Battery cell, battery and electric device

Abstract

The utility model relates to a battery monomer, a battery and a power utilization device, and belongs to the technical field of batteries. The battery monomer comprises a shell, an electrode terminal and a pressure relief mechanism, the shell is provided with a first wall, the outer surface of the first wall comprises a first area and a second area, and the contact angle between the first area and electrolyte is larger than the contact angle between the second area and the electrolyte; at least one of the electrode terminal and the pressure relief mechanism is disposed in the first region. The first area and the second area with different contact angles are arranged on the first wall, so that the flow characteristics of the electrolyte on the first wall are different, and the electrode terminal and / or the pressure relief mechanism which are / is easy to corrode and difficult to clean are / is arranged in the first area, so that the electrolyte is more difficult to enrich in the first area; the electrolyte on the first wall can be effectively prevented from flowing to the position where the electrode terminal and / or the pressure relief mechanism is located, and important parts on the first area are effectively protected.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

[0003] In the development of battery technology, in addition to improving battery performance, safety issues and service life are also issues that cannot be ignored. In the process of manufacturing batteries, electrolytes may leak or overflow, which may cause varying degrees of corrosion to important structural components on the surface, and may also lead to battery safety accidents. Utility Model Content

[0004] The purpose of the present application is to provide a battery cell, a battery and an electrical device to improve the above problems, thereby improving the cleanability of overflowed electrolyte and improving the safety and long-term use of the battery.

[0005] In a first aspect, the present application provides a battery cell comprising a shell, an electrode terminal and a pressure relief mechanism, wherein the shell has a first wall, an outer surface of the first wall comprises a first region and a second region, a contact angle between the first region and an electrolyte is greater than a contact angle between the second region and the electrolyte; at least one of the electrode terminal and the pressure relief mechanism is disposed in the first region.

[0006] In the technical solution of the embodiment of the present application, by setting two first areas and second areas with different contact angles on the first wall, the flow characteristics of the electrolyte on the first wall are different. Specifically, the surface energy of the electrolyte in the first area is lower and the flow rate is faster, while the surface energy of the electrolyte in the second area is higher and the flow rate is slower. The electrolyte is relatively more difficult to flow in the second area. By reasonably selecting and designing the difference between the contact angle of the first area and the contact angle of the second area, the electrolyte can be made to flow mainly along the range of the second area or to be mainly concentrated and attached to the surface of the second area. The leaked electrolyte can even be guided to flow mainly along the second area to a certain extent.

[0007] By arranging the electrode terminals and / or pressure relief mechanisms that are easily corroded and difficult to clean in the first area, it is less likely for the electrolyte to be enriched in the first area, and the electrolyte on the first wall can be effectively prevented from flowing to the locations where the electrode terminals and / or the pressure relief mechanisms are located, thereby avoiding contamination and corrosion of the difficult-to-clean locations such as the electrode terminals and / or the pressure relief mechanisms on the first area, thereby protecting important components on the first area.

[0008] Optionally, in some embodiments, the electrode terminal and the pressure relief mechanism are both disposed in the first region.

[0009] In the technical solution of the embodiment of the present application, the electrode terminal and the pressure relief mechanism are both arranged in the first area, and the installation fitting gap between the electrode terminal and the first wall and the installation fitting gap generated between the pressure relief mechanism and the first wall are also located in the first area, which can provide better protection for the electrode terminal and the pressure relief mechanism at the same time, and effectively ensure the normal use and performance of the electrode terminal and the pressure relief mechanism.

[0010] Optionally, in some embodiments, the first region is coated with an electrophobic electrolyte coating.

[0011] In the technical solution of the embodiment of the present application, the technical means to increase the contact angle of the first area is to coat the electrolyte-repellent coating, and at least one of the electrode terminal and the pressure relief mechanism is correspondingly arranged on the electrolyte-repellent coating, that is, by coating the electrolyte-repellent layer on the first area, the contact angle between the first area and the electrolyte is greater than the contact angle between the second area and the electrolyte. In addition, the electrolyte-repellent coating makes the first area have certain electrolyte-repellent properties, and the electrolyte is not easy to enter the first area. The flow rate of the electrolyte dripping or flowing to the first area will also be relatively faster, which can effectively prevent the electrolyte from penetrating the difficult-to-clean positions on the first wall, and to a certain extent protect the difficult-to-clean positions such as gaps and grooves on the first wall.

[0012] Optionally, in some embodiments, the second region is coated with an electrophilic electrolyte coating.

[0013] In the technical solution of the embodiment of the present application, by coating the second area with an electrolyte-philic layer, the contact angle between the second area and the electrolyte is made smaller than the contact angle between the first area and the electrolyte, and at the same time, the second area has certain electrolyte-philic properties, which can slow down the flow of the electrolyte on the second area, so that the electrolyte is mainly concentrated in the second area, effectively avoiding the electrolyte on the second area from flowing around, and facilitating later cleaning.

[0014] Optionally, in some embodiments, the battery cell further includes a liquid injection hole, which is provided in the second region and is used to inject electrolyte into the housing.

[0015] In the technical solution of the embodiment of the present application, the injection hole is arranged in the second area, so that there is a certain distance between the injection hole and the first area and the important components on the first area. The electrolyte overflowing from the injection hole during the injection process can directly and preferentially contact the outer surface of the second area, the surface energy of the electrolyte flowing in the second area is greater, and the electrolyte is relatively difficult to flow, so that the electrolyte is mainly concentrated in the second area, which is convenient for later cleaning, and at the same time, the first area, the important components on the first area and the important parts on the first area can be effectively protected.

[0016] Optionally, in some embodiments, there are multiple first regions, the multiple first regions are arranged at intervals along the first direction, and the second region is arranged between any two adjacent first regions.

[0017] In the technical solution of the embodiment of the present application, on the one hand, by setting the first area in multiple places, the outer surface of the first wall or important components arranged on the first wall, such as electrode terminals, pressure relief mechanisms, etc., can be fully protected. On the other hand, by setting the second area between two adjacent first areas, the electrolyte on the first area can flow to the second area and be mainly concentrated in the second area, which is convenient for subsequent cleaning.

[0018] Optionally, in some embodiments, the plurality of first areas include a first installation area and a second installation area spaced apart along a first direction, and the second area includes a first guide area disposed between the first installation area and the second installation area;

[0019] The electrode terminal includes a first electrode terminal, the first electrode terminal is arranged in the first installation area, and the pressure relief mechanism is arranged in the second installation area.

[0020] In the technical solution of the embodiment of the present application, the contact angle between the first installation area and the electrolyte and the contact angle between the second installation area and the electrolyte are both greater than the contact angle between the first guide area and the electrolyte. The electrolyte on the first area can flow to the second area and be mainly concentrated in the second area, which is convenient for subsequent cleaning. The first installation area protects the first electrode terminal and the part of the first wall corresponding to the first electrode terminal, and the second installation area protects the pressure relief mechanism and the part of the first wall corresponding to the location where the pressure relief mechanism is set.

[0021] Optionally, in some embodiments, the first area further includes a third installation area, and along the first direction, the third installation area and the second installation area are arranged at intervals; the second area further includes a second guide area arranged between the second installation area and the third installation area;

[0022] The electrode terminal further includes a second electrode terminal, and the second electrode terminal is disposed in the third mounting area.

[0023] In the technical solution of the embodiment of the present application, the first installation area, the second installation area and the third installation area are arranged at intervals along the first direction, and the first electrode terminal, the pressure relief mechanism and the second electrode terminal are also arranged at intervals along the first direction, thereby dispersing the important parts susceptible to corrosion. The first guide area and the second guide area are used to centrally carry the electrolyte to form a buffer area with higher surface energy and smaller contact angle between the first installation area and the second installation area and between the second installation area and the third installation area, effectively slowing down the flow of the electrolyte and guiding the flow direction of the electrolyte.

[0024] Optionally, in some embodiments, the first mounting area, the second mounting area and the third mounting area are all coated with an electrophobic electrolyte coating.

[0025] In the technical solution of the embodiment of the present application, the contact angles of the first installation area, the second installation area, and the third installation area are all greater than the contact angles of the first guide area and the second guide area by coating an electrolyte-repelling coating. And compared with the first guide area and the second guide area, the first installation area, the second installation area, and the third installation area have electrolyte-repelling properties or have better electrolyte-repelling properties, and the electrolyte is more likely to flow quickly through the surfaces of the first installation area, the second installation area, and the third installation area, and is more likely to gather in the first guide area and the second guide area with higher surface energy, thereby forming a channel for easy electrolyte flow in the first guide area and the second guide area, guiding the flow direction of the electrolyte, and facilitating cleaning.

[0026] Optionally, in some embodiments, the battery cell further includes a liquid injection hole, and the liquid injection hole is disposed in the first guide area.

[0027] In the technical solution of the embodiment of the present application, the injection hole is arranged in the first flow guide area, so that the injection hole is spaced a certain distance from the first electrode terminal and the pressure relief mechanism. The electrolyte overflowing from the injection hole during the injection process can directly and preferentially contact the outer surface of the first flow guide area, the surface energy of the electrolyte flowing in the first flow guide area is greater, and the electrolyte is relatively difficult to flow, so that the electrolyte is mainly concentrated in the first flow guide area, which is convenient for later cleaning, and can effectively protect the first electrode terminal and the pressure relief mechanism.

[0028] Optionally, in some embodiments, the first flow guide area is coated with an electrophilic electrolyte coating.

[0029] In the technical solution of the embodiment of the present application, an electrolyte-philic coating is coated on the first guide area so that the contact angle between the first guide area and the electrolyte is smaller than the contact angle between the adjacent first installation area and the second installation area and the electrolyte. At the same time, the electrolyte-philic coating makes the first guide area hydrophilic, or the electrolyte-philic coating makes the first guide area more hydrophilic than the adjacent first installation area and the second installation area, thereby making the surface energy of the electrolyte flowing in the first guide area larger and the electrolyte relatively difficult to flow.

[0030] Optionally, in some embodiments, the shell further includes a second wall, which is disposed adjacent to the first wall; the electrophilic electrolyte coating includes a first part and a second part which are disposed continuously, the first part is coated on the first guide area, and the second part is coated on the outer surface of the second wall.

[0031] In the technical solution of the embodiment of the present application, by coating the second part of the electrophilic electrolyte coating on the second wall, at least part of the second wall is made hydrophilic, and the electrophilic electrolyte coating of the second part is connected to the electrophilic electrolyte coating of the first part located on the first guide area. When the electrolyte on the first wall flows to the second wall, the second part of the electrophilic electrolyte coating located on the second wall also has the effect of slowing down the flow rate of the electrolyte and guiding the flow direction of the electrolyte to a certain extent, which is beneficial to the concentration and cleaning of the electrolyte.

[0032] Optionally, in some embodiments, in the thickness direction of the first wall, the second portion has a first end close to the first portion and a second end away from the first portion, and the width of the second portion gradually increases from the first end to the second end.

[0033] In the technical solution of the embodiment of the present application, the second part is a variable-size structure along the direction from the first end to the second end, and the width of the second part gradually increases, so that the second part can better and more smoothly drain the electrolyte to a position that is easy to clean, so as to keep the electrolyte away from difficult-to-clean gaps, grooves and important parts that are susceptible to corrosion as much as possible, making it easy to clean later and protect the battery cells.

[0034] Optionally, in some embodiments, the housing includes a shell and an end cover, the shell has an opening, the end cover is connected to the shell to seal the opening, and the end cover is the first wall.

[0035] In the technical solution of the embodiment of the present application, the end cover of the outer shell is selected as the first wall, that is, a first area and a second area with different contact angles with the electrolyte are arranged on the end cover, and the flow of the electrolyte on the end cover is a flow in the horizontal plane direction, which can improve the protection effect of the electrode terminals and / or the pressure relief mechanism on the first area, and can be applicable to one or more conventional layout schemes of the electrode terminals and the pressure relief mechanism in the related art.

[0036] In a second aspect, the present application provides a battery, which includes the battery cell in the above embodiment.

[0037] In a third aspect, the present application provides an electrical device, which includes the battery cell in the above embodiment and / or the battery in the above embodiment, and the battery cell and / or the battery are used to provide electrical energy.

[0038] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0041] Figure 2 An exploded view of a battery provided for some embodiments of the present application;

[0042] Figure 3 An exploded schematic diagram of a battery cell provided in some embodiments of the present application;

[0043] Figure 4 A top view of a battery cell provided for some embodiments of the present application (a first area in the figure is shown in a hatched manner);

[0044] Figure 5 A schematic diagram of the definition of the contact angle between the first wall of a battery cell and an electrolyte provided in some embodiments of the present application;

[0045] Figure 6 A three-dimensional schematic diagram of a battery cell provided in some embodiments of the present application;

[0046] Figure 7 for Figure 6 A schematic top view of a battery cell;

[0047] Figure 8 A three-dimensional schematic diagram of a battery cell provided in some other embodiments of the present application;

[0048] Fig. 9 for Figure 8 A schematic top view of a battery cell;

[0049] Fig.10 for Figure 8 Schematic perspective views of battery cells according to some other embodiments of the battery cells.

[0050] Icon: 1000-vehicle; 100-battery; 200-motor; 300-controller; 10-box, 11-first part, 12-second part;

[0051] 20-battery monomer; 21-housing; 22-end cover, 221-first area, 2211-first installation area, 2212-second installation area, 2213-third installation area, 222-second area, 2221-first flow guide area, 2222-second flow guide area; 23-housing, 231-first side wall, 232-second side wall; 24-electrode terminal, 241-first electrode terminal, 242-second electrode terminal; 25-pressure relief mechanism; 26-cell assembly; 27-liquid injection hole; 28-identification code; 291-first part, 292-second part;

[0052] 30-electrolyte-repellent coating; 40-electrolyte-repellent coating. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0055] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0056] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0058] The term "multiple" as used in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple sheets" refers to more than two sheets (including two sheets).

[0059] In this application, the battery mentioned herein refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack, etc.

[0060] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0061] For battery cells, the electrolyte may leak or overflow during the manufacturing process, such as leakage or overflow during injection, or electrolyte overflow during negative pressure formation of the battery cell. The electrolyte adheres to the outer shell, and the electrolyte attached to the surface of the outer shell needs to be cleaned in subsequent processes to minimize the corrosion of the outer shell and important components installed on the outer shell. In addition, since the installation of electrode terminals, pressure relief mechanisms and other parts on the outer shell may have gaps, grooves and other structures that are easy to accumulate electrolytes, if the electrolyte enters these difficult-to-clean structures, it may cause the corresponding structures and components to be corroded to varying degrees, affecting the appearance, and may also cause battery cell safety accidents.

[0062] Based on the above considerations, in order to solve a series of problems such as corrosion of battery cells caused by leakage, overflow and penetration of electrolyte into difficult-to-clean areas, the inventors have designed a battery cell after in-depth research, including a shell, an electrode terminal and a pressure relief mechanism, the shell having a first wall, the outer surface of the first wall including a first area and a second area, the contact angle between the first area and the electrolyte is greater than the contact angle between the second area and the electrolyte; at least one of the electrode terminal and the pressure relief mechanism is arranged in the first area.

[0063] In such a battery cell, two first regions and second regions with different contact angles are arranged on the first wall, so that the flow characteristics of the electrolyte on the first wall are different. Specifically, the surface energy of the electrolyte in the first region is lower and the flow rate is faster, while the surface energy of the electrolyte in the second region is higher and the flow rate is slower, and the electrolyte is relatively less likely to flow in the second region. Compared with the solutions in the related art, on the one hand, the electrode terminals and / or pressure relief mechanisms that are easily corroded and difficult to clean can be selectively arranged in the first region according to actual needs, which can protect the grooves or gaps at the assembly positions of the pressure relief mechanism and / or the electrode terminals and the first wall, thereby protecting the pressure relief mechanism and / or the electrode terminals. On the other hand, by reasonably designing the size and difference of the contact angles of the first region and the second region, the leaked electrolyte can also be guided to flow mainly along the second region, thereby avoiding pollution, corrosion and subsequent safety problems in the difficult-to-clean locations corresponding to the electrode terminals and / or the pressure relief mechanism on the first region.

[0064] The battery cells disclosed in the embodiments of the present application can be used in, but not limited to, electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery cells and batteries disclosed in the present application can be used to form the electrical device, which is beneficial to improving the safety of the battery cells and facilitating the promotion of the battery.

[0065] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0066] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0067] Please refer to Figure 1 , Figure 1A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 300 and a motor 200, and the controller 300 is used to control the battery 100 to power the motor 200, for example, for starting, navigating and driving the vehicle 1000.

[0068] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0069] Please refer to Figure 2 , Figure 2 An exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a box body 10 and a battery cell 20, and the battery cell 20 is contained in the box body 10. Among them, the box body 10 is used to provide a storage space for the battery cell 20, and the box body 10 can adopt a variety of structures. In some embodiments, the box body 10 may include a first part 11 and a second part 12, and the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20. The second part 12 may be a hollow structure with one end open, and the first part 11 may be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 may also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box body 10 formed by the first part 11 and the second part 12 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0070] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0071] Each battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0072] Please refer to Figure 3 , Figure 3 The schematic diagram of the exploded structure of the battery cell 20 provided in some embodiments of the present application. The battery cell 20 refers to the smallest unit constituting the battery 100. Figure 3 The battery cell 20 includes an end cover 22, a shell 23, a battery cell assembly 26, a switching plate and other functional components.

[0073] The end cap 22 refers to a component that covers the opening of the shell 23 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 22 can be adapted to the shape of the shell 23 to match the shell 23. Optionally, the end cap 22 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 22 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 24 can be provided on the end cap 22. The electrode terminal 24 can be used to electrically connect to the battery cell assembly 26 for outputting or inputting electrical energy of the battery cell 20. In some embodiments, the end cap 22 can also be provided with a pressure relief mechanism 25 for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. In some embodiments, the end cap 22 can also be provided with an injection hole for injecting electrolyte into the shell. The material of the end cap 22 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the present embodiment. In some embodiments, an insulating member can be provided on the inner side of the end cap 22, and the insulating member can be used to isolate the electrical connection components in the housing 23 from the end cap 22 to reduce the risk of short circuit. Exemplarily, the insulating member can be plastic, rubber, etc.

[0074] The shell 23 is a component used to cooperate with the end cap 22 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the battery cell assembly 26, electrolyte and other components. The shell 23 and the end cap 22 can be independent components, and an opening can be set on the shell 23, and the internal environment of the battery cell 20 is formed by covering the opening with the end cap 22 at the opening. Without limitation, the end cap 22 and the shell 23 can also be integrated. Specifically, the end cap 22 and the shell 23 can form a common connection surface before other components are put into the shell, and when the interior of the shell 23 needs to be encapsulated, the end cap 22 covers the shell 23. The shell 23 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 23 can be determined according to the specific shape and size of the battery cell assembly 26. The material of the shell 23 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0075] The cell assembly 26 is a component in the battery cell 20 where electrochemical reactions occur. The adapter is a component in the battery cell 20 that transmits current. One or more cell assemblies 26 may be included in the housing 23. The cell assembly 26 is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and a diaphragm is usually provided between the positive electrode sheet and the negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the main body of the cell assembly 26, and the parts of the positive electrode sheet and the negative electrode sheet without active materials are each provided with a pole ear. The positive pole ear and the negative pole ear may be located together at one end of the main body or respectively at both ends of the main body. During the charging and discharging process of the battery 100, the positive active material and the negative active material react with the electrolyte, and the adapter is connected between the pole ear and the electrode terminal 24 to form a current loop.

[0076] According to some embodiments of the present application, Figure 3 to Figure 7 As shown, the present application provides a battery cell 20, which includes a pressure relief mechanism 25. The pressure relief mechanism 25 is a functional component for timely releasing the internal pressure of the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a threshold value.

[0077] The number of the pressure relief mechanism 25 may be one, or two or more, and may be set according to actual needs.

[0078] The battery cell 20 further includes an electrode terminal 24 , which is a functional component that can be used to be electrically connected to the battery cell assembly 26 to output or input electrical energy of the battery cell 20 .

[0079] Likewise, the number of the electrode terminals 24 may be one or two, which may be adaptively adjusted according to the type and specific structure of the battery cell 20 .

[0080] The battery cell 20 also includes a shell 21, which has a first wall. The outer surface of the first wall includes a first area 221 and a second area 222, and the contact angle between the first area 221 and the electrolyte is greater than the contact angle between the second area 222 and the electrolyte; at least one of the electrode terminal 24 and the pressure relief mechanism 25 is arranged in the first area 221.

[0081] The shell 21 has a receiving cavity for accommodating the battery cell assembly 26, the electrolyte and other components. The shell 21 has a certain hardness and strength. The shell 21 is not easy to deform when it is squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. In some embodiments. The first area 221 and the second area 222 can be arranged at intervals. In some embodiments, the ends of the first area 221 and the second area 222 that are close to each other can also be at least partially connected. In some embodiments, the first area 221 and the second area 222 can both be composed of a continuous area or a plurality of spaced partitions. The outer surface of the first wall, the outer surface of the second wall, the outer surface of the shell 21, etc. mentioned herein all refer to the end face of the corresponding shell wall that is away from the receiving cavity of the shell 21 in the thickness direction and is spaced from the receiving cavity.

[0082] The contact angle, also known as the wetting angle, refers to the angle between the solid-liquid interface, the liquid interior and the gas-liquid interface at the interface of solid, liquid and gas. It reflects the degree of wetting of the solid by the liquid and is a quantitative measure of surface wettability. For example, a drop of water will wet and spread on a clean glass; while a drop of water will remain in a water drop state on a waxy surface and will not wet. Wetting and non-wetting are not polar relationships but a quantifiable quantity. The parameter index for quantifying the degree of wetting is the wetting angle / contact angle.

[0083] like Figure 5 As shown in the figure, the contact angle θ of the liquid on the solid surface is related to the free energy Y of the solid-gas interface SV , solid-liquid interface free energy Y SL and the surface tension Y of the liquid LV The relationship between them obeys Young's wetting equation: SV =Y SL +Y LV×cosθ, this equation can be regarded as the result of the balance between the three interfacial tensions at the junction of solid, liquid and gas phases. Normally, the contact angle can be measured using a so-called goniometer, such as a static contact angle meter SZ-CAMA1, after the electrolyte droplets are placed in the first area 221 and the second area 222, and then measured respectively. Generally, when the contact angle θ>90°, the liquid will be in a contracted state on the solid surface, and the solid surface at this time is defined as a lyophobic surface. When the contact angle θ>150°, the solid surface is called a super-phobic electrolyte surface. When the contact angle θ=180°, the solid surface is a completely lyophobic electrolyte surface. When the contact angle θ<90°, the liquid will be in an expanded state on the solid surface, wetting the solid surface to a certain extent, and the solid surface at this time is defined as a lyophilic surface.

[0084] For example, after the pressure relief mechanism 25 is assembled, a groove or gap will be formed between it and the shell wall of the corresponding shell 21 , and after the electrode terminal 24 is assembled, a groove or gap will also be formed between it and the shell wall of the corresponding shell 21 .

[0085] In the technical solution of the embodiment of the present application, by setting two first areas 221 and second areas 222 with different contact angles on the first wall, the flow characteristics of the electrolyte on the first wall are different. Specifically, the surface energy of the electrolyte in the first area 221 is lower and the flow rate is faster, while the surface energy of the electrolyte in the second area 222 is higher and the flow rate is slower. The electrolyte is relatively more difficult to flow in the second area 222. By reasonably selecting and designing the difference between the contact angle of the first area 221 and the contact angle of the second area 222, the electrolyte can be made to flow mainly along the range of the second area 222 or to be mainly concentrated and attached to the surface of the second area 222. The leaked electrolyte can even be guided to flow mainly along the second area 222 to a certain extent.

[0086] Therefore, the electrolyte is not easily attached to the first area 221, or even if the electrolyte drops on the first area 221, the electrolyte can quickly slide away from the first area 221 and flow to and adhere to the second area 222 having a smaller contact angle with the electrolyte.

[0087] By arranging the electrode terminals 24 and / or the pressure relief mechanism 25 which are easily corroded and difficult to clean in the first area 221, it is made less likely for the electrolyte to be enriched in the first area 221, and the electrolyte on the first wall can be effectively prevented from flowing to the locations where the electrode terminals 24 and / or the pressure relief mechanism 25 are located, thereby avoiding contamination and corrosion of the grooves, gaps and other locations which are difficult to clean corresponding to the electrode terminals 24 and / or the pressure relief mechanism 25 on the first area 221, thereby protecting the important components on the first wall.

[0088] Compared with the solutions in the related art, on the one hand, by setting the electrode terminal 24 and / or the pressure relief mechanism 25 which are easily corroded and difficult to clean in the first area 221, the electrolyte is less likely to be enriched in the first area 221; on the other hand, by reasonably designing the size and difference of the contact angles between the first area 221 and the second area 222, the leaked electrolyte can also be guided to flow mainly along the second area 222, thereby avoiding contamination and corrosion of the difficult-to-clean positions corresponding to the electrode terminal 24 and / or the pressure relief mechanism 25 on the first area 221. The electrolyte can be protected from accumulating in the groove or gap at the assembly position of the pressure relief mechanism 25 and / or the electrode terminal 24 and the first wall, which plays the effect of protecting the pressure relief mechanism 25 and / or the electrode terminal 24, and effectively alleviates the corrosion problem caused by electrolyte deposition and difficulty in cleaning and the problem of subsequent safety in use.

[0089] In some embodiments, at least one of the pressure relief mechanism 25 and the electrode terminal 24 is disposed on the first wall, that is, in some embodiments, the pressure relief mechanism 25 and the electrode terminal 24 can be disposed on different shell walls, and in some embodiments, the pressure relief mechanism 25 and the electrode terminal 24 can also be disposed on the first wall at the same time. And when the pressure relief mechanism 25 and the electrode terminal 24 are both disposed on the first wall, at least one of the pressure relief mechanism 25 and the electrode terminal 24 can also be selectively disposed in the first area 221 according to the actual structure and layout scheme, so as to give priority to protecting the important functional components located in the first area 221.

[0090] According to some embodiments of the present application, optionally, the electrode terminal 24 and the pressure relief mechanism 25 are both disposed in the first region 221 .

[0091] In the conventional manufacturing scheme of battery cells 20, there are gaps or grooves at the positions corresponding to the electrode terminals 24, the terminal base, and the pressure relief mechanism 25. Once the electrolyte enters, it is difficult to completely clean it, resulting in poor appearance and even corrosion. The electrode terminals 24 and the pressure relief mechanism 25 are important functional components of the battery cells 20. The electrode terminals 24 and the pressure relief mechanism 25 are easily corroded by the electrolyte, which may affect the input and output of the electric energy of the battery cells 20. If the pressure relief mechanism 25 cannot be used normally, it may cause thermal runaway and other problems. Therefore, it is important to effectively protect the electrode terminals 24 and the pressure relief mechanism 25 from being corroded by the electrolyte during the manufacturing process of the battery cells 20, which is conducive to improving the safety performance of the battery cells 20.

[0092] By arranging both the electrode terminal 24 and the pressure relief mechanism 25 in the first area 221, the installation fitting gap between the electrode terminal 24 and the first wall and the installation fitting gap generated between the pressure relief mechanism 25 and the first wall are also located in the first area 221, which can provide better protection for the electrode terminal 24 and the pressure relief mechanism 25 at the same time, and effectively ensure the normal use and performance of the electrode terminal 24 and the pressure relief mechanism 25.

[0093] In some embodiments, in order to further protect the electrode terminals 24 and the pressure relief mechanism 25 on the first region 221, the electrode terminals 24 and the pressure relief mechanism 25 can be set to be spaced apart from the second region 222, that is, there is also a certain distance between the boundary line of the second region 222 close to the electrode terminal 24 / pressure relief mechanism 25 and the periphery of the corresponding electrode terminal 24 / pressure relief mechanism 25, so as to effectively reduce the risk of the slower-flowing electrolyte gathered at the edge of the second region 222 directly contacting the electrode terminal 24 and the pressure relief mechanism 25.

[0094] The present application does not limit the specific means for realizing the technical effect of "the contact angle between the first region 221 and the electrolyte is greater than the contact angle between the second region 222 and the electrolyte". For example, in some embodiments, at least one of the first region 221 and the second region 222 can be obtained by surface treatment on the outer surface of the first wall. There are many factors that affect the size of the contact angle. On the one hand, the surface roughness of the solid is also one of the factors that affect the contact angle. When the solid surface is rough, the contact angle of the liquid on the solid surface usually becomes larger. The rough surface increases the contact area between the liquid and the solid, making it more difficult for the liquid to spread on the solid surface. Therefore, in some embodiments, the surface of the first region 221 and / or the second region 222 can be roughened by increasing the roughness of the first region 221, and the roughness of the first region 221 is greater than the roughness of the second region 222, so that the contact angle between the first region 221 and the electrolyte is greater than the contact angle between the second region 222 and the electrolyte.

[0095] On the other hand, the properties of the liquid and the solid are important factors that affect the contact angle. Specifically, the surface tension of the liquid determines the extent to which the liquid spreads on the solid surface. The greater the surface tension, the smaller the contact angle of the liquid on the solid surface. In addition, the viscosity and density of the liquid will also affect the size of the contact angle. The surface properties of the solid will also affect the contact angle, such as the chemical composition and surface energy of the solid surface.

[0096] In order to make the surface characteristics of the first region 221 and the second region 222 in contact with the electrolyte have a more obvious difference or gradient, so as to provide a better effect of protecting the first region 221, in some embodiments, the contact angle between the first region 221 and the electrolyte is θ1, and the contact angle between the second region 222 and the electrolyte is θ2, which satisfies: 80°≤θ1≤160°, 20°≤θ2≤100°, and θ1>θ2 at the same time. For example, θ1 can be 80°, 90°, 100°, 105°, 120°, 140°, 155°, 160°, etc. θ2 can be 20°, 30°, 45°, 55°, 60°, 80°, 95°, 100°, etc.

[0097] When the contact angle θ1 between the first region 221 and the electrolyte satisfies 80°≤θ1≤160°, the first region 221 can have certain electrolyte repellency characteristics in most settings, and the larger θ1 is, the less likely the electrolyte will gather and stay in the first region 221. When the contact angle θ1 between the first region 221 and the electrolyte satisfies the above range, it is ensured that the first region 221 has sufficient hydrophobicity, and at the same time, it will not cause the first region 221 to be processed more difficultly due to the excessively large contact angle between the first region 221 and the electrolyte, or cause the problem of higher cost due to overly stringent quality requirements for the coating disposed in the first region 221.

[0098] Similarly, the contact angle θ2 between the second region 222 and the electrolyte satisfies the above range, which not only ensures that the second region 222 has sufficient hydrophilicity, but also reduces the processing difficulty of the second region 222 or reduces the cost of the coating on the second region 222.

[0099] The main optional situation of the second region is also to have certain electrophilic properties. In most cases, there can be an obvious contact angle gradient difference between the first region 221 and the second region 222, which can improve the protection effect of the first region 221 while taking into account the difficulty of the molding and manufacturing process of the first region 221 and the second region 222. Only when θ1 and θ2 are both selected in the range of 80° to 100°, there may be a situation where the difference between the two contact angles is small, but as long as adaptive adjustments are made according to the distribution of different battery cell types and functional components of different battery cells, so that the contact angles of the first region and the second region can achieve a certain protection effect, at this time, when θ1 and θ2 are both between 80° and 100°, the manufacturing difficulty of the second region 222 and the first region 221 is greatly reduced, which is conducive to controlling production costs.

[0100] According to some embodiments of the present application, optionally, the first region 221 is coated with an electrolyte-repellent coating 30 .

[0101] Similarly, when the contact angle θ between the coating and the electrolyte is greater than 90°, the coating is positioned as an electrolyte-repellent coating 30, and the electrolyte shrinks on the electrolyte-repellent coating 30. The larger the contact angle between the electrolyte and the electrolyte-repellent coating 30, the shorter the time the electrolyte can stay in the electrolyte-repellent coating 30, and the less corrosion the electrolyte causes to the electrolyte-repellent coating 30.

[0102] In some embodiments, the electrophobic electrolyte coating 30 may be mainly composed of fluorine-containing long-chain silane and other low surface energy substances, and the electrophobic electrolyte coating 30 has the characteristics of a large contact angle and low surface energy.

[0103] That is to say, the technical means to increase the contact angle of the first area 221 is to coat the electrolyte-repellent coating 30, and at least one of the electrode terminal 24 and the pressure relief mechanism 25 is correspondingly arranged on the electrolyte-repellent coating 30, that is to say, by coating the electrolyte-repellent layer on the first area 221, the contact angle between the first area 221 and the electrolyte is greater than the contact angle between the second area 222 and the electrolyte. In addition, the electrolyte-repellent coating 30 makes the first area 221 have certain electrolyte-repellent properties, and the electrolyte is not easy to enter the first area 221. The flow rate of the electrolyte dripping or flowing to the first area 221 will also be relatively faster, which can effectively prevent the electrolyte from penetrating the difficult-to-clean positions on the first wall, and to a certain extent protect the difficult-to-clean positions such as gaps and grooves on the first wall. In some embodiments, the contact angle between the electrolyte-repellent coating 30 and the electrolyte is the contact angle θ1 between the first region 221 and the electrolyte, which satisfies: 140°≤θ1≤160°, for example, the contact angle θ1 of the electrolyte-repellent coating 30 may be 140°, 145°, 152°, 155°, 160°, etc. On the one hand, it can ensure that the liquid is not easy to adhere to the first region 221, and on the other hand, it can effectively avoid the problem of too stringent requirements on the quality of the coating due to too large a contact angle, thereby reducing production costs.

[0104] Optionally, in some embodiments, the second region 222 is coated with an electrophilic electrolyte coating 40 .

[0105] Generally, when the contact angle θ is less than 90°, the liquid will be in an extended state on the solid surface and will infiltrate the solid surface to a certain extent. At this time, the solid surface is defined as a lyophilic surface. Similarly, when the contact angle θ between the coating and the electrolyte is less than 90°, the coating is positioned as an electrophilic electrolyte coating 40, and the electrolyte is extended on the electrophilic electrolyte coating 40. The smaller the contact angle between the electrolyte and the electrophobic electrolyte coating 30, the longer the electrolyte can stay on the electrophobic electrolyte coating 30 and the less likely it is to flow.

[0106] In some embodiments, the electrophilic electrolyte coating 40 may be mainly composed of polyvinyl alcohol and natural phosphate earth minerals, etc. The contact angle between the electrophilic electrolyte coating 40 and the electrolyte is small and the surface energy is high, which can effectively slow down the flow of the electrolyte. The second area 222 is coated with the electrophilic electrolyte coating 40, which can further concentrate the electrolyte in the second area 222, and is less likely to flow to the first area 221 and the difficult-to-clean position on the first area 221.

[0107] That is to say, by coating the second region 222 with an electrolyte-philic layer, the contact angle between the second region 222 and the electrolyte is made smaller than the contact angle between the first region 221 and the electrolyte, and at the same time, the second region 222 has certain electrolyte-philic properties, which can slow down the flow of the electrolyte on the second region 222, so that the electrolyte is mainly concentrated in the second region 222, effectively preventing the electrolyte on the second region 222 from flowing around, and facilitating later cleaning.

[0108] In some embodiments, the contact angle of the electrophilic electrolyte coating 40 is denoted as θ 21 , optionally, θ 21 The selection range can be 20°≤θ 21 ≤40°, for example, θ 21 It can be 20°, 24°, 28°, 30°, 35°, 38°, 40°, etc. On the one hand, it can ensure that the liquid is easily attached to the second area 222, and on the other hand, it can effectively avoid the problem of too stringent requirements on the quality of the coating due to too small a contact angle, thereby reducing production costs.

[0109] Optionally, in some embodiments, the battery cell 20 further includes a liquid injection hole 27 , which is disposed in the second region 222 and is used to inject electrolyte into the housing 21 .

[0110] The injection hole 27 is a functional component that connects the housing 21 to the outside. In the injection step, the electrolyte is injected into the housing 21 through the injection hole 27. Due to the structure, size, and injection rate of the injection hole 27, the electrolyte may overflow from the injection hole 27 and flow onto the corresponding housing wall during the injection process. In some embodiments, the injection hole 27 may be provided on a housing wall other than the first wall of the housing 21.

[0111] The injection hole 27 is arranged in the second area 222, that is, on the first wall, which conforms to the layout of the common arrangement scheme in the related art, and makes a certain distance between the injection hole 27 and the first area 221 and the important components on the first area 221. The electrolyte overflowing from the injection hole 27 during the injection process can directly and preferentially contact the outer surface of the second area 222, and the surface energy of the electrolyte flowing in the second area 222 is greater, and the electrolyte is relatively difficult to flow, so that the electrolyte is mainly concentrated in the second area 222, which is convenient for later cleaning, and can effectively protect the first area 221, the important components on the first area 221, and the important parts on the first area 221.

[0112] In some embodiments, in order to further protect important functional components disposed on the first region 221 , the injection hole 27 may be spaced apart from the first region 221 , that is, there is also a certain distance between the boundary line of the first region 221 close to the injection hole 27 and the injection hole 27 .

[0113] Optionally, in some embodiments, there are multiple first regions 221 , and the multiple first regions 221 are arranged at intervals along the first direction, and a second region 222 is provided between any two adjacent first regions 221 .

[0114] like Figure 3 As shown, the first direction refers to the length direction of the battery cell 20 ( Figure 3 In the Y direction), the first area 221 is configured to be multiple and spaced apart along the first direction, that is, the multiple first areas 221 are discontinuous and not connected, which can meet the requirements of dispersed layout of important components, and at the same time increase the setting area of ​​the second area 222, thereby improving the probability and effect of effective protection.

[0115] On the one hand, by providing multiple first regions 221, the outer surface of the first wall or important components provided on the first wall, such as the electrode terminal 24, the pressure relief mechanism 25, etc., can be fully protected. On the other hand, by providing the second region 222 between two adjacent first regions 221, the electrolyte on the two adjacent first regions 221 can flow to the second region 222 and be mainly concentrated in the second region 222, which is convenient for subsequent cleaning.

[0116] Optionally, in some embodiments, the plurality of first regions 221 include a first installation region 2211 and a second installation region 2212 spaced apart along the first direction, and the second region 222 includes a first guide region 2221 disposed between the first installation region 2211 and the second installation region 2212;

[0117] The electrode terminal 24 includes a first electrode terminal 241 . The first electrode terminal 241 is disposed in the first installation area 2211 . The pressure relief mechanism 25 is disposed in the second installation area 2212 .

[0118] The shape of the first installation area 2211 can be regular or irregular, and similarly, the shape of the second installation area 2212 can be regular or irregular. In some embodiments, the shape of the first installation area 2211 and the shape of the second installation area 2212 can be the same or different.

[0119] In some embodiments, the battery cell 20 may have only a first electrode terminal 241, for example, another electrode output terminal is directly integrated on the outer shell 21 after the battery cell 20 is formed, and one of the shell walls of the outer shell 21 is directly electrically connected to the battery cell assembly 26 for outputting or inputting electrical energy of the battery cell 20.

[0120] In some embodiments, the contact angle setting of the first mounting area 2211 and the second mounting area 2212 can be achieved by applying a chemical coating, or by surface roughening treatment, or by applying a chemical coating and then roughening the surface of the chemical coating.

[0121] By setting the contact angle between the first installation area 2211 and the electrolyte and the contact angle between the second installation area 2212 and the electrolyte to be greater than the contact angle between the first guide area 2221 and the electrolyte, the electrolyte on the first area 221 can flow to the second area 222 and be mainly concentrated in the second area 222, which is convenient for subsequent cleaning. The first installation area 2211 protects the first electrode terminal 241 and the portion of the first wall corresponding to the first electrode terminal 241, and the second installation area 2212 protects the pressure relief mechanism 25 and the portion of the first wall corresponding to the location where the pressure relief mechanism 25 is set.

[0122] As described above, in order to improve the protection of important functional components on the first area 221, the boundary line of the first area 221 can be spaced apart from the injection hole 27, or the functional components can be spaced apart from the boundary line of the first area 221. In the scheme where the first installation area 2211, the first guide area 2221, and the second installation area 2212 are sequentially arranged along the first direction, in order to enhance the protection of the first electrode terminal 241 and the pressure relief mechanism 25, in some embodiments, along the first direction, the first guide area 2221 has a first edge and a second edge, and the first edge can be closer to the first electrode terminal 241 than the second edge. In some embodiments, it can also be set as follows: along the first direction, the shortest distance between the first edge and the first electrode terminal 241 is a, and the shortest distance between the injection hole 27 and the first electrode terminal 241 is b, satisfying: 1 / 3≤a / b≤2 / 3; and / or; along the first direction, the shortest distance between the second edge and the pressure relief mechanism 25 is c, and the shortest distance between the injection hole 27 and the pressure relief mechanism 25 is d, satisfying: 1 / 3≤c / d≤2 / 3, so as to protect the pressure relief mechanism 25 and the first electrode terminal 241 to a certain extent.

[0123] Optionally, in some embodiments, the first area 221 further includes a third installation area 2213, and along the first direction, the third installation area 2213 and the second installation area 2212 are arranged at intervals; the second area 222 further includes a second guide area 2222 arranged between the second installation area 2212 and the third installation area 2213;

[0124] The electrode terminal 24 further includes a second electrode terminal 242 . The second electrode terminal 242 is disposed in the third mounting area 2213 .

[0125] The power input and power output of the battery cell 20 are realized by the cooperation of the first electrode terminal 241 and the second electrode terminal 242 , which is simpler and safer than the solution in which the second electrode terminal 242 is integrated in the housing 21 .

[0126] By arranging the first installation area 2211, the second installation area 2212 and the third installation area 2213 at intervals along the first direction, the first electrode terminal 241, the pressure relief mechanism 25 and the second electrode terminal 242 are also arranged at intervals along the first direction, thereby dispersing the important parts susceptible to corrosion. The first guide area 2221 and the second guide area 2222 are used to centrally carry the electrolyte, so as to form a buffer area with higher surface energy and smaller contact angle between the first installation area 2211 and the second installation area 2212 and between the second installation area 2212 and the third installation area 2213, effectively slowing down the flow of the electrolyte and guiding the flow direction of the electrolyte.

[0127] In some embodiments, the contact angle setting of the third mounting area 2213 can be achieved by applying a chemical coating, or by surface roughening treatment, or by applying a chemical coating and then roughening the surface of the chemical coating.

[0128] Optionally, in some embodiments, the first installation area 2211 , the second installation area 2212 , and the third installation area 2213 are all coated with an electrolyte-repellent coating 30 .

[0129] The electrolyte repellent coating 30 can provide a larger optional range for the contact angles of the first mounting area 2211, the second mounting area 2212, and the third mounting area 2213. In addition, since the composition characteristics of the electrolyte are easy to determine, the material selection and ratio design of the chemical coating can be carried out in a targeted and directional manner, which can provide a more stable and reliable electrolyte repellent effect. In some embodiments, the contact angles of the first mounting area 2211, the second mounting area 2212, and the third mounting area 2213 can be the same or different.

[0130] The contact angles of the first installation area 2211, the second installation area 2212 and the third installation area 2213 are all greater than the contact angles of the first guide area 2221 and the second guide area 2222 by coating the electrolyte repellent coating 30. Compared with the first guide area 2221 and the second guide area 2222, the first installation area 2211, the second installation area 2212 and the third installation area 2213 have electrolyte repellent properties or have better electrolyte repellent properties, and the electrolyte is more likely to flow through the surfaces of the first installation area 2211, the second installation area 2212 and the third installation area 2213 more quickly, and is more likely to gather in the first guide area 2221 and the second guide area 2222 with higher surface energy, thereby forming a channel for the electrolyte to flow in the first guide area 2221 and the second guide area 2222, guiding the flow direction of the electrolyte, and facilitating cleaning.

[0131] Optionally, in some embodiments, the battery cell 20 further includes a liquid injection hole 27 , and the liquid injection hole 27 is disposed in the first guide area 2221 .

[0132] The first electrode terminal 241 , the injection hole 27 and the pressure relief mechanism 25 are arranged at intervals along the first direction, and the injection hole 27 is arranged on the first guide area 2221 with a smaller contact angle.

[0133] The injection hole 27 is arranged in the first flow guide area 2221, so that there is a certain distance between the injection hole 27 and the first electrode terminal 241 and the pressure relief mechanism 25. During the injection process, the electrolyte overflowing from the injection hole 27 can directly and preferentially contact the outer surface of the first flow guide area 2221, and the surface energy of the electrolyte flowing in the first flow guide area 2221 is larger, and the electrolyte is relatively difficult to flow, so that the electrolyte is mainly concentrated in the first flow guide area 2221, which is convenient for later cleaning, and can effectively protect the first electrode terminal 241 and the pressure relief mechanism 25.

[0134] Optionally, in some embodiments, the first flow guiding region 2221 is coated with an electrophilic electrolyte coating 40 .

[0135] The optional setting of the electrophilic electrolyte coating 40 can provide the first guide area 2221 and the second area 222 with better electrolyte aggregation and electrolyte flow rate slowing effect. In addition, since the composition characteristics of the electrolyte are easy to determine, the material selection and proportion design of the electrophilic electrolyte coating 40 can be carried out in a targeted and directionally manner, which can provide a more stable and reliable electrophilic electrolyte effect, so that the electrolyte can spread out in the first guide area 2221 and flow slowly. In the technical solution of the embodiment of the present application, by coating the electrophilic coating 40 on the first guide area 2221, the contact angle between the first guide area 2221 and the electrolyte is smaller than the contact angle between the adjacent first installation area 2211 and the second installation area 2212 and the electrolyte. At the same time, the electrophilic coating 40 makes the first guide area 2221 have an electrophilic property, or compared with the adjacent first installation area 2211 and the second installation area 2212, the electrophilic coating 40 makes the first guide area 2221 have better electrophilic properties, thereby making the surface energy of the electrolyte flowing in the first guide area 2221 larger, and the electrolyte is relatively difficult to flow.

[0136] In addition, in some embodiments, if the first guide area 2221 is coated with an electrophobic electrolyte coating 30 and then coated with an electrophilic electrolyte coating 40, the gradient difference between the contact angle of the first region 221 and the contact angle of the first guide area 2221 can be significantly increased.

[0137] In some embodiments, the second guide region 2222 may be coated with the electrophilic electrolyte coating 40 or may not be coated with the electrophilic electrolyte coating 40, as long as the contact angle between the second guide region 2222 and the electrolyte is smaller than the contact angle between the first region 221 and the electrolyte.

[0138] In some embodiments, the first guide region 2221 is coated with an electrophilic coating 40, and the contact angles of the second guide region 2222 and the first guide region 2221 may be different. For example, the contact angle of the first guide region 2221 is θ 21 , the contact angle of the second flow guiding area 2222 is θ 22 , satisfying: 20°≤θ 21 ≤40°, 80°≤θ 22≤100°. On the one hand, it can ensure that the flow characteristics of the electrolyte in the first guide area 2221 and the second guide area 2222 have certain differences, so that the electrolyte overflowing from the injection hole can be mainly gathered in the first guide area 2221, which can reduce the impact on the first electrode terminal 241 and the pressure relief mechanism 25. Since there is no injection hole 27 on the second guide area 2222, the electrolyte that may drip on the second guide area 2222 is less than the electrolyte in the first guide area 2221, so the second guide area 2222 has lower requirements for electrolyte adsorption and diversion. Therefore, on the basis of ensuring that the contact angle of the second guide area 2222 is smaller than the contact angle of the first area 221, the contact angle of the second guide area 2222 can be set larger, effectively avoiding the problem of too high requirements on the polishing process of the surface of the second guide area 2222 or too stringent requirements on the quality of the coating due to too large or too small contact angle, thereby reducing production costs.

[0139] Optionally, in some embodiments, the housing 21 further includes a second wall, which is disposed adjacent to the first wall; the electrophilic electrolyte coating 40 includes a first portion 291 and a second portion 292 which are disposed continuously, the first portion 291 is coated on the first guide area 2221, and the second portion 292 is coated on the outer surface of the second wall.

[0140] The second wall is adjacent to the first wall and is arranged at an angle. The electrolyte-philic coating 40 is simultaneously coated on the first guide area 2221 and at least a portion of the outer surface of the second wall, so that the second wall also has an area that can slow down the flow of electrolyte, which is beneficial to protecting the first wall or other surfaces of the battery cell 20.

[0141] For example, in some embodiments, the first wall and the second wall are continuously arranged along the circumference of the housing 21, that is, the first wall and the second wall are parallel to the height direction of the battery cell 20 ( Figure 3 Z direction in the diagram), the flow of the electrolyte on the first portion 291 and the second portion 292 is slower than that of the electrolyte on the first region 221, thereby increasing the adsorption effect of the electrolyte on the corner portion, and the electrolyte on the first portion 291 and the electrolyte on the second portion 292 can be transferred to each other, and a portion of the electrolyte can be gathered for easy cleaning.

[0142] In some embodiments, one of the first wall and the second wall may be parallel to the height direction of the battery cell 20, and the other may be perpendicular to the height direction of the battery cell 20. For example, in the height direction of the battery cell 20, the first wall may be the bottom wall of the battery cell 20, and the second wall may be a side wall connected to the top of the first wall. The second part 292 of the electrophilic electrolyte coating 40 is provided on the second wall. As long as the contact angle of the second part 292 is reasonable, the electrolyte flowing down from the top of the battery cell 20 can be mainly gathered in the electrophilic electrolyte coating 40 of the second part 292 instead of continuing to flow down, thereby effectively protecting the functional components on the first wall and the second wall.

[0143] In the technical solution of the embodiment of the present application, by coating the second part 292 of the electrolyte-philic coating 40 on the second wall, at least a part of the second wall has an electrolyte-philic property, and the electrolyte-philic coating 40 of the second part 292 is connected to the electrolyte-philic coating 40 of the first part 291 located on the first guide area 2221. When the electrolyte on the first wall flows to the second wall, the second part 292 of the electrolyte-philic coating 40 located on the second wall also has the effect of slowing down the flow rate of the electrolyte and guiding the flow direction of the electrolyte to a certain extent, which is beneficial to the concentration and cleaning of the electrolyte.

[0144] Optionally, in some embodiments, in the thickness direction of the first wall, the second portion 292 has a first end close to the first portion 291 and a second end away from the first portion 291 , and the width of the second portion 292 gradually increases from the first end to the second end.

[0145] like Figure 3 As shown, the Z direction is the thickness direction of the first wall. Along the thickness direction of the first wall, one end surface of the first wall is close to the accommodating cavity of the shell 21, and the other end surface is far away from the accommodating cavity of the shell 21 and is spaced apart from the accommodating cavity.

[0146] Along the direction from the first end to the second end, the second part 292 is a variable size structure, and the width of the second part 292 gradually increases, so that the second part 292 can better and more smoothly drain the electrolyte to a position that is easy to clean, so as to keep the electrolyte away from difficult-to-clean gaps, grooves and important parts that are susceptible to corrosion as much as possible, making it easy to clean later and protect the battery cell 20.

[0147] Optionally, in some embodiments, the housing 21 includes a shell 23 and an end cover 22 , the shell 23 has an opening, the end cover 22 is connected to the shell 23 to seal the opening, and the end cover 22 is a first wall.

[0148] The end cap 22 covers the opening of the shell 23 to isolate the internal environment of the battery cell 20 from the external environment. The shell 21 and the end cap 22 together form a housing cavity for encapsulating the battery cell assembly 26 and other components. The first wall is the end cap 22, and one of the circumferential side walls of the shell 23 is the second wall. As described above, the shell 23 and the end cap 22 can be independent components, or the end cap 22 and the shell 23 can be integrated.

[0149] By setting the end cover 22 as the first wall, at least one of the pressure relief mechanism 25 and the electrode terminal 24 is arranged on the end cover 22, which is a more common arrangement in the relevant technology. In addition, the preparation technology of the outer shell 21 and the arrangement technology of the pressure relief mechanism 25 and the electrode terminal 24 are relatively mature. There is no need to change the assembly process of the battery cell 20, and the production efficiency is high.

[0150] A first region 221 and a second region 222 having different contact angles with the electrolyte are provided on the end cover 22, and the electrolyte flows on the end cover 22 in a horizontal direction, which can improve the protection effect of the electrode terminal 24 and / or the pressure relief mechanism 25 on the first region 221, and can be applicable to one or more conventional layout schemes of the electrode terminal 24 and the pressure relief mechanism 25 in the related art.

[0151] In some embodiments, the outer surface of the first region 221 and the outer surface of the second region 222 may also be set to a non-coplanar structure. Specifically, when the first region 221 and the second region 222 are both coated with a chemical coating, the distance between the surface of the first region 221 for contacting with the electrolyte and the outer surface of the first wall may be greater than the distance between the surface of the second region 222 for contacting with the electrolyte and the outer surface of the first wall, that is, when the outer surface of the first wall is a coplanar structure, the thickness of the chemical coating of the first region 221 is greater than the thickness of the chemical coating on the second region 222, thereby effectively reducing the probability of a large amount of electrolyte accumulated on the second region 222 flowing from the junction of the first region 221 and the second region 222 to the first region 221, thereby improving the protection effect of the first region 221. In some embodiments, an identification code 28 may also be set on the first wall. The identification code 28 is a functional component that provides users with the manufacturing source of the battery cell 20 and specific information of the battery cell 20. The identification code 28 can be selectively set in the first region 221 or the second region 222 according to the actual protection requirements of the identification code 28. In some embodiments, to ensure the integrity of the identification code 28, the identification code 28 can be set in the first area 221. In addition, when the second area 222 includes multiple partitions with different contact angles, the identification code 28 can also be set in a partition among the multiple partitions of the second area 222 that has a larger contact angle and can meet the protection requirements of the identification code 28.

[0152] According to some embodiments of the present application, optionally, the present application further provides a battery 100, which includes the battery cell 20 as described above.

[0153] According to some embodiments of the present application, optionally, the present application further provides an electrical equipment device, which includes the above battery cell 20 and / or the above battery 100, and the battery cell 20 and / or the battery 100 are used to provide electrical energy.

[0154] According to some embodiments of the present application, see Figures 3 to 7 The present application provides a square-structured single battery 100, comprising a housing 21, a first electrode terminal 241, a second electrode terminal 242 and a pressure relief mechanism 25. The housing 21 comprises a shell 23 and an end cap 22, and the first electrode terminal 241, the pressure relief mechanism 25 and the second electrode terminal 242 are arranged along the length direction of the battery cell 20 (i.e., the first direction, i.e., Figure 3 The first mounting area 2211, the first guide area 2221, the second mounting area 2212, the second guide area 2222 and the third mounting area 2213 are arranged in sequence along the first direction on the end cover 22. The second guide area 2222 is also provided with an identification code 28 for users to obtain information such as the source of the battery cell 20. The contact angles between the first mounting area 2211, the second mounting area 2212 and the third mounting area 2213 and the electrolyte are all greater than the contact angles between the first guide area 2221 and the second guide area 2222 and the electrolyte.

[0155] Optionally, the electrolyte-repellent coating 30 is coated only on the first installation area 2211, the second installation area 2212 and the third installation area 2213, and the optional range of the contact angle θ1 between the electrolyte-repellent coating 30 and the electrolyte is 140°≤θ1≤160°. On the one hand, it can ensure that the liquid is not easy to adhere to the first area 221, and on the other hand, it can effectively avoid the problem of overly stringent requirements on the quality of the coating due to excessively large contact angles, thereby reducing production costs.

[0156] Optionally, the electrophilic electrolyte coating 40 is coated only on the first flow guide area 2221, and the contact angle θ between the electrophilic electrolyte coating 40 and the electrolyte is 21 The optional range is 20°≤θ 21 ≤40°. The contact angle of the second flow guiding area 2222 is θ 22 The optional range is 80°≤θ 22 ≤100°, and the contact angles of the first mounting area 2211, the second mounting area 2212 and the third mounting area 2213 are greater than θ 22 .

[0157] Optionally, the first installation area 2211, the second installation area 2212 and the third installation area 2213 are coated with an electrolyte-repellent coating 30, and the contact angle θ1 between the electrolyte-repellent coating 30 and the electrolyte is in the range of 140°≤θ1≤160°. At the same time, the first flow guide area 2221 is coated with an electrolyte-philic coating 40, and the contact angle θ1 between the electrolyte-philic coating 40 and the electrolyte is 21 The optional range is 20°≤θ 21 ≤40°; the contact angle of the second flow guiding area 2222 is θ 22 The optional range is 80°≤θ 22 ≤100°.

[0158] On the one hand, it can ensure that the flow characteristics of the electrolyte in the first guide area 2221 and the second guide area 2222 have certain differences, so that the electrolyte overflowing from the injection hole can be mainly gathered in the first guide area 2221, which can reduce the impact on the first electrode terminal 241 and the pressure relief mechanism 25. Since there is no injection hole 27 on the second guide area 2222, the electrolyte that may drip on the second guide area 2222 is less than the electrolyte in the first guide area 2221, so the second guide area 2222 has lower requirements for electrolyte adsorption and diversion. Therefore, on the basis of ensuring that the contact angle of the second guide area 2222 is smaller than the contact angle of the first guide area 2221, the contact angle of the second guide area 2222 can be set larger, effectively avoiding the problem of too high requirements on the polishing process of the surface of the second guide area 2222 or too stringent requirements on the quality of the coating due to too large or too small contact angle, thereby reducing production costs.

[0159] Optionally, along the width direction of the end cap 22 (ie Figure 3 The first guide area 2221 and the second guide area 2222 extend to the ends of the end cap 22. The second wall is the first side wall 231 of the shell 21 connected to one end of the end cap 22 in the width direction. The area of ​​the first side wall 231 of the shell 21 at the ends of the end cap 22 in the width direction is greater than the area of ​​the second side wall 232 of the shell 21 at the ends of the end cap 22 in the length direction. The first part 291 of the electrophilic electrolyte coating 40 covers the first guide area 2221, and the second part 292 of the electrophilic electrolyte coating 40 covers at least part of the first side wall 231 and is connected to the first part 291, so that the overflow carried on the end cap 22 can be smoothly drained to the first side wall 231 of the shell 21 with a larger area, forming an area conducive to the flow of the electrolyte. Once the overflow occurs, the first part 291 of the electrophilic electrolyte coating 40 located on the first guide area 2221 can guide the electrolyte to flow to the surface of the second part 292 located on the first side wall 231, which is easy to clean later.

[0160] Optionally, along the height direction of the battery cell 20 (ie Figure 3The length of the second portion 292 can be designed according to actual needs, and the second portion 292 can extend to the middle or bottom of the first side wall. In addition, the shape and size of the second portion 292 can be set to gradually increase the size of the end away from the end cover 22. For example, in the height direction of the battery cell 20, the second portion 292 is a trapezoidal shape that is narrow at the top and wide at the bottom, and the second end of the second portion 292 is located in the middle of the height direction of the side wall.

[0161] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: A housing, the housing having a first wall, an outer surface of the first wall comprising a first region and a second region, a contact angle between the first region and the electrolyte being greater than a contact angle between the second region and the electrolyte; An electrode terminal and a pressure relief mechanism, at least one of the electrode terminal and the pressure relief mechanism is disposed in the first region.

2. The battery cell according to claim 1, characterized in that: The electrode terminal and the pressure relief mechanism are both arranged in the first area.

3. The battery cell according to claim 1, characterized in that: The first region is coated with an electrophobic coating.

4. The battery cell according to claim 1, characterized in that: The second region is coated with an electrophilic electrolyte coating.

5. The battery cell according to any one of claims 1 to 4, characterized in that: The battery cell further includes a liquid injection hole, which is disposed in the second region and is used to inject electrolyte into the housing.

6. The battery cell according to claim 1, characterized in that: There are multiple first regions, and the multiple first regions are arranged at intervals along the first direction. The second region is arranged between any two adjacent first regions.

7. The battery cell according to claim 6, characterized in that: The plurality of first areas include a first installation area and a second installation area spaced apart along a first direction, and the second area includes a first guide area disposed between the first installation area and the second installation area; The electrode terminal includes a first electrode terminal, the first electrode terminal is arranged in the first installation area, and the pressure relief mechanism is arranged in the second installation area.

8. The battery cell according to claim 7, characterized in that: The first area further includes a third installation area, and along the first direction, the third installation area and the second installation area are arranged at intervals; the second area further includes a second guide area arranged between the second installation area and the third installation area; The electrode terminal further includes a second electrode terminal, and the second electrode terminal is disposed in the third mounting area.

9. The battery cell according to claim 8, characterized in that: The first installation area, the second installation area and the third installation area are all coated with an electrophobic electrolyte coating.

10. The battery cell according to any one of claims 7 to 9, characterized in that: The battery cell further includes a liquid injection hole, and the liquid injection hole is arranged in the first guide area.

11. The battery cell according to claim 10, characterized in that: The first flow-conducting area is coated with an electrophilic electrolyte coating.

12. The battery cell according to claim 11, characterized in that: The housing further comprises a second wall, which is disposed adjacent to the first wall; the electrophilic electrolyte coating comprises a first portion and a second portion which are disposed continuously, the first portion being coated on the first guide area, and the second portion being coated on the outer surface of the second wall.

13. The battery cell according to claim 12, characterized in that: In the thickness direction of the first wall, the second portion has a first end close to the first portion and a second end far away from the first portion, and the width of the second portion gradually increases from the first end to the second end.

14. The battery cell according to claim 1, characterized in that: The housing includes a shell and an end cover, the shell has an opening, the end cover is connected to the shell to seal the opening, and the end cover is the first wall.

15. A battery, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 14.

16. An electrical device, characterized in that: The invention comprises the battery cell according to any one of claims 1 to 14 and / or the battery according to claim 15, wherein the battery cell and / or the battery are used to provide electrical energy.

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