CN116636071A

CN116636071A - Pressure balancing mechanism, battery, power utilization device, method and device for preparing battery

Info

Publication number: CN116636071A
Application number: CN202180084450.1A
Authority: CN
Inventors: 陈彬彬
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2021-09-24
Filing date: 2021-09-24
Publication date: 2023-08-22
Also published as: WO2023044764A1

Abstract

The embodiment of the application provides a pressure balancing mechanism, a battery, an electric device, a method and a device for preparing the battery. The pressure balance mechanism is used for a battery to balance the pressure inside and outside the battery, and comprises: a body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening; the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through; the breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable film is used for enabling gas to pass through and preventing condensate from passing through. By the technical scheme provided by the embodiment of the application, the safety of the battery can be enhanced.

Description

Pressure balancing mechanism, battery, power utilization device, method and device for preparing battery

Technical Field

The application relates to the technical field of batteries, in particular to a pressure balancing mechanism, a battery, an electric device, a method and a device for preparing the battery.

Background

With the increasing increase of environmental pollution, the new energy industry is receiving more and more attention. In the new energy industry, battery technology is an important factor in its development. In the development of battery technology, safety issues are a non-negligible issue. If the safety problem of the battery is not guaranteed, the battery cannot be used.

Under normal conditions, the pressure balance mechanism in the battery can meet ventilation requirements and is impermeable, so that the problems of short circuit and the like of an electric connector inside the battery can be prevented while the internal and external pressure balance of the battery is maintained. However, the existing pressure balance mechanism can only realize ventilation and water resistance, but can not prevent water vapor in the air from passing through, and when the water vapor enters the battery through the pressure balance mechanism, condensate is generated in the battery due to temperature change, so that potential safety hazards are caused, and the safety of the battery is affected. Therefore, how to enhance the safety of the battery is a technical problem to be solved in the battery technology.

Disclosure of Invention

The application provides a pressure balancing mechanism, a battery, an electric device, a method and a device for preparing the battery, which can enhance the safety of the battery.

In a first aspect, there is provided a pressure balancing mechanism for a battery to balance pressure inside and outside the battery, the pressure balancing mechanism comprising: a body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening; the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through; the breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable film is used for enabling gas to pass through and preventing condensate from passing through.

According to the embodiment of the application, the channel is formed in the main body of the pressure balancing mechanism, so that gas can be condensed in the channel, meanwhile, the condensing sheet at the end part of the channel can accelerate the condensation of the gas, so that the water vapor entering the battery after passing through the breathable film is reduced as much as possible, the internal and external pressure balance of the battery is maintained, the influence on the battery after the water vapor is condensed is reduced, and the safety of the battery is enhanced.

In one possible implementation, the pressure balancing mechanism further includes: a piston member configured to be inserted into the passage via the first opening and fixedly connected with the main body.

Through setting up the piston component, can further restrict and lengthen the route of the gas in the passageway for can reach the condensation piece along the route that presets after the gas gets into the passageway, realize the condensation to vapor in the gas, further improve the condensation effect, reduce the influence of condensate to the battery inside, strengthen the security of battery.

In one possible implementation, a first gap is provided between the piston member and the channel to form a flow path for the gas.

Through forming first clearance between piston component and passageway for gas can get into the passageway inside through this first clearance and condense, reduce the influence of gaseous vapor to the battery, strengthen the security of battery.

In one possible implementation, the inner surface of the channel, and/or the outer surface of the piston member is provided with grooves to form the flow path of the gas.

The grooves between the piston component and the channels can form a gas flow path, so that the gas can enter the channels through the grooves to be condensed, the influence of water vapor in the gas on the battery is reduced, and the safety of the battery is enhanced.

In one possible implementation, the grooves are helical.

In the embodiment of the application, the spiral grooves can further prolong the flow path of the gas in the channel, so that the vapor in the gas can be further condensed, the influence of the vapor in the gas on the battery is reduced, and the safety of the battery is enhanced.

In one possible implementation, the piston member includes a fixed portion and an insertion portion connected, the insertion portion being configured to be inserted into the channel, the fixed portion being configured to be fixedly connected to the main body, wherein a second gap is provided between the fixed portion and the first opening, such that the gas enters the channel through the second gap.

The piston component can be fixed through the connecting fixing part and the inserting part, and the piston component with the structure has simple structure and easy assembly.

In one possible implementation, the edge of the fixing portion is provided with a protrusion, the edge of the main body is provided with a notch, and the protrusion and the notch cooperate to fix the piston member to the main body.

In the embodiment of the application, the fixing mode of the piston member can adopt a mode that the bulges and the gaps are matched with each other, no additional part is needed for fixing, and the piston member is simple in structure and convenient to operate.

In one possible implementation, the pressure balancing mechanism further includes: a cover for covering the first opening and being connected to the main body, wherein a third gap is provided between the cover and the first opening such that the gas enters the channel through the third gap.

According to the pressure balancing mechanism, the channel and the external environment can be separated through the covering piece, so that the temperature inside the channel is not easy to be influenced by the temperature of the external environment, the gas entering the channel can be sufficiently and effectively condensed, the influence of water vapor in the gas on a battery is reduced, and the safety of the battery is enhanced.

In a possible implementation manner, a liquid drain communicated with the first opening is arranged in the channel, and the liquid drain is used for draining the condensate out of the channel.

In the embodiment of the application, the condensate is generated after the gas is condensed in the channel, and the generated condensate can be timely discharged to the outside of the channel by arranging the liquid outlet communicated with the first opening, so that the adverse effect of the condensate accumulation on the condensation effect of the channel is avoided.

In one possible implementation, the pressure balancing mechanism further includes: the protection piece is arranged on one side, far away from the second opening, of the breathable film and is fixedly connected with the main body, the protection piece is used for protecting the breathable film, and the protection piece is provided with a through hole used for enabling gas to pass through.

The breathable film in the embodiment of the application is arranged at the outermost side of the whole pressure balance mechanism, and is easy to be damaged by the outside if the breathable film is not protected correspondingly. Through setting up above-mentioned protection piece, can avoid the ventilated membrane to receive external damage, simultaneously, be provided with the through-hole on the protection piece for the protection piece can allow gas to pass through, and enter into the inside of battery, thereby maintain the balance of the inside and outside pressure of battery.

In a second aspect, there is provided a battery comprising: the battery pack comprises a plurality of battery cells and a box body, wherein the battery cells are accommodated in the box body; and the pressure balance mechanism according to the first aspect, wherein the pressure balance mechanism is provided on the case.

In a third aspect, there is provided an electrical device comprising: the battery according to the second aspect, the battery being for supplying electric power.

In one possible implementation, the electricity-consuming device is a vehicle, a ship, or a spacecraft.

In a fourth aspect, there is provided a method of preparing a battery, comprising: providing a plurality of battery cells and a box body, wherein the battery cells are accommodated in the box body; providing a pressure balancing mechanism for the battery is used for balancing the pressure inside and outside the battery, the pressure balancing mechanism is arranged on the box body, and the pressure balancing mechanism comprises: a body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening; the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through; the breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable film is used for enabling gas to pass through and preventing condensate from passing through.

In a fifth aspect, there is provided an apparatus for preparing a battery, comprising: the first providing module is used for providing a plurality of battery monomers and a box body, and the battery monomers are accommodated in the box body; the second provides the module for provide pressure balance mechanism, be used for the battery is in order to balance the inside and outside pressure of battery, pressure balance mechanism set up in on the box, pressure balance mechanism includes: a body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening; the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through; the breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable film is used for enabling gas to pass through and preventing condensate from passing through.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of a vehicle according to an embodiment of the present application;

fig. 2 is a schematic view showing the structure of a battery according to an embodiment of the present application;

fig. 3 is a schematic structural view of a battery cell stack according to an embodiment of the present application;

fig. 4 is an exploded view of a battery cell according to an embodiment of the present application;

fig. 5 is an exploded view of a battery cell according to another embodiment of the present application;

FIG. 6a is an exploded view of a pressure balancing mechanism according to one embodiment of the present application;

FIGS. 6b to 6c are schematic structural views of the pressure balancing mechanism at different angles corresponding to FIG. 6 a;

FIG. 7 is an exploded view of a pressure balancing mechanism according to another embodiment of the present application;

FIG. 8a is a schematic view of a body according to an embodiment of the present application;

FIG. 8b is a schematic cross-sectional view corresponding to FIG. 8 a;

FIG. 9 is a schematic cross-sectional view of a pressure balancing mechanism corresponding to that of FIGS. 7-8 b;

FIG. 10 is a schematic view of a body according to another embodiment of the present application;

FIG. 11 is a schematic view of a body according to another embodiment of the present application;

FIG. 12 is an exploded view of a pressure balancing mechanism according to another embodiment of the present application;

FIG. 13 is a schematic view of a pressure balancing mechanism according to another embodiment of the present application;

fig. 14a is a schematic view of a battery case according to an embodiment of the present application;

FIG. 14b is a partial detail view corresponding to position C in FIG. 14 a;

fig. 15 is a schematic flow chart of a method of preparing a battery according to an embodiment of the present application;

fig. 16 is a schematic block diagram of an apparatus for preparing a battery according to an embodiment of the present application.

In the drawings, the drawings are not drawn to scale.

Detailed Description

Embodiments of the present application are described in further detail below with reference to the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the application and are not intended to limit the scope of the application, i.e., the application is not limited to the embodiments described.

In the description of the present application, it is to be noted that, unless otherwise indicated, the meaning of "plurality" is two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like are merely used for convenience in describing the present application and to simplify the description, and do not denote or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The "vertical" is not strictly vertical but is within the allowable error range. "parallel" is not strictly parallel but is within the tolerance of the error.

The directional terms appearing in the following description are those directions shown in the drawings and do not limit the specific structure of the application. In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present application can be understood as appropriate by those of ordinary skill in the art.

In the present application, the battery cell may include a primary battery and a secondary battery, and may be, for example, a lithium ion battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, or a magnesium ion battery, which is not limited by the embodiment of the present application. The battery cell may be in a cylindrical, flat, rectangular or other shape, etc., and the embodiment of the present application is not limited thereto. The battery cells are generally classified into three types according to the packaging method: the cylindrical battery cell, the square battery cell and the soft package battery cell are not limited in this embodiment.

Reference to a battery in accordance with an embodiment of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery cell stack or a battery pack, or the like. The battery pack generally includes a case for enclosing one or more battery cells. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive plate, a negative plate and a separation membrane. The battery cell mainly relies on metal ions to move between the positive and negative electrode plates to operate. The positive plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, the current collector without the positive electrode active material layer protrudes out of the current collector coated with the positive electrode active material layer, and the current collector without the positive electrode active material layer is used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The negative electrode sheet comprises a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is coated on the surface of the negative electrode current collector, the current collector without the negative electrode active material layer protrudes out of the current collector with the coated negative electrode active material layer, and the current collector without the negative electrode active material layer is used as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the high current is passed without fusing, the number of positive electrode lugs is multiple and stacked together, and the number of negative electrode lugs is multiple and stacked together. The material of the isolation film can be polypropylene (PP) or Polyethylene (PE). In addition, the electrode assembly may be a roll-to-roll structure or a lamination structure, and embodiments of the present application are not limited thereto. The development of battery technology is taking into consideration various design factors such as energy density, cycle life, discharge capacity, charge-discharge rate and other performance parameters, and the safety of the battery.

For batteries, the main safety hazard comes from the charging and discharging process, and in order to improve the safety performance of the battery, the battery is generally provided with a pressure balancing mechanism. The pressure balancing mechanism can maintain the balance of the internal and external pressures of the battery.

In the current design, the pressure balancing mechanism can comprise a ventilated membrane, and when the pressure difference exists in the internal environment and the external environment of the battery, the ventilated membrane can allow gas to pass through, so that the balance of the internal environment and the external environment of the battery is ensured. Under normal conditions, the breathable film in the pressure balancing mechanism has breathability, allows gas to pass through, and meanwhile, the breathable film can prevent liquid water from passing through, so that the liquid water can be prevented from entering the inside of the battery while the pressure balance inside and outside the battery is maintained, and the problems of short circuit and the like of an electric connector inside the battery are avoided. However, the permeable membrane in the pressure balancing mechanism cannot prevent water vapor in the gas from entering the battery, and when the ambient temperature of the battery changes, the water vapor entering the battery can be condensed into condensate or liquid water, which causes potential safety hazards to the inside of the battery, such as an electric connector, and affects the safety of the battery.

In order to solve this problem, in the current design, an air dryer is generally provided in the pressure balancing mechanism, and the desiccant in the air dryer absorbs water vapor entering the inside of the battery. However, the desiccant has a limited capacity to absorb water vapor, and requires periodic replacement, and the pressure balancing mechanism using the desiccant is generally complex in structure and high in cost.

In view of this, the embodiment of the application provides a technical solution, by forming a channel in the main body of the pressure balancing mechanism, so that the gas can be condensed in the channel, and at the same time, the condensation sheet at the end of the channel can accelerate the condensation of the gas, so as to reduce the water vapor entering the battery after passing through the gas permeable membrane as much as possible, thereby reducing the influence on the battery inside, such as an electric connector, after the water vapor is condensed while maintaining the internal and external pressure balance of the battery, and enhancing the safety of the battery.

The technical solutions described in the embodiments of the present application are applicable to various devices using batteries, for example, mobile phones, portable devices, notebook computers, battery cars, electric toys, electric tools, electric vehicles, ships, spacecraft, and the like, and for example, spacecraft include airplanes, rockets, space shuttles, spacecraft, and the like.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to the above-described devices, but may be applied to all devices using batteries, but for simplicity of description, the following embodiments are described by taking an electric vehicle as an example.

For example, as shown in fig. 1, a schematic structural diagram of a vehicle 1 according to an embodiment of the present application is shown, where the vehicle 1 may be a fuel-oil vehicle, a gas-fired 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. The vehicle 1 may be provided with a motor 40, a controller 30 and a battery 10, the controller 30 being arranged to control the battery 10 to supply power to the motor 40. For example, the battery 10 may be provided at the bottom or the head or the tail of the vehicle 1. The battery 10 may be used for power supply of the vehicle 1, e.g. the battery 10 may be used as an operating power source for the vehicle 1, for electrical circuitry of the vehicle 1, e.g. for start-up, navigation and operational power requirements of the vehicle 1. In another embodiment of the present application, the battery 10 may be used not only as an operating power source for the vehicle 1 but also as a driving power source for the vehicle 1, instead of or in part instead of fuel oil or natural gas, to supply driving power to the vehicle 1.

In order to meet different power requirements, the battery of the application can comprise a plurality of battery cells, wherein the plurality of battery cells can be connected in series or in parallel or in series-parallel, and the series-parallel refers to the mixture of series connection and parallel connection. The battery may also be referred to as a battery pack. Optionally, the plurality of battery cells may be connected in series or parallel or in series-parallel to form a battery module, and then the plurality of battery modules are connected in series or parallel or in series-parallel to form a battery. That is, a plurality of battery cells may be directly assembled into a battery, or may be assembled into a battery module first, and the battery module may be assembled into a battery.

For example, as shown in fig. 2, a battery 10 according to an embodiment of the present application may include a plurality of battery cells 20. The battery 10 may further include a case having a hollow structure therein, and the plurality of battery cells 20 are accommodated in the case. As shown in fig. 2, the case may include two parts, referred to herein as a case first part 111 and a case second part 112, respectively, the case first part 111 and the case second part 112 being snapped together. The shape of the case first part 111 and the case second part 112 may be determined according to the combined shape of the battery cells 20, and the case first part 111 and the case second part 112 may each have one opening. For example, the first case portion 111 and the second case portion 112 may each be a hollow rectangular parallelepiped and each have only one face as an open face, the opening of the first case portion 111 and the opening of the second case portion 112 are disposed opposite to each other, and the first case portion 111 and the second case portion 112 are fastened to each other to form a case having a closed chamber. The plurality of battery cells 20 are connected in parallel or in series-parallel combination and then placed in a box body formed by buckling the first box body part 111 and the second box body part 112.

Alternatively, the battery 10 may further include other structures, which are not described in detail herein. For example, the battery 10 may further include a bus member for making electrical connection between the plurality of battery cells 20, such as parallel or series-parallel connection. Specifically, the bus member may realize electrical connection between the battery cells 20 by connecting electrode terminals of the battery cells 20. Further, the bus member may be fixed to the electrode terminals of the battery cells 20 by welding. The electrical energy of the plurality of battery cells 20 may be further drawn through the housing by a conductive mechanism.

The number of battery cells may be set to any number according to different power requirements. The plurality of battery cells can be connected in series, parallel or series-parallel to realize larger capacity or power. Since the number of battery cells included in each battery 10 may be large, the battery cells may be arranged in groups for easy installation, with each group of battery cells constituting the battery cell stack 200. The number of battery cells included in the battery cell stack 200 is not limited, and may be set according to requirements. For example, fig. 3 is an example of a battery cell stack. The battery may include a plurality of battery cell stacks that may be connected in series, parallel, or series-parallel.

As shown in fig. 4, a schematic structure of a battery cell 20 according to an embodiment of the present application, the battery cell 20 includes one or more electrode assemblies 22, a case 211, and a cap plate 212. The housing 211 and the cover 212 form the case 21. The walls of the housing 211 and the cover 212 are referred to as the walls of the battery cells 20. The case 211 is determined according to the shape of the combined one or more electrode assemblies 22, for example, the case 211 may be a hollow rectangular parallelepiped or square or cylindrical body, and one face of the case 211 has an opening so that one or more electrode assemblies 22 may be placed in the case 211. For example, when the housing 211 is a hollow rectangular parallelepiped or square, one of the planes of the housing 211 is an opening surface, i.e., the plane has no wall body so that the inside and outside of the housing 211 communicate. When the housing 211 may be a hollow cylinder, the end surface of the housing 211 is an open surface, i.e., the end surface has no wall body so that the inside and outside of the housing 211 communicate. The cap plate 212 covers the opening and is connected with the case 211 to form a closed cavity in which the electrode assembly 22 is placed. The housing 211 is filled with an electrolyte, such as an electrolyte solution.

The battery cell 20 may further include two electrode terminals 214, and the two electrode terminals 214 may be disposed on the cap plate 212. The cap plate 212 is generally in the shape of a flat plate, and two electrode terminals 214 are fixed to the flat plate surface of the cap plate 212, the two electrode terminals 214 being a positive electrode terminal 214a and a negative electrode terminal 214b, respectively. Each electrode terminal 214 is provided with a connection member 23, which is positioned between the cap plate 212 and the electrode assembly 22, for electrically connecting the electrode assembly 22 and the electrode terminal 214.

As shown in fig. 4, each electrode assembly 22 has a first tab 221a and a second tab 222a. The polarities of the first tab 221a and the second tab 222a are opposite. For example, when the first tab 221a is a positive tab, the second tab 222a is a negative tab. The first tab 221a of one or more electrode assemblies 22 is connected to one electrode terminal 214 through one connection member 23, and the second tab 222a of one or more electrode assemblies 22 is connected to the other electrode terminal 214 through the other connection member 23. For example, the positive electrode terminal 214a is connected to the positive electrode tab through one connection member 23, and the negative electrode terminal 214b is connected to the negative electrode tab through the other connection member 23.

In the battery cell 20, the electrode assemblies 22 may be provided in a single unit, or in a plurality, according to actual use requirements, as shown in fig. 4, and 4 electrode assemblies 22 are provided in the battery cell 20.

As shown in fig. 5, a schematic structural diagram of a battery cell 20 including a pressure release mechanism 213 according to another embodiment of the present application is shown.

The case 211, the cover plate 212, the electrode assembly 22 and the connection member 23 in fig. 5 are identical to the case 211, the cover plate 212, the electrode assembly 22 and the connection member 23 in fig. 4, and are not described again here for brevity.

In fig. 5, the pressure release mechanism 213 is disposed on the bottom wall of the battery cell 20, that is, the wall 21a in fig. 5, wherein the pressure release mechanism 213 may be a part of the wall 21a or may be a separate structure from the wall 21a, and is fixed to the wall 21a by, for example, welding. When the pressure relief mechanism 213 is a part of the wall 21a, for example, the pressure relief mechanism 213 may be formed by providing a score on the wall 21a, and the thickness of the wall 21a corresponding to the score is smaller than the thickness of the pressure relief mechanism 213 in other areas than the score. The score is the weakest point of the pressure relief mechanism 213. When the pressure in the housing 211 rises and reaches the threshold due to too much gas generated by the battery cell 20 or the temperature in the battery cell 20 rises and reaches the threshold due to heat generated by the reaction in the battery cell 20, the pressure release mechanism 213 may rupture at the notch to cause the inside and outside of the housing 211 to communicate, and the gas pressure and temperature are released outwards through the rupture of the pressure release mechanism 213, so as to avoid explosion of the battery cell 20.

In fig. 5, the pressure release mechanism 213 is illustrated as being located on the bottom wall of the battery cell 20, but it should be understood that the pressure release mechanism 213 in the embodiment of the present application may be located on the side wall of the housing 211, or may be located on the cover 212, or may be located at the intersection of two walls of the housing 211, which is not limited in this embodiment of the present application.

The pressure relief mechanism 213 may be any of a variety of possible pressure relief structures, and embodiments of the present application are not limited in this regard. For example, the pressure release mechanism 213 may be a temperature-sensitive pressure release mechanism configured to be able to melt when the internal temperature of the battery cell 20 provided with the pressure release mechanism 213 reaches a threshold value; and/or the pressure relief mechanism 213 may be a pressure sensitive pressure relief mechanism configured to rupture when the internal air pressure of the battery cell 20 provided with the pressure relief mechanism 213 reaches a threshold value.

Further, in order to maintain the pressure balance inside and outside the battery, a pressure balance mechanism may be provided on the battery, so that the pressure balance inside and outside the battery may be maintained. However, in the current design of the pressure balancing mechanism, the breathable film in the pressure balancing mechanism has the functions of breathability and water resistance, but cannot block the influence of water vapor in the gas on the battery. Based on this, fig. 6a shows an exploded view of a pressure balancing mechanism 12 in an embodiment of the present application, and fig. 6b to 6c are schematic views of the assembled pressure balancing mechanism corresponding to fig. 6a under different angles, and by using the pressure balancing mechanism 12 in an embodiment of the present application, the influence of water vapor in the gas on the electrical connection inside the battery after condensation can be reduced, and the safety of the battery is enhanced.

As shown in fig. 6a to 6c, the pressure balancing mechanism 12 may include a body 121, a condensing sheet 122, and a gas permeable membrane 123. The pressure balancing mechanism 12 may be used in a battery to balance the pressure inside and outside the battery.

Wherein the inside of the body 121 is formed with a channel 1211, both ends of the channel 1211 have a first opening 1211a and a second opening 1211b, the first opening 1211a for guiding gas to the channel 1211; the condensation piece 122 is used for covering the second opening 1211b and is fixedly connected with the main body 121, the condensation piece 122 and the channel 1211 are used for condensing vapor in the gas into condensate, and the condensation piece 122 is provided with ventilation holes for allowing the gas to pass through; the gas permeable membrane 12 is disposed at a side of the condensation sheet 122 remote from the second opening 1211b and fixedly connected to the main body 121, and the gas permeable membrane 123 is used to pass gas and prevent condensate from passing.

By forming the channel 1211 in the main body 121 of the pressure balancing mechanism 12, the gas can be condensed in the channel 1211, meanwhile, the condensation plate 122 at the end of the channel 1211 can accelerate the condensation of the water vapor in the gas, so that the water vapor entering the battery after passing through the gas permeable membrane 123 is reduced as much as possible, and the safety of the battery is enhanced by reducing the influence on the battery inside, such as an electric connector, after the water vapor is condensed while maintaining the pressure balance inside and outside the battery.

The pressure balancing mechanism 12 in the embodiment of the present application may be disposed on a casing of a battery, where one end of the main body 121 provided with the condensation sheet 122 may be located inside the battery, so that gas may first enter the channel 1211 through the first opening 1211a before entering the battery, the gas may undergo a certain temperature change in the channel 1211, so that part of the vapor in the gas may be condensed on the inner surface of the channel 1211 to form condensate, or liquid water, further, the gas may contact the condensation sheet 122 after passing through the channel 1211, under the effect of the condensation sheet 122, the condensation process of the vapor in the gas may be accelerated, so that the vapor in the gas may be condensed into condensate, meanwhile, due to the air hole disposed on the condensation sheet 122, part of the vapor or a small amount of the vapor in the gas may reach the air-permeable membrane 123 through the air hole on the condensation sheet 122, and finally may enter the battery through the air-permeable membrane 123. In this process, because the gas has passed through the channel 1211 and the condensation plate 122 before reaching the gas permeable membrane 123, the pressure balancing mechanism 12 in the embodiment of the application can greatly reduce the water vapor contained in the gas, reduce the influence of the water vapor entering the battery on the battery, and enhance the safety of the battery.

The pressure balance mechanism 12 in the embodiment of the present application may also be called a balance valve, an explosion-proof valve, etc., and its main function is to maintain the balance of the pressures inside and outside the battery, and the name of the embodiment of the present application is not limited.

Alternatively, the ventilation holes formed in the condensation plate 122 in the embodiment of the present application may take various forms, for example, the condensation plate 122 may be integrally formed into a fine mesh structure, so that the area through which the gas passes may be increased, and the gas circulation may be quickened, so as to ensure that the pressure inside and outside the battery is balanced greatly, or one or more through holes may be formed in the condensation plate 122 to allow the gas to pass through the condensation plate 122, and the specific arrangement may be determined according to the battery requirement, which is not limited in the embodiment of the present application.

As one implementation, the condensation plate 122 in an embodiment of the present application may be a material having a high thermal conductivity, such as a metal material. In general, the higher the thermal conductivity of the material, the better the thermal conductivity, and the condensation plate 122 in the embodiment of the application adopts the material with high thermal conductivity, which is more beneficial to the condensation plate 122 to take away the high temperature of the gas and to condense the vapor in the gas.

Alternatively, the condensing sheet 122 in an embodiment of the present application may be a stainless steel material, such as 304 stainless steel, or the like.

In the above embodiment, the gas is condensed only through the passage 1211 and the condensation plate 122 formed in the body 121, but the condensing effect is limited although the gas can be condensed in the passage 1211, and in order to further improve the condensing effect of the pressure balancing mechanism 12 in the embodiment of the present application, it may be achieved by further extending the flow path of the gas.

As one implementation, the pressure balancing mechanism 12 may further include: the piston member 124 is configured to be inserted into the passage 1211 through the first opening 1211a and fixedly connected with the body 121.

Fig. 7 shows an exploded view of one of the pressure balancing mechanisms 12 having a piston member 124 in an embodiment of the present application. As shown in fig. 7, the piston member 124 may be inserted into the channel 1211, and a surface of a portion of the piston member 124 located in the channel 1211 may form a path allowing passage of gas with an inner surface of the channel 1211. Specifically, a first gap is provided between the piston member 124 and the passage 1211 to form a flow path of the gas.

By providing the piston member 124, the path of the gas entering the channel 1211 can be further limited and prolonged, so that the gas can reach the condensation plate 122 along a preset path after entering the channel 1211, thereby realizing sufficient condensation of water vapor in the gas, further improving the condensation effect, reducing the influence of condensate on the inside of the battery, and enhancing the safety of the battery.

In order to form a flow path allowing gas between the piston member 124 and the passage 1211, as one implementation, a portion of the piston member 124 located within the passage 1211 may be provided having a radial dimension smaller than that of the passage 1211, such that the above-described first gap may be formed between the piston member 124 and the passage 1211 such that gas may reach the condensation plate 122 through the first gap.

Alternatively, as another implementation, the inner surface of the channel 1211, and/or the outer surface of the piston member 124 is provided with grooves 125 to form a flow path for the gas. Optionally, the grooves 125 are helical. The helical groove 125 in the embodiment of the present application may also be referred to as a helical groove 125.

Specifically, as an example, fig. 8a shows a structural illustration of a body 121 provided with a spiral groove 125. Fig. 8b is a cross-sectional view corresponding to fig. 8 a. As shown in fig. 8a and 8b, the spiral groove 125 is disposed on the inner surface of the channel 1211, and one end thereof extends to the end of the first opening 1211a to allow the gas to enter the spiral groove 125 through the first opening 1211a, and the other end extends to the second opening 1211b to allow the gas to pass through the spiral groove 125 and then reach the condensing plate 122 for condensation.

By providing the spiral groove 125 on the inner surface of the channel 1211 and/or the outer surface of the piston member 124, a flow path for gas may be formed between the channel 1211 and the piston member 124. Alternatively, when the inner surface of the channel 1211, and/or the outer surface of the piston member 124 is provided with the helical groove 125, the radial dimension of the piston member 124 may be less than or equal to the radial dimension of the channel 1211.

Alternatively, the groove 125 may be configured in other shapes, such as a linear groove passing through the channel 1211, which is not limited in the embodiment of the present application.

Further, in order to fix the piston member 124 to the body 121, as shown in fig. 7, the piston member 124 may include a fixing portion 1241 and an insertion portion 1242. Specifically, the piston member 124 includes a fixing portion 1241 and an insertion portion 1242 connected, the insertion portion 1242 being for insertion into the passage 1211, the fixing portion 1241 being for fixed connection with the main body 121, wherein a second gap is provided between the fixing portion 1241 and the first opening 1211a such that gas enters the passage 1211 through the second gap.

To fix the fixing portion 1241 to the body 121, as one implementation, an edge of the fixing portion 1241 is provided with a protrusion 1243, and an edge of the body 121 is provided with a notch 1212, and the protrusion 1243 and the notch 1212 cooperate to fix the piston member 124 to the body 121.

Alternatively, the embodiment of the present application may provide a groove accommodating the fixing portion 1241 at the first opening 1211a of the body 121, such as the groove region 1213 shown in fig. 7, and the groove region 1213 may be circular or may have other shapes, to which the embodiment of the present application is not limited. Accordingly, the fixing portion 1241 may have a cylindrical structure to be engaged with the groove region 1213 to fix the fixing portion 1241 to the body 121.

Further, in order that the gas may enter the channel 1211 through the fixing portion 1241, a gap allowing the gas to pass through may be provided between the fixing portion 1241 and the groove region 1213, alternatively, the gap may be provided in various manners, for example, the radial dimension of the fixing portion 1241 may be smaller than the radial dimension of the groove region 1213, so that the aforementioned second gap may be formed between the fixing portion 1241 and the groove region 1213 when the fixing portion 1241 is fixed to the body 121, and the second gap may allow the gas to pass through.

Or alternatively, a notch may be provided directly on the fixing portion 1241, so that gas may directly enter the channel 1211 from the notch, which is not limited by the embodiment of the present application.

It should be understood that the aforementioned fastening means of the pressure balance mechanism 12 by the protrusions 1243 and the notches 1212 may be combined with the fastening means of the recess area 1213 provided on the main body 121, or may be implemented separately, which is not limited in the embodiment of the present application.

Or alternatively, the piston member 124 in the embodiment of the present application may be fixed to the body 121 by other means, such as bonding, riveting, welding, etc., to which the embodiment of the present application is not limited.

Fig. 9 shows a schematic cross-sectional illustration of a pressure equalization mechanism 12 with a piston member 124 corresponding to fig. 7 to 8 b. As shown in fig. 9, the piston member 124 may have a fixing portion 1241 and an insertion portion 1242, wherein the piston member 124 may cooperate with the notch 1212 through the projection 1243 to fix the piston member 124. Further, a groove region 1213 as described in the foregoing embodiment may be provided in the body 121 so that the fixing portion 1241 may be fitted with the groove region 1213 to achieve fixing. Wherein the radial dimension of the fixation portion 1241 may be smaller than the radial dimension of the groove region 1213, such that a gap may be formed between the fixation portion 1241 and the groove region 1213 through which gas may enter the channel 1211. The gas may then pass through the spiral grooves 125 in the channels 1211 to the condensing fins 122 for condensation. Wherein the path through which the gas passes may refer to the direction of the arrow shown in fig. 9.

In the embodiment of the present application, the water vapor in the gas may be condensed into condensate before passing through the gas permeable membrane 123, so as to reduce the influence of the water vapor entering the battery on the battery, and accordingly, after the water vapor in the gas is condensed in the channel 1211, the condensed condensate needs to be discharged out of the channel 1211, so as to avoid affecting the condensation effect of the channel 1211. Specifically, a drain 1214 communicating with the first opening 1211a is provided in the passage 1211, and the drain 1214 is for draining condensate out of the passage 1211.

The liquid drain port may be disposed in various manners, for example, the liquid drain port 1214 shown in fig. 7 to 9, one or more liquid drain ports 1214 may be disposed in communication with the first opening 1211a in the embodiment of the present application, and the liquid drain port 1214 may extend to communicate with the groove 125 in the previous embodiment, so that the liquid water stored in the groove 125 may be drained out of the channel 1211 through the liquid drain port 1214.

Alternatively, the length of the drain 1214 may be the same as the length of the channel 1211, or may extend only from the first opening 1211a to a distance within the channel 1211, and in addition, the location of the drain 1214 may be set according to the actual requirement, which is not limited in the embodiment of the present application.

The breathable film 123 in the embodiment of the present application is disposed at the outermost side of the entire pressure balancing mechanism 12, and is easily damaged by the outside without corresponding protection.

As one implementation, the pressure balancing mechanism 12 further includes: and a protector 127 disposed at a side of the gas permeable membrane 123 remote from the second opening 1211b and fixedly connected with the body 121, the protector 127 being for protecting the gas permeable membrane 123, the protector 127 having a through hole for passing a gas therethrough.

The protector 127 in the pressure balancing mechanism 12 as shown in fig. 7 can prevent the air-permeable membrane 123 from being damaged by the outside by providing the protector 127 described above, and at the same time, the protector 127 is provided with the through-holes 1271 so that the protector 127 can allow the gas passing through the air-permeable membrane 123 to pass through and enter the inside of the battery, thereby maintaining the balance of the internal and external pressures of the battery 10.

Alternatively, the through hole 1271 provided on the protection member 127 may be provided in various manners, as shown in fig. 7, one through hole 1271 may be provided only in the middle region of the protection member 127, or a plurality of small through holes 1271 having relatively small apertures may be provided on the protection member 127, which is not limited in the embodiment of the present application.

Alternatively, the condensing sheet 122, the air-permeable film 123, the protector 127, etc. in the embodiment of the present application may be fixed to the body 121 in various manners, such as bonding, riveting, welding, etc. For example, when the main body 121, the ventilation film 123, and the protector 127 are made of engineering plastics, the above-mentioned components and the main body 121 may be fixed by hot-melt welding, and when the condensation plate 122 is made of metal, for example, the condensation plate 122 may be fixed in the main body 121 by interference fit. The manner in which the various components are secured to the body 121 in embodiments of the present application may be determined based on the materials used for the components and the requirements, and embodiments of the present application are not limited in this respect.

As an implementation manner, in order to improve the tightness between the pressure balancing mechanism 12 and the battery, as shown in fig. 7 to 9, a sealing ring 13 may be further provided between the battery and the pressure balancing mechanism 12, and specifically, the pressure balancing mechanism 12 further includes: and a sealing ring 13, wherein the sealing ring 13 is arranged at the connection position of the main body 121 and the battery to seal the battery.

The sealing ring 13 provided on the body 121 can be closely attached to the battery after the pressure balance mechanism 12 is fixed to the battery, thereby improving the sealability of the battery.

It should be understood that in addition to the fluid port 1214, the protector 127, and the seal ring 13 provided with the pressure balance mechanism 12 having the piston member 124, the above-described components may be provided in other embodiments of the pressure balance mechanism 12 of the present application, and the embodiments of the present application are not limited thereto.

The above embodiment gives an example of the pressure balance mechanism 12 provided with the piston member 124, and by the piston member 124, the flow path of the gas can be prolonged to some extent, condensation of the gas is achieved, the influence of water vapor in the gas on the battery is reduced, and the safety of the battery is enhanced. Alternatively, the pressure balance mechanism 12 in the embodiment of the present application may also implement condensation of the gas by other forms of structure of the body 121 without using the piston member 124.

As an implementation, fig. 10 shows a schematic structural diagram of a main body 121 in an embodiment of the present application. As shown in fig. 10, the main body 121 in the embodiment of the present application may have a hollow structure, that is, the main body 121 has a hollow passage 1211 therein as shown in fig. 10, wherein the condensation sheet 122 and the air-permeable membrane 123 may be disposed at the second opening 1211b of the passage. Optionally, a protection member 127 may also be provided in an embodiment of the present application. At this time, the gas may enter the channel 1211 from the first opening 1211a and be condensed by the condensing sheet 122 provided at the second opening 1211b, and then may enter the inside of the battery via the gas permeable membrane 123.

The hollow passage 1211 in the above embodiment has a simple structure and a limited condensing effect on the gas, and may be implemented by extending the passage 1211 in order to further improve the condensing effect on the gas.

As another implementation, fig. 11 shows a schematic structural diagram of another body 121 in an embodiment of the present application. As shown in fig. 11, the channel 1211 in the body 121 may be a circuitous S-shaped channel that may be opened through the solid body 121, and similarly, gas may enter the channel 1211 from the first opening 1211a and condense through the condensing tab 122 provided at the second opening 1211b, and may then enter the interior of the cell via the gas permeable membrane 123.

Compared with the hollow channel 1211 in fig. 10, the S-shaped channel 1211 in the embodiment of the application can guide the gas to pass through according to the S-shaped path, so as to further prolong the length of the condensing path of the gas, further enhance the condensing effect of the channel 1211 on the gas, reduce the content of the water vapor entering the battery, and enhance the safety of the battery.

Alternatively, the channel 1211 in embodiments of the application may take other forms, and embodiments of the application are not limited in this regard.

In order to reduce the influence of the external environment on the pressure balance mechanism 12, as an implementation, the pressure balance mechanism 12 in an embodiment of the present application may further include a cover 126 for covering the first opening 1211a and being connected to the main body 121, wherein a third gap is provided between the cover 126 and the first opening 1211a, such that gas enters the channel 1211 through the third gap.

Fig. 12 shows an exploded view of a pressure balancing mechanism 12 provided with a cover 126 in an embodiment of the application.

By providing the cover 126, the channel 1211 can be isolated from the external environment, so that a better condensing effect can be exerted on the gas entering into the channel 1211.

Alternatively, in order to fix the cover 126 to the main body 121, similar to the manner in which the piston member 124 is disposed as described above, the embodiment of the present application may provide a plurality of protrusions 1261 at the edge of the cover 126, and correspondingly, a plurality of notches 1212 may be provided at the edge of the first opening 1211a, and the protrusions 1261 may cooperate with the notches 1212 to fix the cover 126 to the main body 121.

Further, a groove for accommodating the cover 126 may be provided at the first opening 1211a, such as the groove region 1213 shown in fig. 12, and in the embodiment of the present application, the groove region 1213 is also correspondingly circular, taking the cover 126 as an example, or the cover 126 and the groove region 1213 may have other shapes, which is not limited thereto.

Further, in order that gas may enter the channel 1211 via the cover 126, a third gap allowing gas to pass may be provided between the cover 126 and the groove region 1213, alternatively the third gap may be provided in various ways, for example, the radial dimension of the cover 126 may be smaller than the radial dimension of the groove region 1213, so that when the cover 126 is fixed to the body 121, a third gap may be formed between the cover 126 and the groove region 1213 to allow gas to pass. Or alternatively, a notch may be provided directly in cover 126 such that gas may pass from the notch directly into channel 1211, as embodiments of the application are not limited in this respect.

Alternatively, the cover 126 in the embodiment of the present application may be disposed to directly cover the end of the first opening 1211a without being required to be engaged with the groove region 1213 of the body 121, which is not limited thereto.

The body 121 in the embodiment of the present application may have different external configurations, and the body 121 as shown in fig. 6a to 12 has a cylindrical external configuration.

Further, as shown in fig. 13, the body 121 may also include two parts, one part being a head 1215 for fixing the cover 126 or the piston member 124 and the other part being a passage portion 1216 for forming the passage 1211, that is, the body 121 may have a structure like a bolt, which generally has two parts of a head and a screw (a cylindrical portion with external threads), wherein the head 1215 of the body may correspond to the head of the bolt, and the passage portion 1216 of the body 121 may correspond to the screw portion of the bolt, which may be regarded as one bolt structure as the whole body 121.

At this time, the body may be fixed to the case of the battery by providing the screw structure 1217 at the outside of the passage portion 1216 of the body 121, and the installation is more convenient and quick by the screw structure 1217. Or alternatively, the body 121 may have another shape such as a rectangular parallelepiped structure, and in this case, the body 121 may be fixed to the case of the battery by means of bonding, riveting, welding, or the like, to which the embodiment of the present application is not limited. Fig. 13 shows a schematic structural view of another pressure balance mechanism 12 in an embodiment of the present application. As shown in fig. 13, the body 121 may fix the body 121 to the case of the battery through the mounting hole 1215 a.

In order to better condense the gas entering the pressure equalization mechanism 12, as an implementation, the pressure equalization mechanism 12 in an embodiment of the present application may be arranged in the area of the battery where the cooling means are arranged.

Fig. 14a shows a schematic structural view of a battery case 11 according to an embodiment of the present application. Fig. 14b is a detailed view corresponding to position C in fig. 14 a. As shown in fig. 14a and 14b, the case 11 of the battery is provided with a water inlet 113 of a water cooling system for inputting a fluid to a thermal management unit provided inside the case 11, and temperature-controlling the battery cells by the fluid input to the thermal management unit. Generally, the position where the water inlet 113 is provided and the area around the water inlet 113 have a lower temperature, so that the pressure balance mechanism 12 near the water inlet 113 is easier to reach the condensing temperature, thereby accelerating the condensation of the gas entering the channel 1211, reducing the influence of the water vapor entering the inside of the battery on the battery, and enhancing the safety of the battery.

It should be understood that, in the above embodiment, the water inlet 113 is disposed on the side wall of the case 11 as an example, in practical application, the water inlet 113 may also be disposed on the bottom wall of the case 11, as long as the pressure balancing mechanism 12 in the embodiment of the present application is disposed in the surrounding area of the water inlet 113, and the specific disposition positions of the water inlet 113 and the pressure balancing mechanism 12 are not limited in the embodiment of the present application.

The embodiment of the application provides a battery, which comprises a plurality of battery cells 20 and a box 11, wherein the battery cells 20 are accommodated in the box 11; and the pressure balancing mechanism 12 in the foregoing embodiments, wherein the pressure balancing mechanism 12 is provided on the case 11.

An embodiment of the present application further provides an electric device, which may include the battery in the foregoing embodiments, and the electric device is configured to provide electric energy.

Alternatively, the electricity consuming device may be a vehicle 1, a ship or a spacecraft.

Having described the pressure equalization mechanism 12, the battery, and the power utilization device of the embodiment of the present application, the method and apparatus for preparing a battery of the embodiment of the present application will be described below, wherein the foregoing embodiments may be referred to for a portion not described in detail.

Fig. 15 shows a schematic flow chart of a method 300 of preparing a battery in accordance with one embodiment of the application. As shown in fig. 14, the method 300 may include the following steps.

S310, a plurality of battery cells 20 and a case 11 are provided.

As one implementation, a plurality of battery cells 20 are housed within the case 11.

S320, the pressure balancing mechanism 12 is provided.

As one implementation, the pressure balancing mechanism 12 is used for a battery to balance the pressure inside and outside the battery, the pressure balancing mechanism 12 is disposed on the case 11, and the pressure balancing mechanism 12 includes: a body 121, the body 121 having a channel 1211 formed therein, the channel 1211 having a first opening 1211a and a second opening 1211b at both ends thereof, the first opening 1211a for guiding gas to the channel 1211; the condensing sheet 122 is used for covering the second opening 1211b and is fixedly connected with the main body 121, the condensing sheet 122 and the channel 1211 are used for condensing vapor in the gas into condensate, and the condensing sheet 122 is provided with ventilation holes for allowing the gas to pass through; and a gas permeable membrane 123 disposed at a side of the condensation sheet 122 remote from the second opening 1211b and fixedly connected to the main body 121, the gas permeable membrane 123 being for allowing gas to pass therethrough and preventing condensate from passing therethrough.

Fig. 16 shows a schematic block diagram of an apparatus 400 for preparing a battery cell according to an embodiment of the present application. As shown in fig. 15, an apparatus 400 for preparing a battery may include: a first providing module 410 and a second providing module 420.

The first providing module 410 is configured to provide a plurality of battery cells 20 and a case 11, where the plurality of battery cells 20 are accommodated in the case 11.

The second providing module 420 is configured to provide the pressure balancing mechanism 12, where the pressure balancing mechanism 12 is disposed on the box 11, and the pressure balancing mechanism 12 includes: a body 121, the body 121 having a channel 1211 formed therein, the channel 1211 having a first opening 1211a and a second opening 1211b at both ends thereof, the first opening 1211a for guiding gas to the channel 1211; the condensing sheet 122 is used for covering the second opening 1211b and is fixedly connected with the main body 121, the condensing sheet 122 and the channel 1211 are used for condensing vapor in the gas into condensate, and the condensing sheet 122 is provided with ventilation holes for allowing the gas to pass through; and a gas permeable membrane 123 disposed at a side of the condensation sheet 122 remote from the second opening 1211b and fixedly connected to the main body 121, the gas permeable membrane 123 being for allowing gas to pass therethrough and preventing condensate from passing therethrough.

While the application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the application. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

A pressure balancing mechanism for a battery to balance pressure inside and outside the battery, the pressure balancing mechanism comprising:

a body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening;

the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through;

the breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable film is used for enabling gas to pass through and preventing condensate from passing through.
The pressure balancing mechanism of claim 1, further comprising:

a piston member configured to be inserted into the passage via the first opening and fixedly connected with the main body.
The pressure balancing mechanism of claim 2, wherein a first gap is provided between the piston member and the channel to form a flow path for the gas.
A pressure balancing mechanism according to claim 2 or 3, wherein the inner surface of the channel, and/or the outer surface of the piston member is provided with grooves to form the flow path of the gas.
The pressure balance mechanism of claim 4 wherein the grooves are helical.
The pressure balancing mechanism of any one of claims 2 to 5, wherein the piston member comprises a fixed portion and an insertion portion connected, the insertion portion being for insertion into the channel, the fixed portion being for fixed connection with the body, wherein a second gap is provided between the fixed portion and the first opening such that the gas enters the channel through the second gap.
The pressure equalization mechanism of claim 6, wherein an edge of the securing portion is provided with a protrusion and an edge of the body is provided with a notch, the protrusion cooperating with the notch to secure the piston member to the body.
The pressure balancing mechanism of claim 1, further comprising:

a cover for covering the first opening and being connected to the main body, wherein a third gap is provided between the cover and the first opening such that the gas enters the channel through the third gap.
The pressure balancing mechanism of any one of claims 1 to 8, wherein a drain is provided in the channel in communication with the first opening, the drain being for draining the condensate out of the channel.
The pressure balancing mechanism of any one of claims 1 to 9, further comprising:

the protection piece is arranged on one side, far away from the second opening, of the breathable film and is fixedly connected with the main body, the protection piece is used for protecting the breathable film, and the protection piece is provided with a through hole used for enabling gas to pass through.
A battery, comprising:

the battery pack comprises a plurality of battery cells and a box body, wherein the battery cells are accommodated in the box body; and

the pressure balancing mechanism of any one of claims 1 to 10, wherein the pressure balancing mechanism is provided on the tank.
An electrical device, comprising: the battery of claim 11, for providing electrical energy.
A method of making a battery, comprising:

providing a plurality of battery cells and a box body, wherein the battery cells are accommodated in the box body;

Providing a pressure balancing mechanism for the battery is used for balancing the pressure inside and outside the battery, the pressure balancing mechanism is arranged on the box body, and the pressure balancing mechanism comprises:

a body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening;

the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through;

the breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable film is used for enabling gas to pass through and preventing condensate from passing through.
An apparatus for preparing a battery, comprising:

the first providing module is used for providing a plurality of battery monomers and a box body, and the battery monomers are accommodated in the box body;

the second provides the module for provide pressure balance mechanism, be used for the battery is in order to balance the inside and outside pressure of battery, pressure balance mechanism set up in on the box, pressure balance mechanism includes:

A body having a passage formed therein, both ends of the passage having a first opening for guiding a gas to the passage and a second opening;

the condensing sheet is used for covering the second opening and is fixedly connected with the main body, the condensing sheet and the channel are used for condensing vapor in the gas into condensate, and the condensing sheet is provided with air holes for allowing the gas to pass through;

the breathable and breathable film is arranged on one side, far away from the second opening, of the condensing sheet and is fixedly connected with the main body, and the breathable and breathable film is used for enabling gas to pass through and preventing condensate from passing through.