Patent Description:
In the trend of energy conservation and emission reduction, batteries are widely used in a field of new energy, such as electric vehicles, new energy vehicles, etc., and the electric vehicles have become an important part of a sustainable development of an automotive industry.

In the development of battery technology, safety performance and service life of a battery are elements that cannot be ignored. During use of the battery, leakage often has a large adverse effect on the safety performance and service life of the battery.

<CIT> discloses a cylindrical battery including a gap formed between a peripheral side surface of a dish-shaped portion in an anode terminal plate and a curved end portion of a cathode can, and a washer having a washer boss portion and an annular flange portion provided around an upper end surface of the washer boss portion, the washer being mounted to an opening portion of a cathode can such that the washer boss portion is fitted into the gap, a vent structure configured to release gas released to the gap from a first vent hole in the anode terminal plate is provided in a range surrounded by a ridge line connecting a highest part of the curved end portion in the washer and the peripheral side surface of the anode terminal plate.

<CIT> discloses a rechargeable battery including an electrode assembly capable of being charged and discharged; a case accommodating the electrode assembly; a cap assembly, the cap assembly including a cap plate coupled to an opening of the case, and a vent member in the cap plate, the vent member being configured to open at a predetermined internal pressure, a terminal exposed to an outer side of the cap plate; a lower insulating member, the lower insulating member insulating the terminal and the cap plate at a lower side of the cap plate; and a channel member between the electrode assembly and the cap plate and forming a space, the channel member being fixed to the lower insulating member.

<CIT> discloses a rechargeable battery includes an electrode assembly having a positive electrode, a negative electrode, and a separator located between the positive electrode and the negative electrode; a case housing the electrode assembly, the case having an opening; a cap assembly including a cap plate coupled to the opening of the case and a vent member on the cap plate adapted to discharge a gas from the case; and a separation member located between the electrode assembly and the cap plate to prevent the electrode assembly from significantly moving toward the cap plate.

The present application aims to provide a battery cell, a battery, a power consumption apparatus, a method and an apparatus for producing a battery cell, such that a problem of battery leakage can be alleviated to improve safety performance and service life of the battery.

In a first aspect, embodiments of the present application provide a battery cell, including:.

In the technical solution of the embodiments of the present application, the battery cell is provided with the pressure relief mechanism, and when the internal pressure or temperature of the battery cell reaches a predetermined threshold, the pressure relief mechanism is actuated to relieve the internal pressure or temperature to ensure safety of the battery cell; when the battery cell is impacted, or drops from a high place, etc., causing an electrolytic solution inside the battery cell to slosh, and the first insulating member is used to completely cover the pressure relief mechanism to prevent the pressure relief mechanism from opening or cracking due to an impact of electrolytic solution sloshing, resulting in leakage of the electrolytic solution, thereby increasing life of the battery cell.

When the internal pressure or temperature of the battery cell reaches the threshold, the pressure relief mechanism is actuated under the pressure, and a gas inside the battery cell reaches the first gap through the flow path to be relieved from the pressure relief mechanism, so that functions of the pressure relief mechanism can be ensured while reducing the leakage of the battery cell, thereby improving the safety of the battery cell.

The second opening on the first insulating member enables emissions inside the battery cell to be smoothly relieved from the pressure relief mechanism. Since the second opening on the first insulating member is staggered with the pressure relief mechanism, when the electrolytic solution sloshes in the housing due to impact or drop of the battery, it can effectively prevent the electrolytic solution from impacting the pressure relief mechanism, and even if the electrolytic solution flows to the first gap from the second opening, impact force acts mainly on the end cover, and the pressure relief mechanism may not be directly impacted.

In an embodiment of the present application, optionally, the second opening is located at an outer periphery of the first insulating member.

When the second opening is located at the outer periphery of the first insulating member, the electrode assembly is not easy to block the second opening compared with a position arranged in the middle of the first insulating member, so as to ensure the emissions can be smoothly relieved, thereby improving the safety of the battery.

In an embodiment of the present application, optionally, the first insulating member includes a base wall and a side wall, the base wall is arranged opposite to the end cover, the first gap is formed between the base wall and the end cover, the side wall is arranged around outer periphery of the base wall, and the second opening is arranged on the side wall.

The side wall is arranged around the outer periphery of the base wall, which can improve a structural strength of the base wall and ensure the base wall to be not easily flexed and deformed. At the same time, since the second opening is arranged on the side wall, it can further prevent the second opening from being blocked and ensure the second opening can communicate the inner portion of the battery cell with the first gap to smoothly relieve the emissions, thereby ensuring the safety of the battery cell. In an embodiment of the present application, optionally, the side wall has a first end close to the end cover and a second end away from the end cover, and the second opening is a groove recessed by the side wall from the first end towards the second end.

In an embodiment of the present application, optionally, the first end protrudes from the base wall, and a depth of the groove is smaller than a height of the first end protruding from the base wall.

Since the depth of the groove is less than the height of the first end protruding from the base wall, the side wall can still maintain a state surrounding the base wall when possessing the second opening, thereby ensuring the structural strength and ensuring the base wall not easy to be deformed.

In an embodiment of the present application, optionally, the first end abuts against the end cover, and the second end abuts against the electrode assembly.

The end cover tightly presses the electrode assembly through the first insulating member, so that the position of the electrode assembly is restrained in an axial direction, thereby preventing the electrode assembly from sloshing in the axial direction. In an embodiment of the present application, optionally, the battery cell further includes:.

The first connection section, the second connection section and the third connection section of the current collecting plate are stacked in sequence, where the second connection section and the third connection section form a stepped structure, so as to reverse more space at a position corresponding to the pressure relief mechanism; and the base wall forms the step, which can not only tightly press the current collecting plate, but also enlarge the position of the first gap corresponded to the second gap. By arranging as above, the first gap can be arranged as large as possible without increasing an overall thickness of the end cover assembly, so that an exhaust rate can be as high as possible when the pressure is required to be relieved, thereby improving the safety of the battery cell.

Moreover, since the second opening is located at the second part, the first gap is relatively enlarged here, which enables the emissions in the flow path to swiftly enter the first gap, further playing the effect of rapidly relieving and improving the safety of the battery cell.

In the above technical solution, a distance between the second opening and the pressure relief mechanism is relatively short, the emissions can reach the pressure relief mechanism and be discharged relatively swiftly, thereby increasing a response speed of the pressure relief mechanism.

In an embodiment of the present application, optionally, a first positioning portion is arranged on the end cover, a second positioning portion is arranged on the base wall, and the first positioning portion is matched with the second positioning portion to implement a peripheral positioning of the end cover and the first insulating member.

The end cover is matched with the first insulating member through the first positioning portion and the second positioning portion, which can not only implement a quick and correct assembly of the end cover and the first insulating member, but also define a relative position of the end cover and the first insulating member in a peripheral direction, so as to ensure that the second opening and the pressure relief mechanism maintain a relative positional relationship, thereby ensuring the safety and structural stability of the battery cell.

In an embodiment of the present application, optionally, an area of the second opening is greater than or equal to one half of an area of a projection of the pressure relief mechanism on the end cover along a thickness direction of the end cover.

It is arranged that the area of the second opening is greater than or equal to one half of the area of the pressure relief mechanism, which can avoid a problem that the area of the second opening is too small to ensure a normal actuation of the pressure relief mechanism, and ensure that at least a valve opening pressure value is reached at the first gap when the internal pressure of the battery cell reaches a limit pressure value, thereby ensuring the safety of the battery cell.

In an embodiment of the present application, optionally, the flow path comprises a second gap formed between an outer peripheral surface of the first insulating member and an inner wall of the housing, and the second gap is configured that a projection of the second gap on the end cover along the thickness direction of the end cover is staggered with the pressure relief mechanism.

The second gap is used to directly communicate with the first gap, or the second gap communicates with the second gap through the second opening, so as to meet requirements for relieving the pressure through the pressure relief mechanism, and to prevent the electrolytic solution from impacting the pressure relief mechanism as well by staggering the second gap with the pressure relief mechanism.

In an embodiment of the present application, optionally, a smallest ventilation area of the second gap is greater than or equal to one half of the area of a projection of the pressure relief mechanism on the end cover along a thickness direction of the end cover.

When the smallest ventilation area of the second gap is greater than or equal to one half of the pressure relief mechanism, it can effectively avoid a problem that the ventilation area of the second gap is too small to actuate that the pressure relief mechanism normally, and can ensure that the valve opening pressure value is reached at the first gap at least when the internal pressure of the battery cell reaches the limit pressure value, thereby ensuring the safety of the battery cell.

In an embodiment of the present application, optionally, at least part of the outer peripheral surface of the first insulating member is an inclined face, so that a width of the second gap gradually increases along a direction away from the end cover.

Since the first insulating member is configured that at least it is the inclined face at the second gap, it can not only facilitate the gas to converge into the second gap and enter the first gap to be relieved, but also avoid second gap blockage due to an interference between the first insulating member and the inner wall of the housing caused by manufacturing tolerances. In addition, a condition of an interference between the end cover assembly and the inner wall of the housing can be reduced when the end cover assembly is assembled to the second opening of the housing.

In a second aspect, the embodiments of the present application provides a battery, including the aforementioned battery cell.

For the battery provided by the embodiment, each battery cell inside the battery respectively has a pressure relief mechanism to ensure the safety, and the pressure relief mechanism is not easily damaged when each battery cell is impacted or drops. Overall durability and safety performance of the battery are good.

In a third aspect, the embodiments of the present application provide a power consumption apparatus, including the aforementioned battery, and the battery is configured to provide electrical energy.

The power consumption apparatus provided in the embodiment is installed with a battery with good anti-fall performance, durability performance and safety performance, and power supply reliability of the battery is high. The power consumption apparatus has effects of stable operation, high safety and good durability.

In a fourth aspect, the embodiments of the present application provides a method for producing a battery cell, including:.

In a fifth aspect, the embodiments of the present application provides an apparatus for producing a battery cell, including:.

The above description is only an overview of the technical solution of the embodiments of the present application. In order to better understand the technical means of the embodiments of the present application, it can be implemented in accordance with the content of the description, and in order to make the above and other objectives, features and advantages of the embodiments of the present application more obvious and understandable, the specific embodiments of the present application is given as follows.

In order to illustrate the technical solution in the embodiments of the present application more clearly, brief description will be made below to the drawings required in the embodiments of the present application. Apparently, the drawings described below are some embodiments of the present application only, and other drawings could be obtained based on these drawings by those ordinary skilled in this field without creative efforts.

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

To make the objectives, technical solutions and advantages of the embodiments of the present application become clearer, the following clearly describes the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Apparently, the described embodiments are part 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 to which the present application belongs. The 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. The terms "including" and "having" and any variations thereof in the specification and the claims of the present application as well as the foregoing description of the drawings are intended to cover non-exclusive inclusions. The terms "first", "second" and the like in the specification and the claims of the present application as well as the foregoing description of the drawings are used to distinguish different objects, rather than to describe a specific order or primary-secondary relationship.

The phrase "embodiments" referred in the present application means that the descriptions of specific features, structures, and characteristics in combination with the embodiments are 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. Those skilled in the art understand, in explicit or implicit manners, that an embodiment described in the present application may be combined with other embodiments.

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

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

In the embodiments of the present application, same components are denoted by same reference numerals, and detailed description of the same component 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 of 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, "a plurality of" means two or more (including two), similarly, "a plurality of groups" means two or more groups (including two groups), and "a plurality of sheets" means two or more sheets (including two sheets).

In the present application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., which are not limited by the embodiments of the present application. The battery cell may be cylindrical, flat, cuboid or other shapes, which are not limited by the embodiments of the present application as well. 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 soft package battery cells, which are not limited by the embodiments of the present application as well.

The battery mentioned in the 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 body for enclosing one or more battery cells. The box body may prevent liquid or other foreign matters from affecting the charging or discharging of the battery cell.

The battery cells includes an electrode assembly and an electrolytic solution, and the electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The operation of the battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on a surface of the positive electrode current collector, a current collector not coated with the positive electrode active material layer protrudes from a current collector coated with the positive electrode active material layer, and the current collector not coated with the positive electrode active material layer is used as a positive electrode tab. As an example, in a lithium-ion battery, a material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobalt oxides, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on a surface of the negative electrode current collector, a current collector not coated with the negative electrode active material layer protrudes from a current collector coated with the negative electrode active material layer, and the current collector not coated with the negative electrode active material layer is used as a negative electrode tab. A material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that no fusing occurs when a large current passes, there are a plurality of positive electrode tabs which are stacked together, and there are a plurality of negative electrode tabs which are stacked together. A material of the separator may be PP, PE, or the like. In addition, the electrode assembly may be a winding structure or a laminated structure, and the embodiments of the present application are not limited thereto. With the development of battery technology, it is necessary to consider many design factors at the same time, such as energy density, cycle life, discharge capacity, charge-discharge rate and other performance parameters. In addition, safety of batteries should also be considered.

With regard to the battery cell, main safety hazards come from charging and discharging processes, and a suitable environmental temperature design is also required. In order to effectively avoid unnecessary losses, at least triple protecting measures are generally adopted for the battery cell. Specifically, the protecting measures include at least a switching element, a properly selected separator material and a pressure relief mechanism. The switching element refers to an element that can stop the charging or discharging of the battery when the temperature or resistance in a battery cell reaches a certain threshold. The separator is used to isolate the positive electrode sheet from the negative electrode sheet and can automatically dissolve micron-sized (or even nanoscale) micro-pores attached to the separator when the temperature rises to a certain value, thereby preventing metal ions from passing through the separator , terminating an internal reaction of the battery cell.

The pressure relief mechanism refers to an element or a component that is actuated to relieve an internal pressure or temperature when the internal pressure or temperature of the battery cell reaches a predetermined threshold. The threshold design is different according to different design requirements. The threshold may depend on materials of one or more of the positive electrode sheet, the negative electrode sheet, the electrolytic solution and the separator in the battery cell.

The "actuate" mentioned in the present application refers that the pressure relief mechanism produces an action or is activated to a certain state, so that the internal pressure and temperature of the battery cell can be relieved. The action produced by the pressure relief mechanism may include but be not limited to: at least a portion of the pressure relief mechanism being 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 outwards from an actuated position as emissions. In this way, the pressure in the battery cell can be relieved at a controllable pressure or temperature, thereby avoiding potentially more serious accidents.

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

The pressure relief mechanism on the battery cell has an important effect on the safety of the battery. For example, when short circuit, overcharge and other phenomena occurs, it may lead to thermal runaway inside the battery cell, resulting in a sudden increase of pressure or temperature. In this case, the internal pressure and temperature may be released outwards through the actuation of the pressure relief mechanism, to prevent the battery cell from exploding and catching fire.

The pressure relief mechanism may take the form of an anti-explosion valve, an air valve, a pressure relief valve, a safety valve or the like, and may specifically adopt a pressure-sensitive or temperature-sensitive element or structure. That is, when the internal pressure or temperature of the battery cell reaches the predetermined threshold, the pressure relief mechanism performs an action or a weakened structure provided in the pressure relief mechanism is damaged, so as to form a through opening or a channel for relieving the internal pressure or temperature.

The battery cell sometimes leaks during use. When the battery cell leaks, it means that the battery cell cannot work normally, thereby affecting life of the battery cell. The inventor researched and discovered that a leakage often occurs at the pressure relief mechanism, and even if there is no abnormal gas production or high temperature problem in the battery cell, the pressure relief mechanism may also leak. After leaking, the inventor exchanged a pressure relief mechanism with better quality, but the problem of the leakage cannot be solved. Therefore, the inventor further researched and discovered that when the battery cell is impacted or drops, the electrolytic solution may slosh inside the battery cell and then impact the pressure relief mechanism, so that the pressure relief mechanism is opened, damaged or cracked, resulting in the leakage of the electrolytic solution. Even when the electrolytic solution impacts the pressure relief mechanism, the pressure relief mechanism does not produce obvious damages, but only produces hard-to-observe cracks, which may also reduce the structural strength of the pressure relief mechanism. In the subsequent use process, an abnormal situation may occur in which the internal pressure of the battery cell is within a normal range but the pressure relief mechanism is actuated, thereby reducing the safety and service life of the battery cell.

In view of this, in order to enhance the safety and service life of the battery cell, the embodiments of the present application provide a technical solution, that is, a protective structure for shielding the pressure relief mechanism is arranged at a position corresponding to the pressure relief mechanism of the battery cell, and when the electrolytic solution inside the battery cell sloshes, the protective structure blocks impulse towards the pressure relief mechanism, so as to avoid the damages to the pressure relief mechanism, thereby further solving a problem of the reduced safety and service life of the battery cell caused by the leakage.

The technical solution described in the embodiments of the present application are all applicable to various devices using batteries, such as mobile phones, portable apparatuses, notebook computers, electromobiles, electric toys, electric tools, electric vehicles, ships, spacecrafts and so on. For example, the spacecrafts include airplanes, rockets, space shuttles, spaceships and so on.

It should be understood that the technical solution described in the embodiments of the present application are not only applicable to the devices described above, but also applicable to all devices using batteries. However, for ease of description, the following embodiments are all described by an example of an electric vehicle.

For example, as shown in <FIG> is a vehicle <NUM> according to an embodiment of the present application. The vehicle <NUM> may be a fuel-powered vehicle, a gas-powered vehicle or an alternative fuel vehicle, and the new energy vehicle may be a battery electric vehicle, a hybrid vehicle, an extended-range vehicle, or the like. A motor <NUM>, a controller <NUM> and a battery <NUM> may be arranged inside the vehicle <NUM>, and the controller <NUM> is used to control the battery <NUM> to supply power to the motor <NUM>. For example, the battery <NUM> may be disposed at the bottom, head or tail of the vehicle <NUM>. The battery <NUM> may be used for supplying power of the vehicle <NUM>. For example, the battery <NUM> may serve as an operation power source of the vehicle <NUM> for a circuit system of the vehicle <NUM>, for example, for a working power demand of the vehicle <NUM> during startup, navigation and run. In another embodiment of the present application, the battery <NUM> may serve not only as an operating 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>.

In order to meet different power demands, the battery <NUM> may include a plurality of battery cells, where the plurality of battery cells may be in series connection, parallel connection or series-parallel connection. The series-parallel connection refers to a combination of series connection and parallel connection. The battery <NUM> may also be called a battery pack. Optionally, please be shown in a combination with <FIG> and <FIG>, a plurality of battery cells may be first connected in series, in parallel or in series-parallel to form a battery module <NUM>, and then a plurality of battery modules <NUM> are connected in series, in parallel or in series-parallel to form the battery <NUM>. That is, the plurality of battery cells may directly form the battery <NUM>, or may first form the battery module <NUM>, and then the battery modules <NUM> form the battery <NUM>.

The battery <NUM> may include a plurality of battery cells. The battery <NUM> may further include a box body <NUM> (or a covering). The inner portion of the box body <NUM> is a hollow structure, and the plurality of battery cells are accommodated in the box body <NUM>. The box body <NUM> may include two parts for accommodation (refer to <FIG>), which are referred herein as a cover body <NUM> and a lower box body <NUM>, respectively, and the cover body <NUM> and the lower box body <NUM> are buckled together. The shapes of the cover body <NUM> and the lower box body <NUM> may be determined according to the shape of the combined plurality of battery cells, and both the cover body <NUM> and the lower box body <NUM> can have an opening. For example, the cover body <NUM> and the lower box body <NUM> each can be a hollow cuboid and only one surface of each is an opening surface, and the opening of the cover body <NUM> is arranged opposite to the opening of the lower box body <NUM>, and the cover body <NUM> and the lower box body <NUM> are buckled to each other to form the box body <NUM> with a closed chamber. One of the cover body <NUM> and the lower box body <NUM> can also be a cuboid with an opening, and the other is a cover structure to enclose the opening of the cuboid. The plurality of battery cells are combined in parallel connection or series connection or series-parallel connection and are then placed in the box body <NUM> formed by buckling the cover body <NUM> to the lower box body <NUM>.

Optionally, the battery <NUM> may also include other structures. For example, the battery <NUM> may also include a busbar. The busbar is used to implement an electrical connection between the plurality of battery cells <NUM>, such as parallel connection, series connection or series-parallel connection. Specifically, the busbar can realized the electrical connection between the battery cells <NUM> by connecting electrode terminals of the battery cells <NUM>. Furthermore, the busbar can be fixed to the electrode terminals of the battery cells <NUM> by means of welding. Electrical energy of the plurality of battery cells <NUM> can be further led out through an electrically conductive mechanism passing through the box body <NUM>. Optionally, the electrically conductive mechanism may also belong to the busbar.

Any battery cell <NUM> is described in detail in the following. <FIG> and <FIG> show a battery cell <NUM> according to an embodiment of the present application, and the battery cell <NUM> includes a housing <NUM>, an end cover assembly <NUM> and one or more electrode assemblies <NUM>. The housing <NUM> is shaped according to the shape of one or more electrode assemblies <NUM> after combination. For example, the housing <NUM> may be a hollow cuboid or cube or cylinder, and one surface of the housing <NUM> has an opening so that one or more electrode assemblies <NUM> can be placed in the housing <NUM>. For convenience of description, the opening is hereinafter referred to as a first opening <NUM>. For example, when the housing <NUM> is a hollow cuboid or cube, one plane of the housing <NUM> is a plane with the first opening <NUM>, and the plane is configured to have no wall body, so that the inside and outside of the housing <NUM> are in communication with each other. When the housing <NUM> is a hollow cylinder, an end face of the housing <NUM> is a surface with the first opening <NUM>, that is, the end face is configured to have no wall body, so that the inside and outside of the housing <NUM> are in communication with each other. The end cover assembly <NUM> covers the first opening <NUM> and is connected to the housing <NUM> to form an enclosed chamber for placing the electrode assembly <NUM>, and the enclosed chamber is filled with electrolyte, such as the electrolytic solution.

The end cover assembly <NUM> includes an end cover <NUM> and a pressure relief mechanism <NUM>, the end cover <NUM> is used to cover the first opening <NUM> of the housing <NUM> and is connected to the housing <NUM>, the pressure relief mechanism <NUM> is arranged on the end cover <NUM>, and when an internal pressure or temperature of the battery cell <NUM> reaches a predetermined threshold, the pressure relief mechanism <NUM> performs an action or a weak structure provided in the pressure relief mechanism <NUM> is damaged, thereby relieving the internal pressure of the enclosed chamber.

The battery cell <NUM> further includes one or more electrode terminals <NUM>, and the electrode terminal <NUM> can be arranged on the end cover <NUM>. The end cover <NUM> is generally in the shape of a flat plate, the electrode terminal <NUM> is fixed on a flat plate face of the end cover <NUM>, and the electrode terminal <NUM> is connected with a connecting member, or may also called an current collecting plate <NUM>, which is located between the end cover <NUM> and the electrode assembly <NUM>, and is used to electrically connect the electrode assembly <NUM> and the electrode terminal <NUM>.

Each electrode assembly <NUM> has a first electrode tab and a second electrode tab. The first electrode tab and the second electrode tab have opposite polarities. For example, when the first electrode tab is a positive electrode tab, the second electrode tab is a negative electrode tab. The first electrode tab of one or more electrode assemblies is connected to one electrode terminal through one current collecting plate, for example, a positive electrode terminal; and the second electrode tab of one or more electrode assemblies is connected to another electrode terminal through another current collecting plate, for example, a negative electrode terminal. That is, the positive electrode terminal is connected to the positive electrode tab through one current collecting plate, and the negative electrode terminal is connected to the negative electrode tab through another current collecting plate.

In the battery cell <NUM>, one or more electrode assemblies <NUM> can be arranged according to actual use requirements. As shown in <FIG>, one independent electrode assembly <NUM> is arranged in the battery cell <NUM>.

The first electrode tab <NUM> and the second electrode tab <NUM> of the electrode assembly <NUM> can be arranged at the same end, or as shown in <FIG>, the first electrode tab <NUM> and the second electrode tab <NUM> of the electrode assembly <NUM> are arranged at two ends, respectively. That is, one end of the electrode assembly <NUM> is provided with the first electrode tab <NUM> and the other end is provided with the second electrode tab <NUM>. Correspondingly, two ends of the housing <NUM> of the battery cell <NUM> has the first opening <NUM>, respectively, and each first opening <NUM> is provided with the end cover assembly <NUM>, respectively, and the electrode terminal <NUM> provided in each end cover assembly <NUM> respectively is connected to a tab through the current collecting plate <NUM>. The structure of each end cover assembly <NUM> and its connection structure with the housing <NUM> can be the same, and the following takes one end cover assembly <NUM> as an example for description.

As shown in <FIG>, the end cover assembly <NUM> further includes a first insulating member <NUM> and a second insulating member <NUM>. The first insulating member <NUM> is located at a side of the end cover <NUM> close to the electrode assembly <NUM>, that is, the first insulating member <NUM> is located between the end cover <NUM> and the electrode assembly <NUM> to isolate the electrode assembly <NUM> and the end cover <NUM>. The second insulating member <NUM> is located between the end cover <NUM> and the electrode terminal <NUM> to isolate the electrode terminal <NUM> and the end cover <NUM>.

The first insulating member <NUM> is configured that a projection of the first insulating member <NUM> on the end cover <NUM> along a thickness direction D of the end cove covers the pressure relief mechanism <NUM>. When the battery cell <NUM> is impacted or drops, resulting in the internal electrolytic solution sloshing in the housing <NUM> and impacting towards the end cover <NUM>, the first insulating member <NUM> blocks the electrolytic solution and bears the impact instead of the pressure relief mechanism <NUM>, thereby protecting the pressure relief mechanism <NUM> to prevent the pressure relief mechanism <NUM> from being damaged.

In the present application, the first insulating member <NUM> shielding the pressure relief mechanism <NUM> refers that the first insulating member <NUM> completely shields the pressure relief mechanism <NUM> along the thickness direction D of the end cover, or completely shields the weak structure on the pressure relief mechanism <NUM>, so as to prevent the weak structure of the pressure relief mechanism <NUM> from being damaged due to a direct impact of the electrolytic solution.

In order to take into account the safety of the battery cell <NUM>, in the thickness direction D of the end cover, there is also a first gap A formed between the first insulating member <NUM> and the pressure relief mechanism <NUM>. At the same time, a flow path is formed in the battery cell <NUM>, which is used to communicate the inside of the battery cell <NUM> with the first gap A. When the pressure relief mechanism <NUM> is actuated, the emissions such as gas inside the battery cell <NUM> can reach the first gap A through the flow path, and can be relieved from the pressure relief mechanism <NUM> to the outside of the battery cell <NUM>.

The inside of the battery cell <NUM> refers to a space formed between the end cover assembly <NUM> and an inner wall of the housing <NUM> when the end cover assembly <NUM> covers the first opening <NUM> of the housing <NUM>. In the present application, there is a space accommodating the electrode assembly <NUM> enclosed by the first insulating member <NUM> and the housing <NUM>.

The first insulating member <NUM> may be configured to be integrally spaced from the end cover <NUM>, thereby forming the first gap A.

Or, a part of the first insulating member <NUM> fits or abuts against the end cover <NUM>, and another part is separated from the end cover <NUM> to form the first gap A. In some embodiments, the first insulating member <NUM> forms a recess on a side facing the end cover <NUM>, and a projection of the recess on the end cover <NUM> corresponds to the pressure relief mechanism <NUM>, so that the first gap A is formed between the first insulating member <NUM> and the pressure relief mechanism <NUM>.

In some embodiments, the end cover <NUM> may extend beyond the pressure relief mechanism <NUM> on a surface facing the first insulating member <NUM>, so that a distance between the pressure relief mechanism <NUM> and the first insulating member <NUM> is greater than a distance between the end cover <NUM> and the first insulating member <NUM>, and thus the first gap A is formed between the first insulating member <NUM> and the pressure relief mechanism <NUM>.

In some embodiments, the current collecting plate <NUM> forms a avoiding space at a position corresponding to the pressure relief mechanism <NUM>, so that the first insulating member <NUM> can be further away from the pressure relief mechanism <NUM>, so as to increase the first gap A to improve a relieving effect without changing an overall occupied space of a cover plate assembly and the current collecting plate <NUM>.

Please refer to <FIG> again, the current collecting plate <NUM> includes a first connection section <NUM>, a second connection section <NUM> and a third connection section <NUM>, where the first connection section <NUM> connects the electrode assembly <NUM>, the third connection section <NUM> connects the electrode terminal <NUM>, and the second connection section connects the first connection section <NUM> and the third connection section <NUM>.

Creases are formed between the first connection section <NUM> and the second connection section <NUM>, and between the second connection section <NUM> and the third connection section <NUM>, respectively, so that the first connection section <NUM>, the second connection section <NUM> and the third connection section <NUM> are stacked in sequence along the thickness direction D of the end cover. The first connection section <NUM>, the second connection section <NUM> and the third connection section <NUM> may have different lengths. Here, the length of the first connection section <NUM> refers to a distance from one end of the current collecting plate <NUM> to a crease between the first connection section <NUM> and the second connection section <NUM>, the length of the second connection section <NUM> refers to a distance between the crease between the first connection section <NUM> and the second connection section <NUM> and a crease between the second connection section <NUM> and the third connection section <NUM>, and the length of the third connection section <NUM> refers to a distance from the crease between the second connection section <NUM> and the third connection section <NUM> to the other end of the current collecting plate <NUM>. Among them, the length of the third connection section <NUM> is shorter than that of the second connection section <NUM>, so that the third connection section <NUM> is stacked on the second connection section <NUM> to form a stepped structure.

As shown in a combination with <FIG> and <FIG>, the first insulating member <NUM> includes a base wall <NUM>, composed of a first base 331a and a second base 331b, the base wall is arranged opposite to the end cover <NUM>, a step is formed between the first base 331a and the second base 331b, and here, the step mentioned refers that the first base 331a and the second base 331b turns at a position of connection to form two planes with a height difference. The first base 331a is arranged between the end cover <NUM> and the third connection section <NUM>, a side of the second base 331b tightly presses a part of the second connection section <NUM> that is not covered by the third connection section <NUM>, and the other side of the second base 331b is spaced from the end cover <NUM> to form the first gap A.

The first insulating member <NUM> in the embodiment not only forms the first gap A between the second base 331b and the pressure relief mechanism <NUM> to ensure the safety of the battery cell <NUM>, but also can transmit pressure through the first base 331a to tightly press the current collecting plate <NUM> to stabilize the assembly.

In some embodiments, the first insulating member <NUM> may not abut against the current collecting plate <NUM>, the current collecting plate <NUM> may still form the stepped structure by making the third connection section <NUM> shorter than the second connection section <NUM>, so that the avoiding space is formed in an area on the current collecting plate <NUM> corresponding to the pressure relief mechanism <NUM> to provide the space for forming the first gap A.

In some embodiments, the flow path may include a second opening B formed on the first insulating member <NUM> (refer to <FIG>). A projection of the second opening B on the end cover <NUM> is staggered with the pressure relief mechanism <NUM> along the thickness direction D of the end cover <NUM>, so that the first insulating member <NUM> prevent the electrolytic solution from directly impacting the pressure relief mechanism <NUM> when the electrolytic solution sloshes. When the internal pressure or temperature of the battery cell <NUM> reaches the predetermined threshold, the emissions enter the first gap A through the second opening B to be discharged through the pressure relief mechanism <NUM>.

The second opening B on the first insulating member <NUM> may be formed on the base wall <NUM> of the first insulating member <NUM>, and its projection on the end cover <NUM> is staggered with the pressure relief mechanism <NUM>.

For example, as shown in <FIG>, at a position close to the middle of the base wall <NUM> (that is, a position away from outer periphery of the base wall <NUM>), a hole is formed on the second base 331b penetrating from one side to the other, a penetrating direction may be along the thickness direction D of the end cover, or may also be inclined relative to the thickness direction D of the end cover and an inclination angle is less than <NUM>°, and the penetrated hole serves as the second opening B for relieving.

The second opening B may also be formed at the connection position of the first base 331a and the second base 331b, which is a part of the base wall <NUM> for connecting the first base 331a and the second base 331b with the height difference, and the part is at a certain angle with the first base 331a and the second base 331b. As shown in <FIG>, a hole penetrating from one side to the other is formed on the part, and a penetrating direction is perpendicular to the thickness direction D of the end cover, and the penetrated hole communicates the inside of the battery cell with the first gap A, which serves as the second opening for relieving.

When the second opening B is close to a middle position of the base wall <NUM>, or when the second opening B is on the part of the connection position of the first base 331a and the second base 331b, the second opening B is relatively close to a tab of the electrode assembly <NUM>, and the tab may be deformed to block the second opening B. In some embodiments, the second opening B may also be formed on the outer periphery of the second base 331b, so that the second opening B is relatively far away from the tab. As shown in <FIG>, the base wall <NUM> is recessed from the outer periphery along a radial direction to form a gap, which serves as the second opening B for relieving.

In an embodiment provided by the present application, the first insulating member <NUM> further includes a side wall <NUM> arranged around the outer periphery of the base wall <NUM>. <FIG> shows a top view diagram of the first insulating member <NUM>, and <FIG> shows a main view diagram of the first insulating member <NUM>. The side wall <NUM> increases the structural strength of the base wall <NUM>, so that the base wall <NUM> is not easily flexed and deformed, so as to transmit the pressure in a better way, so that the end cover <NUM> tightly presses the current collecting plate <NUM> on the electrode assembly <NUM> through the first insulating member <NUM>, which can effectively prevent the current collecting plate <NUM> and the electrode assembly <NUM> from dislocation under impact force or other forces, so as to avoid a loose connection between the tab, the current collecting plate <NUM> and the electrode terminal <NUM>.

In some embodiments, the second opening B on the first insulating member <NUM> may also be formed on the side wall <NUM>, at this time, the flow path further includes a second gap C formed between an outer peripheral surface of the first insulating member <NUM> and the inner wall of the housing <NUM> (refer to <FIG>), and along the thickness direction D of the end cover, a projection of the second gap C on the end cover <NUM> along the thickness direction D of the end cover is staggered with the pressure relief mechanism <NUM>. The second opening B on the side wall <NUM> communicates the first gap A with the second gap C, and the emissions enter the first gap A through the second opening B after entering the second gap C to be relieved from the pressure relief mechanism <NUM>. When the second opening B is located on the side wall <NUM>, it is far away from the tab, and thus has an effect of not being easily blocked by the tab.

For convenience of description, the side wall <NUM> can be regarded as including a first part 332a and a second part 332b, where the first part 332a is a part connecting the first base 331a, and the second 332b is a part connecting the second base 331b; for further convenience of description, an end of the side wall <NUM> close to the end cover <NUM> is a first end <NUM>, and an end of the side wall <NUM> away from the end cover <NUM> is a second end <NUM>.

In some embodiments, the first end <NUM> of the side wall <NUM> is not in contact with the end cover <NUM> to form the second opening B communicating the second gap C with the first gap A. For example, the first end <NUM> of the side wall <NUM> is not in contact with the end cover <NUM> at all, so that an annular-shaped second opening B is defined between an end face of the first end <NUM> of the side wall <NUM> and the end cover <NUM>. At this time, the first end <NUM> may not protrude from the base wall <NUM>, or the first end <NUM> may protrude from the base wall <NUM> but not in contact with the end cover <NUM>.

In other embodiments, a part of the first end <NUM> of the side wall <NUM> is not in contact with the end cover <NUM>, and the other part is in contact with the end cover <NUM>, so that the second opening B is defined between an end face that the first end <NUM> is not in contact with the end cover <NUM> and the end cover <NUM>. And the second opening B is at least partially located at the second part 332b of the side wall <NUM>, so that the second opening B effectively communicates the first gap A with the second gap C.

As shown in <FIG>, the first end <NUM> of the side wall <NUM> protrudes from the base wall <NUM> and abuts against the end cover <NUM>, the first end <NUM> of the side wall <NUM> is recessed towards the second end <NUM> to form a groove, and the groove serves as the second opening B connecting the first gap A and the second gap C.

When the first end <NUM> of the side wall <NUM> is only partially not in contact with the end cover <NUM>, the base wall <NUM> is not easy to be deformed due to an action of the side wall <NUM>, and the first end <NUM> of the side wall <NUM> abuts against the end cover <NUM> to transmit the pressure of the end cover, so that the base wall <NUM> can tightly press the adaptor in a better way while the groove on the side wall <NUM> serves as the second opening B to meet discharge requirements.

In order to take into account a relieving function and the structural strength of the first insulating member <NUM>, the second opening B is configured as a groove with a depth less than a height of the first end <NUM> protruding from the base wall <NUM>. As shown in <FIG>, a depth of the second opening B is h, and h is less than a height of the first end <NUM> protruding from the second part 332b.

In <FIG>, it can be seen that a lower edge of the second opening B protrudes from the base wall <NUM> of the first insulating member <NUM>, so that the side wall <NUM> can also continuously be arranged around outer periphery of the base wall <NUM> with the second opening B, so that the base wall <NUM> has the higher structural strength, is not easy to be deformed, and can better transmit force between the end cover <NUM> and the current collecting plate <NUM> or between the end cover <NUM> and the electrode assembly <NUM>.

In yet another embodiments, as shown in <FIG>, the second opening B on the first insulating member <NUM> is a hole formed by penetrating from one side of the side wall <NUM> to the other side, and a penetrating direction is perpendicular to the thickness direction of the end cover <NUM>. In this case, part of the second opening B is located at the second part 332b, or all of that is located at the second part 332b, so that the emissions may easily enter the first gap A through the second opening B.

The second opening B can be a polygonal hole formed through cutting on the side wall <NUM>, or can be a circular hole formed by drilling on the side wall <NUM>, or can be integrally formed during injection molding.

In some embodiments, the flow path may only include the second gap C formed between the outer peripheral surface of the first insulating member <NUM> and the inner wall of the housing <NUM>. Along the thickness direction D of the end cover, a projection of the second gap C on the end cover <NUM> along the thickness direction D of the end cover is staggered with the pressure relief mechanism <NUM>.

For example, as shown in <FIG>, the first insulating member does not include the side wall <NUM>, the outer peripheral surface of the first insulating member <NUM> (that is, an outer peripheral surface of the base wall <NUM>) is not in contact with the inner wall of the housing <NUM> at all, so as to form the second gap C.

Or, a part of the outer peripheral surface of the first insulating member <NUM> is not in contact with the inner wall of the housing <NUM> to form the second gap C. As shown in <FIG>, the outer peripheral surface of the first insulating member <NUM> at the first base 331a abuts against the inner wall of the housing <NUM>, and the outer peripheral surface at the second base 331b is not in contact with the inner wall of the housing <NUM>.

The second gap C not only allows the emissions to enter the first gap A through the second gap C when the internal pressure or temperature of the battery cell <NUM> reaches the predetermined threshold, but also ensures that the electrolytic solution cannot pass through the second gap C to directly impact the pressure relief mechanism <NUM>, so that the first insulating member <NUM> has an effect of protecting the pressure relief mechanism <NUM>.

In general, an air pressure value inside the battery cell <NUM> and at the first gap A is equal, but in the case of out-of-control gas production or abnormal temperature rise, air pressure inside the battery cell <NUM> increases sharply, and if the flow path cannot discharge the air pressure timely, the gas inside the battery cell <NUM> cannot quickly enter the first gap A, which can easily causes that the air pressure value inside the first gap A has not yet reached a valve opening pressure value of the pressure relief mechanism <NUM> (that is, a pressure value that causes the pressure relief mechanism <NUM> to be actuated) when a pressure value inside the battery cell <NUM> rises to a set limit pressure value (that is, a pressure value that may cause the battery cell <NUM> to explode). Generally speaking, the valve opening pressure value of the pressure relief mechanism <NUM> is usually about one half of the limit pressure value of the battery cell <NUM>. In order to ensure the safety of the battery cell <NUM>, a minimum ventilation area of the flow path is configured to be greater than or equal to one half of the area of the pressure relief mechanism <NUM>.

For ease of understanding, it is assumed that the limit pressure value of the battery cell <NUM> is 3Mpa and the valve opening pressure value of the pressure relief mechanism <NUM> is <NUM>. 5Mpa in the embodiment for illustration.

In the case that the air pressure is discharged timely, that is, when the minimum ventilation area of the flow path is at least the same as an exhaust area of the pressure relief mechanism <NUM>, the pressure value inside the battery cell <NUM> is equal to the pressure value in the first gap A, and when the pressure value inside the battery cell <NUM> reaches <NUM>. 5Mpa, the pressure relief mechanism <NUM> is actuated to ensure that the pressure value inside the battery cell <NUM> and the pressure value in the first gap A are always at <NUM>.

When the minimum ventilation area of the flow path is reduced relative to the exhaust area of the pressure relief mechanism <NUM>, rapid gas production can cause the pressure value inside the battery cell <NUM> to be greater than the pressure value in the first gap A.

If the minimum ventilation area of the flow path is smaller than the area of the pressure relief mechanism <NUM> and is greater than one half of the area of the pressure relief mechanism <NUM>, when the pressure value inside the battery cell <NUM> is greater than <NUM>. 5Mpa and less than 3Mpa, the pressure value in the first gap A reaches <NUM>. 5Mpa, so that the pressure relief mechanism <NUM> is actuated to prevent the battery cell <NUM> from exploding.

If the minimum ventilation area of the flow path is reduced to one half of the area of the pressure relief mechanism <NUM>, when the pressure value inside the battery cell <NUM> approaches the limit pressure value 3Mpa, the pressure value in the first gap A approaches <NUM>. 5Mpa, so that the pressure relief mechanism <NUM> is actuated to prevent the battery cell <NUM> from exploding when the pressure value inside the battery cell <NUM> exceeds 3Mpa.

In order to make the minimum ventilation area of the flow path greater than or equal to one half of the area of the pressure relief mechanism <NUM>: in an embodiment with the second opening B, the area of the second opening B is greater than or equal to one half of the area of the pressure relief mechanism <NUM>; and in an embodiment with the second gap C, the minimum ventilation area of the second gap C is greater than one half of the area of the pressure relief mechanism <NUM>.

The minimum ventilation area of the second gap C in the embodiment refers: a cross section is made along a radial direction of the battery cell <NUM>, when a cross-sectional area of the second gap C reaches its minimum, the cross-sectional area of the second gap C here is the minimum ventilation area.

The outer peripheral surface of the first insulating member <NUM> may be in contact with the housing <NUM> due to manufacturing errors, which blocks the second gap C and affects a normal operation of the pressure relief mechanism <NUM>. The outer peripheral surface of the first insulating member <NUM> is at least partially an inclined face, so that a width of the second gap C gradually increases along a direction away from the end cover <NUM>. At the same time, in the case that the minimum ventilation area does not change, the outer peripheral surface of the first insulating member <NUM> is configured as the inclined face, so the second gap C forms a shape with a relatively large inlet and a relatively small outlet, which is conducive that the emissions enter the second gap C and converge under an action of the pressure and then are discharged towards the outlet. The second gap C has a better drainage effect, stabilizes a discharge flow path of the emissions, increases a discharge rate, and enhances a pressure relief effect.

The second gap C extends at least from the lower edge of the second opening B to the second end <NUM>, and the closer the outer peripheral surface of the side wall <NUM> is to the second end <NUM>, the farther it is from the housing <NUM>. Taking <FIG> as an example, the lower edge of the second opening B refers to an edge of the second opening B away from the end cover <NUM>, the width of the second gap C here is k, and a difference between the width of the second gap C and k gradually increases along a direction away from the end cover <NUM>.

In some embodiments, the second gap C extends from the first end <NUM> to the second end <NUM>, that is, the outer peripheral surface of the first insulating member <NUM> is inclined from the first end <NUM> to the second end <NUM>, so as to further avoid blocking the second opening B caused by contact between the outer peripheral surface of the first insulating member <NUM> and the housing <NUM> due to manufacturing tolerances.

In some embodiments, the side wall <NUM> can be configured in a conical shape, and the second gap C is formed between the entire side wall <NUM> and the housing <NUM> to communicate the inside of the battery cell <NUM> with the first gap A.

In other embodiments, the side wall <NUM> can be configured to form the inclined face only on the outer peripheral surface of a position corresponding to the second opening B, so that the first part 332a of the side wall <NUM> abuts against the housing <NUM> to improve assembling stability of the first insulating member <NUM>, and the second gap C is formed between the second part 332b and the housing <NUM> to communicate the inside of the battery cell <NUM> with the first gap A.

In some embodiments, the end cover <NUM> abuts against the electrode assembly <NUM> through the current collecting plate <NUM>, but sometimes there is a gap between each connection section of the current collecting plate <NUM>, causing that the electrode assembly <NUM> may still slosh. As shown in <FIG>, the side wall <NUM> is configured that the first end <NUM> abuts against the end cover <NUM> and the second end <NUM> abuts against the electrode assembly <NUM>, so that end cover <NUM> directly presses the electrode assembly <NUM> through the side wall <NUM>, thereby further defining a movement of the electrode assembly <NUM>.

When the first end <NUM> abuts against the end cover <NUM>, the first end <NUM> is close to a welding seam at junction of the housing <NUM> and the end cover <NUM>, and when welding the housing <NUM> and the end cover <NUM>, the first end <NUM> of the first insulating member <NUM> is easy to be deformed by high heat. In some embodiments, a corner at intersection of an end surface of the first end <NUM> and the outer peripheral surface of the first end <NUM> is chamfered or cut to be recessed from a surface of the first end <NUM>, so as to form a spacing between the welding seam and the first end <NUM> of the side wall <NUM>. Due to an effect of the spacing, the first end <NUM> is not easy to be burned during a process of welding the junction of the housing <NUM> and the end cover <NUM> at high temperature to form the welding seam, which prevents the side wall <NUM> from being thermally deformed at the high temperature generated during the welding, solves a problem that the side wall <NUM> cannot abut against the end cover <NUM> and the electrode assembly <NUM> due to thermal damage and deformation, and avoids a poor constraint of the electrode assembly <NUM>.

When the emissions need to travel a long distance from the inside of the battery cell <NUM> to the pressure relief mechanism <NUM>, a response speed of the pressure relief mechanism <NUM> is relatively low. In some embodiments, as shown in a combination of <FIG>, a central angle corresponding to a projection of the second opening B or the second gap C on the end cover <NUM> at least partially overlaps with a part of a central angle corresponding to the pressure relief mechanism <NUM> along the thickness direction D of the end cover.

A projection of the second opening B on the end cover <NUM> is formed in an arc, a central angle corresponding to the arc is α, and two radius of the end cover <NUM> pass through two ends of the arc and form a fan shape with the arc. The pressure relief mechanism <NUM> is located within a fan-shaped range, which makes a distance from the second opening B to the pressure relief mechanism <NUM> become shorter, and the emissions can smoothly and quickly reach the pressure relief mechanism <NUM> to improve the response speed of the pressure relief mechanism. Here, the second opening B is taken as an example for description, and the second gap C is the same.

In some embodiments, the first protrusion is a polygon, the plurality of second protrusions are arranged at corners of the polygon, respectively, and each second protrusion is configured to abut against two faces forming the corners. In some embodiments, a corner of the first protrusion is chamfered to form a curved surface, and the surface of the second protrusion has the same curvature as the curved surface.

In an embodiment, the electrode terminal <NUM> is located at the first protrusion, a thickness of the end cover <NUM> is relatively large at the first protrusion, and by arranging the electrode terminal <NUM> at the first protrusion, a length of the electrode terminal <NUM> passing through the end cover <NUM> can be increased, and the assembly of the electrode terminal <NUM> is more stable.

The first insulating member <NUM> is formed with a through hole that allows the electrode terminal <NUM> to pass through to connect the current collecting plate <NUM>, and when the electrode terminal <NUM> is located at the first protrusion, the through hole is arranged in a range surrounded by the plurality of second protrusions for accommodating the first protrusion. That is, the plurality of second protrusions not only surround and abut against the first protrusion, but also surround a peripheral direction of the electrode terminal <NUM>. When an end of the electrode terminal <NUM> extending out of the end cover <NUM> is moved or impacted, the plurality of the second protrusion provides reaction force through the first protrusion at a periphery of the electrode terminal <NUM>, and the first protrusion bears force together with the electrode terminal <NUM> to alleviate bend and deformation of the electrode terminal <NUM>.

In some embodiments, the first positioning portion <NUM> may also be configured as a recess formed on one side of the end cover <NUM> facing the electrode assembly <NUM>, and the recess is matched with the first protrusion on the base wall <NUM>. Of course, the first positioning portion <NUM> may also be configured as a protrusion formed on one side of the end cover <NUM> facing the electrode assembly <NUM>, and the second positioning portion <NUM> is configured as a recess formed on one side of the base wall <NUM> facing the end cover <NUM>.

In some embodiments, the second positioning portion <NUM> may also be formed on the end surface of the first end <NUM> of the side wall <NUM>, and when the first end <NUM> abuts against the end cover <NUM>, the second positioning portion <NUM> formed on the first end <NUM> is matched with the first positioning portion <NUM> on the end cover <NUM>.

The battery cell <NUM>, the battery <NUM> and the power consumption apparatus of the embodiments of the present application are described above, and a method and an apparatus for producing a battery cell <NUM> according to the embodiments of the present application will be described below. For the parts that are not described in detail, reference is made to the foregoing embodiments.

<FIG> shows a schematic flowchart of a method for producing a battery cell <NUM> according to an embodiment of the present application, and the method can include:.

<FIG> shows a schematic block diagram of an apparatus <NUM> for producing a battery cell <NUM> according to an embodiment of the present application, and the apparatus <NUM> for producing can include: a first providing apparatus <NUM>, a second providing apparatus <NUM>, a third providing apparatus <NUM> and an assembling apparatus <NUM>.

The first providing apparatus <NUM>, configured to provide a housing <NUM>, and the housing <NUM> has a first opening <NUM>;.

Claim 1:
A battery cell (<NUM>), comprising:
a housing (<NUM>), being a hollow cylinder with a first opening (<NUM>);
an electrode assembly (<NUM>), arranged in the housing (<NUM>);
an end cover assembly (<NUM>), comprising an end cover (<NUM>), a pressure relief mechanism (<NUM>) and a first insulating member (<NUM>), the end cover (<NUM>) covers the first opening (<NUM>), the pressure relief mechanism (<NUM>) is arranged at the end cover (<NUM>), the pressure relief mechanism (<NUM>) is configured to be actuated to relieve the internal pressure of the battery cell (<NUM>) when an internal pressure or temperature of the battery cell (<NUM>) reaches a threshold, the first insulating member (<NUM>) is located on a side of the end cover (<NUM>) close to the electrode assembly (<NUM>) to isolate the electrode assembly (<NUM>) and the end cover (<NUM>), and the first insulating member (<NUM>) is configured that a projection of the first insulating member on the end cover (<NUM>) along a thickness direction (D) of the end cover (<NUM>) covers a projection of the pressure relief mechanism (<NUM>) on the end cover (<NUM>) along a thickness direction (D) of the end cover (<NUM>) to protect the pressure relief mechanism (<NUM>);
wherein the pressure relief mechanism (<NUM>) and the first insulating member (<NUM>) are provided with a first gap (A) in the thickness direction (D) of the end cover (<NUM>), the battery cell (<NUM>) further comprises a flow path, and the flow path is configured to communicate the inner portion of the battery cell (<NUM>) and the first gap (A);
wherein the flow path comprises a second opening (B) arranged on the first insulating member (<NUM>), and the second opening (B) is configured that a projection of the second opening on the end cover (<NUM>) along the thickness direction (D) of the end cover (<NUM>) is staggered with the pressure relief mechanism (<NUM>);
wherein a projection of the second opening (B) on the end cover (<NUM>) is formed in an arc, and two radius of the end cover (<NUM>) pass through two ends of the arc and form a fan shape with the arc, the pressure relief mechanism (<NUM>) is located within the fan-shaped range.