Patent Description:
A battery cell is widely used in an electronic device, such as a mobile phone, a notebook computer, an electromobile, an electric vehicle, an electric airplane, an electric ship, an electric toy car, an electric toy ship, an electric toy airplane, and an electric tool. The battery cell may include a nickel-cadmium battery cell, a nickel-hydrogen battery cell, a lithium-ion battery cell, a secondary alkaline zinc-manganese battery cell, and the like.

In the development of battery technology, in addition to improving performance of the battery cell, safety is also an issue that cannot be ignored. If the safety of the battery cell cannot be ensured, the battery cell cannot be used. Therefore, how to enhance the safety of the battery cell is an urgent technical problem to be solved in the battery technology.

From <CIT> there is known a battery cell as defined in the preamble of claim <NUM>.

Embodiments of the present application provide a battery cell and a manufacturing method and manufacturing system thereof, a battery, and a power consumption apparatus, which could enhance safety of the battery cell.

According to a first aspect of the present application, an embodiment of the present application provides a battery cell, as defined in claim <NUM>, including an electrode assembly, a housing, a pressure relief mechanism, and a cover assembly. The housing is provided with an accommodating space for accommodating the electrode assembly, where the housing includes a first side plate located on a side in a first direction; the pressure relief mechanism is disposed on the first side plate; and the cover assembly is configured for sealing the housing, where an inner surface of the first side plate of the housing is provided with a first flow channel extending along the inner surface, and the first flow channel is configured to guide a gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated when a pressure reaches a threshold, and relieve the pressure. The first flow channel includes a first intermediate flow channel and a first edge flow channel, the first edge flow channel extends along a circumferential edge of the inner surface of the first side plate and communicates with the accommodating space, and the first edge flow channel and the pressure relief mechanism are in communication through the first intermediate flow channel.

In the above solution, in the embodiment of the present application, a first flow channel is disposed on a first side plate of a housing, and the first flow channel includes a first intermediate flow channel and a first edge flow channel. When a battery cell releases a gas during thermal runaway, the first edge flow channel can guide the gas to flow from an accommodating space along an edge of the housing and move to the first intermediate flow channel, and then guide the gas to a pressure relief mechanism through the first intermediate flow channel, so that the pressure relief mechanism is actuated in time and relieves the gas, so as to improve an exhaust rate during the thermal runaway of the battery cell, and improve safety of the battery cell.

In some embodiments, the first intermediate flow channel includes a first intermediate groove disposed on the inner surface of the first side plate, one end of the first intermediate groove communicates with the pressure relief mechanism, and the other end of the first intermediate groove communicates with the first edge flow channel. When thermal runaway occurs in the battery cell, the released gas can be guided from the accommodating space to the pressure relief mechanism along the first intermediate groove to be discharged, which will not affect gas exhausting due to blockage of the electrode assembly, increases an exhaust rate during the thermal runaway of the battery cell, and improves safety of the battery cell. At the same time, the first intermediate groove is disposed on the inner surface of the first side plate so as not to occupy the accommodating space and thus energy density of the battery cell is not affected.

In some embodiments, there are a plurality of the first intermediate grooves, and each of the first intermediate grooves communicates with the pressure relief mechanism and the first edge flow channel.

In some embodiments, at least two of the first intermediate grooves are parallel to each other, which is beneficial to improve exhaust efficiency in a length direction of the first intermediate grooves. Alternatively, the plurality of first intermediate grooves extend to a periphery in a divergent shape with the pressure relief mechanism as a center, which is beneficial to improve exhaust efficiency in a circumferential direction of the pressure relief mechanism.

In some embodiments, the first edge flow channel includes a first edge groove disposed at a circumferential edge of the inner surface of the first side plate and extending along the circumferential edge, and each of the first intermediate grooves communicates with the first edge groove. By setting the first edge groove, the gas can move to the nearest first intermediate groove through the first edge groove and be guided to the pressure relief mechanism to be discharged, which shortens a movement path of the gas, makes gas exhausting smoother, and improves exhaust efficiency. In addition, if a certain one of the first intermediate grooves is blocked, the gas can also move to another first intermediate groove through the first edge groove to be discharged, which improves reliability of gas exhausting.

In some embodiments, the first edge groove is an annulus or a notched annulus, or the first edge groove includes a plurality of sub-grooves spaced apart along the circumferential edge.

In some embodiments, a first protruding part protruding toward the accommodating space is formed on the inner surface of the first side plate, the first protruding part has a top surface away from the inner surface, and the first intermediate flow channel and the first edge flow channel are formed in a space between the top surface of the first protruding part and the inner surface. In this embodiment, the top surface of a first protruding part is used to support the electrode assembly, and the first intermediate flow channel and the first edge flow channel are formed in the space between the top surface of the first protruding part and the inner surface, which will not affect gas exhausting due to blockage of the electrode assembly, increases the exhaust rate during the thermal runaway of the battery cell, and improves the safety of the battery cell.

In some embodiments, the first intermediate flow channel includes a plurality of first intermediate sub-flow channels; there are a plurality of the first protruding parts, the plurality of first protruding parts extend to a periphery in a divergent shape with the pressure relief mechanism as a center, and one of the first intermediate sub-flow channels is formed between two adjacent first protruding parts and the inner surface of the first side plate; the housing includes a pair of second side plates disposed opposite to each other in a second direction perpendicular to the first direction; the housing further includes a pair of third side plates disposed opposite to each other in a third direction perpendicular to the first direction and the second direction; and a gap is disposed between an end of each of the first protruding parts away from the pressure relief mechanism and an adjacent second side plate or an adjacent third side plate, and the gap forms a portion of the first edge flow channel. By setting the plurality of first protruding parts that extend to the periphery in the divergent shape with the pressure relief mechanism as the center, the first intermediate flow channel and the first edge flow channel are formed, which can improve exhaust efficiency in the circumferential direction of the pressure relief mechanism. In addition, if a certain one of the first intermediate sub-flow channels is blocked, the gas can also move to another first intermediate sub-flow channel through the first edge flow channel to be discharged, which improves the reliability of gas exhausting.

In some embodiments, an insulating layer is disposed on the top surface of the first protruding part, the insulating layer is configured to realize insulation between the electrode assembly and the housing, and there is no need to provide an additional support member, which reduces occupation of the space, and is beneficial to improve energy density of the battery cell without affecting the gas exhausting of the battery cell.

In some embodiments, starting from a position where the first intermediate flow channel communicates with the pressure relief mechanism, a depth of at least a portion of a length of the first intermediate flow channel gradually decreases in a direction away from the pressure relief mechanism. Further, a depth of at least a portion of a length of the first intermediate flow channel gradually increases in a direction close to the pressure relief mechanism, so as to form a slope inclined toward the gas exhausting direction of the pressure relief mechanism, which is more beneficial to guide the gas to the pressure relief mechanism to be discharged, and improves exhaust efficiency.

In some embodiments, a support member is disposed between the first side plate and the electrode assembly to support the electrode assembly, where the support member has a first surface and a second surface disposed opposite to each other, the first surface faces the first side plate, and the second surface faces the electrode assembly; and a second flow channel is disposed on the first surface of the support member; and the first intermediate flow channel and the accommodating space are in communication through the second flow channel. The second flow channel is formed on the support member so that the first intermediate flow channel and the accommodating space are in communication, which can increase a cross-sectional area of a flow channel of gas exhausting, and improve exhaust efficiency.

In some embodiments, the second flow channel matches the first flow channel in shape. The shape of the second flow channel matches the shape of the first flow channel, and after combination, the cross-sectional area of the flow channel of gas exhausting can be increased, and the exhaust efficiency can be improved.

In some embodiments, the support member includes a first through hole penetrating the support member in the first direction, and the first intermediate flow channel and the accommodating space are in communication through the first through hole.

In some embodiments, an insulating film is further included to wrap a portion of the electrode assembly and separate the electrode assembly and the housing, where the insulating film includes a first side film located between the electrode assembly and the support member; and the first side film includes a second through hole penetrating the first side film in the first direction, and a projection of the second through hole does not overlap with a projection of the first through hole on the first direction. The projection of the second through hole of the first side film of the insulating film does not overlap with the projection of the first through hole of the support member in the first direction, which can achieve reliable insulation between the electrode assembly and the first side plate, enable the second through hole of the first side film of the insulating film to be matched with the first through hole of the support member, allow the gas in the accommodating space to enter the pressure relief mechanism through the second through hole, the first through hole and the first intermediate flow channel to be discharged, and improve exhaust efficiency of the inner space of the insulating film.

According to a second aspect of the present application, there is provided a battery including the battery cell of the first aspect.

According to a third aspect of the present application, there is provided a power consumption apparatus including the battery of the second aspect.

In some embodiments, the power consumption apparatus is a vehicle, a ship or a spacecraft.

According to a fourth aspect of the present application, there is provided a manufacturing method of a battery cell, including: providing an electrode assembly; providing a housing, where the housing is provided with an accommodating space for accommodating the electrode assembly; and the housing includes a first side plate located on a side in a first direction; providing a pressure relief mechanism disposed on the first side plate; providing a cover assembly for sealing the housing; and assembling the electrode assembly, the housing, the pressure relief mechanism and the cover assembly to form the battery cell, where the providing the housing includes forming on an inner surface of the first side plate of the housing a first flow channel extending along the inner surface, and the first flow channel is configured to guide a gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated when a pressure reaches a threshold, and relieves the pressure; and the first flow channel includes a first intermediate flow channel and a first edge flow channel, the first edge flow channel extends along a circumferential edge of the inner surface of the first side plate and communicates with the accommodating space, and the first edge flow channel and the pressure relief mechanism are in communication through the first intermediate flow channel.

According to a fifth aspect of the present application, there is provided a manufacturing system of a battery cell, including: an electrode assembly providing apparatus for providing an electrode assembly; a housing providing apparatus for providing a housing, where the housing is provided with an accommodating space for accommodating the electrode assembly; and the housing includes a first side plate located on a side in a first direction; a pressure relief mechanism providing apparatus for providing a pressure relief mechanism, where the pressure relief mechanism is disposed on the first side plate; a cover assembly providing apparatus for providing a cover assembly for sealing the housing; and an assembly apparatus for assembling the electrode assembly, the housing, the pressure relief mechanism and the cover assembly to form the battery cell, where an inner surface of the first side plate of the housing is provided with a first flow channel extending along the inner surface, and the first flow channel is configured to guide a gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated when a pressure reaches a threshold, and relieves the pressure; and the first flow channel includes a first intermediate flow channel and a first edge flow channel, the first edge flow channel extends along a circumferential edge of the inner surface of the first side plate and communicates with the accommodating space, and the first edge flow channel and the pressure relief mechanism are in communication through the first intermediate flow channel.

According to a battery cell and a manufacturing method and manufacturing system thereof, a battery and a power consumption apparatus provided by the present application, exhaust efficiency can be improved during thermal runaway of the battery cell, and safety of the battery cell can be improved.

The accompanying drawings described herein are used to provide further understanding of the present application and constitute a part of the present application, and exemplary embodiments of the present application and description thereof are used to explain the present application and do not constitute an undue limitation to the present application. In the drawings:.

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

To make the objectives, technical solutions and advantages of embodiments of the present application clearer, the following clearly describes the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are merely some but not all of the embodiments of the present application. All the other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without any inventive effort shall fall within the scope of protection of the present application.

Unless otherwise defined, all technical and scientific terms used in the present application have the same meanings as those commonly understood by those skilled in the art in the technical field to which the present application belongs. Terms used in the specification of the present application are merely for the purpose of describing specific embodiments, but are not intended to limit the present application. Terms "comprising" and "having" as well as any variation thereof in the specification and the claims as well as the foregoing description of the accompanying drawings of the present application are intended to cover non-exclusive inclusions. Terms "first", "second", and the like in the specification and the claims or the above drawings of the present application are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

Phrase "embodiments" referred to in the present application means that specific features, structures or characteristics described in combination with embodiments can be included in at least one embodiment of the present application. The phrase at various locations in the specification does not necessarily refer to the same embodiment, or an independent or alternative embodiment exclusive of another embodiment.

In the description of the present application, it should be noted that unless otherwise explicitly specified and defined, terms "mounting", "connecting", "connection" and "attaching" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integrated connection; and it may be a direct connection, an indirect connection via an intermediate medium, or communication between the interiors of two elements. Those of ordinary skill in the art may understand specific meanings of the foregoing terms in the present application according to specific situations.

In the present application, term "and/or" is only an association relation describing associated objects, which means that there may be three relations. For example, A and/or B may represent three situations: A exists alone, both A and B exist, and B exists alone. In addition, a character "/" in the present application generally indicates that associated objects before and after the character are in an "or" relation.

In the embodiments of the present application, same components are denoted by same reference numerals, and detailed description of the same components is omitted in different embodiments for brevity. It should be understood that dimensions such as thicknesses, lengths and widths of various components in embodiments of the present application shown in the drawings, as well as dimensions such as the overall thickness, length and width of an integrated apparatus are merely illustrative, and should not constitute any limitation to the present application.

In the present application, phrase "a plurality of" means two or more (including two).

In the present application, a 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, etc., which is not limited by the embodiment of the present application. The battery cell may be cylindrical, flat, cuboid or in other shapes, which is not limited by the embodiment of the present application. The battery cell is generally divided into three types according to the way of packaging: a cylindrical battery cell, a prismatic battery cell and a pouch battery cell, which is also not limited by the embodiment of the present application.

A battery mentioned in an embodiment of the present application refers to a single physical module that includes one or more battery cells to provide a higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module, a battery pack, or the like. The battery generally includes a box for enclosing one or more battery cells. The box can prevent a liquid or other foreign matters from affecting the charging or discharging of the battery cell.

The battery cell includes an electrode assembly and an electrolyte, and the electrode assembly includes a positive electrode plate, a negative electrode plate and a separator. The operation of the battery cell mainly relies on movement of metal ions between the positive electrode plate and the negative electrode plate. The positive electrode plate includes a positive electrode current collector and a positive active substance layer, and the positive active substance layer is coated on a surface of the positive electrode current collector. The positive electrode current collector includes a positive electrode current collecting part and a positive electrode protruding part protruding from the positive electrode current collecting part, the positive electrode current collecting part is coated with the positive active substance layer, at least part of the positive electrode protruding part is not coated with the positive active substance layer, and the positive electrode protruding part is used as a positive tab. In an example of a lithium-ion battery, the material of the positive electrode current collector may be aluminum, the positive active substance layer includes a positive active substance, and the positive active substance may be lithium cobalt oxide, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative electrode plate includes a negative electrode current collector and a negative active substance layer, and the negative active substance layer is coated on a surface of the negative electrode current collector. The negative electrode current collector includes a negative electrode current collecting part and a negative electrode protruding part protruding from the negative electrode current collecting part, the negative electrode current collecting part is coated with the negative active substance layer, at least part of the negative electrode protruding part is not coated with the negative active substance layer, and the negative electrode protruding part is used as a negative tab. The material of the negative electrode current collector may be copper, the negative active substance layer includes a negative active substance, and the negative active substance may be carbon or silicon, or the like. In order to ensure that no fusing occurs when a large current passes, positive tabs are plural in number and are stacked together, and negative tabs are plural in number and are stacked together. The material of the separator may be polypropylene (PP), polyethylene (PE), or the like. In addition, the electrode assembly may be in a winding structure or a laminated structure, and the embodiment of the present application is not limited thereto.

The battery cell may further include a housing assembly, and the housing assembly has an accommodating cavity inside, and the accommodating cavity is a closed space provided by the housing assembly for the electrode assembly and the electrolyte.

For the battery cell, a main safety hazard comes from charging and discharging processes, and a suitable ambient temperature design is also required. In order to avoid unnecessary loss effectively, at least triple protection measures are generally taken for the battery cell. Specifically, the protection measures at least include a switching element, a properly selected separator material and a pressure relief mechanism. The switching element refers to an element that may stop charging or discharging of a battery when a temperature or a resistance of the battery cell reaches a certain threshold. The separator is configured to separate a positive electrode plate and a negative electrode plate and can automatically dissolve micron-sized (or even nano-sized) micro-pores attached to the separator when temperature rises to a certain value, so that metal ions are prevented from passing through the separator and an internal reaction of the battery cell is terminated.

The pressure relief mechanism refers to an element or a part that is actuated when an internal pressure of the battery cell reaches a predetermined threshold, to relieve the internal pressure. The threshold design varies according to different design requirements. The threshold may depend on the material of one or more of the positive electrode plate, the negative electrode plate, the electrolytic solution and the separator in the battery cell. The pressure relief mechanism may take the form of an explosion-proof valve, an air valve, a pressure relief valve or a safety valve, etc., and may specifically adopt a pressure-sensitive element or structure. That is, when the internal pressure of the battery cell reaches the predetermined threshold, the pressure relief mechanism performs an action or a weakened structure disposed in the pressure relief mechanism is fractured, so as to form an opening or a channel for relieving the internal pressure or temperature.

The word "actuated" mentioned in the present application means that the pressure relief mechanism performs an action or is activated to a certain state, so that the internal pressure of the battery cell can be relieved. The action performed by the pressure relief mechanism may include but be not limited to: at least a portion of the pressure relief mechanism is fractured, broken, torn or opened, and so on. When the pressure relief mechanism is actuated, high temperature and high pressure substances inside the battery cell are discharged to the outside from an actuated position as emissions. In this way, the pressure of the battery cell can be relieved under a controllable pressure, so as to avoid potentially more serious accidents.

The emissions from the battery cell mentioned in the present application include but are not limited to: the electrolytic solution, dissolved or split positive and negative electrode plates, fragments of the separator, a high temperature and high pressure gas generated by reaction, flame, and the like.

The pressure relief mechanism on the battery cell has an important impact on the safety of the battery cell. For example, when short circuit, overcharge and other phenomena occur, it may lead to thermal runaway inside the battery cell and a further sudden increase in pressure. In this case, the internal pressure can be released to the outside through the actuation of the pressure relief mechanism, so as to prevent the battery cell from exploding and catching fire.

The pressure relief mechanism is usually mounted in the housing assembly. The inventors found that, in order to improve energy density of the battery cell, a space for gas flow inside the battery cell is limited, which results in a low rate of gas exhausting during thermal runaway. In addition, the pressure relief mechanism may be shielded by a component inside the housing assembly, which results in poor exhaust and a potential safety hazard.

In view of this, an embodiment of the present application provides a technical solution. In the technical solution, a battery cell includes an electrode assembly, a housing, a pressure relief mechanism and a cover assembly. Specifically, the housing is provided with an accommodating space for accommodating the electrode assembly; the housing includes a first side plate located on a side in a first direction; the pressure relief mechanism is disposed on the first side plate; and the cover assembly is configured for sealing the housing, where an inner surface of the first side plate of the housing is provided with a first flow channel extending along the inner surface, and the first flow channel is configured to guide a gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated when a pressure reaches a threshold, and relieves the pressure. The first flow channel includes a first intermediate flow channel and a first edge flow channel, the first edge flow channel extends along a circumferential edge of the inner surface of the first side plate and communicates with the accommodating space, and the first edge flow channel and the pressure relief mechanism are in communication through the first intermediate flow channel. The battery cell having this structure guides a high temperature and high pressure gas to the pressure relief mechanism during thermal runaway, so as to increase an exhaust rate and improve safety performance.

The technical solution described in the embodiment of the present application is applicable to a battery and a power consumption apparatus using the battery.

The power consumption apparatus may be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, and so on. The vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle; the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended range vehicle, etc.; the spacecraft includes an airplane, a rocket, a space shuttle and a spaceship, etc.; the electric toy includes a fixed or mobile electric toy, such as a game console, an electric vehicle toy, an electric ship toy and an electric airplane toy, etc.; the electric tool includes a metal cutting power tool, a grinding power tool, an assembly power tool and a railway power tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, an electric planer, etc. The above power consumption apparatus is not specially limited in the embodiment of the present application.

For convenience of description, the following embodiments are explained by an example that the power consumption apparatus is a vehicle.

<FIG> is a schematic structural diagram of a vehicle provided by some embodiments of the present application. As shown in <FIG>, an interior of a vehicle <NUM> is provided with a battery <NUM>, and the battery <NUM> may be disposed at the bottom, head or tail of the vehicle <NUM>. The battery <NUM> may be used for power supply of the vehicle <NUM>. For example, the battery <NUM> may serve as an operation power supply of the vehicle <NUM>.

The vehicle <NUM> may further include a controller <NUM> and a motor <NUM>. The controller <NUM> is used to control the battery <NUM> to supply power to the motor <NUM>, for example, for starting, navigating, and working power requirements during driving of the vehicle <NUM>.

In some embodiments of the present application, the battery <NUM> may serve not only as an operation power source of the vehicle <NUM>, but also as a driving power source of the vehicle <NUM>, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle <NUM>.

<FIG> is a schematic exploded view of a battery provided by some embodiments of the present application. As shown in <FIG>, a battery <NUM> includes a box <NUM> and a battery cell (not shown in <FIG>), and the battery cell is accommodated in the box <NUM>.

The box <NUM> is configured to accommodate the battery cell, and the box <NUM> may have various structures. In some embodiments, the box <NUM> may include a first box portion <NUM> and a second box portion <NUM>, the first box portion <NUM> and the second box portion <NUM> are covered with each other, and the first box portion <NUM> and the second box portion <NUM> together define an accommodating space <NUM> for accommodating the battery cell. The second box portion <NUM> may be a hollow structure with one side open, the first box portion <NUM> is a plate-like structure, and the first box portion <NUM> covers an opening side of the second box portion <NUM> to form the box <NUM> having the accommodating space <NUM>. The first box portion <NUM> and the second box portion <NUM> may also both be a hollow structure with one side open, and an opening side of the first box portion <NUM> covers an opening side of the second box portion <NUM> to form the box <NUM> having the accommodating space <NUM>. Of course, the first box portion <NUM> and the second box portion <NUM> may have various shapes, such as a cylinder, a cube, or the like.

In order to improve the airtightness after the first box portion <NUM> and the second box portion <NUM> are connected, a sealing member, such as a sealant, a sealing ring, or the like, may also be disposed between the first box portion <NUM> and the second box portion <NUM>.

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

In the battery <NUM>, the battery cell may be one or plural in number. If the battery cell is plural in number, a plurality of battery cells may be connected in series or in parallel or in series and parallel. The series and parallel connection means that the plurality of battery cells are connected in series and in parallel. The plurality of battery cells may be directly connected in series or in parallel or in series and parallel, and then a whole formed by the plurality of battery cells may be accommodated in the box <NUM>. Of course, the plurality of battery cells may also be first connected in series or in parallel or in series and parallel to form a battery module <NUM>, and then a plurality of battery modules <NUM> are connected in series or in parallel or in series and parallel to form a whole, and are accommodated in the box <NUM>.

<FIG> is a schematic structural diagram of the battery module shown in <FIG>. As shown in <FIG>, in some embodiments, there are a plurality of battery cells <NUM>, and the plurality of battery cells <NUM> are first connected in series or in parallel or series and parallel to form the battery module <NUM>. A plurality of battery modules <NUM> are then connected in series or in parallel or in series and parallel to form a whole, and are accommodated in the box.

The plurality of battery cells <NUM> in the battery module <NUM> may be electrically connected through a bus component to realize the parallel, or series or series and parallel connection of the plurality of battery cells <NUM> in the battery module <NUM>.

<FIG> is a schematic exploded view of a battery cell provided by some embodiments of the present application.

As shown in <FIG>, a battery cell <NUM> provided by the embodiments of the present application includes an electrode assembly <NUM> and a housing assembly <NUM>, and the electrode assembly <NUM> is accommodated in the housing assembly <NUM>.

In some embodiments, the battery cell <NUM> includes an electrode assembly <NUM>, a housing <NUM>, a pressure relief mechanism <NUM> and a cover assembly <NUM>. The housing <NUM> is provided with an accommodating space <NUM> for accommodating the electrode assembly <NUM>; the housing <NUM> includes a first side plate <NUM> located on a side in a first direction Z; the pressure relief mechanism <NUM> is disposed on the first side plate <NUM>; and the cover assembly <NUM> is configured for sealing the housing <NUM>, where an inner surface <NUM> of the first side plate <NUM> of the housing <NUM> is provided with a first flow channel extending along the inner surface <NUM>, and the first flow channel is configured to guide a gas in the accommodating space <NUM> to the pressure relief mechanism <NUM> so that the pressure relief mechanism <NUM> is actuated when a pressure reaches a threshold, and relieves the pressure.

In some embodiments, the housing assembly <NUM> may be further configured to accommodate an electrolyte, such as an electrolytic solution. The housing assembly <NUM> may be in a form of a variety of structures.

In some embodiments, the housing assembly <NUM> may include the housing <NUM> and the cover assembly <NUM>. The housing <NUM> is a hollow structure with one side open. The cover assembly <NUM> covers an opening of the housing <NUM> and forms a sealed connection to form an accommodating cavity for accommodating the electrode assembly <NUM> and an electrolyte.

The housing <NUM> may have various shapes, such as a cylinder, a cube, or the like. The shape of the housing <NUM> may be determined according to a specific shape of the electrode assembly <NUM>. For example, if the electrode assembly <NUM> has a cylindrical structure, a cylindrical housing may be selected; and if the electrode assembly <NUM> has a cuboid structure, a cuboid housing may be selected.

In some embodiments, the cover assembly <NUM> includes an end cover <NUM>, and the end cover <NUM> covers an opening of the housing <NUM>. The end cover <NUM> may have various structures, for example, the end cover <NUM> has a plate-shaped structure. Illustratively, in <FIG>, the housing <NUM> has a cuboid structure, the end cover <NUM> has a plate-shaped structure, and the end cover <NUM> covers an opening at the top of the housing <NUM>.

The end cover <NUM> may be made of an insulating material (such as plastic), or may be made of a conductive material (such as metal). When the end cover <NUM> is made of a metal material, the cover assembly <NUM> may further include an insulating plate located on a side of the end cover <NUM> facing the electrode assembly <NUM> to insulate and separate the end cover <NUM> from the electrode assembly <NUM>.

In some embodiments, the cover assembly <NUM> may further include an electrode terminal <NUM> mounted on the end cover <NUM>. There are two electrode terminals <NUM>, and the two electrode terminals <NUM> are defined as a positive electrode terminal and a negative electrode terminal respectively. Both the positive electrode terminal and the negative electrode terminal are configured to be electrically connected to the electrode assembly <NUM> to output electric energy generated by the electrode assembly <NUM>.

In some further embodiments, the housing assembly <NUM> may also have another structure. For example, the housing assembly <NUM> includes a housing <NUM> and two cover assemblies <NUM>. The housing <NUM> is a hollow structure with an opening on two opposite sides. One cover assembly <NUM> correspondingly covers an opening of the housing <NUM> and forms a sealed connection to form an accommodating cavity for accommodating the electrode assembly <NUM> and the electrolyte. In this structure, one cover assembly <NUM> may be provided with two electrode terminals <NUM> while the other cover assembly <NUM> may not be provided with the electrode terminal <NUM>, or each of the two cover assemblies <NUM> may be provided with one electrode terminal <NUM>.

In the battery cell <NUM>, the electrode assembly <NUM> accommodated in the housing assembly <NUM> may be one or plural. Illustratively, in <FIG>, there are two electrode assemblies <NUM>.

The electrode assembly <NUM> includes a positive electrode plate, a negative electrode plate and a separator. The electrode assembly <NUM> may be a winding electrode assembly, a laminated electrode assembly, or another form of electrode assembly.

In some embodiments, the electrode assembly <NUM> is a winding electrode assembly. A positive electrode plate, a negative electrode plate and a separator are all in a strip-shaped structure. In the embodiments of the present application, the positive electrode plate, the separator and the negative electrode plate can be stacked in sequence and wound for more than two turns to form the electrode assembly <NUM>.

In some further embodiments, the electrode assembly <NUM> is a laminated electrode assembly. Specifically, the electrode assembly <NUM> includes a plurality of positive electrode plates and a plurality of negative electrode plates, the positive electrode plates and the negative electrode plates are alternately stacked, and a stacking direction is parallel to a thickness direction of the positive electrode plates and a thickness direction of the negative electrode plates.

From the perspective of the outer shape of the electrode assembly <NUM>, the electrode assembly <NUM> includes a main body part <NUM> and a tab part <NUM> connected to the main body part <NUM>. Illustratively, the tab part <NUM> extends from an end of the main body part <NUM> close to the cover assembly <NUM>.

In some embodiments, there are two tab parts <NUM>, and the two tab parts <NUM> are defined as a positive tab part and a negative tab part respectively. The positive tab part and the negative tab part may extend from the same end of the main body part <NUM>, or may extend from opposite ends of the main body part <NUM> respectively.

The main body part <NUM> is a core portion of the electrode assembly <NUM> to realize a charging and discharging function, and the tab part <NUM> is configured to draw out current generated by the main body part <NUM>. The main body part <NUM> includes a positive electrode current collecting part of a positive electrode current collector, a positive active substance layer, a negative electrode current collecting part of a negative electrode current collector, a negative active substance layer, and a separator. The positive tab part includes a plurality of positive tabs, and the negative tab part includes a plurality of negative tabs.

The tab part <NUM> is configured to be electrically connected to the electrode terminal <NUM>. The tab part <NUM> may be directly connected to the electrode terminal <NUM> by means of welding for example, or may be indirectly connected to the electrode terminal <NUM> through another member. For example, the battery cell <NUM> further includes a current collecting member <NUM> for electrically connecting the electrode terminal <NUM> and the tab part <NUM>. There are two current collecting members <NUM>, and the two current collecting members <NUM> are defined as a positive electrode current collecting member and a negative electrode current collecting member respectively. The positive electrode current collecting member is configured to electrically connect the positive electrode terminal and the positive tab part, and the negative electrode current collecting member is configured to electrically connect the negative electrode terminal and the negative tab part. When the battery cell <NUM> is provided with a plurality of electrode assemblies <NUM>, positive electrode current collecting members of the plurality of electrode assemblies <NUM> may be integrally configured, and negative electrode current collecting members of the plurality of electrode assemblies <NUM> may be integrally configured.

The first side plate <NUM> is located on a side of the housing assembly <NUM> in the first direction Z. The housing <NUM> of the housing assembly <NUM> has an end opening on the other side in the first direction Z opposite to the first side plate <NUM>.

When the housing <NUM> is a hollow structure with one end open, the first side plate <NUM> is a bottom plate of the housing <NUM> located on a side of the electrode assembly <NUM> away from the cover assembly <NUM>.

The pressure relief mechanism <NUM> is disposed on the first side plate <NUM>. The pressure relief mechanism <NUM> may be a portion of the first side plate <NUM>, or may be a separate structure from the first side plate <NUM>. The first side plate <NUM> is provided with a first pressure relief hole <NUM> penetrating in a thickness direction of the first side plate <NUM>, and the pressure relief mechanism <NUM> is fixed on the first side plate <NUM> by means of welding or the like and covers the first pressure relief hole <NUM>. The pressure relief mechanism <NUM> seals the first pressure relief hole <NUM> to separate a space between inner and outer sides of the first side plate <NUM>, which prevents an electrolyte from flowing out through the first pressure relief hole <NUM> during normal operation.

The pressure relief mechanism <NUM> is configured to be actuated when an internal pressure of the battery cell <NUM> reaches a threshold, to relieve the internal pressure. When a gas generated by the battery cell <NUM> is too much so that the internal pressure of the housing <NUM> rises and reaches the threshold, the pressure relief mechanism <NUM> performs an action or a weakened structure disposed in the pressure relief mechanism <NUM> is fractured, and the gas and other high temperature and high pressure substances are released to the outside through a fractured opening of the pressure relief mechanism <NUM> and the first pressure relief hole <NUM>, thereby preventing the battery cell <NUM> from exploding.

The pressure relief mechanism <NUM> may have various possible pressure relief structures, which is not limited by the embodiments of the present application. For example, the pressure relief mechanism <NUM> may be a pressure-sensitive pressure relief mechanism configured to be fractured when an internal air pressure of the battery cell <NUM> provided with the pressure-sensitive pressure relief mechanism reaches a threshold.

In some embodiments, an indentation, a groove or another structure is formed on the pressure relief mechanism <NUM> to reduce local strength of the pressure relief mechanism <NUM> and form a weakened structure on the pressure relief mechanism <NUM>. When an internal pressure of the battery cell <NUM> reaches a threshold, the pressure relief mechanism <NUM> is fractured at the weakened structure, and the pressure relief mechanism <NUM> is folded along a part provided at the fractured position and forms an opening so as to release high temperature and high pressure substances.

When short-circuit, overcharge and other phenomena occur, thermal runaway occurs in the battery cell <NUM> and a large amount of high temperature and high pressure substances such as a high temperature and high pressure gas are released. The first flow channel can guide the gas to flow, so as to guide the gas in the accommodating space <NUM> to the pressure relief mechanism <NUM>, and the gas acts on a pressure bearing surface of the pressure relief mechanism <NUM> and applies pressure to the pressure relief mechanism <NUM>. As the gas increases, the pressure the pressure relief mechanism <NUM> bears becomes greater, and the pressure relief mechanism <NUM> is actuated when the pressure reaches the threshold, to relieve the gas and other high temperature and high pressure substances to the outside of the battery cell <NUM>, thereby releasing the internal pressure of the battery cell <NUM> to the outside, and preventing the battery cell <NUM> from exploding and catching fire.

In the embodiments of the present application, by setting the first flow channel on the first side plate <NUM> of the housing <NUM>, the gas released by the battery cell <NUM> during thermal runaway can be guided from the accommodating space <NUM> to the pressure relief mechanism <NUM>, so that the pressure relief mechanism <NUM> is actuated in time and relieves the gas, so as to increase an exhaust rate during the thermal runaway of the battery cell <NUM>, and improve safety of the battery cell <NUM>.

<FIG> is a schematic structural diagram of a housing of a battery cell provided by some embodiments of the present application; <FIG> is a schematic top view of a battery cell provided by some embodiments of the present application; <FIG> is a schematic cross-sectional view of the battery cell shown in <FIG> using the housing of the embodiment of <FIG> at B-B; <FIG> is a schematic enlarged view of the battery cell shown in <FIG> at C; <FIG> is a schematic enlarged view of the battery cell shown in <FIG> at D; <FIG> is a schematic cross-sectional view of the battery cell shown in <FIG> using the housing of the embodiment of <FIG> at E-E; and <FIG> is a schematic enlarged view of the battery cell shown in <FIG> at F.

Referring to <FIG>, in some embodiments, the first flow channel includes a first intermediate flow channel <NUM> and a first edge flow channel <NUM>, the first edge flow channel <NUM> extends along a circumferential edge of the inner surface <NUM> of the first side plate <NUM> and communicates with the accommodating space <NUM>, and the first edge flow channel <NUM> and a pressure relief mechanism <NUM> are in communication through the first intermediate flow channel <NUM>.

In some embodiments, the first intermediate flow channel <NUM> includes a first intermediate groove <NUM> extending on the inner surface <NUM>, one end of each first intermediate groove <NUM> communicates with the pressure relief mechanism <NUM>, and the other end of each first intermediate groove <NUM> communicates with the first edge flow channel <NUM>. When thermal runaway occurs in the battery cell <NUM>, the released gas can be guided from the accommodating space <NUM> to the pressure relief mechanism <NUM> along the first intermediate groove <NUM> to be discharged, which will not affect gas exhausting due to blockage of the electrode assembly <NUM>, increases an exhaust rate during the thermal runaway of the battery cell <NUM>, and improves safety of the battery cell <NUM>. At the same time, the first intermediate groove <NUM> is disposed on the inner surface <NUM> of the first side plate <NUM> so as not to occupy the accommodating space <NUM> and thus energy density of the battery cell <NUM> is not affected.

In some embodiments, the first intermediate flow channel <NUM> includes a plurality of the first intermediate grooves <NUM>, and each of the first intermediate grooves <NUM> communicates with the pressure relief mechanism <NUM> and the first edge flow channel <NUM>. The plurality of first intermediate grooves <NUM> can improve the exhaust rate during the thermal runaway of the battery cell <NUM>, and improve the safety of the battery cell <NUM>. At the same time, even if a certain one of the first intermediate grooves <NUM> is blocked, the gas can also move to another first intermediate groove <NUM> through the first edge flow channel <NUM> and then be discharged by the pressure relief mechanism <NUM>, which improves reliability of gas exhausting. Furthermore, the first intermediate groove <NUM> is disposed on the inner surface of the first side plate <NUM> so as not to occupy the accommodating space <NUM> and thus energy density of the battery cell <NUM> is not affected.

In some embodiments, the plurality of first intermediate grooves <NUM> on the housing <NUM> extend to a periphery in a divergent shape with the pressure relief mechanism <NUM> as a center.

Specifically, the plurality of first intermediate grooves <NUM> together form the first intermediate flow channel <NUM>, and the plurality of first intermediate grooves <NUM> extend to the periphery in the divergent shape with the pressure relief mechanism <NUM> as the center. Extending in the divergent shape means that the plurality of first intermediate grooves <NUM> are centered on the pressure relief mechanism <NUM>, and the plurality of first intermediate grooves <NUM> extend approximately in a radial direction with a center of the pressure relief mechanism <NUM> as an axis. Ends of the plurality of first intermediate grooves <NUM> communicate with the pressure relief mechanism <NUM>. In some embodiments, the plurality of first intermediate grooves <NUM> are connected to the first pressure relief hole <NUM>. The other ends of a portion of the first intermediate grooves <NUM> extend to the vicinity of an adjacent second side plate <NUM>, and the other ends of a portion of the first intermediate grooves <NUM> extend to the vicinity of a third side plate <NUM>.

In some embodiments, the first edge flow channel <NUM> includes a first edge groove <NUM> disposed at a circumferential edge of the inner surface <NUM> of the first side plate <NUM> and extending along the circumferential edge, and each of the first intermediate grooves <NUM> communicates with the first edge groove <NUM>. By setting the first edge groove <NUM>, the gas can move to the nearest first intermediate groove <NUM> through the first edge groove <NUM> and be guided to the pressure relief mechanism <NUM> to be discharged, which shortens a movement path of the gas, makes gas exhausting smoother, and improves exhaust efficiency. In addition, if a certain first intermediate groove <NUM> is blocked, the gas can also move to another first intermediate groove <NUM> through the first edge groove <NUM> to be discharged, which improves the reliability of gas exhausting. In some embodiments, the first edge groove <NUM> is an integrally communicated annulus.

Referring to <FIG>, the housing <NUM> includes a pair of second side plates <NUM> disposed opposite to each other in a third direction Y, and a pair of third side plates <NUM> disposed opposite to each other in a second direction X. Both the second side plates <NUM> and the third side plates <NUM> are connected to the first side plate <NUM>, and the second side plates <NUM> and the third side plates <NUM> adjacent to each other are also connected together to form the accommodating space <NUM>. The second direction X is perpendicular to the first direction Z and the third direction Y. The third direction Y is perpendicular to the first direction Z and the second direction X.

Referring to <FIG>, in the embodiment, the accommodating space <NUM> includes a first gap G1 disposed between the electrode assembly <NUM> and each of the second side plates <NUM>, and a portion of the first edge grooves <NUM> extending to the vicinity of the adjacent second side plate <NUM> communicate with the first gap G1. The accommodating space <NUM> further includes a second gap G2 disposed between the electrode assembly <NUM> and each of the third side plates <NUM>, and a portion of the first edge grooves <NUM> extending to the vicinity of the third side plate <NUM> communicate with the second gap G2. In this way, when thermal runaway occurs in the battery cell <NUM>, the gas can be guided to the first intermediate groove <NUM> along the first edge groove <NUM> through the first gap G1 and the second gap G2 respectively in the circumferential direction of the first side plate <NUM>, and then move to the pressure relief mechanism <NUM> through the first intermediate groove <NUM>. In addition, the gas generated inside the electrode assembly <NUM> can also enter the pressure relief mechanism <NUM> directly through the first intermediate groove <NUM>, which increases the exhaust rate during the thermal runaway of the battery cell <NUM>, and improves the safety of the battery cell <NUM>.

Referring to <FIG>, the accommodating space <NUM> includes a first gap G1 disposed between the electrode assembly <NUM> and each of the second side plates <NUM>. The first edge groove <NUM> communicates with the first gap G1. The first intermediate groove <NUM> communicates with the first gap G1 through the first edge groove <NUM>, thereby realizing communication between the first intermediate flow channel <NUM> and the accommodating space <NUM> through the first edge flow channel <NUM>.

Referring to <FIG>, in some embodiments, starting from a position where the first intermediate flow channel <NUM> communicates with the pressure relief mechanism <NUM>, a depth H of at least a portion of a length of the first intermediate flow channel <NUM> gradually decreases in a direction away from the pressure relief mechanism <NUM>.

Specifically, starting from the position where the first intermediate flow channel <NUM> communicates with the pressure relief mechanism <NUM>, in at least the portion of the length of each first intermediate groove <NUM> constituting the first intermediate flow channel <NUM> in the third direction Y, the depth H of the first intermediate groove <NUM> gradually decreases in the direction away from the pressure relief mechanism <NUM>. Referring to <FIG>, a depth H of at least a portion of a length of the first intermediate groove <NUM> gradually increases in a direction close to the pressure relief mechanism <NUM>, so as to form a slope inclined toward the gas exhausting direction of the pressure relief mechanism <NUM>, which is more beneficial to guide the gas to the pressure relief mechanism <NUM> to be discharged, and improves exhaust efficiency. The slope may be inclined in a straight line or in an arc.

The portion of the length means that the portion where the depth H changes only occupies a portion of the length of the first intermediate flow channel <NUM> that is connected to the pressure relief mechanism <NUM> in the third direction Y, and a depth of the remaining portion of the length of the first intermediate flow channel <NUM> can remain unchanged. In some further embodiments, the first intermediate flow channel <NUM> may also have a change in the depth H over the entire length of the first intermediate flow channel <NUM>.

The position where the first intermediate flow channel <NUM> communicates with the pressure relief mechanism <NUM> refers to a position where the first intermediate flow channel <NUM> is connected to an edge of the pressure relief mechanism <NUM>. When the housing <NUM> is provided with a first pressure relief hole <NUM>, the position where the first intermediate flow channel <NUM> communicates with the pressure relief mechanism <NUM> refers to a position where the first intermediate flow channel <NUM> is connected to the first pressure relief hole <NUM>.

Referring to <FIG> and <FIG>, a second gap G2 is disposed between the electrode assembly <NUM> and each of the third side plates <NUM>, and the first edge groove <NUM> communicates with the second gap G2. The first intermediate groove <NUM> communicates with the second gap G2 through the first edge groove <NUM>, thereby realizing communication between the first intermediate flow channel <NUM> and the accommodating space <NUM> through the first edge flow channel <NUM>. Furthermore, when a gas generated by the battery cell <NUM> is too much so that the internal pressure of the housing <NUM> rises and reaches a threshold, after the gas passes through the second gap G2, it can move to the pressure relief mechanism <NUM> through the plurality of first intermediate grooves <NUM> to be discharged without being blocked by the electrode assembly <NUM>.

In addition, in some embodiments, the gas generated inside the electrode assembly <NUM> can also enter the pressure relief mechanism <NUM> directly through the first intermediate flow channel <NUM>.

<FIG> is a schematic structural diagram of a housing of a battery cell provided by another embodiment of the present application.

Referring to <FIG>, in this embodiment, difference from the housing <NUM> in the embodiment of <FIG> lies in that the plurality of first intermediate grooves <NUM> constituting the first intermediate flow channel <NUM> include at least two first intermediate grooves <NUM> parallel to each other. As shown in <FIG>, the first intermediate flow channel <NUM> includes two first intermediate grooves <NUM> extending in the third direction Y and two first intermediate grooves <NUM> extending in the second direction X. Each of the first intermediate grooves <NUM> communicates with the pressure relief mechanism <NUM> and the first edge groove <NUM>. The number of the first intermediate grooves <NUM> is not limited to two, and the extending direction thereof is also not limited to the third direction Y or the second direction X.

Referring to <FIG>, in this embodiment, difference from the housing <NUM> in the embodiment of <FIG> lies in that the first edge groove <NUM> is not continuously disposed, but is a notched annulus, or the first edge groove <NUM> includes a plurality of sub-grooves spaced apart along the circumferential edge, and each sub-groove communicates with the pressure relief mechanism <NUM> through the first intermediate groove <NUM>.

<FIG> is a schematic structural diagram of a housing of a battery cell provided by another embodiment of the present application; and <FIG> is a schematic partially enlarged view of a schematic cross-sectional view of the battery cell shown in <FIG> using the housing of the embodiment of <FIG> at E-E.

Referring to <FIG> and <FIG>, in some embodiments, in the housing <NUM>, a first protruding part <NUM> protruding toward the accommodating space <NUM> is formed on the inner surface of the first side plate <NUM>, the first protruding part <NUM> has a top surface <NUM> away from the inner surface <NUM>, and the first intermediate flow channel <NUM> and the first edge flow channel <NUM> are formed in a space between the top surface <NUM> of the first protruding part <NUM> and the inner surface <NUM>. In this embodiment, the top surface <NUM> of the first protruding part <NUM> is used to support the electrode assembly <NUM>, and the first intermediate flow channel <NUM> and the first edge flow channel <NUM> are formed in the space between the top surface <NUM> of the first protruding part <NUM> and the inner surface <NUM>, which can increase the exhaust rate during the thermal runaway of the battery cell <NUM>, and improves the safety of the battery cell <NUM>.

In some embodiments, as shown in <FIG>, the first intermediate flow channel <NUM> includes a plurality of first intermediate sub-flow channels <NUM> communicating with the pressure relief mechanism <NUM>; there are a plurality of the first protruding parts <NUM>, the plurality of first protruding parts <NUM> extend to a periphery in a divergent shape with the pressure relief mechanism <NUM> as a center and are spaced apart from each other, and one of the first intermediate sub-flow channels <NUM> is formed between two adjacent first protruding parts <NUM> and the inner surface <NUM>. A fifth gap G5 is disposed between an end of each of the first protruding parts <NUM> away from the pressure relief mechanism <NUM> and an adjacent second side plate <NUM> or an adjacent third side plate <NUM>, and the fifth gap G5 forms a portion of the first edge flow channel <NUM>. By setting the plurality of first protruding parts <NUM> that extend to the periphery in the divergent shape with the pressure relief mechanism <NUM> as the center, the first intermediate flow channel <NUM> and the first edge flow channel <NUM> are formed, which can improve exhaust efficiency in the circumferential direction of the pressure relief mechanism <NUM>. By setting the fifth gap G5, the gas can also move along a circumferential direction of an edge of the first side plate <NUM> to form the first edge flow channel <NUM>. In addition, if a certain one of the first intermediate sub-flow channels <NUM> is blocked, the gas can also move to another first intermediate sub-flow channel <NUM> through the first edge flow channel <NUM> to be discharged, which improves the reliability of gas exhausting.

Specifically, one of the first intermediate sub-flow channels <NUM> is formed between two adjacent first protruding parts <NUM> and the inner surface <NUM>, and the plurality of first intermediate sub-flow channels <NUM> extend to the periphery in the divergent shape with the pressure relief mechanism <NUM> as the center and are spaced apart from each other. Extending in the divergent shape means that the plurality of first intermediate sub-flow channels <NUM> are centered on the pressure relief mechanism <NUM>, and the plurality of first intermediate sub-flow channels <NUM> extend approximately in a radial direction with a center point of the pressure relief mechanism <NUM> as an axis. Ends of the plurality of first intermediate sub-flow channels <NUM> communicate with the pressure relief mechanism <NUM>. In some embodiments, the plurality of first intermediate sub-flow channels <NUM> are connected to the first pressure relief hole <NUM>. The other ends of a portion of the first intermediate sub-flow channels <NUM> extend to the vicinity of one second side plate <NUM> and communicate with the first gap G1, and the other ends of a portion of the first intermediate sub-flow channels <NUM> extend to the vicinity of one third side plate <NUM> and communicate with the second gap G2. The adjacent first intermediate sub-flow channels <NUM> can also communicate with each other through the fifth gap G5.

Referring to <FIG> and <FIG>, in this embodiment, the accommodating space <NUM> includes the first gap G1 disposed between the electrode assembly <NUM> and each of the second side plates <NUM>, and a portion of the first intermediate flow sub-channels <NUM> extending to the vicinity of one second side plate <NUM> communicate with the first gap G1. The accommodating space <NUM> further includes the second gap G2 disposed between the electrode assembly <NUM> and each of the third side plates <NUM>, and a portion of the first intermediate sub-flow channels <NUM> extending to the vicinity of one third side plate <NUM> communicate with the second gap G2. In this way, when thermal runaway occurs in the battery cell <NUM>, the gas can be guided to the pressure relief mechanism <NUM> along the first intermediate flow channel <NUM> in the circumferential direction of the pressure relief mechanism <NUM>, so as to improve the exhaust efficiency during the thermal runaway of the battery cell <NUM>, and improve the safety of the battery cell <NUM>. In addition, if a certain one of the first intermediate sub-flow channels <NUM> is blocked, the gas can also move to another first intermediate sub-flow channel <NUM> through the first edge flow channel <NUM> to be discharged, which improves the reliability of gas exhausting.

In addition, in some embodiments, the gas generated inside the electrode assembly <NUM> can also enter the pressure relief mechanism <NUM> directly through the first intermediate sub-flow channel <NUM>.

In addition, in the embodiments of <FIG>, or referring to the embodiment of <FIG>, starting from a position where the first intermediate flow channel <NUM> communicates with the pressure relief mechanism <NUM>, a depth H of at least a portion of a length of the first intermediate flow channel <NUM> gradually decreases in a direction away from the pressure relief mechanism <NUM>.

In the above embodiments, an insulating layer may also be disposed on the top surface <NUM> of the first protruding part <NUM>, the insulating layer is configured to realize insulation between the electrode assembly <NUM> and the housing <NUM>, and there is no need to provide an additional support member, which reduces occupation of the accommodating space <NUM>, and is beneficial to improve energy density of the battery cell <NUM> without affecting the gas exhausting of the battery cell <NUM>.

<FIG> is a schematic structural diagram of a battery cell provided by another embodiment of the present application.

Referring to <FIG>, this embodiment differs from the above embodiments in that a support member <NUM> is added. The support member <NUM> is disposed between the electrode assembly <NUM> and the first side plate <NUM> and configured to support the electrode assembly <NUM>. The electrode assembly <NUM>, the support member <NUM> and the first side plate <NUM> are arranged in order in the first direction Z. Illustratively, the support member <NUM> is made of an insulating material capable of insulating the first side plate <NUM> from the electrode assembly <NUM>. The support member <NUM> can support the electrode assembly <NUM> to reduce shaking of the electrode assembly <NUM> when the battery cell <NUM> vibrates, and reduce the risk of falling off of active substances of the electrode assembly <NUM>.

The support member <NUM> may directly abut against the electrode assembly <NUM> to support the electrode assembly <NUM>, or may support the electrode assembly <NUM> through another member. For example, the battery cell <NUM> further includes an insulating film <NUM> coating an outer side of the main body part <NUM> of the electrode assembly <NUM>, a portion of the insulating film <NUM> is located between the support member <NUM> and the electrode assembly <NUM>, and the support member <NUM> supports the electrode assembly <NUM> through the insulating film <NUM>. The support member <NUM> has a first surface <NUM> and a second surface <NUM> disposed opposite to each other, the first surface <NUM> faces the first side plate <NUM>, and the second surface <NUM> faces the electrode assembly <NUM>.

In some embodiments, the support member <NUM> may abut against the first side plate <NUM>, for example, in the embodiments of <FIG>, the support member <NUM> may abut against the first side plate <NUM> under the gravity of the electrode assembly <NUM>, and is in contact with the inner surface <NUM> of the first side plate <NUM>. Referring to <FIG>, a third gap G3 is disposed between the support member <NUM> and the third side plate <NUM> in the third direction Y, and referring to the embodiment in <FIG>, a fourth gap G4 is disposed between the support member <NUM> and the adjacent second side plate <NUM> in the second direction X. The first gap G1 communicates with the first edge flow channel <NUM> through the third gap G3. The second gap G2 communicates with the first edge flow channel <NUM> through the fourth gap G4.

The support member <NUM> may also be spaced apart from the first side plate <NUM> in the first direction Z. For example, in the embodiments of <FIG> and <FIG>, the support member <NUM> may be placed on the surface of the first protruding part <NUM> and spaced apart from the inner surface <NUM> of the first side plate <NUM>.

<FIG> is a schematic structural diagram of a support member of a battery cell provided by another embodiment of the present application; <FIG> is a schematic structural diagram of a support member of a battery cell provided by another embodiment of the present application; and <FIG> is a schematic structural diagram of a support member of a battery cell provided by another embodiment of the present application.

In some embodiments, a second flow channel is disposed on the support member <NUM>, and the first intermediate flow channel <NUM> and the accommodating space <NUM> are in communication through the second flow channel. The second flow channel is formed on the support member <NUM> so that the first intermediate flow channel <NUM> and the accommodating space <NUM> are in communication, which can increase a flow channel area of gas exhausting, and improve exhaust efficiency.

Referring to <FIG>, in some embodiments, the second flow channel includes a first through hole <NUM> penetrating the support member <NUM> in the first direction Z, and the first intermediate flow channel <NUM> and the accommodating space <NUM> are in communication through the first through hole <NUM> in the first direction Z. By means of the first through hole <NUM>, the gas generated inside the electrode assembly <NUM> can pass through the support member <NUM> through the first through hole <NUM> and enter the first intermediate flow channel <NUM> directly, which can improve exhaust efficiency.

Referring to <FIG>, in some embodiments, the second flow channel matches the first flow channel in shape. The shape of the second flow channel matches the shape of the first flow channel, and after combination, a cross-sectional area of the flow channel of gas exhausting can be increased, and exhaust efficiency can be improved. Specifically, the shape of the second flow channel matches shapes of the first intermediate flow channel <NUM> and the first edge flow channel <NUM>, and after the combination, the cross-sectional area of the flow channel of gas exhausting can be increased, and the exhaust efficiency can be improved.

In some embodiments, the second flow channel includes a second intermediate flow channel <NUM> disposed on the first surface <NUM>, the second intermediate flow channel <NUM> communicates with the first gap G1 and/or the second gap G2, and the second intermediate flow channel <NUM> has the same shape as the first intermediate flow channel <NUM>. The support member <NUM> is provided with the second intermediate flow channel <NUM> communicating with the first gap G1 and/or the second gap G2 and the first intermediate flow channel <NUM>, so that the flow channel area of gas exhausting can be increased and the exhaust efficiency can be improved.

In some embodiments, a second pressure relief hole <NUM> is disposed on the support member <NUM>, and a position of the second pressure relief hole <NUM> corresponds to that of the first pressure relief hole <NUM> on the housing <NUM>. The second intermediate flow channel <NUM> extends to a periphery in a divergent shape with the second pressure relief hole <NUM> as a center. The second pressure relief hole <NUM> and the first gap G1 and/or the second gap G2 are in communication through the second intermediate flow channel <NUM>.

In some embodiments, a peripheral edge of the support member <NUM> is further provided with a second edge flow channel <NUM>, and a shape of the second edge flow channel <NUM> is the same as that of the first edge flow channel <NUM>. The flow channel area of gas exhausting at the edge of the first side plate <NUM> can be increased, and the exhaust efficiency can be improved.

Referring to <FIG>, in some embodiments, the first through hole <NUM>, the second intermediate flow channel <NUM> and the second edge flow channel <NUM> are disposed on the support member <NUM>, and the first through hole <NUM> communicates with the second intermediate flow channel <NUM>. The flow channel area of gas exhausting can be further increased and the exhaust efficiency is improved.

<FIG> is a schematic structural diagram of a battery cell provided with a support member and an insulating film provided by another embodiment of the present application; and <FIG> is a schematic structural diagram of an insulating film shown by another embodiment of the present application.

Referring to <FIG>, in some embodiments, the battery cell <NUM> further includes an insulating film <NUM> coating an outer side of the main body part <NUM> of the electrode assembly <NUM>, a portion of the insulating film <NUM> is located between the support member <NUM> and the electrode assembly <NUM>, and the support member <NUM> supports the electrode assembly <NUM> through the insulating film <NUM>. The support member <NUM> has a first surface <NUM> and a second surface <NUM> disposed opposite to each other, the first surface <NUM> faces the first side plate <NUM>, and the second surface <NUM> faces the insulating film <NUM>.

In some embodiments, the insulating film <NUM> is configured to wrap a portion of the electrode assembly <NUM> and separate the electrode assembly <NUM> and the housing <NUM>; the insulating film <NUM> includes a first side film <NUM> located between the electrode assembly <NUM> and the support member <NUM>; and the first side film <NUM> has a second through hole <NUM>, and a projection of the second through hole <NUM> does not overlap with projections of the first through hole <NUM> and the second pressure relief hole <NUM> of the support member <NUM> on the first direction Z. The projection of the second through hole <NUM> of the first side film <NUM> of the insulating film <NUM> does not overlap with the projections of the first through hole <NUM> and the second pressure relief hole <NUM> on the support member <NUM> in the first direction Z, which can avoid that the electrode assembly <NUM> and the first side plate <NUM> of the housing <NUM> are in direct contact, and realize communication between the accommodating space <NUM> and the first intermediate flow channel <NUM> through the first through hole <NUM> and the second through hole <NUM> while achieving reliable insulation between the electrode assembly <NUM> and the first side plate <NUM>. Therefore, exhaust efficiency is improved.

In some embodiments, referring to <FIG> and <FIG>, the first side film <NUM> is located on one side of the insulating film <NUM> in the first direction Z. The insulating film <NUM> is provided with third side films <NUM> disposed opposite to each other in the third direction Y, and an opening <NUM> is disposed at a position of the third side film <NUM> close to the first side film <NUM>. The gas generated in the electrode assembly <NUM> wrapped by the insulating film <NUM> can be connected to the first intermediate flow channel <NUM> through the second through hole <NUM> and the first through hole <NUM> on one hand, and can be connected to the first edge flow channel <NUM> through the opening <NUM> as well as the first gap G1 and the third gap G3 on the other hand, and further be discharged through the pressure relief mechanism <NUM>, which can increase the flow channel area of gas exhausting and improve the exhaust efficiency.

<FIG> is a schematic flowchart of a manufacturing method of a battery cell provided by some embodiments of the present application.

As shown in <FIG>, the manufacturing method of the battery cell according to the embodiments of the present application includes:.

It should be noted that, for the related structure of the battery cell manufactured by the above manufacturing method of the battery cell, reference can be made to the battery cell provided by the above embodiments.

When the battery cell is assembled based on the above manufacturing method of the battery cell, it is not necessary to execute the above steps in sequence, that is, the steps may be executed in the order mentioned in the embodiment, or may be executed in an order different from the one mentioned in the embodiment, or several steps are executed simultaneously. For example, steps S100, S200, S300, and S400 are executed in no particular order, and may also be executed simultaneously.

<FIG> is a schematic block diagram of a manufacturing system of a battery cell provided by some embodiments of the present application.

As shown in <FIG>, a manufacturing system <NUM> of a battery cell of the embodiments of the present application includes: an electrode assembly providing apparatus <NUM> for providing an electrode assembly; a housing providing apparatus <NUM> for providing a housing, where the housing is provided with an accommodating space for accommodating the electrode assembly; and the housing includes a first side plate located on a side in a first direction; a pressure relief mechanism providing apparatus <NUM> for providing a pressure relief mechanism, where the pressure relief mechanism is disposed on the first side plate; a cover assembly providing apparatus <NUM> for providing a cover assembly for sealing the housing; and an assembly apparatus <NUM> for assembling the electrode assembly, the housing, the pressure relief mechanism and the cover assembly to form the battery cell, where an inner surface of the first side plate of the housing is provided with a first flow channel extending along the inner surface, and the first flow channel is configured to guide a gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated when a pressure reaches a threshold, and relieves the pressure; and the first flow channel comprises a first intermediate flow channel and a first edge flow channel, the first edge flow channel extends along a circumferential edge of the inner surface of the first side plate and communicates with the accommodating space, and the first edge flow channel and the pressure relief mechanism are in communication through the first intermediate flow channel.

For the related structure of the battery cell manufactured by the above manufacturing system, reference may be made to the battery cell provided by the above embodiments.

Claim 1:
A battery cell, comprising:
an electrode assembly (<NUM>);
a housing (<NUM>) provided with an accommodating space for accommodating the electrode assembly (<NUM>), wherein the housing (<NUM>) comprises a first side plate (<NUM>) located on a side in a first direction;
a first pressure relief hole (<NUM>) penetrating the first side plate (<NUM>) in a thickness direction;
a pressure relief mechanism (<NUM>) disposed on the first side plate (<NUM>) to cover the first pressure relief hole (<NUM>); and
a cover assembly (<NUM>) for sealing the housing (<NUM>),
characterised in that
an inner surface of the first side plate (<NUM>) of the housing (<NUM>) is provided with a first flow channel extending along the inner surface, and the first flow channel is configured to guide a gas in the accommodating space to the pressure relief mechanism (<NUM>) so that the pressure relief mechanism (<NUM>) is actuated when a pressure reaches a threshold, and relieves the pressure; and
the first flow channel comprises a first intermediate flow channel (<NUM>) and a first edge flow channel (<NUM>), the first edge flow channel (<NUM>) extends along a circumferential edge of the inner surface of the first side plate (<NUM>) and communicates with the accommodating space, and the first edge flow channel (<NUM>) and the pressure relief mechanism (<NUM>) are in communication through the first intermediate flow channel (<NUM>).