Battery monomer, battery and electric equipment

Abstract

The utility model discloses a single battery, a battery and electric equipment. The single battery comprises a shell, a shielding piece and a pressing piece, the shell is provided with a first wall which is provided with a weak part; the shielding piece is arranged in the shell and shields at least part of the weak part in the thickness direction of the first wall; the abutting piece is located on the side, away from the first wall, of the shielding piece and abuts against the shielding piece. And the weak part can be opened when the pressure in the shell reaches a certain value, so that the pressure in the shell is reduced, and the probability of structural damage of the battery monomer is reduced. The shielding piece can reduce the impact of the electrolyte on at least part of the weak part in the thickness direction of the first wall, so that the probability that the weak part is opened in advance due to the impact of the electrolyte is reduced to a certain extent. The abutting piece can apply a certain force to the shielding piece, so that the position of the shielding piece is limited, the probability that the shielding piece dissociates to other positions along with flowing of the electrolyte is reduced, and the shielding piece can continuously cover the weak part.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery monomer, a battery and an electrical device. Background Art

[0002] The bottom of the battery cell is provided with a weak part, such as an explosion-proof valve. The electrolyte in the battery cell may be in contact with the explosion-proof valve for a long time, and the flow of the electrolyte will have a certain impact on the explosion-proof valve, causing the explosion-proof valve to open prematurely. In order to reduce the impact of the electrolyte on the explosion-proof valve, in the related art, a shielding member covering the explosion-proof valve is provided in the battery cell. However, the shielding member is easily freed to other positions with the flow of the electrolyte, and thus cannot continuously cover the explosion-proof valve. Utility Model Content

[0003] The utility model provides a battery cell, a battery and an electric device, wherein a shielding piece is easily released to other positions along with the flow of electrolyte, and thus cannot continuously cover a weak part.

[0004] The battery cell of the embodiment of the utility model comprises:

[0005] A housing, the housing having a first wall, the first wall being provided with a weak portion;

[0006] a shielding member, the shielding member being disposed in the housing and covering at least a portion of the weak portion along a thickness direction of the first wall; and

[0007] A pressing member is located at a side of the shielding member away from the first wall, and presses the shielding member.

[0008] In the battery cell of the embodiment of the utility model, the weak part can be opened when the pressure in the shell reaches a certain value to reduce the pressure in the shell, thereby reducing the probability of structural damage to the battery cell. The shielding member can reduce the impact of the electrolyte on at least part of the weak part in the thickness direction of the first wall, thereby reducing the probability of the weak part opening prematurely due to the impact of the electrolyte to a certain extent. The pressure member can apply a certain force to the shielding member, thereby limiting the position of the shielding member, reducing the probability of the shielding member being free to other positions with the flow of the electrolyte, so that the shielding member can continuously cover the weak part.

[0009] In some embodiments, the first wall has a first groove and a second groove, the first groove extends from the outer surface of the first wall to the inner surface of the first wall along the thickness direction of the first wall, the second groove passes through the bottom surface of the first groove and the inner surface of the first wall, and the weak portion is arranged in the first groove.

[0010] In this way, the arrangement of the first groove and the second groove is conducive to thinning the first wall. The weak portion is arranged in the first groove, so that the weak portion can be opened in time when the pressure in the shell reaches a certain value, thereby improving the functional stability of the weak portion.

[0011] In some embodiments, the pressing member includes a plate body and a protrusion disposed on the plate body, the protrusion presses the shielding member, and the protrusion is used to form a fluid channel.

[0012] In this way, the protrusion can press the shielding member to reduce the probability of the shielding member moving to other positions with the flow of electrolyte, so that the shielding member can continuously cover the weak part. The fluid channel can allow part of the electrolyte to flow between the shielding member and the pressing member. When the pressure in the housing reaches a certain value, the electrolyte can impact the shielding member and further impact the weak part, so that the weak part can be opened.

[0013] In some embodiments, there are multiple protrusions, the multiple protrusions are arranged along the width direction of the pressing member, at least one protrusion presses the shielding member, and the fluid channel is formed between the multiple protrusions.

[0014] In this way, the plurality of protrusions can increase the contact area between the pressing member and the shielding member, so that the pressing member can effectively press the shielding member. The fluid channel formed between the plurality of protrusions can make part of the electrolyte flow along a predetermined flow path, so that the flow behavior of the electrolyte can be more accurately controlled. When the pressure in the housing reaches a certain value, the electrolyte impacts the shielding member along the predetermined flow path, and further impacts the weak portion, so that the weak portion can be opened.

[0015] In some embodiments, the plurality of protrusions press against the shielding member, and the area where each protrusion presses against the shielding member is equal.

[0016] In this way, the area of ​​each protrusion pressing against the shielding member is equal, which ensures that the pressure on the shielding member is evenly distributed and does not cause uneven pressure due to a protrusion being too large or too small. This helps to improve the stability of the shielding member and helps to evenly distribute the electrolyte around the weak part.

[0017] In some embodiments, the width of the weak portion is W1, and along the width direction of the pressing member, the farthest distance between the plurality of protrusions is W2, and W1 and W2 satisfy: W2≥W1+4, in mm.

[0018] In this way, the area where the protrusion presses the shielding member can be distributed outside the weak portion, so that the shielding member can be effectively pressed.

[0019] In some embodiments, along the width direction of the pressing member, the farthest distance between the plurality of protrusions is W2, the width of the shielding member is W3, and W2 and W3 satisfy: 0≤|W3-W2|≤10, in mm.

[0020] In this way, the width of the shielding member is close to the area that the protrusion can press, and the edge of the shielding member can be effectively pressed.

[0021] In some embodiments, the shielding member includes a first surface and a second surface opposite to each other, the protrusion presses against the first surface, the contact area between the first surface and the protrusion is S1, the area of ​​the first surface is S2, and S1 and S2 satisfy:

[0022] 20%≤S1 / S2≤80%.

[0023] Thus, within this range, the protrusion can effectively press against the first surface, thereby stably limiting the position of the shielding member, reducing the probability of the shielding member being freed to other positions as the electrolyte flows, and allowing the shielding member to continuously cover the weak portion. In addition, the electrolyte can flow in the area where the protrusion and the first surface are not in contact. When the pressure in the housing reaches a certain value, the electrolyte can impact the shielding member and further impact the weak portion, allowing the weak portion to open.

[0024] In some embodiments, along the thickness direction of the first wall, the projection of the pressing member completely covers the projection of the shielding member.

[0025] In this way, along the thickness direction of the first wall, the projection of the pressure piece completely covers the projection of the shielding piece, which makes the shielding piece always within the coverage range of the pressure piece, so that the pressure piece can effectively reduce the impact of the electrolyte on the shielding piece, thereby reducing the probability of the shielding piece drifting to other positions with the flow of the electrolyte, so that the shielding piece can continuously cover the weak part.

[0026] In some embodiments, the shielding member has a contact area that contacts the pressing member, and the contact area is spaced apart from the weak portion along a direction perpendicular to the thickness of the first wall.

[0027] In this way, the contact area is spaced from the weak portion along a direction perpendicular to the thickness of the first wall, which can reduce the probability of the pressing member contacting the weak portion, thereby reducing the probability of the pressing member applying pressure to the weak portion, and further reducing the probability of the weak portion opening prematurely under the pressure of the pressing member.

[0028] In some embodiments, the covering member includes a first part, a second part and a bonding structure disposed on the second part, the first part is connected to the second part, the first part covers at least part of the weak portion along the thickness direction of the first wall, the second part is bonded to the first wall through the bonding structure, and the pressing member presses the second part.

[0029] In this way, the first part covers at least part of the weak part along the thickness direction of the first wall, providing protection for the weak part. The second part is bonded to the first wall through the bonding structure, so that the shielding member can form a relatively stable connection with the first wall. The pressing member presses the second part to further enhance the connection stability between the shielding member and the first wall.

[0030] In certain embodiments, the bonding structure protrudes from the surface of the second portion, and the bonding structure and the first portion together form a gas channel, and the gas channel extends to the edge of the shielding member.

[0031] In this way, the gas inside the shell can flow to the weak part through the gas channel, so that the weak part can be opened when the pressure inside the shell reaches a certain value, thereby improving the functional stability of the weak part. In addition, the setting of the gas channel also facilitates the detection of the welding condition of the weak part.

[0032] In some embodiments, the pressing member includes a width edge, and along the length direction of the covering member, the bonding structure includes a first edge and a second edge opposite to the first edge, the first edge is close to the width edge relative to the second edge, the distance between the first edge and the second edge is A1, and the distance between the first edge and the width edge is A2, and A1 and A2 satisfy: 10%≤A1 / A2≤80%.

[0033] In this way, the pressing member can effectively press the shielding member, and further press the area where the bonding structure bonds the shielding member and the first wall, thereby improving the connection strength between the shielding member and the first wall.

[0034] In some embodiments, the battery cell includes an electrode assembly, an insulating film and a connecting sheet, the insulating film wraps the electrode assembly and is located on the side of the pressing member facing away from the first wall, one end of the connecting sheet is connected to the insulating film, the protrusion presses against the other end of the connecting sheet, and the thickness of the shielding member is less than or equal to the thickness of the connecting sheet.

[0035] In this way, the insulating film can reduce the probability of contact between the electrode assembly and the shell, thereby reducing the probability of short circuit of the electrode assembly, thereby improving the reliability of the battery cell. The connecting piece can fix the insulating film, improve the stability of the insulating film wrapped around the electrode assembly, and can connect the insulating film and the pressing piece to reduce the probability of the pressing piece moving with the flow of electrolyte. The thickness of the shielding piece is less than or equal to the thickness of the connecting piece, which can reduce the space occupied by the shielding piece in the thickness direction of the first wall and improve the utilization rate of the internal space of the shell.

[0036] In some embodiments, the housing includes a shell and an end cover plate, the shell is formed with an opening, the end cover plate covers the opening of the shell, and the first wall is located on the shell.

[0037] In this way, the end cover plate can separate the internal environment of the shell from the external environment, avoiding the adverse effect of the external environment on the internal environment. The first wall is located on the shell, so that the weak part has a larger design space, thereby improving the pressure relief effect of the weak part.

[0038] The battery of the embodiment of the utility model includes the battery monomer described in any of the above embodiments.

[0039] Since the battery includes the above-mentioned battery monomer, it at least includes all the beneficial effects of the above-mentioned battery monomer, which will not be described in detail here.

[0040] The electrical equipment of the embodiment of the utility model comprises the battery described in the above embodiment or the battery monomer described in any of the above embodiments.

[0041] Since the electrical equipment includes the above-mentioned battery or battery cell, it at least includes all the beneficial effects of the above-mentioned battery or battery cell, which will not be described in detail here.

[0042] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0044] Figure 1 It is a schematic diagram of the structure of the electrical equipment provided by some embodiments of the utility model;

[0045] Figure 2 It is a schematic diagram of the structure of the battery provided by some embodiments of the utility model;

[0046] Figure 3 is a disassembled diagram of a battery cell provided in some embodiments of the utility model;

[0047] Figure 4 It is a partial schematic diagram of a battery cell provided by some embodiments of the utility model;

[0048] Figure 5 It is a schematic diagram of the structure of the first wall and the weak part provided in some embodiments of the utility model;

[0049] Figure 6 is a cross-sectional view of a first wall, a shielding member, and a pressing member provided in some embodiments of the utility model;

[0050] Figure 7 yes Figure 6 An enlarged view of part a of the cross-sectional view of the first wall, the shielding member and the pressing member;

[0051] Figure 8 It is a disassembly schematic diagram of a pressing member, a shielding member and a weak portion provided in some embodiments of the utility model;

[0052] Fig. 9 It is a schematic diagram of the positional relationship between the pressing member, the shielding member and the weak portion provided in some embodiments of the utility model;

[0053] Fig.10 It is a schematic diagram of the structure of the shielding member provided in some embodiments of the utility model;

[0054] Fig.11 It is a schematic diagram of the projection relationship between the pressing member and the shielding member provided in some embodiments of the utility model;

[0055] Fig.12 It is a schematic diagram of the positional relationship between the pressing member, the shielding member and the weak portion provided in some embodiments of the utility model;

[0056] Fig.13 It is a schematic diagram of the positional relationship between the shielding member and the weak portion provided in some embodiments of the utility model;

[0057] Fig.14 yes Figure 6 An enlarged view of part b of the cross-sectional view of the first wall, the shielding member and the pressing member.

[0058] Description of reference numerals:

[0059] Battery cell 100; outer shell 10; first wall 11; weak part 110; shielding member 20; pressing member 30; opening 31; first groove 111; second groove 112; gas channel 113; plate body 32; protrusion 33; fluid channel 101; first surface 21; second surface 22; contact area 23; first part 24; second part 25; bonding structure 26; width edge 34; first edge 260; second edge 261; first sub-part 250; second sub-part 251; electrode assembly 40; insulating film 50; connecting piece 60; pole 70; adapter plate 80; shell 12; opening 120; end cover plate 13; battery 200; electrical equipment 1000; controller 300; motor 400; battery case 500. DETAILED DESCRIPTION

[0060] The following embodiments of the technical solution of the utility model 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 utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those commonly understood by technicians in the technical field to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" in the specification and claims of the present invention and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0062] In the description of the embodiments of the present utility model, 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 utility model, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0063] 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 invention. 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.

[0064] In the description of the embodiments of the present utility model, 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.

[0065] In the description of the embodiments of the present invention, 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).

[0066] In the description of the embodiments of the present invention, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships 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 invention 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 cannot be understood as a limitation on the embodiments of the present invention.

[0067] In the description of the embodiments of the present utility model, 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, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0068] At present, judging from the development of the market situation, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as aerospace and other fields. With the continuous expansion of battery application fields, its market demand is also constantly expanding.

[0069] During the use of a battery cell, if a short circuit or overcurrent occurs in the battery cell, or if it is impacted by external force, the chemical reaction inside the battery cell will generate a large amount of heat and gas, causing the internal pressure of the battery cell to increase. If the pressure cannot be effectively released, the structure of the battery cell will be damaged or even cause an explosion.

[0070] A weak part can be set at the bottom of the battery cell, and the weak part can be formed by thinning the material at the bottom of the battery cell. The weak part can be an explosion-proof valve, which can sense the pressure change inside the battery. When the pressure reaches a certain value, the explosion-proof valve will open a channel to discharge high-pressure gas and liquid to reduce the pressure inside the battery, thereby reducing the probability of structural damage to the battery cell.

[0071] However, there is electrolyte in the battery cell, and the electrolyte is usually in motion. The electrolyte may be in contact with the explosion-proof valve for a long time, which may cause the explosion-proof valve to be subjected to a certain impact. Furthermore, if the electrolyte flows too fast, the electrolyte will exert a greater impact force on the explosion-proof valve, which may cause the explosion-proof valve to open prematurely, thereby causing the explosion-proof valve to fail.

[0072] In order to solve the problem of functional failure of the explosion-proof valve, a shielding member can be covered on the explosion-proof valve, and the shielding member can cover the explosion-proof valve. However, the shielding member may be freed to other positions of the battery cell along with the electrolyte, resulting in the shielding member being unable to cover the explosion-proof valve. In view of this, the utility model provides a battery cell, in which pressure is applied to the shielding member to prevent the shielding member from being freed to other positions of the battery cell along with the electrolyte, thereby reducing the probability of functional failure of the explosion-proof valve, and further improving the stability of the battery cell.

[0073] The electric device of the embodiment of the utility model includes a battery cell or a battery in any of the following embodiments. Specifically, the electric device can use a battery or a battery cell as a power source, and the electric device can be but not limited to a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc.

[0074] Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc., and spacecraft may include airplanes, rockets, space shuttles and spacecraft, etc.

[0075] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an implementation mode of the utility model.

[0076] Please refer to Figure 1 , Figure 1 1 is a schematic diagram of the structure of the electric device 1000 provided in some embodiments of the present invention. A battery 200 is arranged inside the vehicle, and the battery 200 can be arranged at the bottom, head or tail of the vehicle. The battery 200 can be used to power the vehicle, for example, the battery 200 can be used as an operating power source for the vehicle.

[0077] The vehicle may further include a controller 300 and a motor 400 , wherein the controller 300 is used to control the battery 200 to supply power to the motor 400 , for example, to meet the power requirements for starting, navigating, and driving the vehicle.

[0078] In the embodiment of the utility model, the battery 200 can be used not only as the operating power source of the vehicle, but also as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0079] Please refer to Figure 2 , Figure 2 1 is a schematic diagram of the structure of a battery 200 provided in some embodiments of the present invention. The battery 200 of the embodiment of the present invention comprises a plurality of battery cells 100 of any of the following embodiments.

[0080] In the embodiment of the present invention, the battery cell 100 may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery or a magnesium-ion battery, etc., and the embodiment of the present invention is not limited to this. The battery cell 100 may be cylindrical, flat, rectangular or other shapes, etc., and the embodiment of the present invention is not limited to this. The battery cell 100 is generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiment of the present invention is not limited to this.

[0081] The battery 200 generally includes a battery case 500 for encapsulating one or more battery cells 100. Multiple battery cells 100 can be accommodated in the battery case 500, and the battery case 500 can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells 100. As a carrier of the battery cells 100, the battery case 500 plays a key role in the reliability of the battery cells 100. The battery case 500 must meet the strength and stiffness requirements and the protection level requirements of the electrical equipment housing, while providing collision protection.

[0082] The shape of the battery box 500 can be a cuboid, a cube, etc. The battery box 500 can be cast with materials such as steel plates and aluminum alloys; it can also be made of new lightweight materials, such as glass fiber reinforced composite materials, carbon fiber reinforced composite materials, etc.

[0083] In some embodiments, the battery 200 may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0084] See also Figure 3 , Figure 3 1 is a disassembled diagram of a battery cell 100 provided in some embodiments of the present invention. In some embodiments, the battery cell 100 includes a housing 12 and an electrode assembly 40 , wherein the electrode assembly 40 is disposed in the housing 12 .

[0085] The electrode assembly 40 is a component where an electrochemical reaction occurs in the battery cell 100. One or more electrode assemblies 40 may be contained in the housing 12 of the battery cell 100.

[0086] See also Figure 4 , Figure 5 , Figure 6 and Figure 7 , Figure 4 is a partial schematic diagram of a battery cell 100 provided in some embodiments of the present utility model; Figure 5 It is a schematic structural diagram of the first wall 11 and the weak portion 110 provided in some embodiments of the utility model; Figure 6 is a cross-sectional view of the first wall 11, the shielding member 20 and the pressing member 30 provided in some embodiments of the utility model; Figure 7 yes Figure 6 An enlarged view of part a of the cross-sectional view of the first wall 11, the shielding member 20 and the pressing member 30.

[0087] The battery cell 100 of the embodiment of the utility model comprises a housing 10, a shielding member 20 and a pressing member 30. The housing 10 has a first wall 11, and the first wall 11 is provided with a weak portion 110; the shielding member 20 is arranged in the housing 10, and the shielding member 20 covers at least part of the weak portion 110 along the thickness direction h of the first wall 11; the pressing member 30 is located on the side of the shielding member 20 away from the first wall 11, and the pressing member 30 presses the shielding member 20.

[0088] Specifically, the housing 10 is a structure that forms the outer contour of the battery cell 100. The interior of the housing 10 can be used to accommodate various components of the battery cell 100. The housing 10 may include a plurality of walls with a certain thickness. The first wall 11 is any wall of the housing 10, which may be a top wall, a bottom wall or a side wall.

[0089] The first wall 11 is provided with a weak portion 110, which is used to rupture when the temperature or pressure inside the housing 10 of the battery cell 100 exceeds a threshold value to relieve the pressure of the battery cell 100. The weak portion 110 can be formed by thinning the material, for example, by scoring or grooving the first wall 11. On the first wall 11, the thickness of the area around the thinned portion is greater than the thickness at the thinned portion.

[0090] In some embodiments, the weak portion 110 includes a notch, which may be linear, and the shielding member 20 may shield part or all of the weak portion 110. When the internal temperature or pressure of the battery cell 100 exceeds a threshold, the weak portion 110 is torn open at the notch, thereby achieving pressure relief.

[0091] In some embodiments, the thinned portion may also be an explosion-proof valve installed on the housing 10. The explosion-proof valve may be a closed ring, such as a circular ring, a rectangular ring, etc., and the inner area surrounded by it and the annular area where the explosion-proof valve itself is located form a pressure relief zone, or the inner area surrounded by it, the area where the explosion-proof valve itself is located, and the area within a certain range outside the explosion-proof valve form a pressure relief zone.

[0092] When the internal temperature or pressure of the housing 10 exceeds a threshold, the explosion-proof valve is partially or completely torn, so that the pressure relief area is flipped up relative to other areas of the first wall 11 or the pressure relief area is separated from the first wall 11 to achieve faster pressure relief.

[0093] The explosion-proof valve may also be a non-closed ring, such as a C-shaped ring structure. The area surrounded by the ring or quasi-ring corresponding to the C-shaped ring structure, or the area within a certain range outside the ring or quasi-ring forms a pressure relief zone.

[0094] When the internal temperature or pressure of the housing 10 exceeds a threshold value, the explosion-proof valve is partially or completely torn, so that the pressure relief area is turned up relative to other areas of the first wall 11 to achieve pressure relief more quickly.

[0095] The shielding member 20 may be made of insulating material, for example, the shielding member 20 may include a portion made of PET (Polyethyleneterephthalate). Along the thickness direction h of the first wall 11, the shielding member 20 covers at least a portion of the weak portion 110, and covering means that the shielding member 20 covers the surface of the weak portion 110, or the shielding member 20 is spaced from the weak portion 110, but the orthographic projection of the shielding member 20 on the first wall 11 covers the weak portion 110.

[0096] In some embodiments, the shielding member 20 is connected to the inner wall of the housing 10 . For example, the shielding member 20 may be connected to the first wall 11 of the housing 10 , or may be connected to other inner walls.

[0097] In some embodiments, the shielding member 20 is connected to the first wall 11 of the outer shell 10. Since the weak portion 110 is arranged on the first wall 11 and the shielding member 20 is also connected to the first wall 11, the shielding member 20 occupies a smaller space in the outer shell 10 while satisfying the requirement of covering the weak portion 110.

[0098] Furthermore, since the shielding member 20 is disposed inside the housing 10, the shielding member 20 covers the inner side of the weak portion 110, that is, the shielding member 20 separates the partially shielded weak portion 110 from the electrolyte, thereby preventing the electrolyte from directly contacting the weak portion 110, thereby protecting the weak portion 110 to a certain extent.

[0099] The pressing member 30 is used to apply pressure to stabilize the position of the shielding member 20 so that the shielding member 20 can effectively cover the weak portion 110. The pressing member 30 can be a bottom support plate of the battery cell 100. Since the bottom support plate is a structural member located at the bottom of the housing 10 of the battery cell 100, there is no need to add additional parts in the housing 10, thereby avoiding the additional space occupation caused by the setting of the pressing member 30.

[0100] The bottom support plate supports the electrode assembly 40 of the battery cell 100 and helps maintain the structural integrity of the electrode assembly 40. In this way, the pressure exerted by the bottom support plate on the shielding member 20 is at least the sum of the weight of the bottom support plate and the electrode assembly 40, so that the position of the shielding member 20 can be more effectively stabilized.

[0101] Of course, the pressing member 30 can also be an independently manufactured component. After manufacturing, the pressing member 30 is placed on the side of the shielding member 20 away from the first wall 11 , and the pressing member 30 presses the shielding member 20 to limit the position of the shielding member 20 .

[0102] See also Figure 8 , Figure 8 1 is a disassembled schematic diagram of the pressing member 30, the shielding member 20 and the weak portion 110 provided in some embodiments of the utility model. In some embodiments, the pressing member 30 may be provided with a plurality of openings 31, and the openings 31 may be through holes that penetrate the pressing member 30 along the thickness direction of the pressing member 30. The thickness direction of the pressing member 30 may be the same as the thickness direction h of the first wall 11.

[0103] After the shielding member 20 is pressed by the pressing member 30, a small gap may exist between the shielding member 20 and the pressing member 30. Due to the small gap, the electrolyte may have difficulty in contacting the shielding member 20, which will result in the electrolyte impacting the pressing member 30 instead of the shielding member 20 when the pressure inside the housing 10 exceeds the threshold, and the electrolyte may not impact the weak part 110, and the weak part 110 may not open, resulting in the functional failure of the weak part 110, that is, the failure of the pressure relief function. The setting of the opening 31 is conducive to the contact between part of the electrolyte and the shielding member 20, reducing the probability of the functional failure of the weak part 110.

[0104] In the battery cell 100 of the embodiment of the utility model, the weak portion 110 can be opened when the pressure in the housing 10 reaches a certain value, so as to reduce the pressure in the housing 10, thereby reducing the probability of structural damage to the battery cell 100. The shielding member 20 can reduce the impact of the electrolyte on at least part of the weak portion 110 in the thickness direction h of the first wall 11, thereby reducing the probability of the weak portion 110 opening prematurely due to the impact of the electrolyte to a certain extent. The pressing member 30 can apply a certain force to the shielding member 20, thereby limiting the position of the shielding member 20, reducing the probability of the shielding member 20 being free to other positions with the flow of the electrolyte, so that the shielding member 20 can continuously cover the weak portion 110.

[0105] See also Figure 6 and Figure 7 In some embodiments, the first wall 11 has a first groove 111 and a second groove 112. The first groove 111 extends from the outer surface of the first wall 11 along the thickness direction h of the first wall 11 to the inner surface of the first wall 11. The second groove 112 passes through the bottom surface of the first groove 111 and the inner surface of the first wall 11. The weak portion 110 is arranged in the first groove 111.

[0106] Specifically, the first groove 111 and the second groove 112 can be formed by eliminating part of the material on the first wall 11. The bottom wall of the first groove 111 can be provided with the first groove 111, and the bottom wall of the first groove 111 can be provided with a notch to form a weak portion 110. The provision of the first groove 111 reduces the thickness of the region of the first wall 11 provided with the weak portion 110, so as to facilitate pressure relief through the weak portion 110.

[0107] In this way, the setting of the first groove 111 and the second groove 112 is conducive to thinning the first wall 11. The weak portion 110 is set in the first groove 111, so that the weak portion 110 can be opened in time when the pressure in the shell 10 reaches a certain value, thereby improving the functional stability of the weak portion 110.

[0108] In some embodiments, the first wall 11 is provided with a through hole penetrating the first wall 11. The weak portion 110 may be an explosion-proof valve disc, which may be installed in the through hole, and the explosion-proof valve disc and the first wall 11 may be welded and fixed. The explosion-proof valve disc may be provided with notches, so that the explosion-proof valve disc can be opened in time when the pressure in the housing 10 reaches a certain value, thereby improving the functional stability of the explosion-proof valve disc.

[0109] See also Figure 7 and Figure 8 In some embodiments, the pressing member 30 includes a plate body 32 and a protrusion 33 disposed on the plate body 32 . The protrusion 33 presses against the shielding member 20 . The protrusion 33 is used to form a fluid channel 101 .

[0110] Specifically, the plate body 32 may be a plate of a regular shape, such as a square plate, or a plate of an irregular shape. The protrusion 33 may be a protrusion or structure located on the plate body 32. The protrusion 33 may be integrally formed with the plate body 32, or the protrusion 33 may be separately formed from the plate body 32. The shape of the protrusion 33 may be a regular shape, such as a rectangular parallelepiped, or an irregular shape. The number of protrusions 33 and the plate body 32 may correspond one to one, or may be many to one, that is, multiple protrusions 33 correspond to one plate body 32. The shape and number of the protrusions 33 may be designed as needed, and the embodiments of the utility model do not limit this.

[0111] The fluid channel 101 may be a channel defined between the protrusions 33 and the protrusions 33. It is understood that the plate body 32 may have a plurality of protrusions 33. There is a gap between the protrusions 33 and the protrusions 33, and the gap is the fluid channel 101. The fluid channel 101 may also be a channel defined between the protrusions 33 and the inner wall of the housing 10. It is understood that there may be a gap between the protrusions 33 and the inner wall, and the gap is the fluid channel 101.

[0112] The fluid may be a gas or an electrolyte. The fluid channel 101 may disperse the impact force of the electrolyte, thereby reducing the probability that the shielding member 20 moves to other locations along with the flow of the electrolyte, so that the shielding member 20 can continuously cover the weak portion 110 .

[0113] The fluid channel 101 can also serve as a channel for gas to pass through. When the pressure inside the housing 10 exceeds a threshold, the gas inside the housing 10 can pass through the fluid channel 101, thereby impacting the shielding member 20 and further impacting the weak portion 110 to achieve a pressure relief function.

[0114] In this way, the protrusion 33 can press the shielding member 20 to reduce the probability that the shielding member 20 moves to other positions with the flow of the electrolyte, so that the shielding member 20 can continuously cover the weak portion 110. The fluid channel 101 can allow part of the electrolyte to flow between the shielding member 20 and the pressing member 30. When the pressure in the housing 10 reaches a certain value, the electrolyte can impact the shielding member 20 and further impact the weak portion 110, so that the weak portion 110 can be opened.

[0115] See also Figure 8 In some embodiments, there are multiple protrusions 33 , which are arranged along the width direction T of the pressing member 30 , at least one protrusion 33 presses against the shielding member 20 , and a fluid channel 101 is formed between the multiple protrusions 33 .

[0116] Specifically, the number of the protrusions 33 may be two, three, four, or even more. A plurality of protrusions 33 may be arranged at intervals on the plate body 32, and a plurality of gaps may be formed between the plurality of protrusions 33, and the plurality of gaps may serve as channels for fluid to pass through, i.e., fluid channels 101. The width direction T of the pressing member 30 may be perpendicular to the length direction V of the shielding member 20.

[0117] In this way, the plurality of protrusions 33 can increase the contact area between the pressing member 30 and the shielding member 20, so that the pressing member 30 can effectively press the shielding member 20. The fluid channel 101 formed between the plurality of protrusions 33 can make part of the electrolyte flow along a predetermined flow path, so that the flow behavior of the electrolyte can be more accurately controlled. When the pressure in the housing 10 reaches a certain value, the electrolyte impacts the shielding member 20 along the predetermined flow path, and further impacts the weak portion 110, so that the weak portion 110 can be opened.

[0118] The plurality of protrusions 33 may all press against the shielding member 20, and the area of ​​each protrusion 33 pressing against the shielding member 20 may be equal or unequal. Figure 8 and Fig. 9 , Fig. 9 Schematic diagram of the positional relationship between the pressing member 30, the shielding member 20 and the weak portion 110 provided by some embodiments of the present invention. In some embodiments, the plurality of protrusions 33 press against the shielding member 20, and the area of ​​each protrusion 33 pressing against the shielding member 20 is equal.

[0119] Specifically, the number of protrusions 33 may be four, and the areas of the surfaces of the four protrusions 33 facing the shielding member 20 may be the same, and the surfaces of the four protrusions 33 facing the shielding member 20 may completely press against the shielding member 20. The areas of the four protrusions 33 pressing against the shielding member 20 may be P1, P2, P3, and P4, respectively. Among them, P1, P2, P3, and P4 are all equal.

[0120] It is worth noting that the number of protrusions 33 here is only an example and cannot be understood as a limitation on the implementation methods of the present utility model.

[0121] In this way, the area of ​​each protrusion 33 pressing against the shielding member 20 is equal, which ensures that the pressure on the shielding member 20 is evenly distributed and does not cause uneven pressure due to a protrusion 33 being too large or too small. This helps to improve the stability of the shielding member 20 and helps to evenly distribute the electrolyte around the weak portion 110.

[0122] See also Figure 7 and Fig.10 , Fig.10Schematic diagram of the structure of the shielding member 20 provided in some embodiments of the utility model. In some embodiments, the shielding member 20 includes a first surface 21 and a second surface 22 facing each other, the protrusion 33 presses against the first surface 21, the contact area between the first surface 21 and the protrusion 33 is S1, the area of ​​the first surface 21 is S2, and S1 and S2 satisfy: 20%≤S1 / S2≤80%.

[0123] For example, 25%≤S1 / S2≤80%, 25%≤S1 / S2≤75%, 30%≤S1 / S2≤60%, 20%≤S1 / S2≤60%, 20%≤S1 / S2≤75%, etc.; S1 / S2=20%, S1 / S2=25%, S1 / S2=30%, S1 / S2=60%, S1 / S2=80%, etc.

[0124] Specifically, the first surface 21 may be a surface on the shielding member 20 that is away from the weak portion 110. The first surface 21 may be a plane, a curved surface, or a combination of a plane and a curved surface. The second surface 22 may be a surface on the shielding member 20 that faces the weak portion 110. A portion of the second surface 22 may cover the weak portion 110, and another portion of the second surface 22 may be in contact with the first wall 11. The second surface 22 may be a plane, a curved surface, or a combination of a plane and a curved surface.

[0125] The shielding member 20 may be a thin sheet structure, and the first surface 21 may be located above the second surface 22 along the thickness direction of the shielding member 20. The protrusion 33 can apply pressure to the first surface 21, so that the second surface 22 is closely attached to the first wall 11, so that the relative position between the second surface 22 and the first wall 11 remains substantially unchanged. The thickness direction of the shielding member 20 and the thickness direction h of the first wall 11 may be the same.

[0126] Thus, within this range, the protrusion 33 can effectively press against the first surface 21, thereby stably limiting the position of the shielding member 20, reducing the probability of the shielding member 20 being freed to other positions with the flow of the electrolyte, so that the shielding member 20 can continuously cover the weak portion 110. In addition, the electrolyte can flow in the area where the protrusion 33 and the first surface 21 are not in contact. When the pressure in the housing 10 reaches a certain value, the electrolyte can impact the shielding member 20, and further impact the weak portion 110, so that the weak portion 110 can be opened.

[0127] See also Figure 8 and Fig.11 , Fig.11 Schematic diagram of the projection relationship between the pressing member 30 and the shielding member 20 provided in some embodiments of the present invention. In some embodiments, along the thickness direction h of the first wall 11 , the projection T1 of the pressing member 30 completely covers the projection T2 of the shielding member 20 .

[0128] Specifically, the shape of the pressing member 30 can match the shape of the shielding member 20, so that the shielding member 20 can be located in the area covered by the pressing member 30, so that the edge of the shielding member 20 is not prone to warping, flanging, etc., so that the pressing member 30 can effectively press the shielding member 20. For example, along the thickness direction h of the first wall 11, the surface of the pressing member 30 facing the shielding member 20 can be rectangular, the surface of the shielding member 20 facing the pressing member 30 can be rectangular, and the area of ​​the surface of the pressing member 30 facing the shielding member 20 can be larger than the area of ​​the surface of the shielding member 20 facing the pressing member 30, that is, the projection T1 of the pressing member 30 completely covers the projection T2 of the shielding member 20.

[0129] In this way, along the thickness direction h of the first wall 11, the projection T1 of the pressing member 30 completely covers the projection T2 of the shielding member 20, which makes the shielding member 20 always within the coverage range of the pressing member 30, so that the pressing member 30 can effectively reduce the impact of the electrolyte on the shielding member 20, thereby reducing the probability of the shielding member 20 drifting to other positions with the flow of the electrolyte, so that the shielding member 20 can continuously cover the weak portion 110.

[0130] See also Fig.12 , Fig.12 Schematic diagram of the positional relationship of the pressing member 30, the shielding member 20 and the weak portion 110 provided in some embodiments of the utility model. In some embodiments, the shielding member 20 has a contact area 23 in contact with the pressing member 30, and the contact area 23 is spaced from the weak portion 110 along a direction perpendicular to the thickness of the first wall 11.

[0131] Specifically, the contact area 23 is a portion of the shielding member 20 that directly contacts the pressing member 30. The pressing member 30 presses against the contact area 23, and the pressing member 30 applies pressure to the contact area 23 so that the relative position between the shielding member 20 and the first wall 11 can remain substantially unchanged.

[0132] The shielding member 20 may be a thin sheet structure, and the thickness direction of the shielding member 20 may be the same as the thickness direction h of the first wall 11. The direction perpendicular to the thickness of the first wall 11 may be the length direction V or the width direction of the shielding member 20. For example, the contact area 23 is spaced apart from the weak portion 110 along the length direction V of the shielding member 20.

[0133] In this way, the contact area 23 is spaced apart from the weak portion 110 along a direction perpendicular to the thickness of the first wall 11, which can reduce the probability of the pressing member 30 contacting the weak portion 110, thereby reducing the probability of the pressing member 30 applying pressure to the weak portion 110, and further reducing the probability of the weak portion 110 opening prematurely under the pressure of the pressing member 30.

[0134] See also Fig.12In some embodiments, the width of the weak portion 110 is W1, and along the width direction T of the pressing member 30, the farthest distance of the plurality of protrusions 33 is W2, and W1 and W2 satisfy: W2≥W1+4, in mm.

[0135] Specifically, along the width direction T of the pressing member 30 , the farthest distance between the plurality of protrusions 33 is the distance between the edges of the two protrusions 33 at the outermost sides.

[0136] In this way, the area where the protrusion 33 presses the shielding member 20 can be distributed outside the weak portion 110, so that the shielding member 20 can be effectively pressed.

[0137] See also Fig.12 In some embodiments, along the width direction T of the pressing member 30, the farthest distance between the plurality of protrusions 33 is W2, the width of the shielding member 20 is W3, and W2 and W3 satisfy: 0≤|W3-W2|≤10, in mm. In this way, the width W3 of the shielding member 20 is close to the area that the protrusions 33 can press, and the edge of the shielding member 20 can be effectively pressed.

[0138] See also Figure 7 and Figure 8 In some embodiments, the shielding member 20 includes a first part 24, a second part 25 and a bonding structure 26 disposed on the second part 25, the first part 24 is connected to the second part 25, the first part 24 covers at least part of the weak portion 110 along the thickness direction h of the first wall 11, the second part 25 is bonded to the first wall 11 through the bonding structure 26, and the pressing member 30 presses the second part 25.

[0139] Specifically, the first portion 24 is used to resist the electrolyte. When the pressure inside the housing 10 does not exceed the threshold, the first portion 24 can reduce the direct effect of the electrolyte on the weak portion 110, thereby reducing the probability of the weak portion 110 opening prematurely.

[0140] The second part 25 can be integrally formed with the first part 24, or can be separately formed from the first part 24. The shielding member 20 includes a bonding structure 26 disposed on the second part 25, and the second part 25 can be bonded to the first wall 11 through the bonding structure 26. The bonding structure 26 can protrude from the surface of the second part 25, and the bonding structure 26 can be made of a material such as epoxy glue, silicone glue, etc. that can adapt to the internal environment of the housing 10. The internal environment of the housing 10 includes electrolyte, temperature, etc.

[0141] Furthermore, before bonding, the surfaces of the first wall 11 and the second part 25 may be properly treated to enhance the bonding performance and improve the bonding adhesion. For example, the surfaces of the first wall 11 and the second part 25 may be cleaned, dirt removed, polished, and the like.

[0142] In this way, the first portion 24 covers at least part of the weak portion 110 along the thickness direction h of the first wall 11, providing protection for the weak portion 110. The second portion 25 is bonded to the first wall 11 via the bonding structure 26, so that the shielding member 20 can form a relatively stable connection with the first wall 11. The pressing member 30 presses against the second portion 25, thereby further enhancing the connection stability between the shielding member 20 and the first wall 11.

[0143] See also Fig.13 , Fig.13 Schematic diagram of the positional relationship between the shielding member 20 and the weak portion 110 provided in some embodiments of the utility model. In some embodiments, the weak portion 110 can separate the second portion 25 into two spaced areas, namely, the first sub-portion 250 and the second sub-portion 251. In the direction perpendicular to the thickness of the first wall 11, the length L1 of the first sub-portion 250 and the length L2 of the second sub-portion 251 are equal to ensure uniform bonding and avoid defects such as warping or flanging of one of the first sub-portion 250 and the second sub-portion 251.

[0144] See also Figure 7 In some embodiments, the bonding structure 26 protrudes from the surface of the second portion 25 , and the bonding structure 26 and the first portion 24 together form a gas channel 113 , and the gas channel 113 extends to the edge of the shielding member 20 .

[0145] Specifically, the second portion 25 may be connected to both ends of the first portion 24, and the second portion 25 may be coplanar with the first portion 24. The gas channel 113 may be communicated with the second groove 112, and the gas channel 113 may be covered by the first portion 24.

[0146] In this way, the gas inside the housing 10 can flow to the weak portion 110 through the gas channel 113, so that the weak portion 110 can be opened when the pressure inside the housing 10 reaches a certain value, thereby improving the functional stability of the weak portion 110. In addition, the provision of the gas channel 113 also facilitates the detection of the welding condition of the weak portion 110.

[0147] See also Fig.12 In some embodiments, the pressing member 30 includes a width edge 34. Along the length direction V of the shielding member 20, the bonding structure 26 includes a first edge 260 and a second edge 261 opposite to the first edge 260. The first edge 260 is closer to the width edge 34 relative to the second edge 261. The distance between the first edge 260 and the second edge 261 is A1, and the distance between the first edge 260 and the width edge 34 is A2. A1 and A2 satisfy: 10%≤A1 / A2≤80%.

[0148] For example, the relationship between A1 and A2 may be 10%≤A1 / A2≤75%, 15%≤A1 / A2≤75%, 20%≤A1 / A2≤70%, 20%≤A1 / A2≤60%, 60%≤A1 / A2≤80%, etc. A1 / A2 may be 10%, 15%, 20%, 60%, 80%, etc.

[0149] Specifically, the width edge is the end surface along the length direction of the pressing member 30, and the length direction of the pressing member 30 may be perpendicular to the width direction T of the pressing member 30. In some embodiments, the bonding structure 26 may be symmetrically arranged on the shielding member 20, so A1 and A2 correspond to two sets of values.

[0150] In this way, the pressing member 30 can effectively press the shielding member 20 , and further press the region where the bonding structure 26 bonds the shielding member 20 and the first wall 11 , thereby improving the connection strength between the shielding member 20 and the first wall 11 .

[0151] See also Figure 3 In some embodiments, the battery cell 100 includes an electrode assembly 40, an insulating film 50 and a connecting sheet 60, the insulating film 50 wraps the electrode assembly 40 and is located on the side of the pressing member 30 away from the first wall 11, one end of the connecting sheet 60 is connected to the insulating film 50, the protrusion 33 presses the other end of the connecting sheet 60, and the thickness of the shielding member 20 is less than or equal to the thickness of the connecting sheet 60. The thickness of the shielding member 20 is the maximum thickness of the entire shielding member 20.

[0152] Specifically, the electrode assembly 40 is a component in the battery cell 100 where an electrochemical reaction occurs. The housing 10 may contain one or more electrode assemblies 40. The electrode assembly 40 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The portion of the positive electrode sheet and the negative electrode sheet with active material constitutes the electrode body of the electrode assembly 40, and the portion of the positive electrode sheet and the negative electrode sheet without active material each constitutes a pole ear.

[0153] The insulating film 50 is used to isolate the electrode assembly 40 from the inner wall of the housing 10 to reduce the probability of a short circuit caused by direct contact between the electrode assembly 40 and the inner wall. The insulating film 50 can be a polyester film, a polypropylene film, or a polyethylene film. For example, the insulating film 50 can be a polyester film, which has excellent electrical insulation properties, mechanical properties, and heat resistance, and can effectively reduce the probability of a short circuit in the electrode assembly 40.

[0154] The connecting sheet 60 may have a surface connected to the insulating film 50, and the surface may be connected to the insulating film 50 by bonding. One end of the connecting sheet 60 may be used to fix the insulating film 50, so that the insulating film 50 can continuously wrap the electrode assembly 40, thereby reducing the probability of functional failure of the insulating film 50. The other end of the connecting sheet 60 may be connected to the pressing member 30 by bonding, and can be pressed by the pressing member 30, thereby fixing the connecting sheet 60.

[0155] Since one end of the connecting piece 60 is fixed to the side of the pressing member 30 facing the first wall 11, the connecting piece 60 occupies a certain space inside the housing 10 in the thickness direction h of the first wall 11. The shielding member 20 and the end of the connecting piece 60 fixed to the pressing member 30 can be arranged on the same surface of the pressing member 30, and the thickness of the shielding member 20 is set to be less than or equal to the thickness of the connecting piece 60, which can reduce the space occupied by the shielding member 20 in the thickness direction h of the first wall 11 and improve the utilization rate of the internal space of the housing 10.

[0156] See also Figure 6 , Figure 7 and Fig.14 , Fig.14 yes Figure 6 The enlarged view of the b part of the cross-sectional view of the first wall 11, the shielding member 20 and the pressing member 30. The thickness B1 of the shielding member 20 can be 0.01mm-3mm, 0.05mm-2.5mm, 0.1mm-2mm, 0.5mm-1mm, 0.01mm-0.3mm, etc.; the thickness B1 of the shielding member 20 can be 0.01mm, 0.05mm, 0.1mm, 0.3mm, 3mm. The thickness B2 of the connecting piece 60 can be 0.01-5mm, 0.05-4.5mm, 0.1-4mm, 0.2-3mm, 0.3-0.5mm, etc., and the thickness B2 of the connecting piece 60 can be 0.01mm, 0.2mm, 0.3mm, 0.5mm, 5mm, etc.

[0157] Within these ranges, the shielding member 20 and the connecting piece 60 are easy to manufacture, the shielding member 20 can effectively protect the weak portion 110 , and the connecting piece 60 can effectively stabilize the insulating film 50 .

[0158] In this way, the insulating film 50 can reduce the probability of the electrode assembly 40 contacting the housing 10, thereby reducing the probability of the electrode assembly 40 short-circuiting, thereby improving the reliability of the battery cell 100. The connecting piece 60 can fix the insulating film 50, improve the stability of the insulating film 50 wrapping the electrode assembly 40, and can connect the insulating film 50 and the pressing member 30, reducing the probability of the pressing member 30 moving with the flow of the electrolyte. The thickness of the shielding member 20 is less than or equal to the thickness of the connecting piece 60, which can reduce the space occupied by the shielding member 20 in the thickness direction h of the first wall 11 and improve the utilization rate of the internal space of the housing 10.

[0159] See also Figure 3 In some embodiments, the housing 10 includes a shell 12 and an end cover plate 13 . The shell 12 is formed with an opening 120 . The end cover plate 13 covers the opening 120 of the shell 12 . The first wall 11 is located on the shell 12 .

[0160] Specifically, the end cover plate 13 refers to a component that covers the opening 120 of the shell 12 to isolate the interior of the shell 10 from the external environment. The shell 12 is a structure of the shell 10 for accommodating components such as the electrode assembly 40. The shape of the opening 120 of the shell 12 can be a regular shape, such as a square, or an irregular shape.

[0161] The battery cell 100 further includes a pole 70, which is used to be electrically connected to the electrode assembly 40 to output or input the electric energy of the battery cell 100. The pole 70 includes a positive pole and a negative pole, and the positive pole and the negative pole are arranged on the end cover plate 13 at intervals in the length direction of the battery cell 100. The length direction of the battery cell 100 may be the same as the length direction V of the shielding member 20.

[0162] During the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs are electrically connected to the pole 70 to form a current loop. The tabs include positive tabs and negative tabs. The positive tabs are used to connect to the positive pole, and the negative tabs are used to connect to the negative pole.

[0163] The battery cell 100 further includes an adapter plate 80 , wherein the positive electrode tab is connected to the positive electrode column via one adapter plate 80 , and the negative electrode tab is connected to the negative electrode column via another adapter plate 80 .

[0164] The first wall 11 may be a wall located in the bottom area of ​​the housing 12. The weak portion 110 may be specifically provided on a wall plate in the housing 12 opposite to the end cover plate 13, or may be provided on other side walls of the housing 12, and the wall plate provided with the weak portion 110 is the first wall 11. When the housing 10 is provided with weak portions 110 on different side walls, that is, when the housing 10 is provided with a plurality of weak portions 110, the shielding member 20 at least shields at least a portion of the weak portion 110 located on the bottom wall plate of the housing 10.

[0165] In this way, the end cover plate 13 can separate the internal environment of the shell 12 from the external environment to avoid the adverse effect of the external environment on the internal environment. The first wall 11 is located on the shell 12, so that the weak part 110 has a larger design space, thereby improving the pressure relief effect of the weak part 110.

[0166] In other embodiments, the weak portion 110 may be disposed on the end cover plate 13 , thereby facilitating replacement of the weak portion 110 .

[0167] See also Figure 3 , Figure 4 , Figure 5 and Figure 8 In a specific embodiment, the battery cell 100 includes a housing 10, a shielding member 20 and a pressing member 30. The housing 10 has a first wall 11 disposed at the bottom, and the first wall 11 is provided with a weak portion 110, and the weak portion 110 is an explosion-proof valve. The shielding member 20 is a diaphragm made of PET material, and the surface of the diaphragm facing the first wall 11 can be bonded to the first wall 11. The pressing member 30 is a bottom support plate in the battery cell 100.

[0168] Four protrusions 33 are provided on the bottom support plate, and all of the four protrusions 33 can press against the diaphragm. The areas of the four protrusions 33 pressing against the diaphragm are equal, so as to reduce the probability of the diaphragm being freed to other positions with the flow of electrolyte, so that the diaphragm can continuously cover the explosion-proof valve.

[0169] See also Figure 3 In some embodiments, when the battery cell 100 is in use, the first wall 11 is the bottom wall of the housing 10. Thus, when the battery cell 100 is in use, the shielding member 20 shields the weak portion 110, thereby reducing the probability that the shielding member 20 is freed to other positions due to the impact of the electrolyte on the bottom wall of the housing 10.

[0170] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it; although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above 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 utility model, and they should all be included in the scope of the claims and description of the utility model. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The utility model 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: A housing, the housing having a first wall, the first wall being provided with a weak portion; a shielding member, the shielding member being disposed in the housing and covering at least a portion of the weak portion along a thickness direction of the first wall; and A pressing member is located at a side of the shielding member away from the first wall, and presses the shielding member.

2. The battery cell according to claim 1, characterized in that: The pressing member includes a plate body and a protrusion arranged on the plate body, the protrusion presses the shielding member, and the protrusion is used to form a fluid channel.

3. The battery cell according to claim 2, characterized in that: There are multiple protrusions, and the multiple protrusions are arranged along the width direction of the pressing member. At least one protrusion presses the shielding member, and the fluid channel is formed between the multiple protrusions.

4. The battery cell according to claim 3, characterized in that: The plurality of protrusions all press against the shielding member, and the area of ​​each protrusion pressing against the shielding member is equal.

5. The battery cell according to claim 3 or 4, characterized in that: The width of the weak portion is W1, and along the width direction of the pressing member, the farthest distance between the plurality of protrusions is W2, and W1 and W2 satisfy: W2≥W1+4, in mm.

6. The battery cell according to any one of claims 3 to 5, characterized in that: Along the width direction of the pressing member, the farthest distance between the plurality of protrusions is W2, the width of the shielding member is W3, and W2 and W3 satisfy: 0≤|W3-W2|≤10, in mm.

7. The battery cell according to any one of claims 2 to 6, characterized in that: The shielding member includes a first surface and a second surface facing each other, the protrusion presses against the first surface, the contact area between the first surface and the protrusion is S1, the area of ​​the first surface is S2, and S1 and S2 satisfy: 20%≤S1 / S2≤80%.

8. The battery cell according to any one of claims 2 to 6, characterized in that: The battery cell includes an electrode assembly, an insulating film and a connecting sheet. The insulating film wraps the electrode assembly and is located on the side of the pressing member facing away from the first wall. One end of the connecting sheet is connected to the insulating film, and the protrusion presses the other end of the connecting sheet. The thickness of the shielding member is less than or equal to the thickness of the connecting sheet.

9. The battery cell according to any one of claims 1 to 8, characterized in that: Along the thickness direction of the first wall, the projection of the pressing member completely covers the projection of the shielding member.

10. The battery cell according to any one of claims 1 to 9, characterized in that: The shielding member has a contact area that contacts the pressing member, and the contact area is spaced apart from the weak portion along a direction perpendicular to the thickness of the first wall.

11. The battery cell according to any one of claims 1 to 10, characterized in that: The shielding member includes a first part, a second part and a bonding structure arranged on the second part, the first part is connected to the second part, the first part covers at least part of the weak part along the thickness direction of the first wall, the second part is bonded to the first wall through the bonding structure, and the pressing member presses the second part.

12. The battery cell according to claim 11, characterized in that: The bonding structure protrudes from the surface of the second part, and the bonding structure and the first part together form a gas channel, and the gas channel extends to the edge of the shielding member.

13. The battery cell according to claim 12, characterized in that: The first wall has a first groove and a second groove, the first groove extends from the outer surface of the first wall to the inner surface of the first wall along the thickness direction of the first wall, the second groove passes through the bottom surface of the first groove and the inner surface of the first wall, the second groove is connected to the gas channel, and the weak portion is arranged in the first groove.

14. The battery cell according to any one of claims 11 to 13, characterized in that: The pressing member includes a width edge. Along the length direction of the shielding member, the bonding structure includes a first edge and a second edge opposite to the first edge. The first edge is close to the width edge relative to the second edge. The distance between the first edge and the second edge is A1, and the distance between the first edge and the width edge is A2. A1 and A2 satisfy: 10%≤A1 / A2≤80%.

15. The battery cell according to any one of claims 1 to 14, characterized in that: The housing comprises a shell and an end cover plate. The shell is formed with an opening. The end cover plate covers the opening of the shell. The first wall is located on the shell.

16. The battery cell according to any one of claims 1 to 15, characterized in that: When the battery cell is in use, the first wall is the bottom wall of the housing.

17. A battery, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 16.

18. An electrical equipment, characterized in that: The invention comprises the battery cell according to any one of claims 1 to 16 or the battery according to claim 17.

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