WO2023050923A1

WO2023050923A1 - Battery cell, battery, and electric device

Info

Publication number: WO2023050923A1
Application number: PCT/CN2022/100843
Authority: WO
Inventors: 李雪; 刘江; 钟礼斌
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2021-09-30
Filing date: 2022-06-23
Publication date: 2023-04-06
Also published as: CN219303777U

Abstract

The present application relates to a battery cell, a battery, and an electric device. The battery cell comprises a casing, an electrode assembly, and a semiconductor cooling/heating device, wherein the casing has an accommodating cavity; the electrode assembly is accommodated in the accommodating cavity; and the semiconductor cooling/heating device is provided on the casing and is configured to heat or cool the electrode assembly. According to the battery cell provided in the embodiments of the present application, a heating or cooling device can be closer to the electrode assembly of the battery cell, thereby reducing the time taken for transferring the temperature of a heat source or a cold source to the electrode assembly and thus improving the heat transfer efficiency.

Description

Battery cells, batteries and electrical devices

technical field

The present application relates to the field of battery technology, in particular to a battery cell, a battery and an electrical device.

Background technique

The optimal working temperature of lithium-ion batteries is 20-40°C. Excessively high temperatures will accelerate battery capacity attenuation, cause battery aging, reduce battery life, and even cause safety accidents such as thermal runaway. Therefore, it is necessary to increase cooling measures. To cool down the battery when the battery temperature is too high.

At the same time, the lithium-ion battery is in a low temperature environment, which also has a great impact on the discharge performance, for example, affecting the cruising range of the car, and even failures such as difficulty in starting. In addition, too low a temperature will cause irreversible damage to the battery. The long winter in northern my country limits the application of lithium-ion batteries, so it is necessary to take heating measures for batteries in low-temperature environments; increase the temperature of batteries during discharge, thereby improving battery discharge capacity and improving user experience.

In some cases, air cooling, liquid cooling, heating film heating, etc. are used to cool or heat the battery, but the effect is still not ideal, especially during the battery charging process, because the battery temperature will rise rapidly, the cooling speed It is far from meeting the needs, and in an environment with lower temperature, because the temperature of the battery drops faster, the above cooling method also cannot make the battery heat up to the optimum temperature range quickly.

Contents of the invention

Based on this, it is necessary to provide a battery cell, a battery and a battery for the problem that the distance between the heating or cooling device and the electrode assembly of the battery cell is relatively long, and the temperature of the heat source or cold source is transmitted to the electrode assembly for a long time. electric device.

According to the first aspect of the embodiments of the present application, there is provided a battery cell, the housing has a housing chamber; the electrode assembly is accommodated in the housing chamber; a semiconductor cooling and heating device is provided on the housing for heating or cooling the electrode assembly.

In the embodiment of the present application, the semiconductor cooling and heating device is arranged on the outer casing of the battery cell, so that the semiconductor cooling and heating device can be close to the electrode assembly at a short distance, so that the electrode assembly can be cooled quickly when the temperature of the electrode assembly is too high, and the electrode assembly When the temperature is too low, the electrode assembly is heated quickly, which shortens the time for the temperature of the semiconductor cooling and heating device to transfer to the electrode assembly, and improves the heat transfer efficiency.

By adopting the above-mentioned scheme, since the influence of high temperature and low temperature on the battery mainly acts on the electrode assembly of the battery cell, the above-mentioned scheme of the present application sets the semiconductor cooling and heating device on the shell of the battery cell, so that the semiconductor cooling and heating device can The electrode assembly is close to the electrode assembly at a short distance, thereby rapidly cooling the electrode assembly when the temperature of the electrode assembly is too high, and rapidly heating the electrode assembly when the temperature of the electrode assembly is too low. The time for transferring the temperature of the semiconductor cooling and heating device to the electrode assembly is shortened, and the heat transfer efficiency is improved.

In some embodiments, the semiconductor cooling and heating device is embedded on the side wall of the casing, and is at least partially exposed in the accommodating cavity.

By adopting the above scheme, the part of the semiconductor cooling and heating device exposed in the accommodating chamber is closer to the electrode assembly and is in the same space as the electrode assembly, thereby cooling or heating the electrode assembly at a closer distance and improving heat transfer efficiency.

In some embodiments, the part of the semiconductor cooling and heating device located in the accommodating cavity is in contact with the electrode assembly.

By adopting the above solution, the semiconductor cooling and heating device transfers heat through direct contact with the electrode assembly, further improving the heat transfer efficiency.

In some embodiments, the side wall of the casing is provided with a through hole penetrating the side wall of the casing, the semiconductor cooling and heating device is embedded in the through hole, and a first sealing member is provided between the semiconductor cooling and heating device and the hole wall of the through hole , to seal the via.

By adopting the above solution, the electrolyte in the shell is not easy to leak from between the semiconductor cooling and heating device and the inner wall of the through hole, which ensures the normal use of the battery cell and ensures the safety of the battery cell.

In some embodiments, the battery cell further includes a second sealing member, the second sealing member is located on the side of the semiconductor cooling and heating device away from the electrode assembly, and is sealingly connected with the side wall of the casing.

By adopting the above scheme, the semiconductor cooling and heating device is protected, preventing external force from pushing the semiconductor cooling and heating device to the inside of the battery cell to destroy the seal between the semiconductor cooling and heating device and the through hole or preventing the semiconductor cooling and heating device from being exposed to the outside and being damaged. damage. In addition, the second seal further isolates the inside and outside of the battery cell, preventing the electrolyte from flowing from the inside of the battery cell to the outside.

In some embodiments, a boss is provided on the outside of the side wall of the casing, and the boss is arranged around the circumference of the through hole. Hot and cold device.

By adopting the above scheme, when other components whose size is larger than the limited range of the boss are close to the surface of the shell where the semiconductor cooling and heating device is located, they first touch the boss, and it is not easy to directly squeeze the semiconductor cooling and heating device, thereby preventing the semiconductor cooling and heating device from /or the connection structure between the semiconductor cooling and heating device and the shell is damaged.

In some embodiments, the semiconductor cooling and heating device includes an NP module, and the NP module includes a first-type conductive element, an N-type semiconductor, a second-type conductive element, a P-type semiconductor, and a first-type conductive element that are electrically connected in sequence;

The second type of conductive member is used for cooling when the current flows from the N-type semiconductor to the P-type semiconductor, and for heating when the current flows from the P-type semiconductor to the N-type semiconductor.

By adopting the above scheme, the semiconductor cooling and heating device can realize cooling and heating in different processes, so that only one semiconductor cooling and heating device can be used to cool or heat the battery cells at different times by changing the current flow direction, The structure of the battery cell is simplified and the cost is saved.

In some embodiments, the semiconductor cooling and heating device is connected in series between the positive pole and the positive pole or between the negative pole and the negative pole;

When the battery cell is charged, the current flows from the N-type semiconductor to the P-type semiconductor;

When a battery cell is discharged, current flows from the P-type semiconductor to the N-type semiconductor.

By adopting the above scheme, the semiconductor cooling and heating device is connected in series in the circuit of the battery cell, the semiconductor cooling and heating device is automatically cooled during the charging process of the battery cell, and the battery cell is automatically heated during the discharge process of the battery cell; The cooling process is carried out during the rapid temperature rise process of battery cell charging, and the heating process is carried out during the cooling process of battery cell discharge, so there is no need to design a separate circuit to control when the semiconductor cooling and heating device is cooling and when heating , The control of the semiconductor cooling and heating device is more convenient.

In some embodiments, the semiconductor cooling and heating device is electrically connected to the positive pole and/or the positive pole lug through a wire; or, the semiconductor cooling and heating device is electrically connected to the negative pole and/or the negative pole lug through a wire.

By adopting the above scheme, the semiconductor cooling and heating device can be reasonably arranged according to the internal space of the battery cell, and then the semiconductor cooling and heating device is connected in series with the circuit of the battery cell through wires, without limiting the semiconductor cooling and heating device to the positive pole and the battery cell. The space between the positive pole lugs, or the space between the negative pole pole and the negative pole lug, makes the installation of semiconductor cooling and heating devices more flexible.

In some embodiments, a wire clamp assembly is provided on the side wall of the housing for fixing the wires on the housing.

By adopting the above solution, it is possible to prevent the wires from being entangled in the electrolyte in the housing, or to slow down the aging speed of the wires soaked in the electrolyte for a long time.

In some embodiments, the clamping assembly includes two clamping jaws, the clamping jaws include a body portion and a limiting portion connected to one end of the body portion, the end of the body portion away from the limiting portion is fixed on the side wall of the housing, and the two limiting portions The distance between the bit parts is smaller than the distance between the two body parts.

By adopting the above scheme, when the wire is located between the body parts of the two jaws, since the distance between the limiting parts of the two jaws is small, the wire is not easy to be separated from between the two jaws, thereby The wire is relatively firmly limited between the two jaws.

According to the second aspect of the embodiments of the present application, a battery is provided, including the battery cell of the above embodiment.

According to a third aspect of the embodiments of the present application, there is provided an electric device, including the battery of the foregoing embodiments.

Description of drawings

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 embodiment. The drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the application. Also, the same reference numerals are used to denote the same components throughout the drawings. In the attached picture:

FIG. 1 is a schematic structural view of an electrical device in an embodiment of the present application;

FIG. 2 is a schematic structural view of a battery in an embodiment of the present application;

FIG. 3 is a schematic structural diagram of a battery module in an embodiment of the present application;

FIG. 4 is a schematic diagram of an exploded structure of a battery cell in an embodiment of the present application;

Fig. 5 is a schematic structural view of an end cap in an embodiment of the present application;

Fig. 6 is a schematic cross-sectional structure diagram along the A-A plane in Fig. 5;

Figure 7 is an enlarged schematic view of part C in Figure 6;

Fig. 8 is a schematic cross-sectional structure diagram along the B-B plane in Fig. 5 .

Explanation of reference signs: 2, automobile; 200, battery; 210, controller; 220, motor; 300, battery module; 201, first box body; 202, second box body; 400, battery cell; 20, shell ; 21, shell; 211, accommodation cavity; 22, end cover; 221, positive terminal; 222, negative terminal; 223, through hole; 224, boss; 2241, outer surface; 30, electrode assembly; 31, positive pole Ear; 32. Negative pole ear; 40. Semiconductor cooling and heating device; 41. First insulating part; 42. Second insulating part; 43. NP module; 431. First type conductive part; 432. N-type semiconductor; 433. The second type of conductive part; 434, P-type semiconductor; 50, the first seal; 60, the second seal; 70, wire; 80, clamping assembly; department.

Detailed ways

Embodiments of the technical solutions of the present application will be described in detail below in conjunction with the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and therefore are only examples, rather than limiting the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the application; the terms used herein are only for the purpose of describing specific embodiments, and are not intended to To limit this application; the terms "comprising" and "having" and any variations thereof in the specification and claims of this application and the description of the above drawings are intended to cover a non-exclusive inclusion.

In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects, and should not be understood as indicating or implying relative importance or implicitly indicating the number, specificity, or specificity of the indicated technical features. Sequence or primary-secondary relationship. In the description of the embodiments of the present application, "plurality" means two or more, unless otherwise specifically defined.

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 application. The occurrences of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is understood explicitly and implicitly by those skilled in the art that the embodiments described herein can be combined with other embodiments.

In the description of the embodiment of the present application, the term "and/or" is only a kind of association relationship describing associated objects, which means that there may be three kinds of relationships, such as A and/or B, which may mean: A exists alone, and A exists at the same time and B, there are three cases of B alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), similarly, "multiple groups" refers to more than two groups (including two), and "multiple pieces" refers to More than two pieces (including two pieces).

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", etc. indicate the orientation or positional relationship based on the drawings Orientation or positional relationship is only for the convenience of describing the embodiment of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as an implementation of the present application. Example limitations.

In the description of the embodiments of this application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "connection" and "fixation" should be interpreted in a broad sense, for example, it can be a fixed connection or a fixed connection. Disassembled connection, or integration; it can also be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the embodiments of the present application according to specific situations.

The basic unit that constitutes the battery is a battery cell. The battery cell includes a casing, an electrode assembly, and an electrolyte. The electrode assembly is composed of a positive pole piece, a negative pole piece, and a separator. A battery cell works primarily by moving metal ions between the positive and negative pole pieces. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer is coated on the surface of the positive electrode current collector, and the positive electrode collector without the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. Fluid, the positive electrode current collector not coated with the positive electrode active material layer is used as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer is coated on the surface of the negative electrode current collector, and the negative electrode collector without the negative electrode active material layer protrudes from the negative electrode collector coated with the negative electrode active material layer. Fluid, the negative electrode current collector not coated with the negative electrode active material layer is used as the negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon or silicon. In order to ensure that a large current is passed without fusing, the number of positive pole tabs is multiple and stacked together, and the number of negative pole tabs is multiple and stacked together. The material of the isolation film can be PP or PE.

During the use of the battery, it is often encountered that the temperature of the battery is too high. High temperature will accelerate the aging of the battery and reduce the service life of the battery. If the temperature is too high, it may even cause safety accidents such as thermal runaway. Therefore, it is usually necessary to cool the battery, and the commonly used cooling methods include natural cooling, forced air cooling, liquid cooling, and the like.

During the use of the battery, the temperature of the battery will be too low. Too low temperature has a great impact on the discharge performance of the lithium-ion battery. For example, when the battery is used in a car, the lower temperature will affect the performance of the car. If the cruising range is limited, there may even be failures such as difficulty in starting the car. In addition, if the temperature is too low, it may cause irreversible damage to the battery. This has also led to restrictions on the application of lithium-ion batteries in areas with long winters such as northern my country. Therefore, it is necessary to take heating measures for batteries in low-temperature environments to increase the temperature of batteries during discharge, thereby improving the discharge capacity of batteries and reducing power consumption. The probability of failure of electrical devices can be reduced, and the user experience can be improved. The commonly used heating methods for batteries include electric heating film heating, PTC heating, liquid heating, etc.

However, when the battery is heated by the above-mentioned heating method or cooled by the above-mentioned cooling method, it is still unable to completely overcome the failure of the electric device caused by the temperature of the battery being too high or too low.

After long-term research, the applicant found that this is because the part of the battery that is more sensitive to temperature is usually the electrode assembly inside the battery cell, while the cooling device or heating device of the existing battery is generally installed outside the battery. The heat device is far away from the electrode assembly inside the battery cell, and it is difficult to quickly heat or cool the electrode assembly, which leads to the above-mentioned problems during the use of the battery.

In view of this, the present application provides a battery cell, which makes the distance between the semiconductor cooling and heating device and the electrode assembly of the battery cell closer by arranging a semiconductor cooling and heating device on the casing, and shortens the distance between the heat source or the cooling source. The temperature transfer time to the electrode assembly improves the heat transfer efficiency.

The battery cells provided in the embodiments of the present application can be applied to various devices using batteries, such as mobile phones, portable devices, notebook computers, battery cars, electric toys, electric tools, electric vehicles, ships and spacecraft, etc., for example, spacecraft Including, but not limited to, airplanes, rockets, space shuttles, and spaceships.

As shown in Figure 1, Figure 1 is a schematic structural diagram of an electrical device provided by an embodiment of the present application, and the electrical device is a car 2 as an example for illustration, and the car 2 can be a fuel car, a gas car or a new energy car , New energy vehicles can be pure electric vehicles, hybrid vehicles or extended-range vehicles. The car 2 includes a battery 200 , a controller 210 and a motor 220 . The battery 200 is used to supply power to the controller 210 and the motor 220 as the operating power and driving power of the car 2 , for example, the battery 200 is used for starting, navigating and running the car 2 . For example, the battery 200 supplies power to the controller 210, and the controller 210 controls the battery 200 to supply power to the motor 220, and the motor 220 receives and uses the power of the battery 200 as the driving power of the car 2, instead or partially replacing fuel oil or natural gas to provide driving for the car 2 power.

As shown in FIG. 2 , in order to enable the battery 200 to achieve a higher function to meet the usage requirements, the battery 200 may include a plurality of battery modules 300 electrically connected to each other, the battery 200 includes a box body, and the box body includes a first box body 201, a second box body Two boxes 202 and a plurality of battery modules 300, wherein the first box 201 and the second box 202 are fastened to each other, and the plurality of battery modules 300 are arranged in the first box 201 and the second box 202 to form an enclosure within the space. The first box body 201 and the second box body 202 can be made of aluminum, aluminum alloy or other metal materials. In some embodiments, the first box body 201 and the second box body 202 are hermetically connected.

As shown in FIG. 3 , the battery module 300 may include one or more battery cells 400. When the battery module 300 includes a plurality of battery cells 400, the plurality of battery cells 400 may be electrically connected in series, in parallel or in parallel. Connected to achieve larger current or voltage, where hybrid refers to a combination of series and parallel. In addition, multiple battery cells 400 can be arranged according to predetermined rules. As shown in FIG. 3 , the battery cells 400 can be placed vertically, the height direction of the battery cells 400 is consistent with the Z direction, and the multiple battery cells 400 are arranged side by side along the Y direction. Or, the battery cells 400 can be placed flat, the width direction of the battery cells 400 is consistent with the Z direction, and a plurality of battery cells 400 can be stacked in at least one layer along the Z direction, and each layer includes an arrangement along the X direction or the Y direction. A plurality of battery cells 400.

As shown in FIG. 4 , FIG. 4 is a battery cell 400 provided in the embodiment of the present application, which includes a casing 20 , an electrode assembly 30 and a semiconductor cooling and heating device 40 .

The casing 20 has an accommodating chamber 211 ; the electrode assembly 30 is accommodated in the accommodating chamber 211 ; the semiconductor cooling and heating device 40 is provided on the casing 20 for heating or cooling the electrode assembly 30 .

As shown in FIG. 4 , in some embodiments, the casing 20 includes a casing 21 and an end cap 22 that cooperates with the casing 21 to seal the electrode assembly 30 in the casing 21. The casing 21 is a hollow cavity, for example , one of the surfaces of the casing 21 has an opening, that is, the plane does not have a wall of the casing 21 so that the inside and outside of the casing 21 communicate, so that the electrode assembly 30 can be accommodated in the casing 21, and the end cap 22 is at the opening of the casing 21 Combined with the housing 21 to form a hollow cavity.

The casing 21 depends on the combined shape of one or more electrode assemblies 30, for example, the casing 21 can be a hollow cuboid, a hollow cube, or a hollow cylinder. For example, when the housing 21 is a hollow cuboid or cube, one of the planes of the housing 21 is an open surface, that is, the plane does not have a housing 21 wall so that the inside and outside of the housing 21 communicate; when the housing 21 is a hollow cylinder One of the circular sides of the housing 21 is an open surface, that is, the circular side does not have a wall of the housing 21 so that the inside and outside of the housing 21 communicate.

In another embodiment of the present application, the casing 21 can be made of metal material or plastic, and in one embodiment, the casing 21 is made of aluminum or aluminum alloy.

As shown in Figure 4 and Figure 5, Figure 5 is a schematic structural view of the end cover in an embodiment of the present application, two electrode terminals are provided on the end cover 22, and the end cover 22 is combined with the housing 21 at the opening of the housing 21 and Covering the opening of the casing 21 , for example, the end cap 22 can be a metal plate, and is connected to the casing 21 by welding, so as to seal the electrode assembly 30 in the casing 21 .

The two electrode terminals are respectively a positive terminal 221 and a negative terminal 222 , and the electrode terminals are electrically connected to the electrode assembly 30 . Each electrode assembly 30 has a positive pole tab 31 and a negative pole tab 32. The positive pole tab 31 of one or more electrode assemblies 30 is connected to the positive terminal 221, and the negative pole tab 32 of one or more electrode assemblies 30 is connected to the negative pole terminal 222. connect.

In some embodiments, the semiconductor cooling and heating device 40 is disposed on the casing 21 of the casing 20 .

In some other embodiments, the semiconductor cooling and heating device 40 may also be disposed on the end cover 22 of the housing 20 , which is not limited in this embodiment of the present application.

In the relevant drawings of the following embodiments, only the semiconductor cooling and heating device 40 is arranged on the end cover 22 for schematic illustration. Those skilled in the art should be able to understand that the structure of the semiconductor cooling and heating device 40 being arranged on the housing 21 It is the same as that provided on the end cap 22 .

The semiconductor cooling and heating device 40 is a device for cooling or heating through the Peltier effect, that is, the movement of charge carriers in the conductor forms an electric current. Since the charge carrier is at different energy levels in different materials, when it moves from a high energy level to a low energy level, it releases excess energy; on the contrary, when it moves from a low energy level to a high energy level, it absorbs energy from the outside. Energy is absorbed or released in the form of heat at the interface of two materials.

Therefore, when currents in different directions pass through the semiconductor cooling and heating device 40, at least one part of the semiconductor cooling and heating device 40 can heat up or cool down, that is, by changing the direction of the current, the same semiconductor cooling and heating device 40 can cool or cool the electrode assembly 30. Heating is beneficial to simplify the structure of the battery cell 400 and save costs.

In the above scheme of the present application, the semiconductor cooling and heating device 40 is installed on the casing 20 of the battery cell 400, so that the semiconductor cooling and heating device 40 can be close to the electrode assembly 30, so that the electrode assembly 30 can be cooled quickly when the temperature of the electrode assembly 30 is too high 30, and rapidly heating the electrode assembly 30 when the temperature of the electrode assembly 30 is too low. The time for transferring the temperature of the semiconductor cooling and heating device 40 to the electrode assembly 30 is shortened, and the heat transfer efficiency is improved.

As shown in Fig. 4, Fig. 5 and Fig. 6, Fig. 6 is a schematic cross-sectional view of the A-A plane in Fig. exposed in the accommodation chamber 211.

By embedding, the part of the semiconductor cooling and heating device 40 exposed in the accommodating chamber 211 is closer to the electrode assembly 30 and in the same space as the electrode assembly 30, so that the temperature of the electrode assembly 30 can be lowered or heated at a closer distance. Further improve heat transfer efficiency.

In some embodiments, the part of the semiconductor cooling and heating device 40 located in the accommodating cavity 211 is in contact with the electrode assembly 30 . Since the thermal conductivity of a solid is generally greater than that of a gas, the direct contact between the semiconductor cooling and heating device 40 and the electrode assembly 30 can further improve the heat transfer efficiency, so that the semiconductor cooling and heating device 40 can more quickly contact the electrode assembly 30. For cooling or heating.

As shown in FIG. 7, FIG. 7 is an enlarged schematic diagram of position C in FIG. In the through hole 223 , a first sealing member 50 is provided between the semiconductor cooling and heating device 40 and the wall of the through hole 223 to seal the through hole 223 .

The shape of the through hole 223 can be various shapes such as a circle or a square, which is not limited in the embodiment of the present application. In one embodiment, the shape of the through hole 223 is adapted to at least one cross-sectional profile of the semiconductor cooling and heating device 40 For example, when a cross-sectional profile of the semiconductor cooling and heating device 40 is a rectangle, the shape of the through hole 223 is also a square, and when a cross-sectional profile of the semiconductor cooling and heating device 40 is a circle, the shape of the through hole 223 is also a circle .

In some embodiments, the first sealing member 50 is made of a liquid-impermeable and elastic soft material such as rubber, plastic, silicone, etc., so that the first sealing member 50 can fill the semiconductor cooling and heating device 40 and the through hole through its own deformation. 223 to achieve the effect of sealing the through hole 223.

After the first sealing member 50 is provided, the electrolyte in the casing 20 is not easy to leak from between the semiconductor cooling and heating device 40 and the inner wall of the through hole 223, which ensures that the battery cell 400 can be used normally and that the battery cell 400 can be used safety.

As shown in FIG. 7 , in some embodiments, the battery cell 400 further includes a second sealing member 60 , the second sealing member 60 is located on the side of the semiconductor cooling and heating device 40 away from the electrode assembly 30 , and is connected to the side wall of the housing 20 Sealed connection.

The second sealing member 60 can be a metal part or a non-metal part, and is sealed and connected with the side wall of the housing 20 by means of welding, bonding or screwing.

In some embodiments, the material of the second sealing member 60 is the same as that of the side wall of the housing 20 , so as to facilitate welding connection with the side wall of the housing 20 .

The setting of the second seal 60 protects the semiconductor cooling and heating device 40 and prevents the semiconductor cooling and heating device 40 from being pushed to the inside of the battery cell 400 by an external force during subsequent manufacturing or use, thus damaging the semiconductor cooling and heating device 40 and the through hole 223 The seal between them or prevent the semiconductor cooling and heating device 40 from being exposed to the outside and being damaged.

In addition, the second sealing member 60 further isolates the inside and outside of the battery cell, preventing the electrolyte from flowing from the inside of the battery cell 400 to the outside.

As shown in FIG. 7 , in some embodiments, a boss 224 is provided on the outside of the side wall of the casing 20 , and the boss 224 is arranged around the through hole 223 , and the surface of the semiconductor cooling and heating device 40 facing the outside of the battery cell 400 is lower than The outer surface 2241 of the boss 224 is used to prevent external force from pressing the semiconductor cooling and heating device 40 .

Wherein, the outer surface 2241 of the boss 224 refers to a surface away from the accommodating cavity 211 .

The surface of the semiconductor cooling and heating device 40 toward the outside of the battery cell 400 is lower than the outer surface 2241 of the boss 224 based on the orientation in FIGS. 6 and 7 , that is, when the surface of the semiconductor cooling and heating device 40 faces upward, The surface of the semiconductor cooling and heating device 40 facing the outside of the battery cell 400 is lower than the outside surface 2241 of the boss 224 .

By adopting the above scheme, when other components whose size is larger than the limit range of the boss 224 are close to the surface of the housing 20 where the semiconductor cooling and heating device 40 is located, they will first contact the boss 224, and it is not easy to directly squeeze the semiconductor cooling and heating device 40, thereby preventing The semiconductor cooling and heating device 40 and/or the connection structure between the semiconductor cooling and heating device 40 and the housing 20 is damaged.

As shown in FIG. 7, in some embodiments, the semiconductor cooling and heating device 40 includes an NP module 43, and the NP module 43 includes a first type conductive member 431, an N-type semiconductor 432, a second type conductive member 433, P-type semiconductor 434, first type conductor 431; hot. The N-type semiconductor 432 has excess electrons and has a negative temperature difference potential; the P-type semiconductor 434 has insufficient electrons and has a positive temperature difference potential; when electrons pass through the junction from the P-type semiconductor 434 to the N-type semiconductor 432, the temperature of the junction decreases, Its energy must increase, and the increased energy is equivalent to the energy consumed by the node. On the contrary, when electrons flow from the N-type semiconductor 432 to the P-type semiconductor 434 , the temperature of the junction will increase, that is, the purpose of cooling and heating can be achieved by changing the direction of the current, and the temperature regulation of the battery 200 can be realized.

Wherein, a node in an NP module 43 refers to the second type conductive element 433 .

Of course, when a plurality of NP modules 43 are connected end to end, that is, the first type conductive member 431 at the head end of one NP module 43 is connected to the first type conductive member 431 at the tail end of another NP module 43, at this time, this Two first-type conductive members 431 can be combined to form a whole. When current flows through multiple NP modules 43, the first-type conductive member 431 adjacent to the NP module 43 can also be realized as one of the nodes. Warming up or cooling down.

The main difference between the first-type conductive member 431 and the second-type conductive member 433 lies in their different connection positions in the NP module 43 , so that opposite temperature changes can be generated when current flows in different directions. As for the materials of the first type conductive element 431 and the second type conductive element 433 , they may be the same or different, which is not limited in this embodiment of the present application. For example, both the first-type conductive member 431 and the second-type conductive member 433 may be one or a combination of copper, aluminum or other metal conductors.

Since the semiconductor cooling and heating device 40 can realize cooling and heating in different processes, only one semiconductor cooling and heating device 40 can be used to cool or heat the battery cell 400 at different times by changing the current flow direction, simplifying The structure of the battery cell 400 is improved, and the cost is saved.

In some embodiments, the semiconductor cooling and heating device 40 further includes two opposite first insulating parts 41 and second insulating parts 42, the NP module 43 is located between the first insulating part 41 and the second insulating part 42, the first The type conductive element 431 is in contact with the first insulating element 41 , and the second type conductive element 433 is in contact with the second insulating element 42 .

Exemplarily, the first type conductive element 431 is glued on the surface of the first insulating element 41 , and the second type conductive element 433 is glued on the surface of the second insulating element 42 .

The first insulator 41 and the second insulator 42 are used to insulate the NP module 43 from the outside when the semiconductor cooling and heating device 40 is energized, for example, one or both of the first insulator 41 and the second insulator 42 Both are made of ceramic materials, which have insulating properties and good heat conduction, and can transmit the temperature of the second type conductive member 433 to the external environment at a relatively fast speed.

In some embodiments, the first insulator 41 or the second insulator 42 can be placed close to the electrode assembly 30, so that the distance between the cooling or heating end of the semiconductor cooling and heating device 40 and the electrode assembly 30 is closer, so as to Heat exchange with the electrode assembly 30 at a faster speed.

In some embodiments, the semiconductor cooling and heating device 40 is connected in series between the positive pole pole and the positive pole tab 31;

Alternatively, the semiconductor cooling and heating device 40 is connected in series between the negative electrode pole and the negative electrode tab 32;

When the battery cell 400 is charged, the current flows from the N-type semiconductor 432 to the P-type semiconductor 434;

When the battery cell 400 is discharged, current flows from the P-type semiconductor 434 to the N-type semiconductor 432 .

From the above-mentioned embodiment, it can be seen that when the current flows from the N-type semiconductor 432 to the P-type semiconductor 434, the second-type conductive member 433 cools, and when the current flows from the P-type semiconductor 434 to the N-type semiconductor 432, the second-type conductive member 433 heats up. Therefore, using the above circuit structure to connect the semiconductor cooling and heating device 40 in series with the circuit of the battery cell 400, the semiconductor cooling and heating device 40 can be automatically cooled during the charging process of the battery cell 400, and the semiconductor cooling and heating device 40 can be automatically cooled during the discharge process of the battery cell 400. Among them, the effect of automatic heating of the battery cell 400; the cooling process is carried out during the rapid heating process of the battery cell 400 charging, and the heating process is carried out during the cooling process of the battery cell 400 discharge, so there is no need to design a separate The circuit controls when the semiconductor cooling and heating device 40 cools and when it heats up, and the control of the semiconductor cooling and heating device 40 is more convenient.

In some embodiments, the semiconductor cooling and heating device 40 is electrically connected to the positive pole and/or the positive tab 31 through a wire 70 (as shown in FIG. 8 );

Alternatively, the semiconductor cooling and heating device 40 is electrically connected to the negative electrode pole and/or the negative electrode tab 32 through the wire 70 .

By adopting the above scheme, the installation position of the semiconductor cooling and heating device 40 can be reasonably arranged according to the internal space of the battery cell 400, and then the semiconductor cooling and heating device 40 can be connected in series with the circuit of the battery cell 400 through the wire 70 without connecting the semiconductor cooling and heating device. The thermal device 40 is limited to the space between the positive pole and the positive tab 31 , or the space between the negative pole and the negative tab 32 , so that the installation of the semiconductor cooling and heating device 40 is more flexible.

As shown in FIG. 8 , which is a schematic cross-sectional view of plane B-B in FIG. 5 , in some embodiments, a wire clamp assembly 80 is provided on the side wall of the housing 20 for fixing the wire 70 on the housing 20 .

By adopting the above solution, it is possible to prevent the wire 70 from being entangled in the electrolyte solution in the housing 20 , or to slow down the aging speed of the wire 70 after soaking in the electrolyte solution for a long time.

In some embodiments, the clamping assembly 80 includes two jaws 81. The jaws 81 include a body portion 811 and a limiting portion 812 connected to one end of the body portion 811. The end of the body portion 811 away from the limiting portion 812 is fixed to the housing. On the side wall of 20 , the distance between the two limiting portions 812 is smaller than the distance between the two main body portions 811 .

In some embodiments, the jaw 81 is made of insulating materials such as plastic.

In some embodiments, the jaws 81 are elastic and can be deformed. In order to facilitate the wire 70 to enter between the body parts 811 of the two jaws 81, the distance between the limiting parts 812 of the two jaws 81 can be gradually reduced from the direction away from the body part 811 to the direction close to the body part 811. , when clamping the wire, put the wire 70 between the limiting parts 812 of the two jaws 81, and gradually approach between the body parts 811 of the two jaws 81, during this process, the extrusion of the wire 70 , so that the jaws 81 are deformed, and the two limiting parts 812 are gradually separated by the bending deformation of the jaws 81. When the wire 70 passes through the minimum distance between the two limiting parts 812, the wire 70 enters the two Between the body parts 811 of the jaws 81, because the distance between the two body parts 811 is relatively large, the two jaws 81 return to their original positions under their own elasticity. The distance between the limiting parts 812 of 81 is small, so as to prevent the wire 70 from falling out from between the two jaws 81 .

By adopting the above solution, the wire 70 is not easily separated from between the two clamping jaws 81 , so that the wire 70 is relatively firmly confined between the two clamping jaws 81 .

In summary, the embodiment of the present application arranges the semiconductor cooling and heating device 40 on the casing 20 of the battery cell 400, so that the semiconductor cooling and heating device 40 can be close to the electrode assembly 30, so that the temperature of the electrode assembly 30 is too high Rapidly cooling the electrode assembly 30 from time to time, and rapidly heating the electrode assembly 30 when the temperature of the electrode assembly 30 is too low, shortens the time for the temperature of the semiconductor cooling and heating device 40 to transfer to the electrode assembly 30, and improves heat transfer efficiency.

According to the second aspect of the embodiment of the present application, a battery 200 is provided, including the battery cell 400 of the above embodiment.

In the structure of the battery 200, the battery cell 400 itself is equipped with a semiconductor cooling and heating device 40, so as to perform rapid heating or cooling according to the actual temperature of the battery cell 400, and improve the efficiency of heat transfer. Or the temperature is too low to affect the life and failure.

According to a third aspect of the embodiments of the present application, there is provided an electric device, including the battery 200 of the above embodiments.

The electric device using the battery 200 is less likely to fail due to the temperature of the battery 200 during use.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present application, and the description thereof is relatively specific and detailed, but should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of protection of the patent application should be based on the appended claims.

Claims

A battery cell, comprising:

The shell has an accommodating cavity;

an electrode assembly housed in the chamber; and

The semiconductor cooling and heating device is arranged on the casing and is used for heating or cooling the electrode assembly.
The battery cell according to claim 1, wherein the semiconductor cooling and heating device is embedded on the side wall of the casing, and is at least partially exposed in the accommodating cavity.
The battery cell according to claim 2, wherein the part of the semiconductor cooling and heating device located in the accommodating cavity is in contact with the electrode assembly.
The battery cell according to claim 2, wherein a through hole penetrating through the side wall of the housing is provided on the side wall of the housing, and the semiconductor cooling and heating device is embedded in the through hole, so A first sealing member is provided between the semiconductor cooling and heating device and the hole wall of the through hole to seal the through hole.
The battery cell according to claim 4, wherein the battery cell further comprises a second sealing member, the second sealing member is located on the side of the semiconductor cooling and heating device away from the electrode assembly, and It is sealingly connected with the side wall of the housing.
The battery cell according to claim 4, wherein a boss is provided on the outside of the side wall of the casing, the boss is arranged around the circumference of the through hole, and the semiconductor cooling and heating device faces the battery The outer surface of the monomer is lower than the outer surface of the boss, so as to prevent external force from pressing the semiconductor cooling and heating device.
The battery cell according to any one of claims 1 to 6, wherein the semiconductor cooling and heating device includes an NP module, and the NP module includes a first-type conductive member, an N-type semiconductor, and an N-type semiconductor that are electrically connected in sequence. The second-type conductive element, the P-type semiconductor, and the first-type conductive element;

The second type conductive member is used for cooling when the current flows from the N-type semiconductor to the P-type semiconductor, and for heating when the current flows from the P-type semiconductor to the N-type semiconductor.
The battery cell according to claim 7, wherein:

The semiconductor cooling and heating device is connected in series between the positive pole and the positive tab; or between the negative pole and the negative tab;

When the battery cell is being charged, current flows from the N-type semiconductor to the P-type semiconductor;

When the battery cell is discharged, current flows from the P-type semiconductor to the N-type semiconductor.
The battery cell according to claim 8, wherein the semiconductor cooling and heating device is electrically connected to the positive pole and/or the positive tab through a wire;

Alternatively, the semiconductor cooling and heating device is electrically connected to the negative electrode pole and/or the negative electrode tab through wires.
The battery cell according to claim 9, wherein a wire clamping assembly is provided on the side wall of the housing for fixing the wires on the housing.
The battery cell according to claim 10, wherein the clamping assembly includes two clamping jaws, the clamping jaws include a body portion and a limiting portion connected to one end of the body portion, and the body portion An end away from the limiting portion is fixed on the side wall of the housing, and the distance between the two limiting portions is smaller than the distance between the two main body portions.
A battery, characterized by comprising the battery cell according to any one of claims 1-11.
An electrical device comprising the battery according to claim 12.