioning hole passes through the bottom wall of the first groove, a first positioning protrusion is provided on the bottom of the first support member, at least part of the first positioning protrusion is located in the first positioning hole, and one end of the first positioning protrusion facing the electrode assembly is flush with the end of the first positioning hole facing the electrode assembly, or the first positioning protrusion protrudes from the end of the first positioning hole facing the electrode assembly, and the first positioning protrusion abuts against the electrode assembly.

[0016] The first positioning hole and the first positioning protrusion cooperate with each other to initially position the first support member during the injection molding process so that it will not be offset under the impact of the injection fluid during the injection molding process, thereby enabling the first support member to support the electrode assembly at a predetermined position to improve the production quality of the end cover; at the same time, the first positioning protrusion supports the electrode assembly, which can reduce the probability of the electrode assembly blocking the pressure relief mechanism during the discharge process to improve the discharge effect.

[0017] In some embodiments, the support member includes a second support member, the groove includes a second groove, the second support member is clamped in the second groove, the second support member is located on the side of the pressure relief mechanism facing the electrode assembly, along the height direction of the shell, the projection of the second support member on the first cover body coincides with at least a partial projection of the pressure relief mechanism, the second support member and the first cover body jointly define a discharge channel, and the discharge channel is used to discharge the discharge in the outer shell when the pressure relief mechanism is actuated.

[0018] The second support member not only supports the electrode assembly, but also enables high-temperature emissions to be discharged to the outside of the battery cell through the emission channel and the pressure relief mechanism when the battery cell thermally runs away, thereby reducing the probability of at least part of the emission channel being blocked, thereby improving the safety of the battery cell.

[0019] In some embodiments, the interior of the end cover has a discharge channel, the discharge channel includes an inlet, an outlet and a cavity, the second support member includes a side wall body and a bottom wall body, the side wall body is connected to the bottom wall body and together encloses the cavity, and the inlet respectively penetrates the side wall body and the side wall of the second groove; or, the inlet respectively penetrates the bottom wall body and the bottom wall of the second groove, or, there are multiple inlets, a part of the inlets respectively penetrate the side wall body and the side wall of the second groove, and another part of the inlets respectively penetrate the bottom wall body and the bottom wall of the second groove, and the outlet is connected to the cavity.

[0020] The setting of the cavity can make the thermal runaway emissions gather in the cavity from the inlet, so that when the thermal runaway pressure relief mechanism is turned on, the thermal runaway emissions are discharged through the cavity and the pressure relief mechanism. Due to the supporting effect of the second support member, the probability of the electrode assembly blocking the pressure relief mechanism can be reduced, so that it can be discharged smoothly, thereby improving the safety of the battery cell.

[0021] In some embodiments, the bottom wall of the second groove is connected to a limiting portion, the limiting portion and the bottom wall of the second groove together define a limiting hole, and the first portion of the second support member is located in the limiting hole.

[0022] Thus, the second support member can be fixed to the bottom wall of the second groove through the limiting portion to reduce the probability of the limiting portion deviating from the predetermined position, so that the second support member can support the electrode assembly at the predetermined position, thereby enabling the first support member to support the electrode assembly at the predetermined position to improve the production quality of the end cover.

[0023] In some embodiments, there are multiple entrances that pass through the bottom wall body and the bottom wall of the second groove, the bottom wall body has a first connecting rib, and the bottom wall of the second groove has a second connecting rib. The first connecting rib and the second connecting rib separate two adjacent entrances. The first connecting rib includes a first part, a second part, and a third part. The first part and the third part are located at both ends of the second part. The first part and the third part are respectively connected to the second part. The first part, the second part, and the third part jointly define a receiving groove. The limiting portion is located in the receiving groove and is connected to the second connecting rib.

[0024] The limiting part is located in the accommodating groove, which can reduce the space occupied by the limiting part in the through hole, make the discharge smoother, and improve the safety of the battery cell.

[0025] In some embodiments, the limiting portion is integrally formed with the bottom wall of the second groove.

[0026] Thus, the limiting portion can be firmly connected to the bottom wall, so as to reduce the probability of the second supporting member deviating from the predetermined position and improve the production quality of the end cover.

[0027] In some embodiments, a second positioning hole is provided on the bottom wall of the second groove, the second positioning hole passes through the bottom wall of the second groove, the bottom of the second support member has a second positioning protrusion, at least part of the second positioning protrusion is located in the second positioning hole, and one end of the second positioning protrusion facing the electrode assembly is flush with the end of the second positioning hole facing the electrode assembly, or, the second positioning protrusion facing one end of the electrode assembly protrudes out of the end of the second positioning hole facing the electrode assembly, and the second positioning protrusion abuts against the electrode assembly.

[0028] The second positioning hole and the second positioning protrusion cooperate with each other to initially position the second support member during the injection molding process so that it will not deviate under the impact of the injection fluid during the injection molding process, thereby enabling the second support member to support the electrode assembly at a predetermined position to improve the production quality of the end cover; at the same time, the second positioning protrusion supports the electrode assembly, thereby reducing the probability of the electrode assembly blocking the pressure relief mechanism during the discharge process and improving the discharge effect.

[0029] In some embodiments, the support member is an insulating member, or the support member includes a main body and an insulating layer, and the outer surface of the main body is provided with the insulating layer.

[0030] Thus, the insulation protection capability of the end cover to the electrode assembly can be improved, thereby improving the safety of the battery cell.

[0031] In some embodiments, the second cover is a plastic piece; and / or the first cover is a metal piece.

[0032] Thus, at least one of the positive electrode terminal and the negative electrode terminal in the battery cell can be insulated from the end cover by the plastic member, so as to improve the safety of the battery cell.

[0033] In a second aspect, the present application provides a battery device, including a battery cell assembly, wherein the battery cell assembly includes a plurality of battery cells according to the first aspect.

[0034] Since the battery device includes all the technical features of the battery cell of the first aspect, the effects are the same as those described above and will not be described in detail here.

[0035] In a third aspect, the present application provides an electrical device, comprising the battery device of the second aspect, and the battery device is used to provide electrical energy to the electrical device.

[0036] Since the electrical device includes all the technical features of the battery device of the second aspect, the effects are the same as those described above and will not be described in detail here.

[0037] In a fourth aspect, the present application provides an energy storage device, including a cabinet and a battery cluster, wherein the battery cluster is accommodated in the cabinet, and the battery cluster includes a plurality of battery devices according to the second aspect.

[0038] Since the energy storage device includes all the technical features of the battery device of the first aspect, the effects are the same as those described above and will not be described in detail here.

[0039] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0041] Figure 1A cross-sectional view of a longitudinal section of a battery cell according to an embodiment of the present application, wherein the longitudinal section passes through a first support member and a second support member of the battery cell;

[0042] Figure 2 for Figure 1 A local enlarged view at location I;

[0043] Figure 3 for Figure 1 A local enlarged view of location II;

[0044] Figure 4 An exploded view of a second cover and a support member in a battery cell according to an embodiment of the present application;

[0045] Figure 5 A partial exploded view of a second cover and a support member in a battery cell according to an embodiment of the present application;

[0046] Figure 6 A front view of a second cover in a battery cell according to an embodiment of the present application;

[0047] Figure 7 for Figure 6 AA section view;

[0048] Figure 8 This is a structural diagram of a first support member in a battery cell according to an embodiment of the present application;

[0049] Fig. 9 for Figure 8 BB cross-sectional view;

[0050] Fig.10 An axonometric diagram of a second support member in a battery cell according to an embodiment of the present application from a first perspective;

[0051] Fig.11 An exploded diagram of a battery device according to an embodiment of the present application;

[0052] Fig.12 A structural diagram of a vehicle in which an electric device according to an embodiment of the present application is used;

[0053] Fig.13 This is an axonometric diagram of an energy storage device according to an embodiment of the present application.

[0054] The reference numerals in the specific implementation manner are as follows:

[0055] 1000. Vehicles;

[0056] 100. Battery device;

[0057] 110, box body; 1101, first box body; 1102, second box body;

[0058] 120, battery cell assembly; 1201, battery cell; 10, housing; 11, end cover; 111, first cover; 112, second cover; 1121, groove; 11211, first groove; 112111, first positioning hole; 11212, second groove; 112121, second positioning hole; 112122, second connecting rib; 112123, limiting portion; 113, support member; 1131, first support Part; 11311, first positioning protrusion; 11312, gradient section; 1132, second support member; 11321, side wall body; 11322, bottom wall body; 113221, second positioning protrusion; 113222, first connecting rib; 113223, receiving groove; 114, discharge channel; 1141, inlet; 1142, outlet; 1143, cavity; 12, shell; 13, electrode assembly; 14, pressure relief mechanism;

[0059] 2000, energy storage device; 2100, cabinet; 2200, battery cluster;

[0060] X, first direction; Z, height direction. DETAILED DESCRIPTION

[0061] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0062] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0063] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0064] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0065] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0066] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0067] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0068] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0069] The electrode assembly inside the battery cell is supported by the end cover. Since a part of the end cover is a plastic part, when the battery cell is in thermal runaway, the plastic part will melt and deform significantly, causing support failure. The electrode assembly will move toward the end cover under the action of internal pressure and easily block the explosion-proof valve of the battery cell, causing the thermal runaway emissions to be unable to be discharged smoothly from the explosion-proof valve, resulting in difficulty in discharge when the battery cell is in thermal runaway.

[0070] In view of this, the present application provides a battery cell. When the battery cell thermally runs away, the pressure relief mechanism opens and discharges the emissions during thermal runaway. The support member is a support member having a melting point greater than that of the second cover body, and the first cover body is a cover body having a melting point greater than that of the second cover body. During the process of thermal runaway heating of the battery cell, the temperature of thermal runaway first approaches or reaches the melting point of the second cover body. Even if the second cover body undergoes a large deformation, the support member still effectively supports the electrode assembly. Since the support member is located on the side of the first cover body facing the second cover body and abuts against the first cover body, the first cover body effectively limits the support member to reduce the probability of the electrode assembly moving toward the end cover. When the pressure relief mechanism is opened, the probability of the electrode assembly blocking the pressure relief mechanism can be reduced, thereby improving the safety of the battery cell.

[0071] The battery cell of the present application may be a secondary battery, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0072] The battery cells of the present application may be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., but the embodiments of the present application are not limited to this.

[0073] The battery cells may be cylindrical battery cells, prismatic battery cells, soft-pack battery cells or battery cells of other shapes. Prismatic battery cells include square-shell battery cells, blade-shaped battery cells, and polygonal prismatic batteries. Polygonal prismatic batteries are, for example, hexagonal prismatic batteries, etc. There is no particular limitation in this application.

[0074] For the convenience of explanation, please refer to the following examples. Figure 1-Figure 10 , a battery cell 1201 in some embodiments of the present application is taken as an example for description.

[0075] The battery cell 1201 includes an electrode assembly 13, a shell 10 and a pressure relief mechanism 14. The shell 10 includes an end cap 11 and a shell 12. The electrode assembly 13 is located in the shell 12. The shell 12 is provided with an opening. The end cap 11 is covered on the opening. The end cap 11 includes a first cover 111, a second cover 112 and a support 113. The second cover 112 is provided on the side of the first cover 111 facing the electrode assembly 13. The first cover 111 is connected to the shell 12. The support 113 is located on the side of the first cover 111 facing the second cover 112 and is provided in the second cover 112. The support 113 is respectively in contact with the first cover 111 and the electrode assembly 13. The support 113 is a support having a melting point greater than that of the second cover 112. The first cover 111 is a cover having a melting point greater than that of the second cover 112. The pressure relief mechanism 14 is disposed on the end cover 11 , and is used to be actuated when the internal pressure or temperature of the battery cell 1201 reaches a predetermined threshold value, so as to discharge the exhaust in the housing 10 .

[0076] The electrode assembly 13 includes a positive electrode, a negative electrode, and a separator, and the separator is arranged between the negative electrode and the positive electrode. During the charge and discharge process of the battery cell 1201, active ions (such as lithium ions) are inserted and removed back and forth 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.

[0077] The electrode assembly 13 may be a wound structure, a laminated structure, or a mixed structure of a wound structure and a laminated structure.

[0078] The pressure relief mechanism 14 performs an action or the weak structure provided in the pressure relief mechanism 14 is destroyed, thereby forming an opening or channel for internal pressure or temperature to be released. The threshold design varies according to different design requirements. The threshold may depend on one or more materials of the positive electrode sheet, negative electrode sheet, electrolyte and separator in the battery cell 1201. The pressure relief mechanism 14 can be integrally formed with the housing 10. As an example, the pressure relief mechanism 14 can also be separately arranged and connected with the housing 10. The "actuation" mentioned in this application means that the pressure relief mechanism 14 produces an action or is activated to a certain state, so that the internal pressure and temperature of the battery cell 1201 can be released. The action generated by the pressure relief mechanism 14 may include but is not limited to: the components in the pressure relief mechanism 14 move to form the discharge channel 114, at least a part of the pressure relief mechanism 14 is broken, broken, torn or opened, etc. When the pressure relief mechanism 14 is actuated, the high-temperature and high-pressure substances inside the battery cell 1201 will be discharged from the actuated part as emissions. In this way, the pressure and temperature of the battery cell 1201 can be released under controllable pressure or temperature, thereby reducing the occurrence of potential more serious accidents.

[0079] The emissions from the battery cell 1201 include, but are not limited to: electrolyte, dissolved or split positive and negative electrodes, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, and the like.

[0080] When the battery cell 1201 thermally runs away, the pressure relief mechanism 14 opens and discharges the emissions during thermal runaway. The support member 113 is a support member with a melting point greater than that of the second cover 112. The first cover 111 is a cover member with a melting point greater than that of the second cover 112. During the temperature rise due to thermal runaway of the battery cell 1201, the temperature of thermal runaway first approaches or reaches the melting point of the second cover 112. Even if the second cover 112 undergoes a large deformation, the support member 113 still effectively supports the electrode assembly 13. Since the support member 113 is located on the side of the first cover 111 facing the second cover 112 and abuts against the first cover 111, the first cover 111 effectively limits the support member 113 to reduce the probability of the electrode assembly 13 moving toward the end cover 11. When the pressure relief mechanism 14 is opened, the probability of the electrode assembly 13 blocking the pressure relief mechanism 14 can be reduced, thereby improving the safety of the battery cell 1201.

[0081] In some embodiments, the electrode assembly 13 includes a positive electrode, a negative electrode, and a separator, and the separator is disposed between the negative electrode and the positive electrode. During the charge and discharge process of the battery cell 1201, active ions (such as lithium ions) are embedded and released back and forth between the positive electrode and the negative electrode. The separator is disposed 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 active ions to pass through.

[0082] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0083] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0084] As an example, the positive electrode current collector may be a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, titanium or silver, etc., may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0085] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also referred to as LFP), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include but are not limited to lithium cobalt oxide (such as LiCoO 2 ), lithium nickel oxide (such as LiNiO 2 ), lithium manganese oxide (such as LiMnO 2 、LiMn 2 O 4 ), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 (Also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O 2 (Also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O 2 (Also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O 2 (Also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O 2 (Also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.8 Co 0.15 Al 0.05 O 2 ) and at least one of its modified compounds. The modified compound refers to a substance obtained by modification means such as doping or coating on the basis of the above substances.

[0086] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a foamed nickel, a foamed copper, a foamed aluminum, a foamed alloy, or a foamed carbon. When the foamed metal is used as the positive electrode, the positive electrode active material may not be disposed on the surface of the foamed metal, but of course, the positive electrode active material may also be disposed. As an example, the positive electrode active material is filled or / and deposited in the foamed metal.

[0087] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0088] As an example, the negative electrode current collector may be a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, titanium or silver, etc., may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0089] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0090] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0091] As an example, the negative electrode active material may adopt the negative electrode active material for battery cell 1201 known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for battery cell 1201 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0092] In some embodiments, the negative electrode may be a foam metal. The foam metal may be foam nickel, foam copper, foam aluminum, foam alloy, or foam carbon, etc. When the foam metal is used as the negative electrode sheet, the surface of the foam metal may not be provided with a negative electrode active material, but of course, a negative electrode active material may also be provided.

[0093] As an example, a negative electrode active material may be filled and / or deposited in the negative electrode current collector.

[0094] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0095] In some embodiments, the electrode assembly 13 further includes a separator, which is disposed between the positive electrode and the negative electrode.

[0096] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical stability and mechanical stability can be selected.

[0097] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without special restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surface of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can also be coated on the surface of the separator.

[0098] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0099] In some embodiments, the battery cell 1201 further includes an electrolyte, which plays a role in conducting ions between the positive and negative electrodes. The present application has no specific restrictions on the type of electrolyte, which can be selected according to needs. The electrolyte can be liquid, gel or solid.

[0100] The liquid electrolyte includes an electrolyte salt and a solvent.

[0101] In some embodiments, the electrolyte salt can be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0102] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent can also be selected from ether solvents. Ether solvents can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0103] In some embodiments, the electrolyte may further optionally include additives. For example, the additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain properties of the battery cell 1201, such as additives that improve the overcharge / fast charge performance of the battery cell 1201, additives that improve the high temperature performance of the battery cell 1201, and additives that improve the low temperature performance of the battery cell 1201.

[0104] Among them, the gel electrolyte includes a polymer as a skeleton network and can be used in combination with an ionic liquid-lithium salt.

[0105] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0106] As examples, the polymer of the polymer solid electrolyte may include polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, a polyionic liquid, cellulose, and the like.

[0107] As an example, the inorganic solid electrolyte can be an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0108] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0109] The electrode assembly 13 may be a wound structure, a laminated structure, or a mixed structure of a wound structure and a laminated structure.

[0110] In some embodiments, the electrode assembly 13 is a wound structure. The positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0111] In some embodiments, the electrode assembly 13 is a laminate structure.

[0112] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0113] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0114] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0115] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0116] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0117] In some embodiments, the shape of the electrode assembly 13 can be cylindrical, flat, or polygonal.

[0118] In some embodiments, the electrode assembly 13 is provided with tabs, which can lead current out of the electrode assembly 13. The tabs include a positive tab and a negative tab.

[0119] In some embodiments, when the housing 10 is a non-sealed structure, the pressure relief mechanism 14 can be configured as a pressure relief hole, and the pressure relief hole is used to discharge the exhaust inside the battery cell 1201 .

[0120] In some embodiments, at least one electrode terminal is disposed on the housing 10, and the electrode terminal is electrically connected to the electrode tab. The electrode terminal can be directly connected to the electrode tab, or indirectly connected to the electrode tab through a current collecting member. The electrode terminal can be disposed on the end cap 11, or on the housing 12.

[0121] In some embodiments, please refer to Figure 1-Figure 4 , the support member 113 is a support body having a melting point greater than or equal to 600°C; and / or, the first cover body 111 is a cover body having a melting point greater than or equal to 600°C.

[0122] The first cover 111 may be made of metal, including metal element or alloy, such as steel, aluminum or aluminum alloy.

[0123] The material of the support member 113 may be the same as or different from that of the first cover 111. The material of the support member 113 may be metal or non-metal. For example, the material of the support member 113 includes high temperature resistant materials such as metal, alloy or ceramic.

[0124] When the battery cell 1201 thermally runs away, the probability of the support member 113 and the first cover body 111 being melted can be reduced, thereby improving the reliability of the support member 113 supporting the battery cell 1201, so that the high-temperature emissions can be discharged in time when the battery cell 1201 thermally runs away, thereby improving the safety of the battery cell 1201.

[0125] In some embodiments, please refer to Figure 1-Figure 4 A groove 1121 is formed on a side of the second cover body 112 facing the first cover body 111 , and the support member 113 is clamped in the groove 1121 .

[0126] The support member 113 is clamped in the groove 1121 , and may be clamped in the groove 1121 by injection molding, or a buckle may be provided on the side wall of the groove 1121 to fix the support member 113 by the buckle.

[0127] The shape of the groove 1121 is not specifically limited and can be reasonably designed according to actual needs.

[0128] The support member 113 is clamped in the groove 1121 , which can limit the movement of the support member 113 along the height direction Z of the shell 12 , so that the support member 113 can support the electrode assembly 13 at a predetermined position during installation, thereby improving the installation accuracy of the support member 113 .

[0129] In some embodiments, please refer to Figure 1-Figure 9 The support member 113 includes a first support member 1131. The pressure relief mechanism 14 is provided with a first support member 1131 on at least one side along the first direction X. The groove 1121 includes a first groove 11211. The first support member 1131 is located in the first groove 11211. The first support member 1131 has a gradient section 11312. Along the direction from the shell 12 to the end cover 11, the area of ​​the cross section of the gradient section 11312 increases gradually. The cross section of the gradient section 11312 is perpendicular to the thickness direction of the end cover 11. The surface of the gradient section 11312 facing the first groove 11211 abuts against the side wall of the first groove 11211. The first direction X intersects with the height direction Z of the shell 12.

[0130] The number of the first support members 1131 on the same side of the pressure relief mechanism 14 along the first direction X may be one or more, and the structures of the multiple first support members 1131 may be the same, partially the same, or different.

[0131] The structure of the first support member 1131 can be designed according to actual needs. For example, the first support member 1131 can be a combination of a cone and a cylinder, and the cylinder and the cone bottom are connected, which can be specifically bonded, welded or integrally formed. The cone can be a cone, a polygonal cone or other special-shaped cones. The cylinder can be a cylinder, a polygonal cylinder, an elliptical cylinder or other special-shaped cylinders. The cone can be used as a gradient section 11312. The cone can be a structure formed by combining one end or multiple sections of cones with different tapers. The first support member 1131 can also be a special-shaped structure with a gradient section 11312.

[0132] The height direction Z of the housing 12 refers to the direction between the housing 12 and the end cover 11 .

[0133] The gradient section 11312 of the first support member 1131 is clamped in the first groove 11211 and does not fall off during plastic demoulding, inversion, transportation and the entire top cover production process after injection molding, so that the first support member 1131 can support the electrode assembly 13 at a predetermined position.

[0134] In some embodiments, please refer to Figure 2 A first positioning hole 112111 is provided on the bottom wall of the first groove 11211, and the first positioning hole 112111 passes through the bottom wall of the first groove 11211. A first positioning protrusion 11311 is provided on the bottom of the first support member 1131, and at least part of the first positioning protrusion 11311 is located in the positioning hole. The first positioning protrusion 11311 is flush with one end of the first positioning hole 112111 facing the electrode assembly 13, or the first positioning protrusion 11311 protrudes from one end of the first positioning hole 112111 facing the electrode assembly 13, and the first positioning protrusion 11311 abuts against the electrode assembly 13.

[0135] The contour shape of the first positioning hole 112111 can be, but is not limited to, circular, polygonal, elliptical or other special shapes.

[0136] The profile shape of the cross section of the first positioning protrusion 11311 may be the same as or different from the profile shape of the first positioning hole 112111. The first positioning protrusion 11311 may be a hemispherical protrusion, a cylindrical protrusion, or a conical protrusion, etc. The cylindrical protrusion may be a cylindrical protrusion or a multi-prism protrusion, and the conical protrusion may be a conical protrusion or a pyramidal protrusion, etc.

[0137] The first positioning hole 112111 and the first positioning protrusion 11311 cooperate with each other to initially position the first support member 1131 during the injection molding process, so that it will not be offset under the impact of the injection fluid during the injection molding process, thereby enabling the first support member 1131 to support the electrode assembly 13 at a predetermined position to improve the production quality of the end cover 11; at the same time, the first positioning protrusion 11311 supports the electrode assembly 13, which can reduce the probability of the electrode assembly 13 blocking the pressure relief mechanism 14 during the discharge process, thereby improving the discharge effect.

[0138] In some embodiments, the support member 113 includes a second support member 1132, the groove 1121 includes a second groove 11212, the second support member 1132 is clamped in the second groove 11212, the second support member 1132 is located on the side of the pressure relief mechanism 14 facing the electrode assembly 13, along the height direction Z of the shell 12, the projection of the second support member 1132 on the first cover body 111 coincides with at least a portion of the projection of the pressure relief mechanism 14, the second support member 1132 and the first cover body 111 jointly define a discharge channel 114, and the discharge channel 114 is used to discharge the exhaust in the outer shell 10 when the pressure relief mechanism 14 is actuated.

[0139] The second support member 1132 can be clamped in the second groove 11212 by injection molding, or a buckle can be provided on the second cover body 112 to fix the second support member 1132 by the buckle.

[0140] As an example, the second support member 1132 can be a cover structure, and the second support member 1132 covers the pressure relief mechanism 14, and the cavity 1143 in the second support member 1132 is connected to the space in the shell 12. When the pressure relief mechanism 14 is actuated, the emissions in the shell 12 can be discharged to the outside of the shell 12 through the cavity 1143 in the second support member 1132 to relieve pressure and temperature of the battery cell 1201.

[0141] The second support member 1132 not only supports the electrode assembly 13, but also, when the battery cell 1201 is in thermal runaway, high-temperature emissions can be discharged to the outside of the battery cell 1201 through the emission channel 114 and the pressure relief mechanism 14, so as to reduce the probability of at least part of the emission channel 114 being blocked, thereby improving the safety of the battery cell 1201.

[0142] In some embodiments, please refer to Figure 3The end cover 11 has a discharge channel 114 inside, and the discharge channel 114 includes an inlet 1141, an outlet 1142 and a cavity 1143. The second support member 1132 includes a side wall body 11321 and a bottom wall body 11322. The side wall body 11321 is connected to the bottom wall body 11322 and together encloses the cavity 1143. The inlet 1141 penetrates the side wall of the side wall body 11321 and the side wall of the second groove 11212 respectively, or the inlet 1141 penetrates the bottom wall body 11322 and the bottom wall of the second groove 11212 respectively, or the number of the inlet 1141 is multiple, a part of the inlet 1141 penetrates the side wall of the side wall body 11321 and the second groove 11212 respectively, and another part of the inlet 1141 penetrates the bottom wall body 11322 and the bottom wall of the second groove 11212 respectively, and the outlet 1142 is connected to the cavity 1143.

[0143] When there are multiple inlets 1141, a part of the inlets 1141 can pass through the side wall 11321 and the side wall of the second groove 11212, or all of the inlets 1141 can pass through the side wall 11321 and the side wall of the second groove 11212 to achieve communication between the inlet 1141 and the cavity 1143; alternatively, a part of the inlets 1141 can pass through the side wall 11321 and the side wall of the second groove 11212, and another part of the inlets 1141 pass through the bottom wall 11322 and the bottom wall of the second groove 11212 to achieve communication between the inlet 1141 and the cavity 1143; alternatively, all of the inlets 1141 pass through the bottom wall 11322 and the bottom wall of the second groove 11212.

[0144] The setting of cavity 1143 can make the thermal runaway emissions gather in cavity 1143 from inlet 1141, so that when the thermal runaway pressure relief mechanism 14 is turned on, the thermal runaway emissions can be discharged through cavity 1143 and pressure relief mechanism 14. Due to the supporting effect of the second support member 1132, the probability of the electrode assembly 13 blocking the pressure relief mechanism 14 can be reduced, so that it can be discharged smoothly, thereby improving the safety of the battery cell 1201.

[0145] In some embodiments, please refer to Figure 5 The bottom wall of the second groove 11212 is connected to the limiting portion 112123, and the limiting portion 112123 and the bottom wall of the second groove 11212 jointly define a limiting hole, and the first part of the second support member 1132 is located in the limiting hole.

[0146] The limiting portion 112123 can be a frame structure with multiple frames and notches, and one side of the frame with the notch is connected to the bottom wall of the second groove 11212. The limiting portion 112123 can also be a semi-ring structure, that is, the contour shape of the limiting hole can be an irregular hole or a regular geometric hole, such as a square hole or a triangular hole. It can be reasonably designed according to actual needs and is not specifically limited here.

[0147] The limiting portion 112123 and the bottom wall of the second groove 11212 can be integrally formed by injection molding, or fixed by bonding or welding.

[0148] Thus, the second support member 1132 can be fixed to the bottom wall of the second groove 11212 by the limiting portion 112123 to reduce the probability of the limiting portion 112123 deviating from the predetermined position, so that the second support member 1132 can support the electrode assembly 13 at the predetermined position, thereby enabling the first support member 1131 to support the electrode assembly 13 at the predetermined position, thereby improving the production quality of the end cover 11.

[0149] In some embodiments, please refer to Figure 5 There are multiple entrances 1141 that pass through the bottom wall body 11322 and the bottom wall of the second groove 11212. The bottom wall body 11322 has a first connecting rib 113222, and the bottom wall of the second groove 11212 has a second connecting rib 112122. The first connecting rib 113222 and the second connecting rib 112122 separate two adjacent entrances 1141. The first connecting rib 113222 includes a first part, a second part and a third part. The first part and the third part are located at both ends of the second part. The first part and the third part are respectively connected to the second part. The first part, the second part and the third part jointly define a receiving groove 113223. The limiting portion 112123 is located in the receiving groove 113223 and is connected to the second connecting rib 112122.

[0150] The first part, the second part and the third part can be integrally formed by injection molding, or connected by hot-melt welding or bonding.

[0151] The limiting portion 112123 is located in the accommodating groove 113223 , which can reduce the space occupied by the limiting portion 112123 in the through hole, making the discharge smoother and improving the safety of the battery cell 1201 .

[0152] In some embodiments, the limiting portion 112123 is integrally formed with the bottom wall of the second groove 11212 .

[0153] Thus, the limiting portion 112123 can be firmly connected to the bottom wall to reduce the probability of the second supporting member 1132 deviating from the predetermined position, thereby improving the production quality of the end cover 11.

[0154] In some embodiments, please refer to Figure 3 , Figure 5 and Fig.10 The bottom wall of the second groove 11212 is provided with a second positioning hole 112121, and the second positioning hole 112121 passes through the bottom wall of the second groove 11212. The bottom of the second support member 1132 has a second positioning protrusion 113221, and at least part of the second positioning protrusion 113221 is located in the second positioning hole 112121, and the second positioning protrusion 113221 is arranged flush with the end of the second positioning hole 112121 toward the electrode assembly 13, or, the second positioning protrusion 113221 toward the end of the electrode assembly 13 protrudes from the end of the second positioning hole 112121 toward the electrode assembly 13, and the second positioning protrusion 113221 abuts against the electrode assembly 13.

[0155] The contour shape of the second positioning hole 112121 can be, but is not limited to, circular, polygonal, elliptical or other special shapes.

[0156] The profile shape of the cross section of the second positioning protrusion 113221 may be the same as or different from the profile shape of the second positioning hole 112121. The second positioning protrusion 113221 may be a hemispherical protrusion, a cylindrical protrusion, or a conical protrusion, etc. The cylindrical protrusion may be a cylindrical protrusion or a multi-prism protrusion, and the conical protrusion may be a conical protrusion or a pyramidal protrusion, etc.

[0157] The second positioning hole 112121 and the second positioning protrusion 113221 cooperate with each other to initially position the second support member 1132 during the injection molding process, so that it will not be offset under the impact of the injection fluid during the injection molding process, so that the second support member 1132 can support the electrode assembly 13 at a predetermined position to improve the production quality of the end cover 11; at the same time, the second positioning protrusion 113221 supports the electrode assembly 13, thereby reducing the probability of the electrode assembly 13 blocking the pressure relief mechanism 14 during the discharge process, thereby improving the discharge effect.

[0158] In some embodiments, the support member 113 is an insulating member, or the support member 113 includes a main body and an insulating layer, and the outer surface of the main body is provided with the insulating layer.

[0159] The insulating member includes, but is not limited to, an insulating ceramic member, a silicon nitride member, a silicon carbide member, a mica member or a quartz member.

[0160] The main body may be a metal part or a non-metal part. For example, the main body is a metal part, and the insulating layer includes but is not limited to a boron nitride coating, an aluminum oxide coating, or a ceramic coating.

[0161] Thus, the insulation protection capability of the end cover 11 to the electrode assembly 13 can be improved, so as to improve the safety of the battery cell 1201 .

[0162] In some embodiments, the second cover 112 is a plastic member, and / or the first cover 111 is a metal member.

[0163] The second cover 112 is a plastic part, and at least one of the positive electrode terminal and the negative electrode terminal in the battery cell 1201 can be insulated from the end cover 11 by the plastic part to improve the safety of the battery cell 1201. The first cover 111 is a metal part, which can make the first cover 111 resistant to high temperatures and have a certain strength to limit the support member 113, so that the support member 113 can provide effective support for the electrode assembly 13 when the battery cell 1201 is in thermal runaway.

[0164] For the convenience of explanation, please refer to the following examples. Fig.11 , a battery device 100 according to some embodiments of the present application is taken as an example for description.

[0165] The present application provides a battery device 100 , including a battery cell assembly 120 , wherein the battery cell assembly 120 includes a plurality of battery cells 1201 according to the above-mentioned embodiments.

[0166] The number of the battery cell assembly 120 may be one or more. The battery cell assembly 120 is used to provide voltage and capacity.

[0167] The plurality of battery cells 1201 are connected in series, in parallel or in series-parallel connection via a busbar.

[0168] In some embodiments, the battery cell assembly 120 (Battery Cell Assembly) is generally formed by arranging a plurality of battery cells 1201 .

[0169] As an example, the battery cell assembly 120 may be a battery module (Battery Module), and the battery module is formed by arranging and fixing a plurality of battery cells 1201 to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells 1201 by a cable tie.

[0170] In some embodiments, the battery device 100 may be a battery pack, which includes a case 110 and one or more battery cell assemblies 120 , wherein the battery cell assemblies 120 are accommodated in the case 110 .

[0171] As an example, the battery cell assembly 120 may be a battery module, and the battery cell assembly 120 may be accommodated in the case 110 by fixing the battery module in the case 110 .

[0172] As an example, the battery cell assembly 120 may also be accommodated in the case 110 by directly fixing the plurality of battery cells 1201 to the case 110 .

[0173] As an example, the box 110 may include a first box 1101 and a second box 1102. The first box 1101 and the second box 1102 are buckled together to form a closed space inside the box 110 to accommodate the battery cell assembly 120. The closed space here means covered or closed, which may be sealed or unsealed. The first box 1101 may be a top cover or a bottom plate.

[0174] As an example, the box body 110 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body 110 to accommodate the battery cell assembly 120.

[0175] Since the battery device 100 includes all the technical features of the battery cell 1201 of the above embodiment, the effects are the same as those described above and will not be described in detail herein.

[0176] For the convenience of description, the following embodiments are described by taking an electrical device of some embodiments of the present application as an example.

[0177] The electric device includes the battery device 100 of the above embodiment, and the battery device 100 is used to provide electric energy to the electric device.

[0178] The technical solutions described in the embodiments of the present application are applicable to various electrical devices using battery cells 1201, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, vehicles 1000, ships and spacecraft, for example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0179] Please refer to Fig.12 Taking the electric device as a vehicle 1000 as an example, the box 110 can be used as a part of the chassis structure of the vehicle 1000. For example, part of the box 110 can become at least a part of the floor of the vehicle 1000, or part of the box 110 can become at least a part of the cross beam and longitudinal beam of the vehicle 1000.

[0180] Since the electrical device includes all the technical features of the battery device 100 of the above embodiment, the effects are the same as those described above and will not be described in detail herein.

[0181] For the convenience of explanation, please refer to the following examples. Fig.13 , an energy storage device 2000 of some embodiments of the present application is taken as an example for description.

[0182] The energy storage device 2000 includes a cabinet 2100 and a battery cluster 2200 . The battery cluster 2200 is accommodated in the cabinet 2100 . The battery cluster 2200 includes a plurality of battery devices 100 according to the above embodiments.

[0183] The battery cluster 2200 can improve the voltage and capacity of the energy storage device 2000. The battery cluster 2200 may include a plurality of battery devices 100. The plurality of battery devices 100 are connected in series through a busbar to improve the voltage of the energy storage device 2000. When the energy storage device 2000 includes a plurality of battery clusters 2200, the plurality of battery clusters 2200 are connected in parallel to improve the capacity of the energy storage device 2000.

[0184] The energy storage device 2000 can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems or temporary power supply systems. The energy storage device 2000 can store electrical energy as needed and output electrical energy at an appropriate time. For example, the energy storage device 2000 can store electrical energy during low power consumption and provide electrical energy to relevant users or electrical equipment during peak power consumption. The energy storage system provided in the embodiment of the present application can be any power system that requires the use of the energy storage device 2000.

[0185] In some embodiments, the energy storage device 2000 is an energy storage container or an energy storage cabinet.

[0186] Since the energy storage device 2000 includes all the technical features of the battery device 100 of the above embodiment, the effects are the same as above and will not be described in detail here.

[0187] In an optional embodiment of the battery cell 1201, the battery cell 1201 includes an electrode assembly 13, a shell 10 and a pressure relief mechanism 14. The shell 10 includes an end cap 11 and a shell 12, the electrode assembly 13 is located in the shell 12, the shell 12 is provided with an opening, the end cap 11 is covered on the opening, the end cap 11 includes a first cover 111, a second cover 112 and a support 113, the second cover 112 is provided on the side of the first cover 111 facing the electrode assembly 13, the first cover 111 is connected to the shell 12, the support 113 is located on the side of the first cover 111 facing the second cover 112, and is provided in the second cover 112, the support 113 is respectively in contact with the first cover 111 and the electrode assembly 13, the support 113 is a support having a melting point greater than that of the second cover 112, and the first cover 111 is a cover having a melting point greater than that of the second cover 112. The pressure relief mechanism 14 is provided on the end cover 11, and is used to be actuated when the internal pressure or temperature of the battery cell 1201 reaches a predetermined threshold value to discharge the discharge in the housing 10. The support member 113 is a support body with a melting point greater than or equal to 600°C; and / or the first cover body 111 is a cover body with a melting point greater than or equal to 600°C. A groove 1121 is provided on one side of the second cover body 112 facing the first cover body 111, and the support member 113 is clamped in the groove 1121. The support member 113 includes a first support member 1131. The pressure relief mechanism 14 is provided with a first support member 1131 on at least one side along the first direction X. The groove 1121 includes a first groove 11211. The first support member 1131 is located in the first groove 11211. The first support member 1131 has a gradient section 11312. Along the direction from the shell 12 to the end cover 11, the area of ​​the cross section of the gradient section 11312 increases progressively. The cross section of the gradient section 11312 is perpendicular to the thickness direction of the end cover 11. The surface of the gradient section 11312 facing the first groove 11211 abuts against the side wall of the first groove 11211. The first direction X intersects with the height direction Z of the shell 12. The bottom wall of the first groove 11211 is provided with a first positioning hole 112111, and the first positioning hole 112111 passes through the bottom wall of the first groove 11211. The bottom of the first support member 1131 is provided with a first positioning protrusion 11311, and the first positioning protrusion 11311 is located in the positioning hole, and the first positioning protrusion 11311 abuts against the electrode assembly 13. One end of the first positioning protrusion 11311 facing the electrode assembly 13 is flush with one end of the first positioning hole 112111 facing the electrode assembly 13.The support member 113 also includes a second support member 1132, the groove 1121 includes a second groove 11212, the second support member 1132 is clamped in the second groove 11212, the second support member 1132 is located on the side of the pressure relief mechanism 14 facing the electrode assembly 13, along the height direction Z of the shell 12, the projection of the second support member 1132 on the first cover body 111 coincides with at least a portion of the projection of the pressure relief mechanism 14, the second support member 1132 and the first cover body 111 jointly define a discharge channel 114, and the discharge channel 114 is used to discharge the discharge in the outer shell 10 when the pressure relief mechanism 14 is actuated. The end cover 11 has a discharge channel 114 inside, and the discharge channel 114 includes an inlet 1141, an outlet 1142 and a cavity 1143. The second support member 1132 includes a side wall 11321 and a bottom wall 11322. The side wall 11321 is connected to the bottom wall 11322 and together encloses the cavity 1143. There are multiple inlets 1141, a part of the inlets 1141 penetrates the side wall 11321 and the side wall of the second groove 11212, and another part of the inlets 1141 penetrates the bottom wall 11322 and the bottom wall of the second groove 11212, and the outlet 1142 is connected to the cavity 1143. The bottom wall of the second groove 11212 is connected to the limiting portion 112123, and the limiting portion 112123 and the bottom wall of the second groove 11212 together define a limiting hole, and the first part of the second support member 1132 is located in the limiting hole. There are multiple inlets 1141 that pass through the bottom wall 11322 and the bottom wall of the second groove 11212. The bottom wall 11322 has a first connecting rib 113222, and the bottom wall of the second groove 11212 has a second connecting rib 112122. The first connecting rib 113222 and the second connecting rib 112122 separate two adjacent inlets 1141. The first connecting rib 113222 includes a first portion, a second portion, and a third portion. The first portion and the third portion are located at both ends of the second portion. The first portion and the third portion are connected to the second portion respectively. The first portion, the second portion, and the third portion jointly define a receiving groove 113223. The limiting portion 112123 is located in the receiving groove 113223 and is connected to the second connecting rib 112122. The limiting portion 112123 is integrally formed with the bottom wall of the second groove 11212. The bottom wall of the second groove 11212 is provided with a second positioning hole 112121, and the second positioning hole 112121 passes through the bottom wall of the second groove 11212. The bottom of the second support member 1132 has a second positioning protrusion 113221, and the second positioning protrusion 113221 is located in the second positioning hole 112121, and the second positioning protrusion 113221 abuts against the electrode assembly 13. One end of the second positioning protrusion 113221 facing the electrode assembly 13 is flush with one end of the second positioning hole 112121 facing the electrode assembly 13. The second cover 112 is a plastic part.

[0188] The support member 113 is clamped in the groove 1121, and the support member 113 is made of a high temperature resistant material with a melting point greater than that of the second cover 112, so that when the battery cell 1201 is in thermal runaway, even if the second cover 112 reaches the melting point and deforms, the support member 113 can effectively support the electrode assembly 13, so as to reduce the probability of the electrode assembly 13 moving toward the end cover 11, and when the pressure relief mechanism 14 is opened, it can reduce the probability of the electrode assembly 13 blocking the pressure relief mechanism 14, thereby improving the safety of the battery cell 1201. And the number of the inlet 1141 is multiple, so that the discharge at different positions in the shell 12 can be collected from different directions into the cavity 1143, and the pressure is relieved through the pressure relief mechanism 14, so as to reduce the possibility of the temperature of the battery cell 1201 continuing to rise during thermal runaway, and improve the safety of the battery cell 1201.

[0189] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: Electrode assembly; A housing, comprising an end cap and a shell, wherein the electrode assembly is located in the shell, the shell is provided with an opening, the end cap is covered on the opening, the end cap comprises a first cover, a second cover and a support, the first cover is provided with the second cover on a side of the first cover facing the electrode assembly, the first cover is connected to the shell, the support is located on a side of the first cover facing the second cover and is provided in the second cover, the support is respectively in contact with the first cover and the electrode assembly, the support is a support having a melting point greater than that of the second cover, and the first cover is a cover having a melting point greater than that of the second cover; A pressure relief mechanism is provided on the end cover, and is used to be actuated when the internal pressure or temperature of the battery cell reaches a predetermined threshold value to discharge the exhaust in the housing.

2. The battery cell according to claim 1, characterized in that: The support member is a support body having a melting point greater than or equal to 600°C; and / or the first cover body is a cover body having a melting point greater than or equal to 600°C.

3. The battery cell according to claim 1, characterized in that: A groove is formed on a side of the second cover body facing the first cover body, and the support member is clamped in the groove.

4. The battery cell according to claim 3, characterized in that: The support member includes a first support member, and the first support member is provided on at least one side of the pressure relief mechanism along the first direction, and the groove includes a first groove, and the first support member is located in the first groove. The first support member has a gradient section, and the area of ​​the cross section of the gradient section increases along the direction from the shell to the end cover, and the cross section of the gradient section is perpendicular to the thickness direction of the end cover, and the surface of the gradient section facing the first groove abuts against the side wall of the first groove, and the first direction intersects with the height direction of the shell.

5. The battery cell according to claim 4, characterized in that: A first positioning hole is provided on the bottom wall of the first groove, and the first positioning hole passes through the bottom wall of the first groove. A first positioning protrusion is provided on the bottom of the first support member, and at least part of the first positioning protrusion is located in the first positioning hole. One end of the first positioning protrusion facing the electrode assembly is flush with the end of the first positioning hole facing the electrode assembly, or the first positioning protrusion protrudes from the end of the first positioning hole facing the electrode assembly, and the first positioning protrusion abuts against the electrode assembly.

6. The battery cell according to any one of claims 3 to 5, characterized in that: The support member includes a second support member, and the groove includes a second groove. The second support member is clamped in the second groove. The second support member is located on the side of the pressure relief mechanism facing the electrode assembly. Along the height direction of the shell, the projection of the second support member on the first cover body coincides with at least a partial projection of the pressure relief mechanism. The second support member and the first cover body jointly define a discharge channel, and the discharge channel is used to discharge the discharge in the shell when the pressure relief mechanism is actuated.

7. The battery cell according to claim 6, characterized in that: The end cover has the discharge channel inside, and the discharge channel includes an inlet, an outlet and a cavity. The second support member includes a side wall body and a bottom wall body, and the side wall body is connected to the bottom wall body and together encloses the cavity; the inlet passes through the side wall body and the side wall of the second groove respectively, or the inlet passes through the bottom wall body and the bottom wall of the second groove respectively, or the number of the inlets is multiple, a part of the inlets passes through the side wall body and the side wall of the second groove respectively, and another part of the inlets passes through the bottom wall body and the bottom wall of the second groove respectively, and the outlet is connected to the cavity.

8. The battery cell according to claim 7, characterized in that: The bottom wall of the second groove is connected to a limiting portion, and the limiting portion and the bottom wall of the second groove together define a limiting hole, and the first portion of the second support member is located in the limiting hole.

9. The battery cell according to claim 8, characterized in that: There are multiple entrances that pass through the bottom wall body and the bottom wall of the second groove. The bottom wall body has a first connecting rib, and the second groove has a second connecting rib. The first connecting rib and the second connecting rib separate two adjacent entrances. The first connecting rib includes the first part, the second part and the third part. The first part and the third part are located at both ends of the second part. The first part and the third part are respectively connected to the second part. The first part, the second part and the third part jointly define a receiving groove. The limiting portion is located in the receiving groove and connected to the second connecting rib.

10. The battery cell according to claim 8, characterized in that: The limiting portion is integrally formed with the bottom wall of the second groove.

11. The battery cell according to claim 6, characterized in that: A second positioning hole is provided on the bottom wall of the second groove, and the second positioning hole passes through the bottom wall of the second groove. The bottom of the second support member has a second positioning protrusion, and at least part of the second positioning protrusion is located in the second positioning hole. The second positioning protrusion is arranged flush with one end of the electrode assembly facing the electrode assembly and the second positioning hole is arranged toward the electrode assembly; or, the second positioning protrusion is protruded from one end of the electrode assembly facing the electrode assembly through the second positioning hole, and the second positioning protrusion is in contact with the electrode assembly.

12. The battery cell according to any one of claims 1 to 5, characterized in that: The support member is an insulating member, or the support member includes a main body and an insulating layer, and the insulating layer is provided on the outer surface of the main body.

13. The battery cell according to any one of claims 1 to 5, characterized in that: The second cover body is a plastic part; and / or the first cover body is a metal part.

14. A battery device, characterized in that: It comprises a battery cell assembly, wherein the battery cell assembly comprises a plurality of battery cells according to any one of claims 1 to 13.

15. An electrical device, characterized in that: The battery device comprises the battery device as claimed in claim 14, wherein the battery device is used to provide electrical energy to the electrical device.

16. An energy storage device, characterized in that: The invention comprises a cabinet and a battery cluster, wherein the battery cluster is accommodated in the cabinet and comprises a plurality of battery devices according to claim 14.

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