Battery monomer, battery device and electric device

Abstract

The utility model provides a battery monomer, a battery device and a power utilization device, a shell in the battery monomer comprises a wall part, an electrode terminal assembly is arranged on the wall part, and the electrode terminal assembly comprises a first electrode terminal and a second electrode terminal which are opposite in polarity; the negative temperature coefficient thermistor is configured to electrically connect the first electrode terminal and the second electrode terminal in a state that the received temperature exceeds a first threshold value; the adapter connects the electrode assembly and the electrode terminal assembly. When the temperature of the single battery exceeds a first threshold value, the first electrode terminal and the second electrode terminal are electrically connected and conducted, an internal loop of the single battery is short-circuited, large current flows through the fusing structure in the adapter to increase the temperature of the fusing structure, and when the temperature of the fusing structure exceeds a second threshold value, the connection between the electrode assembly and the electrode terminal assembly is cut off. The internal circuit break of the battery monomer is realized, the heat production possibility of the battery monomer is reduced, the possibility of thermal runaway of the battery monomer is reduced, and the reliability of the battery monomer is improved.

Description

TECHNICAL FIELD

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

[0002] The battery device has the advantages of high specific energy and high power density, and is widely used in electronic devices and vehicles, such as mobile phones, notebook computers, electric vehicles, electric cars, electric planes, electric ships and electric tools.

[0003] With the continuous expansion of the application range of the battery device, people's requirements for the reliability of the battery device are also getting higher and higher. How to reduce the possibility of thermal runaway of the battery monomer and improve the reliability of the battery monomer is more and more concerned by the technical personnel in the field. UTILITY MODEL CONTENT

[0004] In view of the above problems, the present application provides a battery monomer, a battery device and a power utilization device, which can reduce the possibility of thermal runaway and has good reliability.

[0005] In a first aspect, some embodiments of the present application provide a battery monomer, which comprises a shell, an electrode terminal assembly, an electrode assembly, a negative temperature coefficient thermistor and an adapter, the shell comprises a wall portion, the electrode terminal assembly is arranged on the wall portion, the electrode terminal assembly comprises first and second electrode terminals with opposite polarities; the electrode assembly is accommodated in the shell; the negative temperature coefficient thermistor is configured to electrically connect the first and second electrode terminals when the temperature received by the negative temperature coefficient thermistor exceeds a first threshold value; the adapter is accommodated in the shell and connects the electrode assembly and the electrode terminal assembly, and the adapter is provided with a fuse structure configured to cut off the connection between the electrode assembly and the electrode terminal assembly when the temperature received by the fuse structure exceeds a second threshold value, the second threshold value being greater than the first threshold value.

[0006] In the above structure, when the temperature of the battery monomer exceeds the first threshold value, the first and second electrode terminals are electrically connected and conductive, the internal circuit of the battery monomer is short-circuited, a large current flows through the fuse structure in the adapter, the temperature of the fuse structure rises, and when the temperature received by the fuse structure exceeds the second threshold value, the connection between the electrode assembly and the electrode terminal assembly is cut off, the internal circuit of the battery monomer is broken, the possibility of heat generation of the battery monomer is reduced, which is conducive to reducing the possibility of thermal runaway of the battery monomer and improving the reliability of the battery monomer. In addition, since the negative temperature coefficient thermistor does not accompany mechanical action when the first and second electrode terminals are conductive, the contact area of the internal circuit of the battery monomer remains stable and is not easy to cause sparking, so that the battery monomer can be short-circuited in time when the temperature exceeds the first threshold value.

[0007] According to the battery cell provided by some embodiments of the present application, the first electrode terminal is electrically connected to the wall portion through a negative temperature coefficient thermistor, and the second electrode terminal is electrically connected to the wall portion, so that the on-off of the negative temperature coefficient thermistor between the first electrode terminal and the wall portion can control whether the first electrode terminal and the second electrode terminal are in communication.

[0008] According to the battery cell provided by some embodiments of the present application, the first electrode terminal is electrically connected to the wall portion through a negative temperature coefficient thermistor, and the second electrode terminal is electrically connected to the wall portion through a negative temperature coefficient thermistor, so that the on-off of the first electrode terminal and the second electrode terminal is controlled by two negative temperature coefficient thermistors in series.

[0009] According to the battery cell provided by some embodiments of the present application, the wall portion is provided with an electrode lead-out hole, the first electrode terminal comprises a terminal body and a terminal plate connected to each other, the terminal plate is located on the outer side of the wall portion away from the electrode assembly, the terminal body is arranged in the electrode lead-out hole and connected to the adapter, and the terminal plate can jointly act on part of the structure of the terminal body to clamp the wall portion from both the inner and outer sides of the wall portion.

[0010] According to the battery cell provided by some embodiments of the present application, the negative temperature coefficient thermistor is clamped between the terminal plate and the wall portion, so that the negative temperature coefficient thermistor can stably contact the terminal plate and the wall portion, and when the negative temperature coefficient thermistor is turned on, the negative temperature coefficient thermistor and the terminal plate have a small contact resistance.

[0011] According to the battery cell provided by some embodiments of the present application, a first conductive adhesive structure is arranged between the negative temperature coefficient thermistor and the terminal plate, and a second conductive adhesive structure is arranged between the negative temperature coefficient thermistor and the wall portion, so that after the negative temperature coefficient thermistor is turned on, the negative temperature coefficient thermistor can be stably electrically connected to the terminal plate and the wall portion.

[0012] According to the battery cell provided by some embodiments of the present application, the outer surface of the wall portion away from the electrode assembly is recessed inward to form a recess, and at least part of the negative temperature coefficient thermistor is arranged in the recess, so that the recess can fix the negative temperature coefficient thermistor and reduce the possibility of position displacement of the negative temperature coefficient thermistor.

[0013] According to the battery cell provided by some embodiments of the present application, the terminal body comprises a large-diameter section and a small-diameter section connected to each other along the thickness direction of the wall portion, the large-diameter section and the small-diameter section form a step, and the step face of the step is flush with the plane where the wall portion and the negative temperature coefficient thermistor abut. By making the step face flush with the plane where the wall portion and the negative temperature coefficient thermistor abut, when the negative temperature coefficient thermistor is clamped between the terminal plate and the wall portion, the negative temperature coefficient thermistor also abuts the step face at the same time, which increases the contact area of the negative temperature coefficient thermistor and the terminal body, and is beneficial to reducing the contact resistance between the negative temperature coefficient thermistor and the terminal body.

[0014] According to the battery cell provided by some embodiments of the present application, the terminal body comprises a main body portion and a protruding portion protruding from the outer periphery of the main body portion, the main body portion is connected to the terminal plate through the electrode lead-out hole, the protruding portion is located in the shell and covers the electrode lead-out hole, and the negative temperature coefficient thermistor is clamped between the protruding portion and the wall portion. By clamping the negative temperature coefficient thermistor between the protruding portion and the wall portion, the negative temperature coefficient thermistor is located in the shell, and the negative temperature coefficient thermistor can be protected by the shell.

[0015] According to the battery cell provided by some embodiments of the present application, the negative temperature coefficient thermistor is provided with a mounting hole, and the negative temperature coefficient thermistor is fitted on the terminal body through the mounting hole, so that the negative temperature coefficient thermistor can be connected with the first electrode terminal on the wall portion, and the negative temperature coefficient thermistor is convenient to install.

[0016] According to the battery cell provided by some embodiments of the present application, the negative temperature coefficient thermistor is provided with a threaded hole, and the negative temperature coefficient thermistor is connected to the outer periphery of the terminal body through the threaded hole, which improves the firmness of the connection between the negative temperature coefficient thermistor and the terminal body, and further improves the stability of the electrical connection between the wall portion and the first electrode terminal when the negative temperature coefficient thermistor is turned on, which is beneficial to reducing the contact resistance.

[0017] According to the battery cell provided by some embodiments of the present application, the terminal plate and the wall portion are riveted through the terminal body, so that the terminal plate and the wall portion can be firmly connected to firmly clamp the negative temperature coefficient thermistor.

[0018] According to the battery cell provided by some embodiments of the present application, the battery cell further comprises a first insulating member and a second insulating member, at least part of the first insulating member is arranged between the terminal plate and the wall portion, and at least part of the second insulating member is arranged in the electrode lead-out hole and clamped between the terminal body and the wall portion. The first insulating member is arranged at least partially between the terminal plate and the wall portion, so that the wall portion and the terminal plate can be insulated and separated when the negative temperature coefficient thermistor is in a non-conductive state. The second insulating member is arranged at least partially in the electrode lead-out hole and clamped between the terminal body and the wall portion, which not only can insulate and separate the wall portion and the terminal body when the negative temperature coefficient thermistor is in a non-conductive state, but also can seal the gap between the terminal body and the inner wall of the electrode lead-out hole, which is conducive to improving the sealing performance of the internal space of the battery cell.

[0019] In a second aspect, some embodiments of the present application provide a battery device, which comprises the battery cell provided by any of the technical solutions.

[0020] In a third aspect, some embodiments of the present application provide a power utilization device, which comprises the battery device provided by the technical solutions, and the battery device is used to provide electric energy.

[0021] The technical solutions provided by the embodiments of the present application at least have the following beneficial effects:

[0022] Some embodiments of the present application provide a battery cell, which comprises a housing, an electrode terminal assembly, an electrode assembly, a negative temperature coefficient thermistor and an adapter, the housing comprises a wall part, the electrode terminal assembly is arranged on the wall part, the electrode terminal assembly comprises a first electrode terminal and a second electrode terminal with opposite polarity; the electrode assembly is accommodated in the housing; the negative temperature coefficient thermistor is configured to electrically connect the first electrode terminal and the second electrode terminal when the temperature received by the battery cell exceeds a first threshold value; the adapter is accommodated in the housing, the adapter connects the electrode assembly and the electrode terminal assembly, and the adapter is provided with a fuse structure configured to cut off the connection between the electrode assembly and the electrode terminal assembly when the temperature received by the battery cell exceeds a second threshold value, the second threshold value is greater than the first threshold value. In the above structure, when the temperature of the battery cell exceeds the first threshold value, the first electrode terminal and the second electrode terminal are electrically connected in conduction, the internal circuit of the battery cell is short-circuited, a larger current flows through the fuse structure in the adapter, the temperature of the fuse structure rises, and when the temperature received by the fuse structure exceeds the second threshold value, the connection between the electrode assembly and the electrode terminal assembly is cut off, the internal circuit of the battery cell is broken, the possibility of heat generation of the battery cell is reduced, the possibility of thermal runaway of the battery cell is reduced, and the reliability of the battery cell is improved. In addition, since the negative temperature coefficient thermistor does not accompany mechanical action when the first electrode terminal and the second electrode terminal are connected in conduction, the contact area of the internal circuit of the battery cell remains stable and is not easy to cause sparking, so that when the temperature of the battery cell exceeds the first threshold value, the battery cell can be short-circuited in time. BRIEF DESCRIPTION OF DRAWINGS

[0023] 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 detailed description is made with reference to the accompanying drawings.

[0024] Figure 1 A schematic view of a vehicle provided by some embodiments of the present application;

[0025] Figure 2 A split view of a battery device provided by some embodiments of the present application;

[0026] Figure 3 A split view of a battery cell provided by some embodiments of the present application;

[0027] Figure 4 A structure schematic view of an adapter in a battery cell provided by some embodiments of the present application;

[0028] Figure 5 A front view of a wall part in a battery cell provided by some embodiments of the present application;

[0029] Figure 6 Fig. 1 is a perspective view of a vehicle according to an embodiment of the present application; Figure 5 Fig. 2 is a perspective view of a battery device according to an embodiment of the present application; Fig. 3 is a perspective view of a controller according to an embodiment of the present application;

[0030] Fig. 4 is a perspective view of a motor according to an embodiment of the present application; Figure 7 Fig. 5 is a perspective view of a box according to an embodiment of the present application; Fig. 6 is a perspective view of an electrode terminal assembly according to an embodiment of the present application;

[0031] Fig. 7 is a perspective view of an electrode assembly according to an embodiment of the present application; Figure 8 Fig. 8 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application; Fig. 9 is a perspective view of a relay according to an embodiment of the present application;

[0032] Fig. 10 is a perspective view of a relay according to an embodiment of the present application; Figure 9 Fig. 11 is a perspective view of a relay according to an embodiment of the present application; Fig. 12 is a perspective view of a relay according to an embodiment of the present application;

[0033] Fig. 13 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application; Figure 10 Fig. 14 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application; Fig. 15 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application;

[0034] Fig. 16 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application; Figure 11 Fig. 17 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application. Fig. 18 is a perspective view of a negative temperature coefficient thermistor according to an embodiment of the present application.

[0035] In the drawings: 1, vehicle; 2, battery device; 3, controller; 4, motor; 5, box; 5a, first box part; 5b, second box part; 5c, accommodation space; 7, battery cell; 8, shell; 81, wall part; 811, electrode lead-out hole; 812, recess; 9, electrode terminal assembly; 91, first electrode terminal; 911, terminal body; 9111, body part; 91111, large-diameter section; 91112, small-diameter section; 91113, step face; 9112, protruding part; 912, terminal plate; 92, second electrode terminal; 10, electrode assembly; 101, electrode body; 102, tab; 20, negative temperature coefficient thermistor; 201, first conductive glue structure; 202, second conductive glue structure; 203, mounting hole; 204, threaded hole; 30, relay; 301, fuse structure; 40, first insulating part; 50, second insulating part. DETAILED DESCRIPTION

[0036] The embodiments of the technical solutions of the present application 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 application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0037] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should be understood as the usual meaning understood by the skilled person in the field to which the embodiments of the present application belong.

[0038] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0039] In addition, the technical terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0040] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0041] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0042] At present, from the development of market situation, the application of battery device is more and more extensive. The battery device is not only applied to the energy storage power supply system of water power, fire power, wind power and solar power station, but also widely applied to the battery monomer of energy storage container or energy storage cabinet. With the continuous expansion of the application range of battery device, people's requirements for the reliability of battery device are also getting higher and higher.

[0043] The battery apparatus mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells connected in series, in parallel, or in a mixed connection through a busbar component.

[0044] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells.

[0045] The battery cell can be a secondary battery cell, which refers to a battery cell that can be activated by charging after the battery cell is discharged.

[0046] The battery cell can be a lithium ion battery cell, a sodium ion battery cell, a sodium lithium ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium sulfur battery cell, a magnesium ion battery cell, a nickel hydrogen battery cell, a nickel cadmium battery cell, a lead-acid battery cell, etc.

[0047] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of the battery cell, active ions (such as lithium ions) are inserted and extracted between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can prevent the positive and negative electrodes from short-circuiting, and at the same time allow the active ions to pass through.

[0048] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of winding and stacking.

[0049] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of other shapes, and the prismatic battery cell includes a square battery cell, a blade-shaped battery cell, a multi-prismatic battery cell, such as a hexagonal prismatic battery cell, etc.

[0050] As an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing a plurality of battery cells into an independent module. As an example, the battery module can be formed by bundling a plurality of battery cells with a cable tie.

[0051] In some embodiments, the battery apparatus can include one or more battery packs, and the battery pack can include one or more battery cell assemblies. As an example, the battery pack includes a box and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the box, for example, by a fixing manner. As another example, the battery apparatus includes a plurality of battery packs, and the plurality of battery packs can be connected in series, in parallel, and in a mixed connection.

[0052] As an example, the box can include a first box and a second box. The first box and the second box are fastened so that an inside of the box forms a closed space to accommodate the battery monomer assembly. The closed here means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0053] As an example, the box can include a top cover, a frame and a bottom plate. The top cover and the bottom plate are connected with the frame respectively, so that an inside of the box forms a closed space to accommodate the battery monomer assembly.

[0054] In some embodiments, the box can be part of the chassis structure of the vehicle. For example, part of the box can be at least part of the floor of the vehicle, or part of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0055] In some embodiments, the battery device can be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0056] The battery monomer generates heat during operation. Usually, the heat generated by the battery monomer is taken away by the heat exchange assembly, so that the temperature of the battery monomer is within a suitable range. However, when the battery monomer has a high temperature due to high temperature environment, mechanical abuse or electrical abuse, etc., the heat generated by the battery monomer during operation will increase the risk of thermal runaway of the battery monomer. In some cases, a thermal deformation metal sheet is provided in the battery monomer, which changes the internal circuit structure of the battery monomer at high temperature, causing the internal circuit of the battery monomer to short circuit, so that the jumper fuse structure in the circuit is fused due to high temperature, cutting off the internal circuit of the battery monomer and preventing the battery monomer from generating heat itself. However, when the thermal deformation metal sheet is deformed and connected to the internal circuit of the battery monomer, the contact area of the thermal deformation metal sheet is small, and the contact position is easy to cause sparking, causing ablation and melting at the contact position, which is not conducive to the connection of the thermal deformation metal sheet. The thermal deformation metal sheet cannot short-circuit the internal circuit of the battery monomer in time to make the jumper fuse, and cannot play the role of reducing the risk of thermal runaway.

[0057] To reduce the possibility of thermal runaway of the battery cell and improve the reliability of the battery cell, some embodiments of the present application provide a battery cell, which comprises a shell, an electrode terminal assembly, an electrode assembly, a negative temperature coefficient thermistor and an adapter, the shell comprises a wall portion, the electrode terminal assembly is arranged on the wall portion, the electrode terminal assembly comprises first and second electrode terminals with opposite polarities; the electrode assembly is accommodated in the shell; the negative temperature coefficient thermistor is configured to electrically connect the first and second electrode terminals when the temperature experienced by the negative temperature coefficient thermistor exceeds a first threshold value; the adapter is accommodated in the shell and connects the electrode assembly and the electrode terminal assembly, and the adapter is provided with a fuse structure configured to cut off the connection between the electrode assembly and the electrode terminal assembly when the temperature experienced by the fuse structure exceeds a second threshold value, the second threshold value being greater than the first threshold value. In the above structure, when the temperature of the battery cell exceeds the first threshold value, the first and second electrode terminals are electrically connected and conductive, the internal circuit of the battery cell is short-circuited, a large current flows through the fuse structure in the adapter, the temperature of the fuse structure rises, and when the temperature experienced by the fuse structure exceeds the second threshold value, the connection between the electrode assembly and the electrode terminal assembly is cut off, the internal circuit of the battery cell is broken, the possibility of heat generation of the battery cell is reduced, the possibility of thermal runaway of the battery cell is reduced, and the reliability of the battery cell is improved. In addition, since the negative temperature coefficient thermistor does not accompany mechanical action when the first and second electrode terminals are connected, the contact area of the internal circuit of the battery cell remains stable and is not easy to cause sparking, so that when the temperature of the battery cell exceeds the first threshold value, the battery cell can be short-circuited in time.

[0058] The battery cell described in the embodiments of the present application is suitable for a battery device and a power consumption device using the battery device.

[0059] The power consumption device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy and an electric tool, etc. The vehicle 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 spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, such as a game console, an electric automobile toy, an electric ship toy and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator and an electric planer, etc.

[0060] The following embodiments take a vehicle as an example for convenience of description.

[0061] Figure 1 The following embodiments take a vehicle as an example for convenience of description.

[0062] As shown in Figure 1 , the interior of the vehicle 1 is provided with a battery device 2, which can be arranged at the bottom or the head or the tail of the vehicle 1. The battery device 2 can be used for power supply of the vehicle 1, for example, the battery device 2 can be used as the operating power supply of the vehicle 1.

[0063] The vehicle 1 can also include a controller 3 and a motor 4, the controller 3 is used to control the battery device 2 to supply power to the motor 4, for example, for the power demand of the vehicle 1 during starting, navigation and driving.

[0064] In some embodiments of the present application, the battery device 2 can not only be used as the operating power supply of the vehicle 1, but also be used as the driving power supply of the vehicle 1, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1.

[0065] Figure 2 The split structure schematic diagram of the battery device 2 provided for some embodiments of the present application is shown. As shown in Figure 2 , the battery device 2 includes a box body 5 and a battery cell 7, the battery cell 7 is contained in the box body 5. The battery cell 7 can be the smallest unit constituting the battery.

[0066] The box body 5 is used to contain the battery cell 7, and the box body 5 can be of various structures. In some embodiments, the box body 5 can include a first box body part 5a and a second box body part 5b, the first box body part 5a and the second box body part 5b are mutually covered, and the first box body part 5a and the second box body part 5b jointly define a containing space 5c for containing the battery cell 7. The second box body part 5b can be a hollow structure with one end open, and the first box body part 5a is a plate-like structure, which is covered on the open side of the second box body part 5b to form the box body 5 with the containing space 5c; the first box body part 5a and the second box body part 5b can also be hollow structures with one side open, and the open side of the first box body part 5a is covered on the open side of the second box body part 5b to form the box body 5 with the containing space 5c. Of course, the first box body part 5a and the second box body part 5b can be of various shapes, such as cylinder, cuboid, etc.

[0067] In order to improve the sealing performance of the first box body part 5a and the second box body part 5b after being connected, a sealing member such as sealing glue, sealing ring, etc. can be arranged between the first box body part 5a and the second box body part 5b.

[0068] Suppose the first box body part 5a is covered on the top of the second box body part 5b, the first box body part 5a can also be called the upper box cover, and the second box body part 5b can also be called the lower box body 5.

[0069] In the battery device 2, the battery cell 7 can be one or multiple. If the battery cell 7 is multiple, the multiple battery cells 7 can be connected in series, in parallel, or in a mixed connection, where the mixed connection means that the multiple battery cells 7 are connected in series and in parallel. The multiple battery cells 7 can be directly connected in series, in parallel, or in a mixed connection, and the whole of the multiple battery cells 7 can be accommodated in the case 5. Alternatively, the multiple battery cells 7 can be connected in series, in parallel, or in a mixed connection to form battery modules, and the multiple battery modules can be connected in series, in parallel, or in a mixed connection to form a whole, which can be accommodated in the case 5.

[0070] Some embodiments of the present application provide a battery cell, referring to Figure 3 The battery cell 7 includes a housing 8, an electrode terminal assembly 9, an electrode assembly 10, a negative temperature coefficient thermistor 20, and an adapter 30. The housing 8 includes a wall portion 81, and the electrode terminal assembly 9 is disposed on the wall portion 81. The electrode terminal assembly 9 includes first and second electrode terminals 91 and 92 having opposite polarities. The electrode assembly 10 is accommodated in the housing 8. The negative temperature coefficient thermistor 20 is configured to electrically connect the first and second electrode terminals 91 and 92 when a temperature experienced by the battery cell 7 exceeds a first threshold value. The adapter 30 is accommodated in the housing 8 and connects the electrode assembly 10 and the electrode terminal assembly 9. Referring to Figure 4 The adapter 30 is provided with a fuse structure 301 configured to cut the connection between the electrode assembly 10 and the electrode terminal assembly 9 when a temperature experienced by the battery cell 7 exceeds a second threshold value. The second threshold value is greater than the first threshold value.

[0071] The housing 8 can be a component of the battery cell 7 for enclosing a sealed space, which is used to accommodate other components of the battery cell 7. The wall portion 81 is a partial wall structure of the housing 8, which is used to enclose a sealed space in the housing 8.

[0072] The electrode terminal assembly 9 can be a component of the battery cell 7 for connecting with an external power consuming device or a charging device, which enables the electrical energy of the external charging device to be charged into the battery cell 7 or the electrical energy of the battery cell 7 to be provided to the external power consuming device. The first and second electrode terminals 91 and 92 are two terminal structures having opposite polarities, which are disposed on the wall portion 81 and can withstand a certain force, so that the first and second electrode terminals 91 and 92 can provide sufficient connection force to stably connect with the external power consuming device or the charging device.

[0073] The electrode assembly 10 is a component in which an electrochemical reaction occurs in the battery cell 7. One or more electrode assemblies 10 can be accommodated inside the case 8. The electrode assembly 10 can include an electrode body 101 and a tab 102, which are two main parts of the electrode assembly 10, the tab 102 extending from an end of the electrode body 101 facing the wall portion 81, the tab 102 being used to electrically connect with the electrode terminal, and the tab 102 being capable of leading current out of or into the electrode assembly 10. The electrode body 101 can include a positive electrode tab, a negative electrode tab, and a separator, the positive electrode tab and the negative electrode tab can be used as a positive electrode and a negative electrode, respectively, and active ions (e.g., lithium ions) are embedded in and extracted from between the positive electrode and the negative electrode during charging and discharging of the battery cell 7. The separator is arranged in a stack between the positive electrode tab and the negative electrode tab, and is used to isolate the positive electrode tab and the negative electrode tab, while preventing short circuit between the positive electrode and the negative electrode and allowing the active ions to pass through.

[0074] The adapter 30 can be a component inside the battery cell 7 for connecting the tab 102 with the electrode terminal assembly 9 to achieve electrical connection between the electrode assembly 10 and the electrode terminal assembly 9, so that current can flow between the electrode assembly 10 and the electrode terminal assembly 9.

[0075] The fuse structure 301 can be a structure provided on the adapter 30 for cutting off the electrical connection between the electrode assembly 10 and the electrode terminal assembly 9, and can cut off the electrical connection between the electrode assembly 10 and the electrode terminal assembly 9 in the event of overcurrent of the adapter 30.

[0076] By configuring the fuse structure 301 to cut off the electrical connection between the electrode assembly 10 and the electrode terminal assembly 9 in the event that the temperature received by the fuse structure 301 exceeds the second threshold value, the fuse structure 301 can be caused to melt and cut off the electrical connection between the electrode assembly 10 and the electrode terminal assembly 9 in the event of overcurrent of the adapter 30, thereby stopping the electrode assembly 10 from outputting electrical energy externally.

[0077] The second threshold value can be the melting point of the fuse structure 301, so that the fuse structure 301 can melt in the event that the temperature received by the fuse structure 301 exceeds the second threshold value.

[0078] For example, the melting point of the material at the fuse structure 301 can be configured as the second threshold value, so that the fuse structure 301 can melt in the event that the temperature received by the fuse structure 301 exceeds the second threshold value; or the fuse structure 301 can be thinned so that the thickness of the material at the fuse structure 301 is lower than the thickness of the material at other parts of the adapter 30, so that the melting temperature at the fuse structure 301 is lower than the temperature at other parts of the adapter 30, and the fuse structure 301 can melt in the event that the temperature received by the fuse structure 301 exceeds the second threshold value.

[0079] The negative temperature coefficient thermistor 20 is a sensor resistor whose resistance value decreases as the temperature increases. The negative temperature coefficient thermistor 20 is configured to electrically connect the first electrode terminal 91 and the second electrode terminal 92 in a state where the temperature received exceeds a first threshold value. The negative temperature coefficient thermistor 20 can be connected in a loop between the first electrode terminal 91 and the second electrode terminal 92. When the temperature received is less than or equal to the first threshold value, the resistance value of the negative temperature coefficient thermistor 20 is high, and the negative temperature coefficient thermistor 20 can cut off the loop between the first electrode terminal 91 and the second electrode terminal 92, so that the internal loop of the battery cell 7 is not short-circuited. When the temperature received exceeds the first threshold value, the resistance value of the negative temperature coefficient thermistor 20 decreases, and the negative temperature coefficient thermistor 20 can conduct the loop between the first electrode terminal 91 and the second electrode terminal 92, so that the current on the electrode assembly 10 can flow between the first electrode terminal 91 and the second electrode terminal 92 through the adapter 30, and the internal loop of the battery cell 7 is short-circuited.

[0080] The first threshold value can be set by a person skilled in the art according to actual conditions. When the temperature of the battery cell 7 reaches the first threshold value, the battery cell 7 does not have thermal runaway, but the temperature of the battery cell 7 in the normal working state does not reach the first threshold value. Exemplarily, the first threshold value can be set to a range of 80°C to 300°C, so that when the temperature of the battery cell 7 reaches the first threshold value, the battery cell 7 does not have thermal runaway, and the temperature of the battery cell 7 in the normal working state does not easily reach the first threshold value. In some embodiments, the first threshold value can be set to a range of 80°C to 110°C, and the first threshold value can be set by a person skilled in the art according to actual conditions.

[0081] In the above structure, when the temperature of the battery cell 7 exceeds the first threshold value, the first electrode terminal 91 and the second electrode terminal 92 are electrically connected and conducted, the internal loop of the battery cell 7 is short-circuited, a large current flows through the fuse structure 301 in the adapter 30, the temperature of the fuse structure 301 increases, and when the temperature received by the fuse structure 301 exceeds a second threshold value, the connection between the electrode assembly 10 and the electrode terminal assembly 9 is cut off, the internal loop of the battery cell 7 is broken, the possibility of heat generation of the battery cell 7 is reduced, the possibility of thermal runaway of the battery cell 7 is reduced, and the reliability of the battery cell 7 is improved. In addition, since the negative temperature coefficient thermistor 20 does not accompany mechanical action when the first electrode terminal 91 and the second electrode terminal 92 are conducted, the contact area of the internal loop of the battery cell 7 remains stable, and is not easy to cause sparking, so that when the temperature of the battery cell 7 exceeds the first threshold value, the battery cell 7 can be short-circuited in time.

[0082] In some embodiments, the first electrode terminal 91 is electrically connected to the wall portion 81 through the negative temperature coefficient thermistor 20, and the second electrode terminal 92 is electrically connected to the wall portion 81.

[0083] The first electrode terminal 91 is electrically connected to the wall portion 81 through the negative temperature coefficient thermistor 20, which can be that the first electrode terminal 91 is not directly connected to the wall portion 81, but the negative temperature coefficient thermistor 20 electrically connects the first electrode terminal 91 and the wall portion 81, so that the on-off of the negative temperature coefficient thermistor 20 can control whether the first electrode terminal 91 and the wall portion 81 are in communication. The second electrode terminal 92 is always electrically connected to the wall portion 81 and is in communication. This scheme makes the on-off of the negative temperature coefficient thermistor 20 between the first electrode terminal 91 and the wall portion 81 be able to control whether the first electrode terminal 91 and the second electrode terminal 92 are in communication.

[0084] In some embodiments, referring to Figure 5 and Figure 6 , the first electrode terminal 91 is electrically connected to the wall portion 81 through the negative temperature coefficient thermistor 20, and the second electrode terminal 92 is electrically connected to the wall portion 81 through the negative temperature coefficient thermistor 20.

[0085] The first electrode terminal 91 and the second electrode terminal 92 are both electrically connected to the wall portion 81 through the negative temperature coefficient thermistor 20, which can be that the first electrode terminal 91 and the second electrode terminal 92 are not directly connected to the wall portion 81, but the negative temperature coefficient thermistor 20 is provided with two, one negative temperature coefficient thermistor 20 electrically connects the first electrode terminal 91 and the wall portion 81, and the other negative temperature coefficient thermistor 20 electrically connects the second electrode terminal 92 and the wall portion 81, and the first electrode terminal 91, one negative temperature coefficient thermistor 20, the wall portion 81, the other negative temperature coefficient thermistor 20, and the second electrode terminal 92 are connected in series. This scheme makes the on-off of the first electrode terminal 91 and the second electrode terminal 92 be controlled by the two series-connected negative temperature coefficient thermistors 20.

[0086] Exemplarily, when the temperatures suffered by the two negative temperature coefficient thermistors 20 both exceed the first threshold value, the first electrode terminal 91 and the second electrode terminal 92 are in communication; when the temperature suffered by one of the two negative temperature coefficient thermistors 20 is less than or equal to the first threshold value, the first electrode terminal 91 and the second electrode terminal 92 are disconnected.

[0087] In some embodiments, the wall portion 81 is provided with an electrode leading hole 811, the first electrode terminal 91 comprises a terminal body 911 and a terminal plate 912 connected to each other, the terminal plate 912 is located on the outer side of the wall portion 81 away from the electrode assembly 10, and the terminal body 911 is arranged in the electrode leading hole 811 and connected to the adapter 30.

[0088] The electrode lead-out hole 811 can be a structure for setting the first electrode terminal 91, which is a through hole provided in the wall portion 81 in the thickness direction of the wall portion 81.

[0089] The terminal body 911 and the terminal plate 912 are two structural parts in the first electrode terminal 91, respectively, wherein the terminal body 911 is a part of the main body 9111 of the first electrode terminal 91, which is provided in the electrode lead-out hole 811, and the terminal plate 912 is a part of the first electrode terminal 91 located on the outer side of the wall portion 81 away from the electrode assembly 10, which is connected to the terminal body 911, and the terminal plate 912 can jointly act with part of the structure of the terminal body 911 to clamp the wall portion 81 from both the inner and outer sides of the wall portion 81.

[0090] The terminal body 911 is provided in the electrode lead-out hole 811 and connected to the adapter 30, which can be that the terminal body 911 passes through the electrode lead-out hole 811, and part of the structure of the terminal body 911 extends into the shell 8 to be connected to the adapter 30.

[0091] In some embodiments, the negative temperature coefficient thermistor 20 is clamped between the terminal plate 912 and the wall portion 81.

[0092] The negative temperature coefficient thermistor 20 is clamped between the terminal plate 912 and the wall portion 81, which can be that the negative temperature coefficient thermistor 20 is provided between the terminal plate 912 and the wall portion 81, and the negative temperature coefficient thermistor 20 is clamped by the terminal plate 912 and the wall portion 81, so that the negative temperature coefficient thermistor 20 can be stably in contact with the terminal plate 912 and the wall portion 81, so that when the negative temperature coefficient thermistor 20 is turned on, there is a small contact resistance between the negative temperature coefficient thermistor 20 and the terminal plate 912.

[0093] Exemplarily, the thickness of the negative temperature coefficient thermistor 20 in the thickness direction of the wall portion 81 is set to E, 0.1mm≤E≤1.5mm, not only making the negative temperature coefficient thermistor 20 have good structural strength and be stably clamped between the wall portion 81 and the terminal plate 912, but also making the thickness of the negative temperature coefficient thermistor 20 in the thickness direction of the wall portion 81 not easy to cause the size of the first electrode terminal 91 in the thickness direction of the wall portion 81 to be too large due to being too large.

[0094] In some embodiments, referring to Figure 7 , a first conductive glue structure 201 is provided between the negative temperature coefficient thermistor 20 and the terminal plate 912, and a second conductive glue structure 202 is provided between the negative temperature coefficient thermistor 20 and the wall portion 81.

[0095] The first conductive adhesive structure 201 can be an adhesive structure capable of conducting electricity. The first conductive adhesive structure 201 can be formed by curing an adhesive structure capable of conducting electricity coated on the surface of the negative temperature coefficient thermistor 20 facing the terminal plate 912. The first conductive adhesive structure 201 not only enables the terminal plate 912 and the negative temperature coefficient thermistor 20 to be firmly connected, but also enables the terminal plate 912 and the negative temperature coefficient thermistor 20 to be stably electrically connected after the negative temperature coefficient thermistor 20 is turned on.

[0096] The second conductive adhesive structure 202 can be an adhesive structure capable of conducting electricity. The second conductive adhesive structure 202 can be formed by curing an adhesive structure capable of conducting electricity coated on the surface of the negative temperature coefficient thermistor 20 facing the wall portion 81. The second conductive adhesive structure 202 not only enables the wall portion 81 and the negative temperature coefficient thermistor 20 to be firmly connected, but also enables the wall portion 81 and the negative temperature coefficient thermistor 20 to be stably electrically connected after the negative temperature coefficient thermistor 20 is turned on.

[0097] In some embodiments, with reference to Figure 6 and Figure 7 the outer surface of the wall portion 81 facing away from the electrode assembly 10 is recessed inward to form a recess 812, and at least part of the negative temperature coefficient thermistor 20 is arranged in the recess 812.

[0098] The recess 812 can be a structure formed on the wall portion 81 for fixing the negative temperature coefficient thermistor 20 and reducing the possibility of positional displacement of the negative temperature coefficient thermistor 20.

[0099] The recess 812 is formed by recessing the outer surface of the wall portion 81 facing away from the electrode assembly 10 inward, so that the negative temperature coefficient thermistor 20 positioned in the recess 812 can be arranged outside the wall portion 81.

[0100] At least part of the negative temperature coefficient thermistor 20 is arranged in the recess 812, which can be that part of the negative temperature coefficient thermistor 20 is located in the recess 812, and the other part of the negative temperature coefficient thermistor 20 extends out of the recess 812, so that the negative temperature coefficient thermistor 20 can be clamped by the wall portion 81 and the terminal plate 912; or the entire negative temperature coefficient thermistor 20 can be located in the recess 812, and the surface of the negative temperature coefficient thermistor 20 facing the terminal plate 912 is connected to the terminal plate 912 through the first conductive adhesive structure 201.

[0101] By arranging at least part of the negative temperature coefficient thermistor 20 in the recess 812, the negative temperature coefficient thermistor 20 can be limited by the recess 812, reducing the possibility of positional displacement of the negative temperature coefficient thermistor 20.

[0102] In some embodiments, with reference to Figure 8The terminal main body 911 includes a large-diameter section 91111 and a small-diameter section 91112 connected to each other along the thickness direction of the wall portion 81, the large-diameter section 91111 and the small-diameter section 91112 form a step, and a step face 91113 of the step is flush with a plane where the wall portion 81 and the negative temperature coefficient thermistor 20 abut, and the step face 91113 abuts against the negative temperature coefficient thermistor 20.

[0103] The large-diameter section 91111 and the small-diameter section 91112 are respectively two different parts connected to each other in the terminal main body 911, and the two parts are arranged along the thickness direction of the wall portion 81. The terminal plate 912 is connected to the small-diameter section 91112, so that the large-diameter section 91111 is farther away from the terminal plate 912 than the small-diameter section 91112, and the step face 91113 of the step is arranged toward the terminal plate 912.

[0104] By making the step face 91113 of the step flush with the plane where the wall portion 81 and the negative temperature coefficient thermistor 20 abut, when the negative temperature coefficient thermistor 20 is clamped between the terminal plate 912 and the wall portion 81, the negative temperature coefficient thermistor 20 also abuts against the step face 91113 of the step at the same time, which increases the contact area between the negative temperature coefficient thermistor 20 and the terminal main body 911, and is beneficial to reducing the contact resistance between the negative temperature coefficient thermistor 20 and the terminal main body 911.

[0105] In some embodiments, with reference to Figure 9 The terminal main body 911 includes a main body portion 9111 and a protruding portion 9112 protruding from the outer periphery of the main body portion 9111, the main body portion 9111 is connected to the terminal plate 912 through the electrode lead-out hole 811, the protruding portion 9112 is located in the shell 8 and covers the electrode lead-out hole 811, and the negative temperature coefficient thermistor 20 is clamped between the protruding portion 9112 and the wall portion 81.

[0106] The main body portion 9111 can be a main body structure in the terminal main body 911, and the protruding portion 9112 is a structure protruding outward from the outer peripheral surface of the main body portion 9111, which is located in the shell 8 and covers the electrode lead-out hole 811. The protruding portion 9112 can clamp the wall portion 81 from the inner and outer sides of the wall portion 81 with the terminal plate 912, so that the first electrode terminal 91 is connected to the wall portion 81.

[0107] The main body portion 9111 connected to the terminal plate 912 through the electrode lead-out hole 811 can mean that the main body portion 9111 passes through the electrode lead-out hole 811 and extends from the electrode lead-out hole 811 to be connected to the terminal plate 912, so that the terminal main body 911 can be connected to the terminal plate 912.

[0108] The negative temperature coefficient thermistor 20 is clamped between the protruding portion 9112 and the wall portion 81. The negative temperature coefficient thermistor 20 can be located between the protruding portion 9112 and the wall portion 81, and the protruding portion 9112 and the wall portion 81 clamp the negative temperature coefficient thermistor 20. By clamping the negative temperature coefficient thermistor 20 between the protruding portion 9112 and the wall portion 81, the negative temperature coefficient thermistor 20 is located in the shell 8, and the negative temperature coefficient thermistor 20 can be protected by the shell 8.

[0109] In some embodiments, with reference to Figure 10 The negative temperature coefficient thermistor 20 is provided with a mounting hole 203, and the negative temperature coefficient thermistor 20 is fitted on the terminal body 911 through the mounting hole 203.

[0110] The mounting hole 203 can be a hole-shaped structure provided in the negative temperature coefficient thermistor 20 and penetrating in the thickness direction of the wall portion 81, which is used to fit the negative temperature coefficient thermistor 20 on the terminal body 911, so that the negative temperature coefficient thermistor 20 can be connected with the first electrode terminal 91 on the wall portion 81, and the negative temperature coefficient thermistor 20 is easy to install.

[0111] The negative temperature coefficient thermistor 20 is fitted on the terminal body 911 through the mounting hole 203. The terminal body 911 can be interference-fitted with the mounting hole 203 of the negative temperature coefficient thermistor 20, or the terminal body 911 can be clearance-fitted with the mounting hole 203 of the negative temperature coefficient thermistor 20, or the terminal body 911 can be transition-fitted with the mounting hole 203 of the negative temperature coefficient thermistor 20.

[0112] By fitting the negative temperature coefficient thermistor 20 on the terminal body 911 through the mounting hole 203, not only the inner surface of the mounting hole 203 can well fit the outer peripheral surface of the terminal body 911, so that the negative temperature coefficient thermistor 20 can stably contact with the terminal body 911, but also the possibility of the metal wire on the electrode body 101 or the terminal plate 912 contacting with the wall portion 81 can be reduced.

[0113] In some embodiments, with reference to Figure 11 The negative temperature coefficient thermistor 20 is provided with a threaded hole 204, and the negative temperature coefficient thermistor 20 is connected to the outer periphery of the terminal body 911 through the threaded hole 204.

[0114] The negative temperature coefficient thermistor 20 is connected to the outer periphery of the terminal body 911 through the threaded hole 204, so that the negative temperature coefficient thermistor 20 is threadedly connected with the terminal body 911, the firmness of the connection between the negative temperature coefficient thermistor 20 and the terminal body 911 is improved, and the stability of the electrical connection between the wall portion 81 and the first electrode terminal 91 when the negative temperature coefficient thermistor 20 is turned on is improved, which is conducive to reducing the contact resistance.

[0115] In some embodiments, the terminal plate 912 and the wall portion 81 are riveted through the terminal body 911.

[0116] The riveting of the terminal plate 912 and the wall portion 81 through the terminal body 911 can mean that the terminal plate 912 is provided with a riveting hole coaxially arranged with the electrode lead-out hole 811, the terminal body 911 passes through the electrode lead-out hole 811 and the riveting hole in sequence, part of the structure of the terminal body 911 is deformed and transformed by being upset in the riveting hole to be connected with the terminal plate 912, and part of the terminal body 911 located on the side of the wall portion 81 close to the electrode assembly 10 abuts against the wall portion 81, so as to realize the riveting of the wall portion 81 and the terminal plate 912 to firmly hold the negative temperature coefficient thermistor 20.

[0117] In some embodiments, the battery monomer 7 further comprises a first insulating member 40 and a second insulating member 50, at least part of the first insulating member 40 is arranged between the terminal plate 912 and the wall portion 81, and at least part of the second insulating member 50 is located in the electrode lead-out hole 811 and clamped between the terminal body 911 and the wall portion 81.

[0118] The first insulating member 40 can be a component with insulating properties. The first insulating member 40 is at least partially arranged between the terminal plate 912 and the wall portion 81, so that the wall portion 81 and the terminal plate 912 can be kept insulated from each other when the negative temperature coefficient thermistor 20 is in a non-conductive state. Exemplarily, at least part of the first insulating member 40 is arranged in the gap between the wall portion 81 and the terminal plate 912.

[0119] By connecting the first insulating member 40 to the wall portion 81 at the electrode lead-out hole 811, the first insulating member 40 can isolate the wall portion 81 from the terminal plate 912 when the negative temperature coefficient thermistor 20 is in a non-conductive state, so that the wall portion 81 and the terminal plate 912 are insulated from each other, the wall portion 81 is not electrified, and the wall portion 81 is less likely to be electrically connected with external devices.

[0120] The second insulating member 50 can be a member having insulating properties. At least a portion of the second insulating member 50 is arranged in the electrode lead-out hole 811 and clamped between the terminal body 911 and the wall portion 81, which not only can insulate and isolate the wall portion 81 from the terminal body 911 when the negative temperature coefficient thermistor 20 is in a non-conductive state, but also can seal the gap between the terminal body 911 and the inner wall of the electrode lead-out hole 811, which is conducive to improving the sealing performance of the internal space of the battery monomer 7.

[0121] Some embodiments of the present application also provide a battery device 2, which comprises the battery monomer 7 provided in the above technical solutions.

[0122] Some embodiments of the present application also provide a power utilization device, which comprises the battery device 2 provided in the above technical solutions, and the battery device 2 is used to provide electric energy.

[0123] Some embodiments of the present application provide a battery monomer 7, which comprises a shell 8, an electrode terminal assembly 9, an electrode assembly 10, a negative temperature coefficient thermistor 20 and an adapter 30. The shell 8 comprises a wall portion 81, and the electrode terminal assembly 9 is arranged in the wall portion 81. The electrode terminal assembly 9 comprises first and second electrode terminals 91 and 92 with opposite polarities. The first and second electrode terminals 91 and 92 are both electrically connected to the wall portion 81 through the negative temperature coefficient thermistor 20. The terminal plate 912 of the first electrode terminal 91 is located on the outer side of the wall portion 81 away from the electrode assembly 10. The terminal body 911 extends from the electrode lead-out hole 811 of the wall portion 81 and is connected to the terminal plate 912. The negative temperature coefficient thermistor 20 is clamped between the terminal plate 912 and the wall portion 81. The negative temperature coefficient thermistor 20 is configured to electrically connect the first and second electrode terminals 91 and 92 when the temperature exceeds a first threshold value. The first electrode terminal 91 is connected to the electrode assembly 10 through the adapter 30. The second electrode terminal 92 is connected to the electrode assembly 10 through the adapter 30. The adapter 30 is provided with a fuse structure 301, which is configured to cut off the connection between the electrode assembly 10 and the electrode terminal assembly 9 when the temperature exceeds a second threshold value. The second threshold value is greater than the first threshold value.

[0124] In the above structure, when the temperature of the battery cell 7 exceeds the first threshold value, the first electrode terminal 91 and the second electrode terminal 92 are electrically connected in conduction, the internal circuit of the battery cell 7 is short-circuited, a larger current flows through the fuse structure 301 in the adapter 30, the temperature of the fuse structure 301 is raised, and when the temperature of the fuse structure 301 exceeds the second threshold value, the connection between the electrode assembly 10 and the electrode terminal assembly 9 is cut off, the internal circuit of the battery cell 7 is broken, the possibility of heat generation of the battery cell 7 is reduced, the possibility of thermal runaway of the battery cell 7 is reduced, and the reliability of the battery cell 7 is improved. In addition, since the negative temperature coefficient thermistor 20 does not accompany mechanical action when the first electrode terminal 91 and the second electrode terminal 92 are in conduction, the contact area of the internal circuit of the battery cell 7 remains stable, and is not easy to cause sparking, so that when the temperature of the battery cell 7 exceeds the first threshold value, the battery cell 7 can be short-circuited in time.

[0125] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. Especially, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The battery monomer comprises: a shell comprising a wall portion; an electrode terminal assembly arranged on the wall portion, the electrode terminal assembly comprising first and second electrode terminals with opposite polarities; an electrode assembly accommodated in the shell; a negative temperature coefficient thermistor configured to electrically connect the first and second electrode terminals when a temperature exceeds a first threshold value; an adapter accommodated in the shell, the adapter connecting the electrode assembly and the electrode terminal assembly, the adapter being provided with a fuse structure configured to cut off the connection between the electrode assembly and the electrode terminal assembly when a temperature exceeds a second threshold value, the second threshold value being greater than the first threshold value.

2. The battery cell of claim 1, wherein, The first electrode terminal is electrically connected to the wall portion through the negative temperature coefficient thermistor, and the second electrode terminal is electrically connected to the wall portion.

3. The battery cell of claim 1, wherein, The first electrode terminal is electrically connected to the wall portion through the negative temperature coefficient thermistor, and the second electrode terminal is electrically connected to the wall portion through the negative temperature coefficient thermistor.

4. The battery cell according to any one of claims 1 to 3, characterized in that, The wall portion is provided with an electrode lead-out hole, the first electrode terminal comprises a terminal body and a terminal plate connected to each other, the terminal plate is located on the outer side of the wall portion away from the electrode assembly, and the terminal body is arranged in the electrode lead-out hole and connected to the adapter.

5. The battery cell of claim 4, wherein, The negative temperature coefficient thermistor is clamped between the terminal plate and the wall portion.

6. The battery cell of claim 5, wherein, A first conductive adhesive structure is arranged between the negative temperature coefficient thermistor and the terminal plate, and a second conductive adhesive structure is arranged between the negative temperature coefficient thermistor and the wall portion.

7. The battery cell according to claim 5 or 6, characterized in that An outer surface of the wall portion away from the electrode assembly is recessed inward to form a recess, and at least part of the negative temperature coefficient thermistor is arranged in the recess.

8. The battery cell of any one of claims 5-7, wherein, The terminal body comprises a large-diameter section and a small-diameter section connected to each other along the thickness direction of the wall portion, the large-diameter section and the small-diameter section form a step, a step surface of the step is flush with a plane where the wall portion and the negative temperature coefficient thermistor abut, and the step surface abuts against the negative temperature coefficient thermistor.

9. The battery cell of claim 4, wherein, The terminal body comprises a main body portion and a protruding portion protruding from the outer periphery of the main body portion, the main body portion is connected to the terminal plate through the electrode lead-out hole, the protruding portion is located in the shell and covers the electrode lead-out hole, and the negative temperature coefficient thermistor is clamped between the protruding portion and the wall portion.

10. The battery cell of any one of claims 4-9, wherein, The negative temperature coefficient thermistor is provided with a mounting hole, and the negative temperature coefficient thermistor is fitted on the terminal body through the mounting hole.

11. The battery cell of any one of claims 4-9, wherein, The negative temperature coefficient thermistor is provided with a threaded hole, and the negative temperature coefficient thermistor is connected to the outer periphery of the terminal body through the threaded hole.

12. The battery cell of any one of claims 4-11, wherein, The terminal plate and the wall portion are riveted through the terminal body.

13. The battery cell of any one of claims 4-12, wherein, The battery monomer further comprises first and second insulating members, at least part of the first insulating member is arranged between the terminal plate and the wall portion, and at least part of the second insulating member is located in the electrode lead-out hole and clamped between the terminal body and the wall portion.

14. A battery device characterized by comprising: The battery monomer comprises the battery monomer according to any one of claims 1 to 13.

15. An electrical device, comprising: A battery device as claimed in claim 14 for providing electrical energy.

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