Battery cell, battery pack, electric device, and energy storage device

Abstract

A battery cell, a battery pack, an electric device, and an energy storage device, relating to the technical field of batteries. The battery cell comprises a casing (1), an explosion-proof valve (2), a bare cell (3), and elastic pieces (4). The explosion-proof valve (2) is arranged on the casing (1), the bare cell (3) is arranged in the casing (1), and the arrangement direction of the explosion-proof valve (2) and the bare cell (3) is a first direction (3a). In the first direction (3a), the elastic pieces (4) are located between the bare cell (3) and a casing wall on the side of the casing (1) facing the explosion-proof valve (2) in the first direction (3a). When thermal runaway occurs inside the battery cell, the bare cell (3) is driven by airflow to move rapidly towards the explosion-proof valve (2) in the first direction (3a). The elastic pieces (4) can buffer the bare cell (3) to a certain extent, reducing the rigid impact on the bare cell (3), thereby mitigating the short circuit caused by deformation of the bare cell (3) due to external loads.

Description

Battery monomer, battery pack, electric device and energy storage device

[0001] Cross-reference to related applications

[0002] The present disclosure is based on and claims priority to Chinese Patent Application No. 202421422538.7, filed on June 20, 2024, entitled "Battery monomer, battery pack, electric device and energy storage device", the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to the technical field of batteries, and in particular to a battery monomer, a battery cell, a battery pack and an electric device. BACKGROUND

[0004] New energy batteries are increasingly widely used in life and industry. For example, new energy vehicles equipped with batteries have been widely used, and batteries are also increasingly used in energy storage fields and the like.

[0005] In related technologies, when a battery monomer experiences thermal runaway, the battery monomer can short circuit.

[0006] SUMMARY

[0007] To solve the above technical problems, the present disclosure provides a battery monomer, a battery pack and an electric device to alleviate the short circuit of the battery monomer.

[0008] The present disclosure is implemented by the following technical solutions.

[0009] A first aspect of an embodiment of the present disclosure provides a battery monomer, comprising:

[0010] a shell;

[0011] an explosion-proof valve arranged in the shell;

[0012] a bare cell arranged in the shell, and the arrangement direction of the explosion-proof valve and the bare cell being a first direction;

[0013] a resilient member, the resilient member being located between the bare cell and a shell wall of the shell on a side of the shell facing the explosion-proof valve along the first direction.

[0014] In the scheme of the embodiment of the present disclosure, the resilient member is located between the bare cell and the shell wall of the shell on the side of the shell facing the explosion-proof valve along the first direction. When thermal runaway occurs inside the battery monomer, the bare cell will be carried by the airflow and move along the first direction towards the explosion-proof valve. The resilient member can buffer the bare cell to some extent, reducing the rigid impact on the bare cell, thereby alleviating the short circuit caused by the deformation of the bare cell due to external loads.

[0015] In an embodiment, the battery monomer further comprises an insulating piece, the insulating piece is located between the bare cell and the shell wall on the side of the shell along the first direction towards the explosion-proof valve, and the elastic piece is at least partially located on the side of the insulating piece towards the bare cell along the first direction.

[0016] In the scheme of the embodiment of the present disclosure, the battery monomer further comprises an insulating piece, the insulating piece is located between the bare cell and the shell wall on the side of the shell along the first direction towards the explosion-proof valve. The insulating piece can alleviate the short circuit between the bare cell and the shell, and to a certain extent, reduce the rigid collision between the bare cell and the shell, thereby further reducing the short circuit of the bare cell.

[0017] In an embodiment, the insulating piece is formed with a first protrusion, the first protrusion protrudes towards the bare cell along the first direction, and the elastic piece is connected to the side of the first protrusion towards the bare cell.

[0018] In the scheme of the embodiment of the present disclosure, the insulating piece is formed with a first protrusion, the first protrusion protrudes towards the bare cell along the first direction. The first protrusion can increase the size of the insulating piece along the first direction, and the insulating piece can abut against the bare cell through the first protrusion, thereby pressing the bare cell to reduce the movement of the bare cell along the first direction during the operation of the battery monomer.

[0019] In an embodiment, the first protrusion is formed with a avoiding cavity, the tab of the bare cell is located in the avoiding cavity, the first protrusion is arranged around the circumferential direction of the tab, the elastic piece is annular, and the elastic piece is annularly arranged around the tab.

[0020] In the scheme of the embodiment of the present disclosure, the first protrusion is formed with a avoiding cavity, the tab of the bare cell is located in the avoiding cavity, the elastic piece is annular, and the elastic piece is annularly arranged around the tab. The first protrusion is formed with a avoiding cavity to avoid the tab of the bare cell and reduce the situation that the tab is pressed by the insulating piece. The annular arrangement of the elastic piece around the tab can make full use of the space around the tab, and increase the contact area between the elastic piece and the bare cell as much as possible, thereby increasing the buffering effect of the elastic piece and further reducing the short circuit of the bare cell.

[0021] In an embodiment, the number of elastic pieces is two, and the two elastic pieces are respectively located on the two sides of the insulating piece along the second direction, and the second direction is arranged transversely to the first direction.

[0022] In the embodiment of the present disclosure, the number of elastic pieces is two, and the two elastic pieces are respectively located on the two sides of the insulating piece. The interval arrangement of the elastic pieces can balance the blocking effect of the elastic pieces on the bare cell, so that the stress of the bare cell is more uniform.

[0023] In an embodiment, the side of the elastic piece towards the insulating piece is formed with a mounting groove, the opening of the mounting groove faces the insulating piece, and the insulating piece is partially located in the mounting groove.

[0024] In the embodiments of the present disclosure, the elastic member is formed with a mounting groove on the side facing the insulating member, and the opening of the mounting groove faces the insulating member. The insulating member can be connected with the elastic member through the mounting groove, so that the insulating member and the elastic member are connected in one body, and the situation that the elastic member shakes inside the battery monomer can be relieved to some extent, and the elastic member can more stably buffer the bare battery cell during the working process.

[0025] In an embodiment, along the arrangement direction of the explosion-proof valve and the bare battery cell, the size of the elastic member is a target size, the target size ranges from 0.5 mm to 5.0 mm, the contact area of the elastic member and the bare battery cell is a first area, the projection of the arrangement direction of the explosion-proof valve and the bare battery cell, and the area of the projection region of the bare battery cell is a second area, the units of the first area and the second area are the same, the ratio of the first area to the second area is a first ratio, and the range of the first ratio is 5.1% to 44.7%.

[0026] In the embodiments of the present disclosure, the target size and the first ratio are in a suitable range, so that the size of the elastic member is as small as possible under the condition of providing a certain buffering effect, thereby increasing the size of the bare battery cell along the length direction and increasing the energy density of the battery monomer.

[0027] In an embodiment, along the arrangement direction of the explosion-proof valve and the bare battery cell, the size of the elastic member is a target size, the target size ranges from 0.5 mm to 5.0 mm, and the opening pressure of the explosion-proof valve is a target pressure, and the target pressure ranges from 0.5 MPa to 5.5 MPa.

[0028] In the embodiments of the present disclosure, the size of the target pressure can control the load received by the bare battery cell when the bare battery cell moves to the explosion-proof valve in the case of thermal runaway. The target pressure in a suitable range can make the elastic member buffer the bare battery cell more stably, and further, relieve the situation that the explosion-proof valve is opened by the gas generated by the bare battery cell under normal working conditions.

[0029] In an embodiment, the elastic modulus of the elastic member is greater than or equal to 0.1 MPa and less than or equal to 1000 MPa.

[0030] In the embodiments of the present disclosure, the elastic modulus of the elastic member in a suitable range can make the deformation of the elastic member as small as possible under the condition of buffering the bare battery cell, thereby reducing the size of the elastic member along the first direction and reducing the size of the battery monomer along the first direction.

[0031] In an embodiment, the elastic modulus of the elastic member is greater than or equal to 0.5 MPa and less than or equal to 100 MPa.

[0032] In the embodiments of the present disclosure, the elastic modulus of the elastic member can be further increased in a small range to increase the buffering effect of the elastic member on the bare battery cell, and the deformation amount of the elastic member can be controlled in a suitable range.

[0033] In an embodiment, the shell includes a top cover and a shell body connected to each other, the top cover covers the shell body, the explosion-proof valve is arranged on the top cover, one of the elastic member and the top cover is formed with a second protrusion, and the other is formed with a positioning groove, and the second protrusion is at least partially located in the positioning groove to install the elastic member.

[0034] In the embodiments of the present disclosure, the second protrusion and the positioning groove are formed between the top cover and the elastic member to be matched with each other. The elastic member can be quickly installed through the cooperation between the second protrusion and the positioning groove, and the elastic member can be limited to a certain extent to alleviate the shaking of the elastic member inside the battery monomer.

[0035] In an embodiment, the material of the elastic member is an insulating material.

[0036] In the embodiments of the present disclosure, the material of the elastic member is an insulating material, which can reduce the short circuit of the battery monomer during use. The elastic member can replace the insulating member to alleviate the short circuit between the bare battery cell and the shell body, thereby reducing the number of components inside the battery monomer.

[0037] In an embodiment, the elastic member includes an elastic member body and a protective layer connected to each other, the protective layer covers the elastic member body, and the protective layer includes an insulating layer and / or a corrosion-resistant layer, and the corrosion-resistant layer is used to inhibit the corrosion of the elastic member body by the electrolyte.

[0038] In the embodiments of the present disclosure, the elastic member is a multi-layer structure, and the protective layer can alleviate the situation that the bare battery cell directly contacts the external metal to cause short circuit or the situation that the elastic member is corroded by the electrolyte.

[0039] The second aspect of the present disclosure provides a battery pack, comprising:

[0040] a box body;

[0041] The battery monomer of any of the above is arranged in the interior of the box body.

[0042] The third aspect of the embodiments of the present disclosure provides a power utilization device, comprising:

[0043] a device body;

[0044] The battery pack of any of the above is used to supply power to the device body.

[0045] The fourth aspect of the embodiments of the present disclosure provides an energy storage device, comprising:

[0046] a mounting container;

[0047] The battery pack of any one of the above is arranged in the mounting container.

[0048] Inventive Effects:

[0049] In the scheme of the embodiments of the present disclosure, the elastic member is arranged between the bare battery cell and the shell wall on the side of the housing facing the explosion-proof valve in the first direction. When thermal runaway occurs inside the battery monomer, the bare battery cell will be carried by the airflow and will move towards the explosion-proof valve in the first direction. The elastic member can provide a certain buffering effect to the bare battery cell, reducing the rigid impact received by the bare battery cell, thereby relieving the situation that the bare battery cell is deformed due to external load and causes short circuit. BRIEF DESCRIPTION OF DRAWINGS

[0050] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of preferred embodiments and are not meant to limit the present disclosure. Moreover, the same reference numerals in the different drawings represent the same or similar elements. In the drawings:

[0051] FIG. 1 is an exploded view of the structure of a battery monomer according to a first embodiment of the present disclosure;

[0052] FIG. 2 is an assembly diagram of an elastic member and an insulating member according to a second embodiment of the present disclosure;

[0053] FIG. 3 is an assembly diagram of an elastic member and an insulating member according to a third embodiment of the present disclosure;

[0054] FIG. 4 is a structural schematic diagram of a battery monomer according to a fourth embodiment of the present disclosure;

[0055] FIG. 5 is a partial enlarged view of position A in FIG. 4;

[0056] FIG. 6 is an exploded view of the structure of a battery monomer according to a fifth embodiment of the present disclosure;

[0057] FIG. 7 is a structural schematic diagram of a battery monomer according to a sixth embodiment of the present disclosure;

[0058] FIG. 8 is a partial enlarged view of position B in FIG. 7.

[0059] BRIEF DESCRIPTION OF DRAWINGS

[0060] 1, housing; 10, top cover; 10a, positioning groove; 11, shell; 2, explosion-proof valve; 3, bare battery cell; 3a, first direction; 4, elastic member; 4a, second direction; 4b, mounting groove; 4c, second protrusion; 5, insulating member; 5a, first protrusion; 5b, avoiding cavity. DETAILED DESCRIPTION

[0061] The embodiments of the present disclosure will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present disclosure, and therefore only serve as examples, and cannot be used to limit the protection scope of the present disclosure.

[0062] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this present disclosure belongs; the terminology used in the specification herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure; the terms "comprising" and "having," and any variations thereof, as used in the specification and claims herein, are intended to cover both the inclusive and exclusive cases.

[0063] In the description of the embodiments of the present disclosure, the technical terms "first", "second", "third" and the like 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 disclosure, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

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

[0065] In the description of the embodiments of the present disclosure, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents the "or" relationship between the front and rear associated objects.

[0066] In the description of the embodiments of the present disclosure, the technical terms "top", "bottom", "upper", "lower" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present disclosure and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed, operated or used in a particular orientation, and therefore cannot be understood as a limitation of the embodiments of the present disclosure.

[0067] In the description of the embodiments of the present disclosure, unless specifically defined and limited otherwise, the technical terms "mount", "connect", "connect", "fix", and other terms should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or integrated; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0068] In the description of the embodiments of the present disclosure, unless specifically defined and limited otherwise, the technical term "contact" should be understood in a broad sense, which can be direct contact or contact through an intermediate medium layer, which can be contact between two objects in contact without interaction force, or contact between two objects in contact with interaction force.

[0069] In the related art, the shell of the battery monomer is provided with an explosion-proof valve. When the battery monomer is in thermal runaway, the gas in the battery monomer can flow to the outside through the explosion-proof valve, thereby relieving the damage of the battery monomer due to excessive internal gas pressure. However, in the case of thermal runaway of the battery monomer, the internal gas will drive the bare cell to move towards the direction of the explosion-proof valve, so that the bare cell collides with the harder object. The pole piece of the bare cell may be deformed due to external impact, so that the positive pole piece and the negative pole piece are short-circuited, causing the battery monomer to short-circuit. For the laminated cell or the wound cell, the positive pole piece and the negative pole piece of the cell are provided with a separation film to avoid short-circuiting between the negative pole piece and the positive pole piece. In the case of external impact on the bare cell, the separation film may be torn, so that the positive pole piece and the negative pole piece are short-circuited, so that the bare cell is short-circuited.

[0070] Exemplarily, the bare cell 3 collides with the insulating piece 5.

[0071] It can be understood that the bare cell 3 not only collides with the insulating piece 5, but also collides with other harder objects.

[0072] The present disclosure sets an elastic piece 4 between the shell wall where the explosion-proof valve 2 is located and the bare cell 3 to buffer the bare cell 3, thereby relieving the short-circuiting of the bare cell 3.

[0073] The scheme of the embodiments of the present disclosure can be applied to, but not limited to, a battery pack including a battery monomer or a battery unit, and can also be applied to a power consumption device including a battery monomer and a battery pack.

[0074] The present disclosure provides a power consumption device, which comprises a device main body and a battery pack, and the battery pack is used to supply power to the device main body.

[0075] The power consuming device is a device that uses electric energy as a power source to realize corresponding functions by consuming electric energy. Exemplarily, the power consuming device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric automobile, a ship, a spacecraft, etc. Among them, the electric toy can include fixed or mobile electric toys, such as game consoles, electric automobile toys, electric ship toys, and electric aircraft toys, etc., and the spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc.

[0076] The device body refers to the main structure that consumes electric energy to realize corresponding functions. For example, the power consuming device can be a mobile phone, and the device body is the part that can realize functions such as communication, which is powered by the battery monomer or the battery pack to the part that can realize functions such as communication. For example, the power consuming device can be a car, and the device body is the part that can provide people with seats and can drive on the road, which is powered by the battery monomer or the battery pack to the part that can provide people with seats and can drive on the road.

[0077] The battery pack refers to a device that can output electric energy. Exemplarily, the battery pack can output electric energy through the battery monomer. Exemplarily, the battery pack can output electric energy through the battery module composed of the battery monomer.

[0078] Taking the power consuming device of an embodiment of the present disclosure as a vehicle as an example for description.

[0079] The vehicle provided by an embodiment of the present disclosure can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile, or a range extended automobile, etc. The vehicle is internally provided with a battery pack, which can be arranged at the bottom, the head, or the tail of the vehicle. The battery pack can be used for power supply of the vehicle, for example, the battery pack can be used as the operating power supply of the vehicle. The vehicle can further include a controller and a motor, and the controller can be used to control the battery pack to supply power to the motor. For example, the battery pack can be used for the working power demand of the vehicle during starting, navigation, and driving.

[0080] In some embodiments of the present disclosure, the battery pack can not only be used as the operating power supply of the vehicle, but also be used as the driving power supply of the vehicle, to replace or partially replace fuel or natural gas to provide driving power for the vehicle.

[0081] The present disclosure further provides a battery pack, which includes a box body and a battery monomer, and the battery monomer is arranged in the interior of the box body.

[0082] The battery unit includes at least two battery cells and one or at least two pucks. The pucks are electrically connected to two different battery cells respectively. The number of battery cells can be multiple, and the multiple battery cells can be connected in series, in parallel, or in a mixed connection. The mixed connection means that the multiple battery cells are connected in series and in parallel. The multiple battery cells can be directly connected in series, in parallel, or in a mixed connection, and the whole of the multiple battery cells is placed in the box. Of course, the multiple battery cells can be connected in series, in parallel, or in a mixed connection to form a battery module, and the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and the whole of the multiple battery modules connected in series, in parallel, or in a mixed connection is placed in the box. The battery pack can also include other structures, for example, the battery pack can also include a busbar component for realizing the electrical connection between the multiple battery cells.

[0083] The energy storage device includes a mounting container and a battery pack, and the battery pack is arranged in the mounting container.

[0084] The battery cell includes an outer shell 1, an explosion-proof valve 2, a bare cell 3, and an elastic member 4. The explosion-proof valve 2 is arranged in the outer shell 1, the bare cell 3 is arranged in the outer shell 1, and the arrangement direction of the explosion-proof valve 2 and the bare cell 3 is a first direction 3a. The elastic member 4 is located between the bare cell 3 and the shell wall of the outer shell 1 on the side of the outer shell 1 along the first direction 3a towards the explosion-proof valve 2.

[0085] The battery cell refers to a unit capable of realizing mutual conversion between chemical energy and electrical energy.

[0086] In the embodiments of the present disclosure, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0087] In the embodiments of the present disclosure, the battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead-acid battery, etc., and the embodiments of the present disclosure are not limited thereto.

[0088] The battery cell can be a square winding cell or a laminated cell.

[0089] The explosion-proof valve 2 refers to a component for preventing the battery cell from exploding under abnormal conditions. The valve of the explosion-proof valve 2 can be kept closed under a certain pressure, and the valve is opened when the internal pressure of the battery cell reaches a certain degree, so as to release the gas.

[0090] Exemplarily, the shell 1 comprises a shell body 11 and a top cover 10, the top cover 10 is arranged on the shell body 11, the explosion-proof valve 2 is arranged on the top cover 10, and the bare battery cell 3 is arranged inside the shell body 11.

[0091] Exemplarily, the first direction 3a is arranged along the length direction of the bare battery cell 3.

[0092] Exemplarily, the first direction 3a is arranged perpendicularly to the thickness direction of the bare battery cell 3.

[0093] In the scheme of the embodiment of the present disclosure, the elastic member 4 is arranged between the bare battery cell 3 and the shell wall of the shell 1 on the side along the first direction 3a towards the explosion-proof valve 2. When thermal runaway occurs inside the battery monomer, the bare battery cell 3 will be driven by the airflow, and thus will move towards the explosion-proof valve 2 along the first direction 3a. The elastic member 4 can buffer the bare battery cell 3 to a certain extent, reduce the rigid impact received by the bare battery cell 3, and thus relieve the situation that the bare battery cell 3 is deformed due to external load to cause short circuit.

[0094] In an embodiment, referring to FIG. 2, the battery monomer further comprises an insulating member 5, the insulating member 5 is arranged between the bare battery cell 3 and the shell wall of the shell 1 on the side along the first direction 3a towards the explosion-proof valve 2, and the elastic member 4 is at least partially arranged on the side of the insulating member 5 along the first direction 3a towards the bare battery cell 3.

[0095] The insulating member 5 refers to a component made of insulating material and arranged between the bare battery cell 3 and the shell wall where the pole is located, and is used to relieve the short circuit between the bare battery cell 3 and the shell wall.

[0096] In the scheme of the embodiment of the present disclosure, the battery monomer further comprises an insulating member 5, the insulating member 5 is arranged between the bare battery cell 3 and the shell wall of the shell 1 on the side along the first direction 3a towards the explosion-proof valve 2. The insulating member 5 can relieve the short circuit between the bare battery cell 3 and the shell body 11, and can reduce the rigid collision between the bare battery cell 3 and the shell body 11 to a certain extent, and thus further reduce the short circuit of the bare battery cell 3.

[0097] Exemplarily, the bare battery cell 3 is a laminated battery cell or a square wound battery cell.

[0098] Exemplarily, the bare battery cell 3 comprises a positive electrode sheet, a negative electrode sheet and a separator, and the separator is arranged between the positive electrode sheet and the negative electrode sheet.

[0099] In an embodiment, referring to FIG. 2, the insulating member 5 is formed with a first protrusion 5a, the first protrusion 5a protrudes towards the bare battery cell 3 along the first direction 3a, and the elastic member 4 is connected to the side of the first protrusion 5a along the first direction 3a towards the bare battery cell 3.

[0100] Exemplarily, the elastic member 4 is bonded with the first protrusion 5a.

[0101] Exemplarily, the projection area of the elastic member 4 overlaps with the projection area of the first protrusion 5a in the projection along the first direction 3a.

[0102] Exemplarily, the number of the first protrusions 5a is multiple, and the multiple first protrusions 5a are arranged at intervals.

[0103] Exemplarily, the shape of the first protrusion 5a is a rectangular block.

[0104] In the scheme of the embodiment of the present disclosure, the insulating member 5 is formed with the first protrusion 5a, and the first protrusion 5a protrudes towards the bare battery cell 3 along the first direction 3a. The first protrusion 5a can increase the size of the insulating member 5 along the first direction 3a, and the insulating member 5 can abut against the bare battery cell 3 through the first protrusion 5a, thereby pressing the bare battery cell 3, so as to reduce the situation that the bare battery cell 3 moves along the first direction 3a during the working process of the battery monomer.

[0105] It can be understood that the embodiment of the present disclosure is not limited to that the insulating member 5 is formed with the first protrusion 5a. Exemplarily, the insulating member 5 is a plate structure.

[0106] In an embodiment, referring to FIG. 3, the first protrusion 5a is formed with a avoiding cavity 5b, the tab of the bare battery cell 3 is located in the avoiding cavity 5b, the first protrusion 5a is arranged around the circumference of the tab, the elastic member 4 is annular, and the elastic member 4 is arranged around the tab.

[0107] In the scheme of the embodiment of the present disclosure, the first protrusion 5a is formed with the avoiding cavity 5b, the tab of the bare battery cell 3 is located in the avoiding cavity 5b, and the elastic member 4 is annular and arranged around the tab. The first protrusion 5a is formed with the avoiding cavity 5b to avoid the tab of the bare battery cell 3, so as to reduce the situation that the tab is pressed by the insulating member 5. The elastic member 4 arranged around the tab can make full use of the space around the tab, and increase the contact area between the elastic member 4 and the bare battery cell 3 as much as possible, so as to increase the buffering effect of the elastic member 4, and further reduce the situation that the bare battery cell 3 is short-circuited.

[0108] It can be understood that the embodiment of the present disclosure is not limited to that the elastic member 4 is arranged around the tab. Exemplarily, the elastic member 4 is located on both sides of the tab along the width direction or the thickness direction of the bare battery cell 3. The width direction of the bare battery cell 3 is arranged perpendicularly to the thickness direction of the bare battery cell 3 and the first direction 3a, respectively. The thickness direction of the bare battery cell 3 is arranged perpendicularly to the width direction of the bare battery cell 3 and the first direction 3a, respectively.

[0109] In an embodiment, referring to FIG. 4, the number of the elastic members 4 is two, and the two elastic members 4 are located on both sides of the insulating member 5 along the second direction 4a, respectively. The second direction 4a is arranged perpendicularly to the first direction 3a.

[0110] Exemplarily, the second direction 4a is arranged along the width direction of the bare battery cell 3.

[0111] Exemplarily, the second direction 4a is arranged perpendicularly to the first direction 3a.

[0112] Exemplarily, the two tabs of the bare battery cell 3 are arranged along the width direction of the bare battery cell 3.

[0113] In the embodiment of the present disclosure, the number of the elastic member 4 is two, and the two elastic members 4 are respectively located on the two sides of the insulating member 5. The elastic members 4 are arranged at intervals, which can balance the blocking effect of the elastic members 4 on the bare battery cell 3, so that the stress of the bare battery cell 3 is more uniform.

[0114] It can be understood that the embodiment of the present disclosure is not limited to the number of the elastic member 4 being two, and the two elastic members 4 being respectively located on the two sides of the insulating member 5 along the second direction 4a. Exemplarily, the number of the elastic member 4 is single, and the elastic member 4 is located on one side of the insulating member 5 along the second direction 4a.

[0115] In an embodiment, referring to FIG. 5, the side of the elastic member 4 facing the insulating member 5 is formed with a mounting groove 4b, the opening of the mounting groove 4b faces the insulating member 5, and the insulating member 5 is partially located in the mounting groove 4b.

[0116] Exemplarily, the mounting groove 4b is a square groove.

[0117] Exemplarily, the insulating member 5 is clamped in the mounting groove 4b, and the insulating member 5 is connected with the elastic member 4 through interference fit.

[0118] In the embodiment of the present disclosure, the side of the elastic member 4 facing the insulating member 5 is formed with a mounting groove 4b, and the opening of the mounting groove 4b faces the insulating member 5. The insulating member 5 can be connected with the elastic member 4 through the mounting groove 4b, so that the insulating member 5 and the elastic member 4 are connected as a whole, which can to some extent alleviate the situation that the elastic member 4 shakes inside the battery monomer, and the elastic member 4 can more stably buffer the bare battery cell 3 during the working process.

[0119] It can be understood that the embodiment of the present disclosure is not limited to the insulating member 5 being partially located in the mounting groove 4b. Exemplarily, the elastic member 4 is separated from the insulating member 5, and the elastic member 4 can move relative to the insulating member 5 inside the battery monomer.

[0120] In an embodiment, along the arrangement direction of the explosion-proof valve 2 and the bare battery cell 3, the size of the elastic member 4 is a target size, the range of the target size is 0.5mm-5.0mm, the contact area of the elastic member 4 with the bare battery cell 3 is a first area, the arrangement direction of the explosion-proof valve 2 and the bare battery cell 3 is projected, the area of the projection area of the bare battery cell 3 is a second area, the units of the first area and the second area are the same, the ratio of the first area to the second area is a first ratio, and the range of the first ratio is 5.1%-44.7%.

[0121] Exemplarily, the target size is 0.5 mm, 1.0 mm, 2.0 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm or 5.0 mm.

[0122] It can be understood that the size of the target size can be measured by a ruler or a vernier caliper at room temperature and normal pressure before the first charging of the battery monomer.

[0123] Exemplarily, the first ratio can be 5.1%, 10.0%, 15.0%, 20.0%, 30.0%, 35.0%, 40.0%, 44.0% or 44.7%.

[0124] mm refers to millimeter in the unit of length.

[0125] In the embodiments of the present disclosure, the target size and the first ratio are within a suitable range, which can make the elastic member 4 as small as possible while providing a certain buffering effect, thereby increasing the size of the bare cell 3 in the length direction and increasing the energy density of the battery monomer.

[0126] Exemplarily, the target size is D, the first area is A, and the second area is B, and D and the ratio A / B have the following relationship:

[0127] Exemplarily, the size D is shown in FIG. 8.

[0128] It can be understood that the ratio between the first area and the second area is the first ratio, and the thicker the thickness of the elastic member 4, the better the buffering effect of the elastic member 4 in preventing the bare cell 3 from moving upward after the explosion-proof valve 2 is opened, and the better the protection effect on the bare cell 3. The larger the first ratio, the larger the effective area of the elastic member 4, the better the stress concentration condition is relieved, and the better the buffering effect of the elastic member 4. Therefore, when the thickness of the elastic member 4 takes a maximum value, the first ratio has a minimum value, so that the elastic member 4 has a certain pressure contact area to relieve the short circuit of the bare cell 3. Therefore, the ratio of the thickness of the elastic member 4 to the first ratio has a maximum value. Conversely, when the first ratio has a maximum value due to the limitation of the internal space of the battery monomer, the thickness of the elastic member 4 has a minimum value, so that the elastic member 4 has a certain buffering capacity to relieve the short circuit of the bare cell 3. That is, the ratio of the thickness of the elastic member 4 to the first ratio has a minimum value. The present discloser obtains the following test data by adjusting the thickness of the elastic member 4 and the first ratio.

[0129] In an embodiment, along the arrangement direction of the explosion-proof valve 2 and the bare cell 3, the size of the elastic member 4 is the target size, the range of the target size is 0.5 mm-5.0 mm, and the opening pressure of the explosion-proof valve 2 is the target pressure, and the range of the target pressure is 0.5 MPa-5.5 MPa.

[0130] Exemplarily, the target pressure is 0.5 MPa, 1.0 MPa, 1.5 MPa, 2.0 MPa, 3.0 MPa, 4.0 MPa, 4.5 MPa, 5.0 MPa or 5.5 MPa.

[0131] MPa refers to a pressure unit of megapascal.

[0132] It can be understood that the target pressure can be obtained by measuring the sealed container provided with the explosion-proof valve 2 through a pressure gauge, and continuously inflating the sealed container until the explosion-proof valve 2 is opened, and the opening pressure of the explosion-proof valve 2 is the target pressure.

[0133] In the embodiment of the present disclosure, the size of the target pressure can control the load of the bare cell 3 when the bare cell 3 rushes to the explosion-proof valve 2 in the case of thermal runaway. The target pressure in the appropriate range can enable the elastic member 4 to stably buffer the bare cell 3, and further, alleviate the case that the explosion-proof valve 2 is opened by the gas generated by the bare cell 3 in the normal working condition.

[0134] Exemplarily, the target size is D, and the opening pressure of the explosion-proof valve 2 is P, the unit of P is MPa, and there is a relationship as follows:

[0135] 0.25≤D×P≤8.50

[0136] It can be understood that the greater the thickness of the elastic member 4, the greater the buffering effect of the elastic member 4 on the bare cell 3. The higher the opening pressure of the explosion-proof valve 2, the stronger the impact load caused by the upward rush of the bare cell 3 at the moment of opening, and the more serious the damage to the bare cell 3. When the thickness of the elastic member 4 is maximized due to the idling of the internal space of the bare cell 3, the opening pressure has a maximum value, so as to alleviate the short circuit of the bare cell 3 due to the larger load. Therefore, the product of D and P has a maximum value. When the opening pressure has a minimum value due to the demand of gas generation of the bare cell 3 in the normal working state, the thickness of the elastic member 4 has a minimum value, so that the elastic member 4 can provide a certain buffering effect. Therefore, the product of D and P has a minimum value. The present discloser obtains the following test data by adjusting the thickness of the elastic member 4 and the first ratio.

[0137] In an embodiment, the elastic modulus of the elastic member is greater than or equal to 0.1 MPa and less than or equal to 1000 MPa.

[0138] Exemplarily, the elastic modulus of the elastic member 4 is 0.1 MPa, 0.5 MPa, 1.0 MPa, 10 MPa, 50 MPa, 100 MPa, 200 MPa, 300 MPa, 800 MPa, 900 MPa or 1000 MPa.

[0139] In the embodiments of the present disclosure, the elastic modulus of the elastic member 4 is in a suitable range, so that the deformation of the elastic member 4 is as small as possible in the case of buffering the bare battery cell 3, thereby reducing the size of the elastic member 4 along the first direction 3a, and reducing the size of the battery monomer along the first direction 3a.

[0140] In an embodiment, the elastic modulus of the elastic member is greater than or equal to 0.5 MPa and less than or equal to 100 MPa.

[0141] In the embodiments of the present disclosure, the elastic modulus of the elastic member 4 is in a smaller range, which can further increase the buffering effect of the elastic member 4 on the bare battery cell 3, and can control the deformation of the elastic member 4 in a suitable range.

[0142] In an embodiment, referring to FIGS. 6-8, the shell 1 includes a top cover 10 and a shell body 11 connected to each other, the top cover 10 covers the shell body 11, the explosion-proof valve 2 is arranged on the top cover 10, one of the elastic member 4 and the top cover 10 is formed with a second protrusion 4c, and the other is formed with a positioning groove 10a, and the second protrusion 4c is at least partially located in the positioning groove 10a to install the elastic member 4.

[0143] For example, the second protrusion 4c is formed on the elastic member 4, and the positioning groove 10a is formed on the top cover 10.

[0144] For example, the number of the second protrusions 4c is multiple, and the multiple second protrusions 4c are arranged at intervals along the second direction 4a.

[0145] In the embodiments of the present disclosure, the second protrusion 4c and the positioning groove 10a are formed between the top cover 10 and the elastic member 4, which can cooperate with each other. The cooperation between the second protrusion 4c and the positioning groove 10a can quickly install the elastic member 4, and can limit the elastic member 4 to a certain extent, and alleviate the shaking of the elastic member 4 inside the battery monomer.

[0146] It can be understood that the embodiments of the present disclosure are not limited to the installation of the elastic member 4 on the top cover 10 through the second protrusion 4c and the positioning groove 10a. For example, the elastic member 4 is bonded to the top cover 10.

[0147] In an embodiment, the material of the elastic member 4 is an insulating material.

[0148] For example, the material of the elastic member 4 is a rubber material, a silica gel material, or an elastic polyurethane material.

[0149] In the embodiments of the present disclosure, the material of the elastic member 4 is an insulating material, which can reduce the short circuit of the battery monomer during use. The elastic member 4 can replace the insulating member 5 to alleviate the short circuit between the bare battery cell 3 and the shell body 11, thereby reducing the number of components inside the battery monomer.

[0150] In an embodiment, the elastic member 4 comprises an elastic member body and a protective layer connected to each other, the protective layer covers the elastic member body, and the protective layer comprises an insulating layer and / or a corrosion-resistant layer, the corrosion-resistant layer is used to inhibit corrosion of the elastic member body by electrolyte.

[0151] For example, the corrosion-resistant layer is made of soft polyvinyl chloride, polytetrafluoroethylene or polyurethane.

[0152] In the embodiment of the present disclosure, the elastic member 4 has a multi-layer structure, and the protective layer can alleviate the situation that the bare battery cell 3 directly contacts the external metal to cause short circuit or the situation that the elastic member 4 is corroded by electrolyte.

[0153] In an embodiment, referring to FIGS. 1 to 4, the battery monomer comprises a shell 1, a burst valve 2, a bare battery cell 3 and an elastic member 4. The burst valve 2 is arranged in the shell 1, the bare battery cell 3 is arranged in the shell 1, and the arrangement direction of the burst valve 2 and the bare battery cell 3 is a first direction 3a. The elastic member 4 is located between the bare battery cell 3 and the shell wall of the shell 1 on the side of the shell 1 along the first direction 3a towards the burst valve 2. The battery monomer further comprises an insulating member 5 located between the bare battery cell 3 and the shell wall of the shell 1 on the side of the shell 1 along the first direction 3a towards the burst valve 2, and the elastic member 4 is at least partially located on the side of the insulating member 5 along the first direction 3a towards the bare battery cell 3. The insulating member 5 is formed with a first protrusion 5a protruding towards the bare battery cell 3 along the first direction 3a, and the elastic member 4 is connected to the side of the first protrusion 5a along the first direction 3a towards the bare battery cell 3. The number of the elastic member 4 is two, and the two elastic members 4 are respectively located on the two sides of the insulating member 5 along a second direction 4a, and the second direction 4a is arranged transversely to the first direction 3a. The side of the elastic member 4 towards the insulating member 5 is formed with a mounting groove 4b, the opening of the mounting groove 4b faces the insulating member 5, and the insulating member 5 is partially located in the mounting groove 4b. The elastic modulus of the elastic member 4 is greater than or equal to 0.5 MPa and less than or equal to 100 MPa. The elastic member 4 comprises an elastic member body and a protective layer connected to each other, the protective layer covers the elastic member body, and the protective layer comprises an insulating layer and / or a corrosion-resistant layer, the corrosion-resistant layer is used to inhibit corrosion of the elastic member body by electrolyte.

[0154] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than limit them; although the present disclosure is described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can be modified, or some or all of the technical features can be replaced equivalently; 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 disclosure, and they should be covered in the scope of the claims and the specification of the present disclosure. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present disclosure is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, comprising: a housing; an explosion-proof valve arranged in the housing; a bare cell arranged in the housing, the arrangement direction of the explosion-proof valve and the bare cell being a first direction; a resilient member arranged between the bare cell and a housing wall on a side of the housing wall facing the explosion-proof valve along the first direction.

2. The battery cell of claim 1, wherein, The battery cell further comprises an insulating member arranged between the bare cell and a housing wall on a side of the housing wall facing the explosion-proof valve along the first direction, and the resilient member is at least partially arranged on a side of the insulating member facing the bare cell along the first direction.

3. The battery cell of claim 2, wherein, The insulating member is formed with a first protrusion protruding toward the bare cell along the first direction, and the resilient member is connected to a side of the first protrusion facing the bare cell.

4. The battery cell of claim 3, wherein, The first protrusion is formed with a relief cavity in which a tab of the bare cell is arranged, and the first protrusion is arranged around the tab in a circumferential direction, and the resilient member is annular and arranged around the tab.

5. The battery cell according to any one of claims 2 to 4, wherein, The number of the resilient members is two, and the two resilient members are arranged on two sides of the insulating member along a second direction intersecting the first direction.

6. The battery cell of claim 5, wherein, A side of the resilient member facing the insulating member is formed with a mounting groove, and an opening of the mounting groove faces the insulating member, and the insulating member is partially arranged in the mounting groove.

7. The battery cell according to any one of claims 1 to 6, wherein, Along the arrangement direction of the explosion-proof valve and the bare cell, the size of the resilient member is a target size in a range of 0.5mm to 5.0mm, the contact area of the resilient member and the bare cell is a first area, the arrangement direction of the explosion-proof valve and the bare cell is projected, the area of a projection region of the bare cell is a second area, the units of the first area and the second area are the same, the ratio of the first area to the second area is a first ratio, and the first ratio is in a range of 5.1% to 44.7%.

8. The battery cell according to any one of claims 1 to 7, wherein, Along the arrangement direction of the explosion-proof valve and the bare cell, the size of the resilient member is a target size in a range of 0.5mm to 5.0mm, and the opening pressure of the explosion-proof valve is a target pressure in a range of 0.5MPa to 5.5MPa.

9. The battery cell according to any one of claims 1 to 8, wherein, The elastic modulus of the resilient member is greater than or equal to 0.1MPa and less than or equal to 1000MPa.

10. The battery cell of claim 9, wherein, The elastic modulus of the resilient member is greater than or equal to 0.5MPa and less than or equal to 100MPa.

11. The battery cell according to any one of claims 1 to 10, wherein, The housing comprises a top cover and a housing body connected to each other, the top cover covers the housing body, the explosion-proof valve is arranged in the top cover, one of the resilient member and the top cover is formed with a second protrusion, and the other is formed with a positioning groove, and the second protrusion is at least partially arranged in the positioning groove to mount the resilient member.

12. The battery cell according to any one of claims 1 to 11, wherein, The material of the resilient member is an insulating material.

13. The battery cell according to any one of claims 1 to 12, wherein, The resilient member comprises a resilient member body and a protective layer connected to each other, the protective layer covers the resilient member body, the protective layer comprises an insulating layer and / or a corrosion-resistant layer, and the corrosion-resistant layer is used to inhibit corrosion of the resilient member body by electrolyte. 14.A battery pack, comprising: a box body; At least one battery cell according to any one of claims 1 to 13 is arranged inside the box.

15. An electric device comprising: a device body; a battery pack according to claim 14 for supplying power to the device body.

16. An energy storage device comprising: a mounting container; a battery pack according to claim 14 arranged inside the mounting container.

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