CN215989099U - Battery cell, battery and power consumption device - Google Patents

Abstract

The application discloses battery monomer, battery and power consumption device. The battery cell of this application embodiment includes: the shell comprises a first side plate and a second side plate which are oppositely arranged along a first direction; an electrode assembly received in the case; the pressure relief mechanism is arranged on the first side plate and is used for actuating when the internal pressure of the single battery reaches a threshold value so as to relieve the internal pressure; and an air guide member accommodated in the case and arranged with the electrode assembly in a second direction perpendicular to the first direction. The gas guide member is provided with a passage that communicates with a space between the electrode assembly and the second side plate and a space between the electrode assembly and the first side plate to introduce gas in the space between the electrode assembly and the second side plate into the space between the electrode assembly and the first side plate and act on the pressure relief mechanism. This application can in time release the free internal pressure of battery when battery monomer thermal runaway, improves the security.

Description

Battery cell, battery and power consumption device

Technical Field

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

Background

The battery cell is widely used in electronic devices such as a mobile phone, a notebook computer, a battery car, an electric airplane, an electric ship, an electric toy car, an electric toy ship, an electric toy airplane, an electric tool, and the like. The battery monomer can comprise a cadmium-nickel battery monomer, a hydrogen-nickel battery monomer, a lithium ion battery monomer, a secondary alkaline zinc-manganese battery monomer and the like.

In addition to improving the performance of the battery cell, safety issues are also a considerable problem in the development of battery technology. If the safety problem of the battery cell cannot be guaranteed, the battery cell cannot be used. Therefore, how to enhance the safety of the battery cell is a technical problem to be solved urgently in the battery technology.

SUMMERY OF THE UTILITY MODEL

The application provides a battery monomer, battery and power consumption device, it can improve the security performance.

In a first aspect, an embodiment of the present application provides a battery cell, including:

the shell comprises a first side plate and a second side plate which are oppositely arranged along a first direction;

an electrode assembly accommodated in the case;

the pressure relief mechanism is arranged on the first side plate and is used for actuating when the internal pressure of the single battery reaches a threshold value so as to relieve the internal pressure; and

an air guide member accommodated in the case and arranged with the electrode assembly in a second direction perpendicular to the first direction;

wherein the gas guide member is provided with a passage that communicates with a space between the electrode assembly and the second side plate and a space between the electrode assembly and the first side plate to introduce gas in the space between the electrode assembly and the second side plate into the space between the electrode assembly and the first side plate and act on the pressure relief mechanism.

In the above scheme, when a short circuit or an overcharge occurs, the electrode assembly thermally runaway and releases high-temperature and high-pressure substances, such as high-temperature and high-pressure gas, and a part of the gas enters between the second side plate and the electrode assembly; the channel may guide a flow of gas to introduce the gas between the second side plate and the electrode assembly into a space between the electrode assembly and the first side plate and act on the pressure relief mechanism, the gas acting on and applying pressure to the pressure relief mechanism; along with the increase of gas, the pressure that pressure release mechanism bore is big more, and pressure release mechanism actuates when pressure reaches the threshold value to discharge gas and other high temperature high pressure material to the free outside of battery, thereby in time discharge the free internal pressure of battery, in order to reduce the free explosion of battery, the risk of catching fire, improve the security.

In some embodiments, the opening of the channel facing the first side plate is disposed opposite the pressure relief mechanism in the first direction.

In the above scheme, when electrode assembly thermal runaway and release high temperature high pressure gas, gas strikes on pressure relief mechanism via the passageway to make pressure relief mechanism actuate fast, thereby in time release battery monomer's internal pressure, in order to reduce battery monomer explosion, the risk of catching fire.

In some embodiments, the housing further comprises two third side panels oppositely disposed along a third direction, the third side panel connecting the first side panel and the second side panel, the third direction being perpendicular to the first direction and the second direction. The passage is also communicated with a space between the electrode assembly and the third side plate to introduce gas in the space between the electrode assembly and the third side plate into the space between the electrode assembly and the first side plate and act on the pressure relief mechanism.

In the above scheme, when the electrode assembly is thermally out of control and releases high-temperature and high-pressure gas, a part of the gas enters between the third side plate and the electrode assembly; the channel can also guide the gas flow to introduce the gas between third curb plate and electrode assembly into the space between electrode assembly and the first curb plate, in order to let out gas and other high temperature high pressure material outside the battery monomer to the internal pressure of battery monomer is in time let out, in order to reduce the battery monomer and explode, the risk of catching fire.

In some embodiments, the channel comprises: a concave portion that is recessed with respect to a surface of the air guide member facing the first side plate, and the concave portion is disposed opposite to the pressure relief mechanism in the first direction; a first air vent, one end of which is communicated with the concave part and the other end of which is communicated with the space between the electrode assembly and the second side plate; and a second air-guide hole having one end communicated with the recess and the other end communicated with the space between the electrode assembly and the third side plate.

Among the above-mentioned scheme, the concave part can collect the gas in the first air guide hole and the gas in the second air guide hole to make gas impact on pressure relief mechanism, so that pressure relief mechanism actuates fast, thereby in time release the free internal pressure of battery, in order to reduce the free explosion of battery, the risk of catching fire.

In some embodiments, the channel comprises: a first air guide hole penetrating the air guide member in a first direction to communicate a space between the electrode assembly and the second side plate with a space between the electrode assembly and the first side plate; and a second air guide hole penetrating the air guide member in the third direction, the first air guide hole intersecting and communicating with the second air guide hole to communicate a space between the electrode assembly and the third side plate with the first air guide hole. In the present embodiment, the gas between the electrode assembly and the third side plate can flow to the space between the electrode assembly and the first side plate via the second gas-guide holes and the first gas-guide holes.

In some embodiments, the passage includes a first air guide hole penetrating the air guide member in the second direction and a plurality of second air guide holes provided along a circumferential direction of the first air guide hole and penetrating the frame to communicate the first air guide hole with a space outside the frame. The at least one second air-guide hole communicates a space between the electrode assembly and the first side plate with the first air-guide hole, and the at least one second air-guide hole communicates a space between the electrode assembly and the second side plate with the first air-guide hole. The first gas-guide hole is used for providing an expansion space for the electrode assembly.

In the scheme, the first air guide hole of the air guide member can absorb the expansion of the electrode assembly so as to reduce the pressure on the battery assembly and improve the working performance of the electrode assembly.

In some embodiments, the electrode assembly is plural, the plural electrode assemblies are arranged in the second direction, and an air guide member is disposed between at least adjacent two of the electrode assemblies.

In some embodiments, the electrode assembly includes a positive electrode tab, a negative electrode tab, and a separator separating the positive electrode tab and the negative electrode tab, the electrode assembly being in a wound or laminated structure. The outer surface of the electrode assembly comprises two wide surfaces and two narrow surfaces, the area of the wide surfaces is larger than that of the narrow surfaces, the two wide surfaces are oppositely arranged along the second direction, the two narrow surfaces are oppositely arranged along the third direction, and the third direction is perpendicular to the first direction and the second direction. The air guide member is attached to the broad face in the second direction.

In some embodiments, in the third direction, an edge of the air guide member extends beyond the broad face.

The broad face may press the air guide member when the electrode assembly expands. The embodiment enables the edge of the air guide member to exceed the wide surface, so as to reduce the risk that the edge of the air guide member extrudes the wide surface, reduce stress concentration and improve the performance of the electrode assembly.

In some embodiments, the gas guide member is configured to be capable of compressing when the electrode assembly expands to provide an expansion space for the electrode assembly.

In the above scheme, the air guide member can absorb the expansion of the electrode assembly through compression, so that the pressure applied to the battery assembly is reduced, and the working performance of the electrode assembly is improved.

In some embodiments, the air guide member is bonded to the broad face. The embodiment can also reduce the shaking of the air guide member by fixing the air guide member by the electrode assembly.

In some embodiments, the air guide member is made of a thermally insulating material. When a certain electrode assembly is out of control thermally, the gas guide component can prolong or obstruct thermal diffusion between the electrode assemblies, slow down the generation rate of gas and reduce the explosion risk.

In a second aspect, an embodiment of the present application provides a battery, which includes a case and at least one single battery cell according to any one of the embodiments of the first aspect, where the single battery cell is accommodated in the case.

In a third aspect, an embodiment of the present application provides an electric device, which includes the battery of the second aspect, and the battery is used for providing electric energy.

Drawings

Features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic illustration of a vehicle according to some embodiments of the present application;

fig. 2 is an exploded schematic view of a battery provided in accordance with some embodiments of the present application;

fig. 3 is a schematic structural view of the battery module shown in fig. 2;

fig. 4 is an exploded schematic view of a battery cell provided in some embodiments of the present application;

fig. 5 is a schematic structural view of an electrode assembly of a battery cell provided according to some embodiments of the present application;

fig. 6 is a schematic structural view of an electrode assembly of a battery cell provided in accordance with further embodiments of the present application;

fig. 7 is a schematic cross-sectional view of a battery cell provided in some embodiments of the present application;

fig. 8 is another schematic cross-sectional view of a battery cell provided in some embodiments of the present application;

FIG. 9 is a schematic diagram of the structure of an air guide member of a battery cell provided in some embodiments of the present application;

fig. 10 is an enlarged schematic view of the battery cell shown in fig. 7 at a circle frame a;

fig. 11 is a schematic cross-sectional view of a battery cell provided in accordance with another embodiment of the present application;

FIG. 12 is a cross-sectional schematic view of the air guide member shown in FIG. 11;

fig. 13 is a schematic cross-sectional view of a battery cell provided in accordance with other embodiments of the present application;

FIG. 14 is a cross-sectional schematic view of the air guide member shown in FIG. 13.

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

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof in the description and claims of this application and the description of the figures above, are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different elements and not for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "attached" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

The term "and/or" in this application is only one kind of association relationship describing the associated object, and means that there may be three kinds of relationships, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" in this application generally indicates that the preceding and following associated objects are in an "or" relationship.

In the embodiments of the present application, like reference numerals denote like parts, and a detailed description of the same parts is omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width and other dimensions of the various components in the embodiments of the present application and the overall thickness, length, width and other dimensions of the integrated device shown in the drawings are only exemplary and should not constitute any limitation to the present application.

The appearances of "a plurality" in this application are intended to mean more than two (including two).

In this application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, and the embodiment of the present application is not limited thereto. The battery cell may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application.

Reference to a battery in embodiments 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 module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charging or discharging of battery monomer.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive electrode piece, a negative electrode piece and a separator. The battery cell mainly depends on metal ions to move between the positive pole piece and the negative pole piece to work. The positive pole piece comprises a positive current collector and a positive active substance layer, and the positive active substance layer is coated on the surface of the positive current collector; the positive electrode current collector comprises a positive electrode current collecting portion and a positive electrode lug protruding out of the positive electrode current collecting portion, the positive electrode current collecting portion is coated with a positive electrode active substance layer, and at least part of the positive electrode lug is not coated with the positive electrode active substance layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece comprises a negative pole current collector and a negative pole active substance layer, and the negative pole active substance layer is coated on the surface of the negative pole current collector; the negative current collector comprises a negative current collecting part and a negative electrode lug protruding out of the negative current collecting part, the negative current collecting part is coated with a negative electrode active substance layer, and at least part of the negative electrode lug is not coated with the negative electrode active substance layer. The material of the negative electrode current collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the fuse is not fused when a large current is passed, the number of the positive electrode tabs is multiple and the positive electrode tabs are stacked together, and the number of the negative electrode tabs is multiple and the negative electrode tabs are stacked together. The material of the spacer may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

The battery cell further comprises a housing, and a containing cavity for containing the electrode assembly and the electrolyte is formed inside the housing.

For cells, the main safety hazard comes from the charging and discharging processes, and at the same time, with a suitable ambient temperature design, there are generally at least three protective measures for the cells in order to effectively avoid unnecessary losses. In particular, the protective measures comprise at least a switching element, the selection of a suitable spacer material and a pressure relief mechanism. The switching element is an element that can stop charging or discharging the battery when the temperature or resistance in the battery cell reaches a certain threshold value. The separator is used for separating the positive pole piece and the negative pole piece, and can automatically dissolve the micron-scale (even nano-scale) micropores attached to the separator when the temperature rises to a certain value, so that metal ions cannot pass through the separator, and the internal reaction of the battery monomer is stopped.

The pressure relief mechanism refers to an element or a component that is actuated to relieve the internal pressure or temperature of the battery cell when the internal pressure or temperature reaches a predetermined threshold. The threshold design varies according to design requirements. The threshold may depend on the material of one or more of the positive electrode tab, the negative electrode tab, the electrolyte and the separator in the battery cell. The pressure relief mechanism may take the form of, for example, an explosion-proof valve, a gas valve, a pressure relief valve, a safety valve, or the like, and may specifically take the form of a pressure-sensitive element or configuration, i.e., when the internal pressure or temperature of the battery cell reaches a predetermined threshold, the pressure relief mechanism performs an action or a weak structure provided in the pressure relief mechanism is broken, thereby forming an opening or channel through which the internal pressure or temperature can be relieved.

As used herein, "activate" means that the pressure relief mechanism is activated or activated to a state such that the internal pressure or temperature of the battery cell is vented. The actions generated by the pressure relief mechanism may include, but are not limited to: at least a portion of the pressure relief mechanism ruptures, fractures, is torn or opened, or the like. When the pressure relief mechanism is actuated, high-temperature and high-pressure substances in the battery cells are discharged outwards from the actuated part as emissions. In this way, the cells can be vented under controlled pressure, thereby avoiding potentially more serious accidents.

Reference herein to emissions from the battery cell includes, but is not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gas generated by reaction, flame and the like.

The pressure relief mechanism on the single battery has an important influence on the safety of the single battery. For example, when a short circuit or overcharge occurs, thermal runaway may occur in the battery cell, and the pressure may suddenly rise. In this case, the internal pressure can be released outwards by the actuation of the pressure relief mechanism, so as to prevent the battery cell from exploding and igniting.

The pressure relief mechanism is usually disposed on the housing, and the pressure relief mechanism is activated when the internal pressure of the battery cell reaches a threshold value, so as to discharge high-temperature and high-pressure substances in the housing, thereby achieving the relief of the internal pressure. However, the inventors have found that components within the housing can affect the flow of gases when the cells are thermally out of control. For example, the electrode assembly may block the gas to a certain extent, so that the gas is easily accumulated on the side of the electrode assembly away from the pressure relief mechanism, and the gas cannot be timely exhausted from the pressure relief mechanism, thereby causing a safety risk.

In view of the above, in order to solve the problem that the battery cell is not smooth in exhaust when the battery cell is in thermal runaway, the inventors of the present invention conducted extensive research to design a battery cell, in which an air guide member is disposed inside a housing to rapidly guide air to a pressure relief mechanism when the battery cell is in thermal runaway, so that the air is timely exhausted from the pressure relief mechanism, thereby reducing safety risks.

The technical scheme described in the embodiment of the application is suitable for the battery and the electric device using the battery.

The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool and the like. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle and the like; spacecraft include aircraft, rockets, space shuttles, spacecraft, and the like; electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not specifically limit the above power utilization device.

For convenience of explanation, the following embodiments will be described with an electric device as an example of a vehicle.

Fig. 1 is a schematic structural diagram of a vehicle according to some embodiments of the present disclosure. As shown in fig. 1, a battery 2 is provided inside a vehicle 1, and the battery 2 may be provided at the bottom or the head or the tail of the vehicle 1. The battery 2 may be used for power supply of the vehicle 1, and for example, the battery 2 may serve as an operation power source of the vehicle 1.

The vehicle 1 may further comprise a controller 3 and a motor 4, the controller 3 being adapted to control the battery 2 to power the motor 4, e.g. for start-up, navigation and operational power demands while driving of the vehicle 1.

In some embodiments of the present application, the battery 2 may not only serve as an operating power source of the vehicle 1, but also serve as a driving power source of the vehicle 1, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1.

Fig. 2 is an exploded view of a battery provided in some embodiments of the present application. As shown in fig. 2, the battery 2 includes a case 5 and a battery cell (not shown in fig. 2) accommodated in the case 5.

The case 5 is used for accommodating the battery cells, and the case 5 may have various structures. In some embodiments, the box body 5 may include a first box body portion 51 and a second box body portion 52, the first box body portion 51 and the second box body portion 52 cover each other, and the first box body portion 51 and the second box body portion 52 jointly define a receiving space 53 for receiving the battery cells. The second casing part 52 may be a hollow structure with one open end, the first casing part 51 is a plate-shaped structure, and the first casing part 51 covers the open side of the second casing part 52 to form the casing 5 with the accommodating space 53; the first casing portion 51 and the second casing portion 52 may be hollow structures each having one side opened, and the opening side of the first casing portion 51 may be covered with the opening side of the second casing portion 52 to form the casing 5 having the accommodating space 53. Of course, the first and second casing portions 51 and 52 may be various shapes, such as a cylinder, a rectangular parallelepiped, or the like.

In order to improve the sealing property after the first casing portion 51 and the second casing portion 52 are connected, a sealing member, such as a sealant or a gasket, may be provided between the first casing portion 51 and the second casing portion 52.

Assuming that the first box portion 51 covers the top of the second box portion 52, the first box portion 51 may also be referred to as an upper box cover, and the second box portion 52 may also be referred to as a lower box body.

In the battery 2, one or more battery cells may be provided. If the number of the battery monomers is multiple, the multiple battery monomers can be connected in series or in parallel or in series-parallel, and the series-parallel refers to that the multiple battery monomers are connected in series or in parallel. The plurality of battery monomers can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery monomers is accommodated in the box body 5; of course, a plurality of battery cells may be connected in series or in parallel or in series-parallel to form the battery module 6, and a plurality of battery modules 6 may be connected in series or in parallel or in series-parallel to form a whole and accommodated in the box 5.

Fig. 3 is a schematic structural view of the battery module shown in fig. 2. As shown in fig. 3, in some embodiments, there are a plurality of battery cells 7, and the plurality of battery cells 7 are connected in series or in parallel or in series-parallel to form the battery module 6. A plurality of battery modules 6 are connected in series or in parallel or in series-parallel to form a whole and are accommodated in the case.

The plurality of battery cells 7 in the battery module 6 may be electrically connected to each other by a bus member, so as to realize parallel connection, series connection, or parallel-series connection of the plurality of battery cells 7 in the battery module 6.

Fig. 4 is an exploded view of a battery cell according to some embodiments of the present disclosure.

As shown in fig. 4, the battery cell 7 provided in the embodiment of the present application includes an electrode assembly 10 and a case 20 for accommodating the electrode assembly 10.

The housing 20 may also be used to contain an electrolyte. The housing 20 can take a variety of configurations. For example, the exterior can 20 includes a case 21 and a cap assembly 22. The case 21 has a hollow structure with one side open, and the cap assembly 22 covers the opening of the case 21 and is hermetically connected to form a receiving chamber for receiving the electrode assembly 10 and the electrolyte.

The housing 21 may be in various shapes, such as a cylinder, a rectangular parallelepiped, or the like. The shape of the case 21 may be determined according to the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 is of a cylindrical structure, it may be optionally a cylindrical case; if the electrode assembly 10 has a rectangular parallelepiped structure, a rectangular parallelepiped case may be used.

In some embodiments, the cover assembly 22 includes an end cap 221, and the end cap 221 covers the opening of the housing 21. The end cap 221 may have various structures, for example, the end cap 221 may have a plate-like structure. Illustratively, in fig. 4, the housing 21 has a rectangular parallelepiped structure, the end cap 221 has a plate-like structure, and the end cap 221 covers an opening at the top of the housing 21.

The end cap 221 may be made of an insulating material (e.g., plastic) or a conductive material (e.g., metal).

In some embodiments, the cap assembly 22 may further include an electrode terminal 222, and the electrode terminal 222 is mounted on the end cap 221. The two electrode terminals 222 are defined as a positive electrode terminal and a negative electrode terminal, respectively, and the positive electrode terminal and the negative electrode terminal are each used to be electrically connected to the electrode assembly 10 to output electric power generated from the electrode assembly 10.

In other embodiments, the battery cell 7 includes a case 21 and two cap assemblies 22, the case 21 has a hollow structure with two opposite openings, and the two cap assemblies 22 are correspondingly covered on the two openings of the case 21 and are hermetically connected to form a containing cavity for containing the electrode assembly 10 and the electrolyte. In this structure, two electrode terminals 222 may be provided on one cap assembly 22, and the electrode terminal 222 is not provided on the other cap assembly 22, or one electrode terminal 222 may be provided on each of the two cap assemblies 22.

In the battery cell 7, one or more electrode assemblies 10 may be accommodated in the case 21. Illustratively, in fig. 4, there are two electrode assemblies 10.

Fig. 5 is a schematic structural view of an electrode assembly of a battery cell provided according to some embodiments of the present application; fig. 6 is a schematic structural view of an electrode assembly of a battery cell provided in accordance with other embodiments of the present application.

As shown in fig. 5 and 6, the electrode assembly 10 includes a positive electrode tab 11, a negative electrode tab 12, and a separator 13 separating the positive electrode tab 11 and the negative electrode tab 12, and the electrode assembly 10 has a winding type structure or a lamination type structure.

As shown in fig. 5, in some embodiments, electrode assembly 10 is of a coiled construction. The positive pole piece 11, the negative pole piece 12 and the separator 13 are all in a belt-shaped structure. In the embodiment of the present application, the positive electrode tab 11, the separator 13, and the negative electrode tab 12 may be sequentially stacked and wound for more than two turns to form the electrode assembly 10. The electrode assembly 10 is flat. In preparing the electrode assembly 10, the electrode assembly 10 may be directly wound in a flat shape, or may be wound in a hollow cylindrical structure and flattened into a flat shape after winding.

Fig. 5 shows the outline of the wound electrode assembly 10. The outer surface of the electrode assembly 10 includes two wide faces 14 and two narrow faces 15, the two wide faces 14 being flat faces facing each other, the two narrow faces 15 facing each other, the narrow faces 15 connecting the two wide faces 14. The wide surface 14 is substantially parallel to the winding axis of the electrode assembly 10 and is the largest surface. The broad face 14 may be a relatively flat surface and is not required to be purely planar. The narrow face 15 is at least partially a circular arc face. The broad face 14 has a larger area than the narrow face 15.

In an alternative embodiment, as shown in FIG. 6, the electrode assembly 10 is of a laminated construction. Specifically, the electrode assembly 10 includes a plurality of positive electrode tabs 11 and a plurality of negative electrode tabs 12, the positive electrode tabs 11 and the negative electrode tabs 12 being alternately laminated. In the laminated structure, the positive electrode tab 11 and the negative electrode tab 12 are both in a sheet shape, and the direction of lamination of the positive electrode tab 11 and the negative electrode tab 12 is substantially parallel to the thickness direction of the positive electrode tab 11 and the thickness direction of the negative electrode tab 12.

Fig. 6 shows the profile of the laminated electrode assembly 10. The outer surface of the electrode assembly 10 includes two wide faces 14 and two narrow faces 15, the two wide faces 14 facing each other, the two narrow faces 15 facing each other, and the narrow faces 15 connecting the two wide faces 14. The broad face 14 is the largest area surface. The broad face 14 may be a relatively flat surface and is not required to be purely planar. The broad face 14 has a larger area than the narrow face 15.

Fig. 7 is a schematic cross-sectional view of a battery cell provided in some embodiments of the present application; fig. 8 is another schematic cross-sectional view of a battery cell provided in some embodiments of the present application; FIG. 9 is a schematic diagram of the structure of an air guide member of a battery cell provided in some embodiments of the present application; fig. 10 is an enlarged schematic view of the battery cell shown in fig. 7 at a circle frame a.

As shown in fig. 7 to 10, the battery cell 7 of the embodiment of the present application includes: a casing 20 including a first side plate 211 and a second side plate 23 oppositely disposed in the first direction X; an electrode assembly 10 housed in a case 20; the pressure relief mechanism 30 is arranged on the first side plate 211, and the pressure relief mechanism 30 is actuated when the internal pressure of the battery cell 7 reaches a threshold value so as to relieve the internal pressure; and an air guide member 40 accommodated in the case 20 and arranged with the electrode assembly 10 in a second direction Y perpendicular to the first direction X. Wherein the air guide member 40 is provided with a passage 41, the passage 41 communicating with the space between the electrode assembly 10 and the second side plate 23 and the space between the electrode assembly 10 and the first side plate 211 to introduce the gas in the space between the electrode assembly 10 and the second side plate 23 into the space between the electrode assembly 10 and the first side plate 211 and act on the pressure relief mechanism 30.

The first side plate 211 and the second side plate 23 are two portions of the housing 20 that are oppositely disposed in the first direction X.

When case 21 has a hollow structure with one open end, first side plate 211 may be cap assembly 22, or may be a bottom plate of case 21 located on the side of electrode assembly 10 away from cap assembly 22; in other words, one of the first side plate 211 and the second side plate 23 is the cover assembly 22, and the other of the first side plate 211 and the second side plate 23 is the bottom plate of the case 21.

When the housing 21 has a hollow structure with two open ends, the first side plate 211 and the second side plate 23 may be two cover assemblies 22.

Of course, the first side plate 211 and the second side plate 23 may also be two side plates of the housing 21 that are oppositely disposed.

The pressure relief mechanism 30 may be a part of the first side plate 211, or may be a separate structure from the first side plate 211. For example. The first side plate 211 is provided with a pressure release hole penetrating along the thickness direction of the first side plate, and the pressure release mechanism 30 is fixed to the first side plate 211 by welding or the like and covers the pressure release hole. The pressure relief mechanism 30 seals the pressure relief hole to separate the space on the inner side and the outer side of the first side plate 211, so as to prevent the electrolyte from flowing out through the pressure relief hole during normal operation.

The pressure relief mechanism 30 is configured to be actuated to relieve the internal pressure of the battery cell 7 when the internal pressure reaches a threshold value. When too much gas generated by the battery cell 7 causes the pressure inside the case 21 to rise and reach a threshold value, the pressure relief mechanism 30 performs an action or a weak structure arranged in the pressure relief mechanism 30 is broken, and the gas and other high-temperature and high-pressure substances are released outwards through the opening and the pressure relief hole formed by the broken pressure relief mechanism 30, so that the risk of explosion of the battery cell 7 is reduced.

The pressure relief mechanism 30 may be any of various possible pressure relief structures, which are not limited in this application. For example, the pressure relief mechanism 30 may be a pressure-sensitive pressure relief mechanism configured to be ruptured when the internal air pressure of the battery cell 7 provided with the pressure-sensitive pressure relief mechanism reaches a threshold value.

Illustratively, the relief mechanism 30 is formed with scores, grooves or other structures to reduce the local strength of the relief mechanism 30 and to form weak structures on the relief mechanism 30; when the internal pressure of the battery cell 7 reaches a threshold value, the pressure relief mechanism 30 is ruptured at the weak structure, and the pressure relief mechanism 30 is folded along a portion provided at the ruptured portion and forms an opening to release the high-temperature and high-pressure substance.

The air guide member 40 may be attached to the electrode assembly 10, and may also be attached to the inner wall of the case 20. "attached" means that two members are attached to each other, and the two members may be attached to each other and fixed to each other, or may be simply attached to each other and not fixed to each other. For example, the air guide member 40 may be attached to the inner wall of the electrode assembly 10 or the case 20 by an adhesive.

Of course, other members may be disposed between the air guide member 40 and the electrode assembly 10.

The second direction Y is perpendicular to the first direction X. It should be noted that "perpendicular" does not require absolute perpendicularity, and some deviation is allowed.

The embodiments of the present application may form the channel 41 of the air guide member 40 by removing a portion of the material of the air guide member 40. The shape of the passage 41 is not limited in the present application, and the passage 41 may be formed by providing the air guide member 40 with a recess and/or hole, for example. The channel 41 of the gas guide member 40 is a space not filled with solids, which can allow fluids (e.g., gas and liquid) to flow.

The channel 41 may be in direct communication with the space between the electrode assembly 10 and the first side plate 211, or may be in indirect communication via a hole, gap, or other spatial structure. The channel 41 may directly communicate with the space between the electrode assembly 10 and the second side plate 23, or may indirectly communicate via a hole, gap, or other spatial structure.

The present embodiment does not define the space communicating with the channel 41, and the channel 41 may also communicate with other spaces outside the electrode assembly 10.

In the present embodiment, the opening of the passage 41 need not be disposed opposite the pressure relief mechanism 30, as long as the passage 41 can guide the gas to the pressure relief mechanism 30 when the battery cell 7 thermally runaway. In other words, the opening of the channel 41 may be disposed opposite the relief mechanism 30, or may be disposed offset from the relief mechanism.

The number of the air guide members 40 may be one or more.

The present embodiment does not limit the material of the air guide member 40. For example, the air guide member 40 may be made of a rigid material or may be made of an elastic material. The air guide member 40 may be made of a heat conductive material or may be made of a heat insulating material.

When a short circuit or overcharge occurs, etc., the electrode assembly 10 thermally runaway and releases high-temperature and high-pressure substances, such as high-temperature and high-pressure gas, a part of the gas enters between the second side plate 23 and the electrode assembly 10; the channel 41 may guide the flow of gas to introduce the gas between the second side plate 23 and the electrode assembly 10 into the space between the electrode assembly 10 and the first side plate 211 and act on the pressure relief mechanism 30, the gas acting on the pressure relief mechanism 30 and applying pressure to the pressure relief mechanism 30; with the increase of the gas, the pressure borne by the pressure relief mechanism 30 is higher, and the pressure relief mechanism 30 is actuated when the pressure reaches a threshold value, so as to release the gas and other high-temperature and high-pressure substances to the outside of the battery cell 7, thereby releasing the internal pressure of the battery cell 7 in time, and reducing the risk of explosion and fire of the battery cell 7.

Illustratively, the pressure relief mechanism 30 opens a pressure relief hole upon actuation, and the space between the electrode assembly 10 and the first side plate 211 communicates with the pressure relief hole. The gas between the second side plate 23 and the electrode assembly 10 is discharged to the outside via the passage 41, the space between the electrode assembly 10 and the first side plate 211, and the pressure discharge hole.

In some embodiments, the second side plate 23 is a cover assembly 22. Correspondingly, one end of the housing 21 in the first direction X is provided with an opening. The end cap 221 of the cap assembly 22 is generally connected to the case 21 by welding. When the gas pressure inside the battery increases, the joint of the end cap 221 and the case 21 is more easily broken.

The embodiment of the application can guide the gas between the cover assembly 22 and the electrode assembly 10 to the space between the electrode assembly 10 and the first side plate 211 when the battery cell 7 is out of control due to heat by providing the gas guide member 40 with the channel 41, effectively reduce the increasing rate of the gas pressure between the electrode assembly 10 and the cover assembly 22, reduce the gas accumulated between the electrode assembly 10 and the cover assembly 22, reduce the risk of explosion of the battery cell 7 at the cover assembly 22, and improve the safety performance. The channel 41 can guide gas in between the cap assembly 22 and the electrode assembly 10 to a space between the electrode assembly 10 and the second side plate 23 and make the gas act on the pressure relief mechanism 30, so that the pressure relief mechanism 30 can be actuated in time, high-temperature and high-pressure substances of the battery cell 7 can be quickly released, and the explosion risk is reduced.

In some embodiments, the opening of the channel 41 facing the first side plate 211 is disposed opposite the pressure relief mechanism 30 in the first direction X. In other words, in the first direction X, a projection of the passage 41 facing the opening of the first side plate 211 at least partially overlaps with a projection of the pressure relief mechanism 30.

An end surface of the air guide member 40 facing the first side plate 211 is formed with one or more openings of the passage 41. When the opening of the passage 41 facing the first side plate 211 is plural, at least one opening is disposed opposite to the pressure relief mechanism 30 in the first direction X.

In the present embodiment, when the electrode assembly 10 is thermally runaway and releases high-temperature and high-pressure gas, the gas impacts on the pressure relief mechanism 30 through the channel 41, so that the pressure relief mechanism 30 is rapidly activated, and the internal pressure of the battery cell 7 is timely released, thereby reducing the risk of explosion and fire of the battery cell 7.

In some embodiments, the opening of the channel 41 facing the first side plate 211 is disposed opposite the weakened structure of the pressure relief mechanism 30 in the first direction X.

In some embodiments, the housing 20 further comprises two third side plates 212 oppositely disposed along a third direction Z, the third side plates 212 connecting the first side plate 211 and the second side plate 23, the third direction Z being perpendicular to the first direction X and the second direction Y. The passage 41 is also communicated with the space between the electrode assembly 10 and the third side plate 212 to introduce the gas in the space between the electrode assembly 10 and the third side plate 212 into the space between the electrode assembly 10 and the first side plate 211 and act on the pressure relief mechanism 30.

The two third side plates 212 may be two side plates of the housing 21 that are oppositely disposed in the third direction Z.

When the electrode assembly 10 thermally runaway and releases high-temperature and high-pressure gas, a portion of the gas enters between the third side plate 212 and the electrode assembly 10; the channel 41 may also guide the flow of gas to introduce the gas between the third side plate 212 and the electrode assembly 10 into the space between the electrode assembly 10 and the first side plate 211 to discharge the gas and other high-temperature and high-pressure substances to the outside of the battery cell 7, thereby timely discharging the internal pressure of the battery cell 7 to reduce the risk of explosion and fire of the battery cell 7.

In some embodiments, the housing 20 is a rectangular parallelepiped structure. The housing 20 further includes two fourth side plates 213 oppositely disposed along the second direction Y, and the fourth side plates 213 are connected to the first side plate 211, the second side plate 23, and the third side plate 212.

In some embodiments, the third and fourth side panels 212, 213 are both flat plate structures.

In some embodiments, the electrode assembly 10 is plural, the plural electrode assemblies 10 are arranged in the second direction Y, and the air guide member 40 is disposed between at least adjacent two electrode assemblies 10. Alternatively, an air guide member 40 is disposed between any adjacent two electrode assemblies 10.

In other embodiments, the guide member 40 may be disposed adjacent to the fourth side plate 213.

In some embodiments, the electrode assembly 10 includes a positive electrode sheet, a negative electrode sheet, and a separator separating the positive and negative electrode sheets, the electrode assembly being of a wound or laminated structure. The outer surface of the electrode assembly 10 includes two wide surfaces 14 and two narrow surfaces 15, the area of the wide surfaces 14 is larger than that of the narrow surfaces 15, the two wide surfaces 14 are oppositely disposed in the second direction Y, and the two narrow surfaces 15 are oppositely disposed in the third direction Z, which is perpendicular to the first direction X and the second direction Y. The air guide member 40 is attached to the wide face 14 in the second direction Y.

During charging and discharging of the electrode assembly 10, the electrode sheets may expand in the thickness direction thereof. In the coiled electrode assembly 10 and the laminated electrode assembly 10, the amount of expansion in the direction perpendicular to the wide face 14 (i.e., the second direction Y) is the largest. After the expansion of the electrode assembly 10, the wide surface 14 presses the fourth side plate 213, so that gas is not easily collected between the wide surface 14 and the fourth side plate 213.

The expansion of the electrode assembly 10 in the third direction Z is small, so that the narrow face 15 and the third side plate 212 have a large gap therebetween, and gas accumulation is more likely to occur.

The present embodiment attaches the air guide member 40 to the wide surface 14, and can communicate the channel 41 with the space between the narrow surface 15 and the third side plate 212, so as to guide the air between the narrow surface 15 and the third side plate 212 to the pressure relief mechanism 30 to relieve the pressure in time when the battery cell 7 is out of control thermally.

In some embodiments, the edge of the air guide member 40 extends beyond the broad face 14 in the third direction Z.

The edge of the air guide member 40 may or may not extend beyond the broad face 14 in the first direction X. Alternatively, the air guide member 40 extends beyond the edges of the positive electrode tab 11 and the negative electrode tab 12 in the first direction X.

In the third direction Z, both edges of the air guide member 40 extend beyond the broad face 14. In the second direction Y, the projection of the narrow face 15 at least partially overlaps the projection of the air guide member 40.

When the electrode assembly 10 expands, the wide face 14 presses the air guide member 40. The present embodiment extends the edge of the air guide member 40 beyond the broad face 14 to reduce the risk of the edge of the air guide member 40 pressing against the broad face 14, reduce stress concentration, and improve the performance of the electrode assembly 10.

In some embodiments, the gas guide member 40 is configured to be able to compress when the electrode assembly 10 expands to provide an expansion space for the electrode assembly 10.

The air guide 40 may have some compressibility, and may be an elastic material or a hard material. In the case of hard materials, the channels 41 may reduce the strength of the hard material, allowing it to be somewhat compressible.

The air guide member 40 of the present embodiment can absorb the expansion of the electrode assembly 10 by compression to reduce the pressure to which the electrode assembly 10 is subjected, improving the operation performance of the electrode assembly 10.

In some embodiments, the air guide member 40 may be made of an elastic material, such as a compressible modified polypropylene or rubber, or the like. In other embodiments, the air guide member 40 may also be made of a rigid plastic or mica.

In some embodiments, the air guide member 40 is bonded to the broad face 14. The air guide member 40 may be glued, taped, or otherwise adhered to the broad face 14.

In this embodiment, the air guide member 40 may be installed in the case 21 together with the electrode assembly 10, simplifying the assembly process. This embodiment also reduces the rattling of the air guide member 40 by fixing the air guide member 40 by the electrode assembly 10.

In some embodiments, the air guide member 40 is made of an insulating material. When a certain electrode assembly 10 is thermally out of control, the gas guide member 40 can lengthen or block thermal diffusion between the electrode assemblies 10, slow down the generation rate of gas, and reduce the risk of explosion.

In some embodiments, the air guide member 40 is soaked in the electrolyte for a long period of time, and is also made of a material that is resistant to electrolyte corrosion.

In some embodiments, the battery cell 7 further includes a bottom plate 50, and the bottom plate 50 is disposed between the first side plate 211 and the electrode assembly 10 and serves to support the electrode assembly 10. The bottom bracket plate 50 is provided with a through hole which is communicated with the channel 41 and is arranged opposite to the pressure relief mechanism 30 along the first direction X.

In some embodiments, the channel 41 comprises: a concave portion 411 that is recessed with respect to a surface of the air guide member 40 facing the first side plate 211, and the concave portion 411 is disposed opposite to the pressure relief mechanism 30 in the first direction X; a first air-guide hole 412 having one end communicated with the recess 411 and the other end communicated with a space between the electrode assembly 10 and the second side plate 23; and a second air-guide hole 413 having one end communicated with the recess 411 and the other end communicated with a space between the electrode assembly 10 and the third side plate 212.

The concave portion 411 is recessed from the surface of the air guide member 40 facing the first side plate 211 in a direction away from the first side plate 211. In the first direction X, a projection of the recess 411 at least partially overlaps a projection of the pressure relief mechanism 30.

One or more first gas holes 412 may be provided. One or more second air holes 413 may be provided.

An opening at one end of the first air-guide hole 412 is formed at an end surface of the air guide member 40 facing the second side plate 23 such that the first air-guide hole 412 communicates with a space between the electrode assembly 10 and the second side plate 23. An opening at one end of the second air-guide hole 413 is formed at an end surface of the air guide member 40 facing the third side plate 212 such that the second air-guide hole 413 communicates with a space between the electrode assembly 10 and the third side plate 212.

In the present embodiment, the concave portion 411 may collect gas in the first gas guide hole 412 and gas in the second gas guide hole 413, and make the gas impact on the pressure relief mechanism 30, so that the pressure relief mechanism 30 is quickly activated, and the internal pressure of the battery cell 7 is timely released, so as to reduce the risk of explosion and fire of the battery cell 7.

In some embodiments, the flow area of the recess 411 is larger than the flow area of the first air guide hole 412 and the flow area of the second air guide hole 413.

In some embodiments, the recess 411 is semi-circular.

In some embodiments, each of the first air holes 412 and the second air holes 413 is a plurality, and the plurality of first air holes 412 and the plurality of second air holes 413 are radially distributed around the concave portion 411.

Fig. 11 is a schematic cross-sectional view of a battery cell provided in accordance with other embodiments of the present application; FIG. 12 is a cross-sectional schematic view of the air guide member shown in FIG. 11.

As shown in fig. 11 and 12, in some embodiments, the channel 41 includes: a first air guide hole 412 penetrating the air guide member 40 in the first direction X to communicate a space between the electrode assembly 10 and the second side plate 23 with a space between the electrode assembly 10 and the first side plate 211; and a second air guide hole 413, the second air guide hole 413 penetrating the air guide member 40 in the third direction Z, the first air guide hole 412 intersecting and communicating with the second air guide hole 413 to communicate the space between the electrode assembly 10 and the third side plate 212 with the first air guide hole 412.

One or more first gas holes 412 may be provided. One or more second air holes 413 may be provided.

In the present embodiment, gas between the electrode assembly 10 and the third side plate 212 can flow to a space between the electrode assembly 10 and the first side plate 211 via the second gas-guide holes 413 and the first gas-guide holes 412.

In some embodiments, the first air holes 412 and the second air holes 413 are both multiple, and the multiple first air holes 412 and the multiple second air holes 413 are crossed in the longitudinal direction and the transverse direction.

Fig. 13 is a schematic cross-sectional view of a battery cell provided in accordance with other embodiments of the present application; FIG. 14 is a cross-sectional schematic view of the air guide member shown in FIG. 13.

As shown in fig. 13 and 14, the passage 41 includes a first air guide hole 412 and a plurality of second air guide holes 413, the first air guide hole 412 penetrates the air guide member 40 in the second direction Y, the air guide member 40 includes a frame body 42 disposed around the first air guide hole 412, and the plurality of second air guide holes 413 are disposed in a circumferential direction of the first air guide hole 412 and penetrate the frame body 42 to communicate the first air guide hole 412 with a space outside the frame body 42. At least one second air-guide hole 413 communicates the space between the electrode assembly 10 and the first side plate 211 with the first air-guide hole 412, and at least one second air-guide hole 413 communicates the space between the electrode assembly 10 and the second side plate 23 with the first air-guide hole 412. The first gas holes 412 serve to provide expansion spaces for the electrode assembly 10.

The air guide member 40 is sandwiched between the two electrode assemblies 10, and the two electrode assemblies 10 cover the first air guide hole 412 from both sides.

The frame 42 includes two first beam portions 421 facing each other in the first direction X and two second beam portions 422 facing each other in the third direction Z, and the second beam portions 422 are connected to the two first beam portions 421. The two first beam portions 421 and the two second beam portions 422 enclose the first air-guide hole 412.

Both the first beam portions 421 are provided with second air holes 413. The second air-guide holes 413 of the first beam section 421 adjacent to the second side plate 23 communicate the space between the electrode assembly 10 and the second side plate 23 with the first air-guide holes 412, and the second air-guide holes 413 of the first beam section 421 adjacent to the first side plate 211 communicate the space between the electrode assembly 10 and the first side plate 211 with the first air-guide holes 412.

The second air holes 413 and the first air holes 412 of the two first beam portions 421 are engaged to communicate the space between the electrode assembly 10 and the second side plate 23 with the space between the electrode assembly 10 and the first side plate 211.

The first air-guide hole 412 of the air guide member 40 of the present embodiment can absorb the expansion of the electrode assembly 10 to reduce the pressure applied to the electrode assembly 10, thereby improving the operation performance of the electrode assembly 10.

In some embodiments, the second beam portion 422 is also provided with a second air guide hole 413, and the second air guide hole 413 on the second beam portion 422 communicates the space between the electrode assembly 10 and the third side plate 212 with the first air guide hole 412.

It should be noted that, in the present application, the embodiments and features of the embodiments may be combined with each other without conflict.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the above-described embodiments, or equivalents may be substituted for some of the features of the embodiments, without departing from the spirit or scope of the claims.

Claims (14)

1. A battery cell, comprising:

the shell comprises a first side plate and a second side plate which are oppositely arranged along a first direction;

an electrode assembly housed within the case;

the pressure relief mechanism is arranged on the first side plate and is used for actuating when the internal pressure of the battery monomer reaches a threshold value so as to relieve the internal pressure; and

an air guide member accommodated in the case and arranged with the electrode assembly in a second direction perpendicular to the first direction;

wherein the air guide member is provided with a passage communicating with a space between the electrode assembly and the second side plate and a space between the electrode assembly and the first side plate to introduce gas in the space between the electrode assembly and the second side plate into the space between the electrode assembly and the first side plate and act on the pressure relief mechanism.

2. The battery cell of claim 1, wherein an opening of the channel facing the first side plate is disposed opposite the pressure relief mechanism in the first direction.

3. The battery cell of claim 1, wherein the housing further comprises two third side plates oppositely disposed along a third direction, the third side plate connecting the first side plate and the second side plate, the third direction being perpendicular to the first direction and the second direction;

the channel is also communicated with the space between the electrode assembly and the third side plate so as to lead the gas in the space between the electrode assembly and the third side plate into the space between the electrode assembly and the first side plate and act on the pressure relief mechanism.

4. The battery cell of claim 3, wherein the channel comprises:

a concave portion that is recessed with respect to a surface of the air guide member that faces the first side plate, and that is provided opposite to the pressure relief mechanism in the first direction;

a first air-guide hole, one end of which is communicated with the concave part and the other end of which is communicated with the space between the electrode assembly and the second side plate; and

and a second air hole having one end connected to the recess and the other end connected to a space between the electrode assembly and the third side plate.

5. The cell of claim 3, wherein the channel comprises:

a first air guide hole penetrating the air guide member in the first direction to communicate a space between the electrode assembly and the second side plate with a space between the electrode assembly and the first side plate; and

and a second air guide hole penetrating the air guide member in the third direction, the first air guide hole intersecting and communicating with the second air guide hole to communicate a space between the electrode assembly and the third side plate with the first air guide hole.

6. The battery cell according to claim 3, wherein the passage includes a first air-guide hole and a plurality of second air-guide holes, the first air-guide hole penetrating the air-guide member in the second direction, the air-guide member including a frame body disposed around the first air-guide hole, the plurality of second air-guide holes being disposed along a circumferential direction of the first air-guide hole and penetrating the frame body to communicate the first air-guide hole with a space outside the frame body;

at least one of the second air-guide holes communicating a space between the electrode assembly and the first side plate with the first air-guide hole, at least one of the second air-guide holes communicating a space between the electrode assembly and the second side plate with the first air-guide hole;

the first air guide hole is used for providing an expansion space for the electrode assembly.

7. The battery cell as recited in claim 1, wherein the electrode assembly is plural, the plural electrode assemblies are arranged in the second direction, and the air guide member is provided between at least adjacent two of the electrode assemblies.

8. The battery cell of claim 1,

the electrode assembly comprises a positive electrode piece, a negative electrode piece and a separator for separating the positive electrode piece and the negative electrode piece, and the electrode assembly is of a winding structure or a laminated structure;

the outer surface of the electrode assembly comprises two wide surfaces and two narrow surfaces, the area of the wide surfaces is larger than that of the narrow surfaces, the two wide surfaces are oppositely arranged along the second direction, the two narrow surfaces are oppositely arranged along a third direction, and the third direction is perpendicular to the first direction and the second direction;

the air guide member is attached to the broad face in the second direction.

9. The battery cell as recited in claim 8 wherein, in the third direction, an edge of the air guide member extends beyond the broad face.

10. The battery cell as recited in claim 8 wherein the air guide member is configured to be compressible when the electrode assembly expands to provide an expansion space for the electrode assembly.

11. The battery cell as recited in claim 8 wherein the air guide member is adhered to the broad face.

12. The battery cell as recited in claim 1 wherein the air guide member is made of a heat insulating material.

13. A battery comprising a case and at least one cell as claimed in any one of claims 1 to 12, said cell being housed in said case.

14. An electrical device comprising a battery as claimed in claim 13 for providing electrical energy.

Images