Batteries and Power Consuming Devices

Abstract

An embodiment of the present application provides a battery and a power consumption device. The battery includes a housing, a battery unit, and a protective member. The housing includes a first wall. The battery unit is accommodated in the housing, and a pressure relief mechanism is provided in the battery unit, and the pressure relief mechanism is used to form a pressure relief hole and release a substance inside the battery unit. The protective member is accommodated in the housing, and at least a part of the protective member is located between the first wall and the pressure relief mechanism and is used to cover the pressure relief hole in an axial direction of the pressure relief hole. The minimum size along the axial direction of the part of the protective member that covers the pressure relief hole in the axial direction is D, and the flow rate of gas released by the battery unit through the pressure relief hole is G, and D and G are less than or equal to 2×10 -3 mm s / L≦D / G≦3.3×10 -1 mm s / L. The embodiment of the present application can reduce the redundancy in the size design of the protective member while still meeting the thermal protection requirements, thereby reducing the loss of energy density of the battery and improving the safety of the battery.

Description

[Technical field]

[0001] TECHNICAL FIELD This application relates to the field of battery technology, and more specifically, to batteries and power consuming devices. [Background technology]

[0002] Batteries are widely used in electronic devices, such as mobile phones, notebook computers, battery cars, electric cars, electric airplanes, electric steamships, electric toy cars, electric toy steamships, electric toy airplanes and electric tools.

[0003] How to improve the safety of batteries is a research direction in battery technology. Summary of the Invention

[0004] The present application provides batteries and power consuming devices that can improve safety.

[0005] According to a first aspect, an embodiment of the present application provides a battery including a housing, a battery unit, and a protective member. The housing includes a first wall. The battery unit is housed in the housing, and a pressure release mechanism is provided in the battery unit, and the pressure release mechanism is used to form a pressure release hole and release a substance inside the battery unit. The protective member is housed in the housing, and at least a part of the protective member is located between the first wall and the pressure release mechanism and is used to cover the pressure release hole in the axial direction of the pressure release hole. The minimum size along the axial direction of the part of the protective member that covers the pressure release hole in the axial direction is D, and the flow rate of gas released by the battery unit through the pressure release hole is G, and D and G are less than or equal to 2×10 -3 mm s / L≦D / G≦3.3×10 -1 Meets mm s / L.

[0006] The higher the flow rate G of the gas generated when the battery unit experiences thermal runaway, the greater the thermal shock of the gas that the protective member receives, and the higher the demand for D of the protective member. Conversely, the lower the flow rate G of the gas generated when the battery unit experiences thermal runaway, the smaller the thermal shock of the gas that the protective member receives, and the lower the demand for D of the protective member. When the flow rate G is determined, it is necessary to guarantee a minimum value of D in order to reduce the risk of the protective member being broken through and to reduce the amount of heat transferred to the first wall. Of course, the larger the value of D, the greater the volume and weight of the protective member. When the flow rate G is determined, the redundancy of the size design of the protective member may be reduced by limiting the maximum value of D. The above technical proposal sets the value of D / G at 2×10 -3 mm s / L-3.3×10 -1 By limiting it to mm·s / L, the redundancy in the size design of the protective components can be reduced while still meeting thermal protection requirements, minimizing the loss of battery energy density and improving battery safety.

[0007] In some embodiments, D and G are 2×10 -3 mm s / L≦D / G≦2×10 -1 Meets mm s / L.

[0008] In some embodiments, the value of D is 0.5 mm to 5 mm, which reduces the redundancy of the size design of the protective member while maintaining compatibility with thermal protection requirements, reduces the loss of energy density of the battery, reduces the difficulty of molding the protective member, and improves the safety of the battery.

[0009] In some embodiments, the size of the protection member is larger than the size of the pressure relief hole in any direction perpendicular to the axial direction. The protection member has a relatively large size compared to the pressure relief hole, which can effectively block the gas, reduce the risk of the gas directly colliding with the first wall, and improve safety.

[0010] In some embodiments, the volumetric energy density of the battery unit is E, and D and E are less than or equal to 1×10 -3 mm L / Wh≦D / E≦1×10-2 Meet mm L / Wh.

[0011] In principle, the volumetric energy density E of a battery unit has a positive correlation with the flow rate G, and the volumetric energy density E of a battery unit is easier to determine than the flow rate G. The above technical solution indirectly characterizes the flow rate G with the volumetric energy density E, and limits the value of D with the volumetric energy density E, thereby reducing the redundancy of the size design of the protective member under the premise of compatibility with thermal protection requirements, reducing the loss of the battery energy density, and easing the difficulty of designing the protective member.

[0012] In some embodiments, D and E are 1×10 -3 mm L / Wh≦D / E≦6×10 -3 Meet mm L / Wh.

[0013] In some embodiments, the size of the pressure relief hole in the maximum size direction perpendicular to the axial direction of the pressure relief hole is k, and the size of the protective member along the maximum size direction is K, where k, K, and G are K>k, (K / k) / G≧3×10 -3 Meet s / L.

[0014] The higher the flow rate G of the gas generated when the battery unit experiences thermal runaway, the greater the thermal shock to the protective member caused by the gas released by the battery unit, which increases the risk that the gas and other carried substances will be scattered to the part of the first wall not shielded by the protective member, and the higher the temperature of the part of the first wall not shielded by the protective member. The above technical solution limits the size relationship between the protective member and the pressure relief hole in the maximum size direction based on the flow rate G of the gas generated when the battery unit experiences thermal runaway, thereby keeping the temperature of the part of the first wall not shielded by the protective member within a certain range, thereby reducing the risk of damage to the first wall.

[0015] In some embodiments, k, K, and G are such that (K / k) / G≧8×10 -3 Meet s / L.

[0016] In some embodiments, k, K, and G satisfy (K / k) / G≦20s / L. This technical solution can reduce the redundancy of the size design of the protective member and reduce the loss of the energy density of the battery.

[0017] In some embodiments, the minimum axial distance between the protective member and the pressure relief hole is h, and h and D satisfy 0.2≦h / D≦250. By limiting the value of h / D to 0.2-250, the redundancy of the size design of the protective member can be reduced under the premise of meeting the thermal protection requirements, and the loss of the energy density of the battery can be reduced, and the safety of the battery can be improved.

[0018] In some embodiments, the protective member has a flat plate structure, and the thickness direction of the protective member is parallel to the axial direction. The flat plate structure is easy to mold.

[0019] In some embodiments, in the maximum size direction perpendicular to the axial direction of the pressure relief hole, the thickness of the protective member gradually decreases from the middle to both sides, and the thickness direction of the protective member is parallel to the axial direction.

[0020] The thickest part of the protective member covers at least a part of the pressure relief hole in the axial direction. The thickest part of the protective member faces the pressure relief hole, which can withstand a relatively large thermal shock and reduce the risk of the protective member being broken through. The thermal shock experienced by both ends of the protective member is relatively small, and the protective member can have a relatively small thickness, which reduces the weight and volume of the protective member and improves the energy density of the battery.

[0021] In some embodiments, the protective member includes a base region and a reinforcing region connected to the base region, and the reinforcing region has an axial size larger than the axial size of the base region. In the axial direction, the reinforcing region covers at least a part of the pressure relief hole. The reinforcing region faces the pressure relief hole, which can withstand a relatively large thermal shock and reduces the risk of the protective member being broken through.

[0022] In some embodiments, the reinforcement region completely covers the pressure relief hole in the axial direction. The reinforcement region can withstand a relatively large thermal shock, thereby reducing the risk of the protective member being broken through. The base region does not face the pressure relief hole in the axial direction, and it may have a relatively small thickness in order to reduce the weight and volume of the protective member and improve the energy density of the battery.

[0023] In some embodiments, in the maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the protective member is K, and the size of the reinforcement region is K1. K, K1, and G are K>K1, (K / K1) / G≦2×10 -1 Meet s / L.

[0024] The higher the flow rate G of gas generated when the battery unit undergoes thermal runaway, the greater the thermal shock to the protective member caused by the gas emitted by the battery unit, and the higher the size requirement for the reinforcement area of ​​the protective member. -1 By limiting the thickness to s / L or less, the reinforcement region and the base region can block the high-temperature, high-velocity material, thereby reducing the amount of heat transferred to the first wall and decreasing the temperature of the first wall.

[0025] In some embodiments, both the reinforcement region and the base region have a flat plate structure, and the thickness direction of the reinforcement region and the thickness direction of the base region are both parallel to the axial direction.

[0026] In some embodiments, the size of the reinforcement region along the axial direction is D, and the size of the base region along the axial direction is d. In the maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the pressure relief hole is k, and the size of the reinforcement region is K1. D, d, k, and K1 satisfy 0.04≦(K1 / k) / (D / d)≦300.

[0027] With an increase in the K1 / k value, the proportion of thermal shock that the reinforcement region receives when the battery unit undergoes thermal runaway increases, and the thermal runaway protection requirement that the base region needs to meet decreases, and the ratio of D / d may increase accordingly, i.e., the thickness requirement of the base region may decrease. With a decrease in the K1 / k value, the thermal runaway protection requirement that the base region needs to meet increases, and the ratio of D / d may decrease accordingly, i.e., the thickness requirement of the base region increases. When K1 / k is sufficiently small, the thermal runaway protection requirement that the base region needs to meet is relatively large, and there is a minimum value for D / d, i.e., there is a maximum value for d, thereby satisfying the thermal runaway protection requirement of the base region; when K1 / k is sufficiently large, the thermal runaway protection requirement that the base region needs to meet is relatively small, and there is a maximum value for D / d, i.e., there is a minimum value for d. By limiting the value of (K1 / k) / (D / d) to 0.04-300, the redundancy in the size design of the protective components can be reduced while still meeting thermal protection requirements, thereby reducing the loss of battery energy density and improving battery safety.

[0028] In some embodiments, the protective member includes a first protective plate and a second protective plate that are stacked along the axial direction, a portion where the first protective plate and the second protective plate overlap in the axial direction and the second protective plate constitute a reinforcement region, and a portion where the first protective plate and the second protective plate do not overlap in the axial direction constitutes a base region. The first protective plate and the second protective plate are stacked to form a protective member having a difference in thickness, which simplifies the molding process of the protective member.

[0029] In some embodiments, the second protective plate is installed on one side of the first protective plate facing the pressure relief mechanism, which can improve the flatness of the one side of the protective member facing away from the pressure relief mechanism, and facilitate the fixing of the protective member to other members.

[0030] In some embodiments, the second guard plates are multiple and the multiple second guard plates are spaced apart.

[0031] In some embodiments, the second guard plates are spaced apart in a maximum size direction perpendicular to the axial direction of the pressure relief hole.

[0032] In some embodiments, the first protective plate and the second protective plate both have a flat plate structure, and the thickness direction of the first protective plate and the thickness direction of the second protective plate are both parallel to the axial direction.

[0033] In some embodiments, the first protective plate has a flat plate structure, and the thickness direction of the first protective plate is parallel to the axial direction. In the maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the second protective plate along the axial direction gradually decreases from the middle to both ends.

[0034] The largest portion of the second protective plate in the axial direction may face the pressure relief hole, thereby reducing the risk of the protective member being broken through due to a relatively large thermal shock. The thermal shock experienced by both ends of the second protective plate is relatively small, and the second protective plate may have a relatively small thickness in order to reduce the weight and volume of the second protective plate and improve the energy density of the battery.

[0035] In some embodiments, the material of the second protective plate is different from the material of the first protective plate. The first protective plate and the second protective plate are made of different materials, and the characteristics of the different materials can be combined to compound a protective member with higher thermal shock resistance. Compared with the first protective plate and the second protective plate made of the same material, the first protective plate and the second protective plate made of different materials can make the structure of the protective member more varied.

[0036] In some embodiments, the first wall is located above or below the battery unit.

[0037] In some embodiments, the melting point of the protective member is higher than 1000° C. The protective member has a relatively high melting point, which is less likely to melt when subjected to thermal shock, so that the protective member has relatively good thermal shock resistance performance and reduces the risk of the protective member being pierced.

[0038] In some embodiments, the melting point of the protective member is higher than the melting point of the first wall, so that the protective member has better thermal shock resistance performance against the first wall, thereby performing a thermal protective function and reducing the risk of the first wall being damaged.

[0039] In some embodiments, the protective member is fixed to the first wall, which can fix the protective member, thereby reducing the risk of the protective member moving around due to the impact of high temperature, high velocity gas, reducing the probability of the protective member being damaged by collision, and reducing the risk of the protective member losing its protection.

[0040] In some embodiments, the guard member is secured to the first wall by adhesive, welding, fastener connection, or locking.

[0041] According to a second aspect, an embodiment of the present application provides a power consuming device, the power consuming device comprising a battery of any of the embodiments of the first aspect for providing electrical energy. [Brief description of the drawings]

[0042] In order to more clearly explain the technical solutions of the embodiments of the present application, the following briefly introduces drawings that need to be used in the embodiments of the present application. It is obvious that the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings based on the drawings without exerting creative efforts. [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Diagram 2] FIG. 1 is an exploded schematic diagram of a battery according to some embodiments of the present application. [Diagram 3] FIG. 1 is a structural schematic diagram of a battery according to some embodiments of the present application. [Figure 4] FIG. 4 is another structural schematic diagram of the battery shown in FIG. 3, in which the pressure relief mechanism of the battery unit of the battery is in an operating state; [Diagram 5]5 is an enlarged schematic view of the battery shown in FIG. 4 in a circular frame A. FIG. [Figure 6] 1 is a structural schematic diagram of a battery unit of a battery according to some embodiments of the present application. [Figure 7] FIG. 1 is a structural schematic diagram of a battery according to some embodiments of the present application. [Figure 8] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application. [Figure 9] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application. [Figure 10] FIG. 10 is an enlarged schematic view of block B in FIG. [Figure 11] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application. [Figure 12] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application. [Figure 13] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application. [Figure 14] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application. [Figure 15] FIG. 2 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0043] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained based on the embodiments of the present application without the need for creative efforts by those skilled in the art are all within the scope of protection of the present application.

[0045] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the art in the technical field of this application, and the terms used in the specification of this application are only for describing specific embodiments and are not intended to limit this application, and the terms "comprises" and "has" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive "comprises". The terms "first", "second", etc. in the specification and claims of this application or the above drawings are not intended to describe a specific order or subordinate relationship, but are intended to distinguish different objects.

[0046] An "embodiment" referred to in this application means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they mutually exclusive separate or alternative embodiments of other embodiments.

[0047] In the description of the present application, it should be explained that unless otherwise clearly defined or limited, the terms "attached", "connected", "connected" and "attached" should be understood in a broad sense, for example, may be a fixed connection, a removable connection, or an integral connection, may be a direct connection, may be an indirect connection through an intermediate medium, or may be communication between the insides of two elements. Those skilled in the art can understand the specific meaning of the above terms in the present application according to the specific situation.

[0048] The term "and / or" in this application merely describes the relationship between related objects and indicates that three relationships may exist, for example, A and / or B may represent three cases: A alone, A and B in combination, and B alone. In addition, the character " / " in this application generally indicates that the related objects before and after are in an "or" relationship.

[0049] In the embodiments of the present application, the same reference numerals denote the same components, and detailed descriptions of the same components in different embodiments are omitted for the sake of brevity. It should be understood that the dimensions of thickness, aspect, etc. of various components in the embodiments of the present application shown in the drawings, and the dimensions of thickness, aspect, etc. of the entire integrated device are only illustrative descriptions, and do not constitute any limitations on the present application.

[0050] The term "plurality" as used herein refers to two or more (including two).

[0051] In this application, the term "parallel" includes not only absolute parallelism but also approximately parallelism as generally recognized in engineering, and the term "perpendicular" includes not only absolute perpendicularity but also approximately perpendicularity as generally recognized in engineering.

[0052] In the present application, the battery unit may include a lithium ion battery unit, a lithium sulfur battery unit, a sodium lithium ion battery unit, a sodium ion battery unit, or a magnesium ion battery unit, etc., and the embodiments of the present application are not limited thereto. The battery unit may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, and the embodiments of the present application are not limited thereto.

[0053] The battery referred to in the embodiments of this application is a single physical module that includes one or more battery units to provide higher voltage and capacity. The battery generally includes a housing for packaging one or more battery units. The housing can prevent liquid or other foreign matter from affecting the charging or discharging of the battery unit.

[0054] The development of battery technology requires simultaneous consideration of a wide range of design factors, such as performance parameters such as energy density, cycle life, discharge capacity, and charge / discharge ratio, as well as battery safety.

[0055] The pressure relief mechanism of a battery unit has an important impact on the safety of the battery unit. For example, when a short circuit or overcharging occurs, a sudden increase in pressure may occur due to thermal runaway inside the battery unit. In such a case, the pressure relief mechanism is activated to release the internal pressure to the outside in order to prevent the battery unit from exploding or catching fire.

[0056] The pressure relief mechanism may be an element or member that operates when the battery unit reaches a certain condition. Exemplarily, the pressure relief mechanism may be an element or member that operates to release internal pressure and / or internal material when the internal pressure or internal temperature of the battery unit reaches a predetermined threshold. The threshold design varies according to design needs. The threshold may depend on one or more materials of the positive electrode plate, the negative electrode plate, the electrolyte, and the separator member in the battery unit.

[0057] The pressure relief mechanism can take the form of an explosion-proof valve, an air valve, a pressure relief valve, a safety valve, etc., and can specifically use a pressure-sensitive element or structure, i.e., when the internal pressure of the battery unit reaches a predetermined threshold, the pressure relief mechanism performs an operation, or a weak area provided in the pressure relief mechanism bursts, thereby forming a pressure relief hole that can release the internal pressure. Alternatively, the pressure relief mechanism can use a temperature-sensitive element or structure, i.e., when the internal temperature of the battery unit reaches a predetermined threshold, the pressure relief mechanism performs an operation, thereby forming a pressure relief hole for releasing the internal pressure. Alternatively, the pressure relief mechanism can be an actively operable member, and for example, the pressure relief mechanism can be operated when it receives a control signal from the battery.

[0058] The pressure relief mechanism may take other forms. For example, the pressure relief mechanism may be a structure with a relatively low strength on the housing of the battery unit, and when the battery unit experiences thermal runaway, the structure with a relatively low strength cracks or deforms to form a pressure relief hole for releasing the internal pressure. For example, the pressure relief mechanism may be a solder mark on the housing of the battery unit.

[0059] "Operation" as referred to in this application means that the pressure relief mechanism operates or is activated to a certain state, thereby releasing the internal pressure and / or internal material of the battery unit. The operation by the pressure relief mechanism may include, but is not limited to, rupturing, crushing, tearing, or opening at least a portion of the pressure relief mechanism. When the pressure relief mechanism operates, the high-temperature, high-velocity material inside the battery unit is discharged from the operating portion as a discharge. If the pressure can be controlled in this manner, the occurrence of a potentially more serious accident can be avoided by having the battery unit release pressure.

[0060] The discharged materials from the battery unit referred to in this application include, but are not limited to, electrolyte, melted or split positive and negative electrodes, pieces of separator members, high temperature and high velocity gases generated by reactions, flames, etc.

[0061] When the battery unit experiences thermal runaway, the battery unit releases waste materials into the housing. The housing is also provided with a pressure relief mechanism, and the pressure relief mechanism of the housing is activated to discharge the waste materials outside the housing at a set position.

[0062] The inventors realized that the exhaust material discharged from the battery unit is in a high-temperature and high-velocity state, and when the exhaust material collides with the housing, it may cause damage to the housing, and the exhaust material will not be released through the pressure release mechanism of the housing, but will be released through the broken point of the housing, thereby creating a risk of fire outside the battery and posing a safety risk.

[0063] After discovering the above problem, the inventor attempted to install a protective member in a position opposite the pressure relief mechanism of the battery unit. The protective member can block the high-temperature, high-velocity substances released by the battery unit, thereby reducing the thermal shock received by the housing, reducing the risk of damage to the housing, and improving safety.

[0064] The inventors have found through research that when the battery unit undergoes thermal runaway, if the battery unit generates too much gas, the protective member, which has a relatively small thickness, may be hit by the high-temperature, high-velocity gas released from the battery unit, forming a hole in the protective member, which may allow the high-temperature, high-velocity gas to hit the housing through the hole, causing a risk of damage to the housing. In order to reduce the risk of the protective member being broken through by the gas, the inventors have tried to increase the size of the protective member, but increasing the size of the protective member reduces the energy density of the battery, and if the size of the protective member is overdesigned, energy density is wasted.

[0065] In light of this, the inventor has provided a technical proposal that reduces the risk of the protective member being melted and penetrated and reduces waste of the battery's energy density by setting the size of the protective member according to the flow rate of gas released by the battery unit.

[0066] The technical solutions described in the embodiments of the present application are applied to power consuming devices that use batteries.

[0067] The power consumption device may be a vehicle, a mobile phone, a portable device, a notebook computer, a steamship, a spacecraft, an electric toy and an electric tool, etc. The vehicle may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range extender vehicle, etc., the spacecraft includes an airplane, a rocket, a space shuttle and a spaceship, etc., the electric toy includes a stationary or mobile electric toy, such as a game console, an electric car toy, an electric steamship toy and an electric airplane toy, etc., and 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 electric impact drill, a concrete vibrator and an electric planer, etc. The embodiment of the present application does not particularly limit the above power consumption device.

[0068] In the following embodiment, for convenience of explanation, the power consuming device will be described as a vehicle.

[0069] FIG. 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application.

[0070] 1, a battery 2 is installed inside the vehicle 1, and the battery 2 may be installed at the bottom, head, or tail of the vehicle 1. The battery 2 may be used to supply power to the vehicle 1, for example, the battery 2 may be used as an operating power source for the vehicle 1.

[0071] The vehicle 1 may further include a controller 3 and a motor 4, the controller 3 being used to control the battery 2 to power the motor 4 for use in, for example, starting the vehicle 1, navigation and operating power consumption needs during driving.

[0072] In some embodiments of the present application, the battery 2 can be used not only as an operating power source for the vehicle 1, but also as a drive power source for the vehicle 1, providing drive power to the vehicle 1 in place of, or in place of, gasoline or natural gas.

[0073] FIG. 2 is an exploded schematic diagram of a battery according to some embodiments of the present application.

[0074] As shown in FIG. 2, the battery 2 includes a housing 20 and a battery unit 10 , and the battery unit 10 is housed within the housing 20 .

[0075] The housing 20 is used to house the battery unit 10, and the housing 20 may have various structures. In some embodiments, the housing 20 may include a first housing portion 21 and a second housing portion 22, where the first housing portion 21 and the second housing portion 22 are fitted over each other, and the first housing portion 21 and the second housing portion 22 together define a housing space for housing the battery unit 10.

[0076] In some embodiments, the second housing part 22 may be a hollow structure with one end open, and the first housing part 21 is a plate-like structure, and the first housing part 21 covers the open side of the second housing part 22, thereby forming the housing 20 having the storage space. In other embodiments, the first housing part 21 and the second housing part 22 may both be hollow structures with one end open, and the open side of the first housing part 21 covers the open side of the second housing part 22, thereby forming the housing 20 having the storage space.

[0077] The first housing part 21 and the second housing part 22 may have various shapes, for example, a cylinder, a rectangular parallelepiped, etc.

[0078] In order to improve the sealing property after the first housing part 21 and the second housing part 22 are connected, a sealing material may be installed between the first housing part 21 and the second housing part 22, for example, a sealant, a seal ring, etc. may be installed.

[0079] Assuming that the first housing part 21 is placed on top of the second housing part 22, the first housing part 21 is also called the upper housing cover, and the second housing part 22 is also called the lower housing 20.

[0080] In the battery 2, the battery unit 10 may be one or more. When there are more than one battery unit 10, the battery units 10 may be connected in series, in parallel, or in series-parallel, and the series-parallel connection means that the battery units 10 are connected in series or in parallel. The battery units 10 may be directly connected in series, in parallel, or in series-parallel, or the battery units 10 may be housed in a housing 20 as a whole. Of course, the battery units 10 may first be connected in series, in parallel, or in series-parallel to form a battery module, and the battery modules may be further connected in series, in parallel, or in series-parallel to form a battery module and housed in the housing 20.

[0081] FIG. 3 is a structural schematic diagram of a battery according to some embodiments of the present application, FIG. 4 is another structural schematic diagram of the battery shown in FIG. 3, where the pressure relief mechanism of the battery unit of the battery is in an operating state, FIG. 5 is an enlarged schematic diagram of the battery in the circular frame A shown in FIG. 4, FIG. 6 is a structural schematic diagram of the battery unit of the battery according to some embodiments of the present application, and FIG. 7 is a structural schematic diagram of a battery according to some embodiments of the present application.

[0082] As shown in Figs. 3 to 7, the battery 2 of the embodiment of the present application includes a housing 20, a battery unit 10, and a protective member 30. The housing 20 includes a first wall 21a. The battery unit 10 is housed in the housing 20, and a pressure release mechanism 11 is provided in the battery unit 10. The pressure release mechanism 11 forms a pressure release hole 111 and is used to release substances inside the battery unit 10. The protective member 30 is housed in the housing 20, and at least a part of the protective member 30 is located between the first wall 21a and the pressure release mechanism 11 and is used to cover the pressure release hole 111 in the axial direction Z of the pressure release hole 111. The minimum size of the part of the protective member 30 covering the pressure release hole 111 in the axial direction Z is D, the flow rate of gas released by the battery unit 10 through the pressure release hole 111 is G, and D and G are 2 x 10 -3 mm s / L≦D / G≦3.3×10 -1 Meets mm s / L.

[0083] The housing 20 may be an outer casing of the battery 2, and the battery unit 10 is located inside the casing. The housing 20 can prevent liquid or other foreign matter from affecting the charging or discharging of the battery unit 10.

[0084] The first wall 21a of the housing 20 is a wall facing the pressure relief mechanism 11 in the axial direction Z of the housing 20. The first wall 21a may be a top wall of the housing 20 located above the battery unit 10, a bottom wall of the housing 20 located below the battery unit 10, or a side wall of the housing 20 located on one side of the battery unit 10, and of course the first wall 21a may be a wall located at another position of the housing 20. Exemplarily, the first wall 21a may be a part of the first housing part or a part of the second housing part.

[0085] This embodiment does not limit the shape of the first wall 21a. For example, the first wall 21a may have a flat plate shape, a curved plate shape, or other shapes.

[0086] There may be one or more battery units 10. Exemplarily, there are multiple battery units 10. Optionally, the pressure relief mechanisms 11 of the multiple battery units 10 all face the first wall 21a.

[0087] The battery unit 10 includes one or more battery cells. A battery cell is the smallest unit constituting a battery and can independently realize the functions of charging and discharging. The battery cells may be cylindrical battery cells, prismatic battery cells, soft package battery cells, or other battery cells.

[0088] The battery cell includes a battery cell housing, an electrode assembly 13, an electrolyte, and other functional components, with the electrode assembly 13 and the electrolyte contained within the battery cell housing.

[0089] Exemplarily, the electrode assembly includes a positive electrode plate, a negative electrode plate, and a separator member. The battery cell is operated mainly by the movement of metal ions between the positive electrode plate and the negative electrode plate. The positive electrode plate includes a positive electrode collector and a positive electrode active material layer, the positive electrode active material layer is applied to the surface of the positive electrode collector, the positive electrode collector includes a positive electrode collector and a positive electrode tab, the positive electrode collector is applied with the positive electrode active material layer, and the positive electrode tab is not applied with the positive electrode active material layer. Taking a lithium-ion battery cell as an example, the material of the positive electrode collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganate, etc. The negative electrode plate includes a negative electrode collector and a negative electrode active material layer, the negative electrode active material layer is applied to the surface of the negative electrode collector, the negative electrode collector includes a negative electrode collector part and a negative electrode tab, the negative electrode collector part is applied with the negative electrode active material layer, and the negative electrode tab is not applied with the negative electrode active material layer. The material of the negative electrode collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon or silicon, etc. The material of the separator member may be PP (polypropylene) or PE (polyethylene), etc. The battery cell housing may be a hard housing, for example, the battery cell housing may be made of an aluminum alloy, and the battery cell housing may be a soft housing, for example, the battery cell housing may be made of an aluminum plastic film.

[0090] In some examples, the battery unit 10 may be a single battery cell, the housing 12 of the battery unit 10 may be a battery cell housing, and the pressure relief mechanism 11 may be disposed in the housing 12. In other examples, the battery unit 10 may include a housing 12 and a plurality of battery cells housed within the housing 12, and the pressure relief mechanism 11 may be disposed in the housing 12.

[0091] Illustratively, the housing 12 of the battery unit 10 includes a second wall 12a facing the first wall 21a, and the pressure relief mechanism 11 is attached to the second wall 12a, which is located on one side facing the first wall 21a of the electrode assembly 13. The pressure relief mechanism 11 may be fixed to the second wall 12a by welding, adhesive or other methods, or alternatively, the pressure relief mechanism 11 and the second wall 12a may be integrally formed.

[0092] When the battery unit 10 is in a normal state, the pressure release mechanism 11 does not form the pressure release hole 111. The pressure release mechanism 11 reduces the risk of electrolyte leakage by sealing the electrode assembly 13 and the electrolyte of the battery unit 10 inside the battery unit 10. When thermal runaway occurs inside the battery unit 10, the pressure release mechanism 11 operates to form the pressure release hole 111, and materials inside the battery unit 10 can be released to the outside of the battery unit 10 through the pressure release hole 111.

[0093] For example, the substance discharged through the pressure relief hole 111 includes high-temperature, high-velocity gas. The pressure relief hole 111 limits the flow direction of the gas, causing a portion of the gas to be ejected along the axial direction Z of the pressure relief hole 111.

[0094] The entire protective member 30 may be located between the first wall 21a and the pressure relief mechanism 11, or only a portion of the protective member 30 may be located between the first wall 21a and the pressure relief mechanism 11. Exemplarily, the first wall 21a and the pressure relief mechanism 11 are disposed along the axial direction Z, and at least a portion of the protective member 30 is located between the first wall 21a and the pressure relief mechanism 11 in the axial direction Z.

[0095] When the pressure release mechanism 11 is activated to form the pressure release hole 111, the protective member 30 can cover the pressure release hole 111 in the axial direction Z. In this embodiment, "the protective member 30 covers the pressure release hole 111 in the axial direction Z of the pressure release hole 111" means that the projection of the pressure release hole 111 in the axial direction Z is located within the projection of the protective member 30 in the axial direction Z. The area of ​​the projection of the protective member 30 in the axial direction Z may be equal to or greater than the area of ​​the projection of the pressure release hole 111 in the axial direction Z.

[0096] The protective member 30 may be a plate-like structure, a frame structure, or other structure. For example, the protective member 30 may be a flat plate having a uniform thickness, or a plate having a non-uniform thickness.

[0097] The protective member 30 may be an integral structure, or may be a structure assembled from multiple sub-members.

[0098] The protective member 30 may be fixed to the first wall 21a, may be fixed to the battery unit 10, or may be fixed to another member within the housing 20, and the embodiments of the present application are not limited thereto.

[0099] The thermal shock resistance of the protective member 30 is superior to that of the first wall 21a. Thermal shock resistance refers to the ability of a material to withstand a sudden change in temperature without breaking. In other words, when subjected to the same high-temperature, high-velocity material shock, the protective member 30 is less likely to break than the first wall 21a.

[0100] The portion of the protective member 30 that covers the pressure release hole 111 in the axial direction Z may be referred to as the protective portion, and a projection of the protective portion in the axial direction Z completely overlaps with a projection of the pressure release hole 111 in the axial direction Z. The protective portion is more susceptible to impacts from high-temperature, high-velocity substances than other portions of the protective member 30.

[0101] The unit of the flow rate G is liters / second (L / s). In the embodiment of the present application, the flow rate G may be an average flow rate of gas released by the battery unit 10 through the pressure relief hole 111.

[0102] The flow rate G of gas released by the battery unit 10 through the pressure relief hole 111 is V / t, where V is the amount of gas (unit: L) at room temperature and pressure (25°C, 1 atm) due to thermal runaway of the battery unit 10, and t is the time of thermal runaway of the battery unit 10.

[0103] For example, the flow rate G of the battery unit 10 is measured and obtained according to the following method.

[0104] Test sample: a battery unit 10 in a fully charged state.

[0105] Test environment: a sealed tank (no significant volume change or gas leakage occurs during the thermal runaway process of the battery unit 10), the space inside the tank is V0, and the inside of the tank is at normal temperature and pressure (25° C., 1 atm).

[0106] Test flow: The battery unit 10 is placed in a sealed tank and thermal runaway of the battery unit 10 is triggered. The pressure relief mechanism 11 of the battery unit 10 is activated and a pressure relief hole 111 is formed. The substances released by the battery unit 10 may cause temperature and pressure changes in the tank. After the battery unit 10 has been in thermal runaway for 15 minutes, the temperature in the tank is balanced. At this time, it is detected that the air pressure in the tank is P1 and the temperature at the center of the tank is T0. Based on the ideal state equation, the amount of gas caused by thermal runaway of the battery unit 10 at normal temperature and pressure (25°C, 1 atm) is:

number

[0107] In the above test flow, R is the gas constant, R=8.314J / (mol·K), and 24.5 is the molar volume of the gas at normal temperature and pressure. The method for triggering thermal runaway of the battery unit 10 can refer to GB 38031-2020 C.5.3.4. The center point of the tank may be the geometric center of the inner cavity of the tank.

[0108] The time t of thermal runaway of the battery unit 10 is the time interval from when the battery unit 10 starts experiencing thermal runaway until the air pressure inside the sealed tank reaches its maximum value.

[0109] The gas released when the battery unit 10 experiences thermal runaway acts on the protective member 30, which reduces the thermal shock received by the first wall 21a and reduces the amount of heat transferred to the first wall 21a, thereby reducing the risk of the first wall 21a melting and being penetrated, and improving the safety of the battery 2. The larger the value of D, the lower the risk of the protective member 30 being broken through by the gas, and the smaller the amount of heat transferred to the first wall 21a.

[0110] The higher the flow rate G of the gas generated when the battery unit 10 goes into thermal runaway, the greater the thermal shock of the gas that the protective member 30 receives, and the higher the demand for D of the protective member 30. Conversely, the lower the flow rate G of the gas generated when the battery unit 10 goes into thermal runaway, the smaller the thermal shock of the gas that the protective member 30 receives, and the lower the demand for D of the protective member 30. When the flow rate G is determined, it is necessary to guarantee a minimum value of D in order to reduce the risk of the protective member 30 being broken through and to reduce the amount of heat transferred to the first wall 21a. Of course, the larger the value of D, the larger the volume and weight of the protective member 30. When the flow rate G is determined, the maximum value of D may be limited to reduce the redundancy of the size design of the protective member 30 on the premise of compatibility with the thermal protection requirements, and to reduce the loss of energy density of the battery 2.

[0111] The inventor, through research, has determined that the value of D / G is 2×10 -3 mm s / L-3.3×10 -1 By limiting it to mm·s / L, the redundancy in the size design of the protective member 30 is reduced while still meeting thermal protection requirements, the loss in energy density of the battery 2 is reduced, and the safety of the battery 2 is improved.

[0112] In some embodiments, the value of D / G is 2×10 -3 mm s / L, 5×10 -3 mm s / L, 1×10 -2 mm s / L, 5×10 -2 mm s / L, 1×10 -1 mm s / L, 2×10 -1 mm s / L, 3×10 -1 mm s / L or 3.3×10-1 mm·s / L.

[0113] In some embodiments, the protective member 30 can play a role of insulation to reduce the amount of heat transferred to the first wall 21a. When the battery unit 10 experiences thermal runaway, the amount of heat transferred to the first wall 21a is relatively small due to the presence of the protective member 30, so that the embodiments of the present application can reduce the requirements for the material of the housing 20.

[0114] For example, the housing 20 may use some materials that cannot withstand high temperatures, such as polyester materials. Of course, the housing 20 may use some materials that are relatively resistant to high temperatures, such as aluminum, steel or other metals. When the housing 20 uses a material that is relatively resistant to high temperatures, the value of D / G may be adaptively reduced, thereby reducing the space and weight occupied by the protective member 30 and improving the energy density of the battery 2.

[0115] In some embodiments, D and G are 2×10 -3 mm s / L≦D / G≦2×10 -1 Meets mm s / L.

[0116] In some embodiments, the value of D is between 0.5 mm and 5 mm. Optionally, the value of D is 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm.

[0117] The smaller the value of D, the higher the risk that the protective member 30 will be broken through by the gas, and the larger the value of D, the lower the risk that the protective member 30 will be broken through by the gas and the greater the space and weight that the protective member 30 will occupy within the battery 2. By limiting the value of D to 0.5 mm to 5 mm, the inventors reduce the redundancy in the size design of the protective member 30 while still meeting thermal protection requirements, reduce the loss of energy density of the battery 2, reduce the difficulty of molding the protective member 30, and improve the safety of the battery 2.

[0118] In some embodiments, the protective member 30 has thermal insulation properties, and its thermal conductivity is smaller than that of the first wall 21a. The protective member 30 can play a role of heat insulation to reduce the amount of heat conducted to the first wall 21a when the battery unit 10 experiences thermal runaway. In other alternative embodiments, the protective member 30 may have relatively good thermal conductivity, and the protective member 30 can quickly conduct the amount of heat to the surroundings, reduce the concentration of the amount of heat, and reduce the temperature of the first wall 21a.

[0119] In some embodiments, the material of armor member 30 includes at least one of an inorganic salt, an inorganic ceramic, an elemental metal, an elemental carbon, and an organic colloid.

[0120] In some examples, the inorganic salt comprises a silicate.

[0121] In some examples, the inorganic ceramic includes at least one of alumina, silica, boron carbide, boron nitride, silicon carbide, silicon nitride, and zirconia.

[0122] In some examples, the metal-based material includes at least one of copper, iron, aluminum, tungsten, and titanium.

[0123] In some examples, the elemental carbon includes at least one of amorphous carbon and graphite.

[0124] In some examples, the organic colloid comprises at least one of an epoxy resin structural adhesive, an acrylate structural adhesive, a polyimide structural adhesive, a maleimide structural adhesive, a polyurethane structural adhesive, and an acrylic structural adhesive.

[0125] In some embodiments, the material of armor member 30 includes at least two of an inorganic salt, an inorganic ceramic, an elemental metal, an elemental carbon, and an organic colloid.

[0126] A composite structure formed from multiple materials can improve the thermal shock resistance and thermal insulation capabilities of the armor member 30.

[0127] In some embodiments, armor 30 includes carbon fiber plates formed from carbon fiber cloth and organic colloids.

[0128] In some embodiments, guard member 30 includes a resin sheet formed from inorganic ceramic powders and organic colloids.

[0129] In some embodiments, armor 30 includes a graphite layer and a metal layer disposed in a stacked fashion.

[0130] In some embodiments, armor 30 includes composite fiber sheets made of carbon and ceramic fibers.

[0131] In some embodiments, armor 30 includes a ceramic layer and a metal mesh connected to the ceramic layer.

[0132] In some embodiments, the melting point of the protective member 30 is greater than 1000° C. With a relatively high melting point, the protective member 30 is less likely to melt when subjected to thermal shock, so that the protective member 30 has relatively good thermal shock resistance performance and reduces the risk of the protective member 30 being pierced.

[0133] In some embodiments, the melting point of armor 30 is greater than 1500°C.

[0134] In some embodiments, the melting point of the protective member 30 is higher than that of the first wall 21a, so that the protective member 30 has better thermal shock resistance performance with respect to the first wall 21a, thereby fulfilling the thermal protection function and reducing the risk of the first wall 21a being damaged.

[0135] In some embodiments, the protective member 30 is fixed to the first wall 21a. The first wall 21a can fix the protective member 30, thereby reducing the risk of the protective member 30 moving around due to the impact of high-temperature, high-velocity gas, reducing the probability of the protective member 30 being damaged by collision, and reducing the risk of the protective member 30 losing its protection.

[0136] In some embodiments, the guard member 30 is secured to the first wall 21a by gluing, welding, fasteners, or locking. Of course, the guard member 30 may be secured to the first wall 21a in other ways.

[0137] In some embodiments, the guard member 30 is disposed on the inner surface of the first wall 21a.

[0138] In some embodiments, the first wall 21a is located on the upper side or the lower side of the battery unit 10. Exemplarily, the first wall 21a is located on the upper side of the battery unit 10, as shown in FIG.

[0139] In some embodiments, the volumetric energy density of the battery unit 10 is E, and D and E are 1×10 -3 mm L / Wh≦D / E≦1×10 -2 Meet mm L / Wh.

[0140] The unit of the volumetric energy density E is Wh / L, and E=C / V1, where C is the capacity of the battery unit 10 and V1 is the volume of the battery unit 10.

[0141] For illustrative purposes, the volume of the housing 12 of the battery unit 10 is taken as the volume of the battery unit 10, and the volume of the poles 14 protruding from the housing 12 of the battery unit 10 is not taken into consideration. For example, the length, width, and height of the housing 12 of a rectangular battery unit 10 are l1, l2, and l3, respectively, and V1 = l1 x l2 x l3.

[0142] Generally, when thermal runaway occurs in the battery unit 10, the higher the value of E, the more violent the chain reaction that occurs inside the battery unit 10, the higher the temperature of the gas released by the battery unit 10, and the larger the flow rate G.

[0143] The higher the volumetric energy density E of the battery unit 10, the greater the thermal shock of the gas that the protective member 30 receives, and the higher the demand for D of the protective member 30. Conversely, the lower the volumetric energy density E of the battery unit 10, the smaller the thermal shock of the gas that the protective member 30 receives, and the lower the demand for D of the protective member 30. When the volumetric energy density E is determined, it is necessary to guarantee a minimum value of D in order to reduce the risk of the protective member 30 being broken through and to reduce the amount of heat transferred to the first wall 21a. Of course, the larger the value of D, the greater the volume and weight of the protective member 30. When the volumetric energy density E is determined, the maximum value of D may be limited to reduce the redundancy of the size design of the protective member 30 on the premise of compatibility with the thermal protection requirements, and to reduce the loss of energy density of the battery 2.

[0144] The volumetric energy density E of the battery unit 10 has a positive correlation with the flow rate G, and the volumetric energy density E of the battery unit 10 is easier to determine than the flow rate G. The inventors have attempted to reduce the difficulty of designing the protective member 30 by indirectly characterizing the flow rate G with the volumetric energy density E and limiting the value of D with the volumetric energy density E through experiments and calculations.

[0145] Alternatively, the value of D / E may be 1×10 -3 mm L / Wh, 2×10 -3 mm L / Wh, 4×10 -3 mm L / Wh, 6×10 -3 mm L / Wh, 8×10 -3 mm L / Wh or 1×10 -2 mm L / Wh.

[0146] In some embodiments, D and E are 1×10 -3 mm L / Wh≦D / E≦6×10 -3 Meet mm L / Wh.

[0147] In some embodiments, the size of the protective member 30 is larger than the size of the pressure relief hole 111 in any direction perpendicular to the axial direction Z.

[0148] The gas released through the pressure release hole 111 mainly flows along the axial direction Z of the pressure release hole 111, and of course, some of the gas and substances such as particles carried by the gas may dissipate to the surroundings even after passing through the pressure release hole 111. In this embodiment, the protective member 30 has a relatively large size compared to the pressure release hole 111, which can effectively block the gas, reduce the risk of the gas directly colliding with the first wall 21a, and improve safety.

[0149] In some embodiments, the size of the pressure relief hole 111 in the maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111 is k, and the size of the protective member 30 along the maximum size direction X is K. k, K, and G are K>k, (K / k) / G≧3×10 -3 Meet s / L.

[0150] In a plurality of directions perpendicular to the axial direction Z, the size of the pressure release hole 111 along one of the directions is equal to or larger than the size of the pressure release hole 111 along the other direction, and this direction is called the maximum size direction X of the pressure release hole 111. The size K of the protective member 30 is the size of the protective member 30 along the maximum size direction X of the pressure release hole 111.

[0151] The higher the gas flow rate G generated when the battery unit 10 experiences thermal runaway, the greater the thermal shock to the protective member 30 caused by the gas released by the battery unit 10, which means a higher risk of the gas and other carried substances being scattered to parts of the first wall 21a that are not shielded by the protective member 30, and a higher temperature in the parts of the first wall 21a that are not shielded by the protective member 30.

[0152] The inventors limit the size relationship between the protective member 30 and the pressure relief hole 111 in the maximum size direction X based on the flow rate G of gas generation in the battery unit 10 when thermal runaway occurs, thereby keeping the temperature of the portion of the first wall 21a that is not shielded by the protective member 30 within a certain range, thereby reducing the risk of damage to the first wall 21a.

[0153] When the flow rate G of gas generated when the battery unit 10 experiences thermal runaway is relatively small, the protective member 30 may have a relatively small size, thus reducing the space and weight of the battery 2 occupied by the protective member 30 and improving the energy density. When the flow rate G of gas generated when the battery unit 10 experiences thermal runaway is relatively large, the protective member 30 may have a relatively large size, thus increasing the range of the first wall 21a shielded by the protective member 30 and reducing the temperature of the first wall 21a.

[0154] In some embodiments, k, K, and G are such that (K / k) / G≧8×10 -3 Meet s / L.

[0155] In some embodiments, k, K, and G satisfy (K / k) / G≦20s / L. This embodiment can reduce redundancy in the size design of the protective member 30 and reduce loss of energy density of the battery 2.

[0156] In some embodiments, the value of (K / k) / G is 3×10 -3 s / L, 5×10 -3 s / L, 8 x 10 -3 s / L, 1×10 -2 s / L, 5×10 -2 s / L, 1×10 -1 s / L, 5×10 -1 s / L, 1s / L, 5s / L, 10s / L, 15s / L, 20s / L.

[0157] In some embodiments, the minimum distance in the axial direction Z between the protective member 30 and the pressure relief hole 111 is h, and h and D satisfy 0.2≦h / D≦250.

[0158] When h is sufficiently low, the temperature and speed of the gas acting on the protective member 30 are hardly decreased, and the thermal shock experienced by the protective member 30 is relatively large, and accordingly, there is a minimum value for D to ensure the protective effect. When h is sufficiently high, the temperature and speed of the gas acting on the protective member 30 are significantly decreased, and the thermal shock experienced by the protective member 30 is relatively small, and accordingly, there is a maximum value for D, which is compatible with the thermal runaway protection requirements while being economical and reducing the redundancy of the design. The inventors have found through experiments and calculations that by limiting the value of h / D to 0.2-250, the redundancy of the size design of the protective member 30 can be reduced under the premise of being compatible with the thermal protection requirements, the loss of energy density of the battery 2 can be reduced, and the safety of the battery 2 can be improved.

[0159] In some embodiments, a plurality of battery units 10 are provided in the housing 20, and the protective member 30 is used to cover the pressure relief holes 111 of the plurality of battery units 10 in the axial direction Z. Even if thermal runaway occurs in any of the battery units 10, the protective member 30 plays a role in blocking the high-temperature, high-velocity substance, and can reduce the risk of damage to the first wall 21a.

[0160] In some embodiments, the guard member 30 has a flat plate structure, and the thickness direction of the guard member 30 is parallel to the axial direction Z. Illustratively, the guard member 30 has a thickness D.

[0161] In some embodiments, the battery includes a plurality of battery units 10 arranged in series, and illustratively, an arrangement direction Y of the plurality of battery units 10 is perpendicular to the axial direction Z and the maximum size direction X.

[0162] FIG. 8 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0163] 8, in some embodiments, the thickness of the protective member 30 gradually decreases from the middle to both sides in the maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111, and the thickness direction of the protective member 30 is parallel to the axial direction Z. The thickest part of the protective member 30 covers at least a part of the pressure relief hole 111 in the axial direction Z.

[0164] The thickest part of the protective member 30 faces the pressure relief hole 111, which can withstand a relatively large thermal shock and reduce the risk of the protective member 30 being broken through. The thermal shock experienced by both ends of the protective member 30 is relatively small, and the protective member 30 can have a relatively small thickness, which reduces the weight and volume of the protective member 30 and improves the energy density of the battery 2.

[0165] In some embodiments, the protective member 30 has a slope on one side facing the pressure relief hole 111, and the slope can guide the gas flow and reduce the thermal shock that the protective member 30 receives. FIG. 9 is a structural schematic diagram of a battery according to some other embodiments of the present application, and FIG. 10 is an enlarged schematic diagram of block B in FIG.

[0166] 9 and 10, in some embodiments, the protective member 30 includes a base region 30a and a reinforcing region 30b connected to the base region 30a, and the size of the reinforcing region 30b along the axial direction Z is larger than the size of the base region 30a along the axial direction Z. In the axial direction Z, the reinforcing region 30b covers at least a portion of the pressure relief hole 111.

[0167] The reinforced area 30b faces the pressure relief hole 111, which can withstand a relatively large thermal shock and reduces the risk of the protective member 30 being broken through.

[0168] In some embodiments, the reinforcement region 30b completely covers the pressure relief hole 111 in the axial direction Z. The reinforcement region 30b can withstand a relatively large thermal shock, thereby reducing the risk of the protective member 30 being broken through. The base region 30a does not face the pressure relief hole 111 in the axial direction Z, and may have a relatively small thickness in order to reduce the weight and volume of the protective member 30 and improve the energy density of the battery 2.

[0169] In some embodiments, in the maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111, the size of the protective member 30 is K, and the size of the reinforcement region 30b is K1. K, K1, and G are K>K1, (K / K1) / G≦2×10 -1 Meet s / L.

[0170] The higher the flow rate G of the gas generated when the battery unit 10 experiences thermal runaway, the greater the thermal shock to the protective member 30 caused by the gas released by the battery unit 10, and the higher the size requirement for the reinforced region 30b of the protective member 30. -1 By limiting it to s / L or less, the reinforcement region 30b and the base region 30a block the high-temperature, high-velocity substance, reducing the amount of heat transferred to the first wall 21a and making it possible to reduce the temperature of the first wall 21a.

[0171] In some embodiments, there are two base regions 30a, and the two base regions 30a are located on both sides of the reinforcement region 30b along the maximum size direction X, respectively.

[0172] In some embodiments, the two substrate regions 30a are symmetrical with respect to an imaginary plane perpendicular to the maximum size direction X.

[0173] In some embodiments, the reinforcement region 30b and the base region 30a are both flat plate structures, and the thickness direction of the reinforcement region 30b and the thickness direction of the base region 30a are both parallel to the axial direction Z.

[0174] Exemplarily, the thickness of the reinforced region 30b is D.

[0175] In some embodiments, the size of the reinforcement region 30b along the axial direction Z is D, and the size of the base region 30a along the axial direction Z is d. In the maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111, the size of the pressure relief hole 111 is k, and the size of the reinforcement region 30b is K1. D, d, k, and K1 satisfy 0.04≦(K1 / k) / (D / d)≦300.

[0176] As the K1 / k value increases, the proportion of thermal shock that the reinforcement region 30b receives when the battery unit 10 experiences thermal runaway increases, and the thermal runaway protection requirement that the base region 30a must meet decreases, and accordingly the D / d ratio may increase, i.e., the thickness requirement for the base region 30a may decrease. As the K1 / k value decreases, the thermal runaway protection requirement that the base region 30a must meet increases, and accordingly the D / d ratio may decrease, i.e., the thickness requirement for the base region 30a increases. When K1 / k is sufficiently small, the thermal runaway protection requirement that the substrate region 30a must meet is relatively large, and there is a minimum value for D / d, i.e., there is a maximum value for d, thereby satisfying the thermal runaway protection requirement of the substrate region 30a; when K1 / k is sufficiently large, the thermal runaway protection requirement that the substrate region 30a must meet is relatively small, and there is a maximum value for D / d, i.e., there is a minimum value for d, thereby achieving compatibility with the thermal runaway protection requirement while being economical and reducing design redundancy.

[0177] By limiting the value of (K1 / k) / (D / d) to 0.04-300, the inventor reduces the redundancy in the size design of the protective member 30 while maintaining compatibility with thermal protection requirements, thereby reducing the loss of energy density of the battery 2 and improving the safety of the battery 2.

[0178] FIG. 11 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0179] As shown in FIG. 11, in some embodiments, the protective member 30 includes a first protective plate 31 and a second protective plate 32 that are stacked along the axial direction Z, and the portion where the first protective plate 31 and the second protective plate 32 overlap in the axial direction Z and the second protective plate 32 constitute a reinforcement region 30b, and the portion where the first protective plate 31 and the second protective plate 32 do not overlap in the axial direction Z constitutes a base region 30a.

[0180] The material of the first protective plate 31 and the material of the second protective plate 32 may be the same or different.

[0181] The second protective plate 32 may be installed on one side of the first protective plate 31 facing the pressure relief mechanism 11 , or on one side of the first protective plate 31 facing away from the pressure relief mechanism 11 .

[0182] The number of the second protective plates 32 may be one or more, and the embodiment of the present application is not limited thereto.

[0183] The second protective plate 32 may be a flat plate having a uniform thickness, or may be a plate having a non-uniform thickness.

[0184] The first protective plate 31 and the second protective plate 32 are laminated to form the protective member 30 having a different thickness. In this embodiment, the molding process of the protective member 30 can be simplified.

[0185] In some embodiments, the second guard plate 32 is installed on one side of the first guard plate 31 facing the pressure relief mechanism 11 .

[0186] In this embodiment, the flatness of the one side of the protective member 30 that is away from the pressure release mechanism 11 can be improved, and fixing of the protective member 30 to another member can be facilitated.

[0187] In some embodiments, the first protective plate 31 and the second protective plate 32 are both flat plate structures, and the thickness direction of the first protective plate 31 and the thickness direction of the second protective plate 32 are both parallel to the axial direction Z.

[0188] In some embodiments, the material of the second protective plate 32 is different from the material of the first protective plate 31. The first protective plate 31 and the second protective plate 32 may be made of different materials, and by combining the properties of the different materials in this way, a protective member 30 with higher thermal shock resistance performance may be compounded. Compared with the first protective plate 31 and the second protective plate 32 made of the same material, the first protective plate 31 and the second protective plate 32 made of different materials may provide a more varied structure for the protective member 30.

[0189] In some embodiments, the thermal shock resistance performance of the second guard plate 32 is superior to that of the first guard plate 31 .

[0190] In some embodiments, the melting point of the second protective plate 32 is higher than the melting point of the first protective plate 31. Exemplarily, the melting point of the second protective plate 32 is higher than 1000° C. The embodiments of the present application do not limit the melting point of the first protective plate 31, and the melting point of the first protective plate 31 may be 1000° C. or higher or 1000° C. or lower.

[0191] In some embodiments, the second guard plate 32 is glued to the first guard plate 31 .

[0192] FIG. 12 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0193] 12, in some embodiments, the first protective plate 31 has a flat plate structure, and the thickness direction of the first protective plate 31 is parallel to the axial direction Z. In the maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111, the size of the second protective plate 32 along the axial direction Z gradually decreases from the middle to both ends.

[0194] The portion of the second protective plate 32 that is largest in size along the axial direction Z may face the pressure relief hole 111, thereby reducing the risk of a relatively large thermal shock being received and breaking through the protective member 30. The thermal shock received by both ends of the second protective plate 32 is relatively small, and the second protective plate 32 can have a relatively small thickness, reducing the weight and volume of the second protective plate 32 and improving the energy density of the battery 2.

[0195] In some embodiments, the second protective plate 32 has a slope on one side facing the pressure relief hole 111, which can guide the gas flow and reduce the thermal shock experienced by the second protective plate 32.

[0196] FIG. 13 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0197] As shown in FIG. 13, in some embodiments, the second protection plates 32 are multiple, and the multiple second protection plates 32 are installed at intervals.

[0198] In some embodiments, the number of second guard plates 32 is the same as the number of reinforcement regions 30b.

[0199] In some embodiments, the second guard plate 32 is a flat plate structure.

[0200] In some embodiments, the second protection plates 32 are spaced apart in a maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111 .

[0201] FIG. 14 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0202] As shown in FIG. 14, in some embodiments, the second protection plates 32 are multiple, and the multiple second protection plates 32 are installed at intervals or continuously.

[0203] In some embodiments, the first protective plate 31 has a flat plate structure, and the thickness direction of the first protective plate 31 is parallel to the axial direction Z. In the maximum size direction X perpendicular to the axial direction Z of the pressure relief hole 111, the size of each second protective plate 32 along the axial direction Z gradually decreases from the middle to both ends.

[0204] FIG. 15 is a structural schematic diagram of a battery according to some other embodiments of the present application.

[0205] As shown in FIG. 15, in some embodiments, the first wall 21a may be disposed on the underside of the battery unit 10.

[0206] According to some embodiments of the present application, the present application further provides a power consuming device, comprising the battery of any one of the above embodiments, the battery being used to provide electrical energy to the power consuming device. The power consuming device may be any one of the above battery-based appliances or systems.

[0207] According to some embodiments of the present application, with reference to Figs. 3 to 7, the present application provides a battery 2 including a housing 20, a battery unit 10, and a protective member 30. The battery unit 10 is housed in the housing 20. The housing 20 includes a first wall 21a located on an upper side of the battery unit 10. The battery unit 10 is provided with a pressure relief mechanism 11, which forms a pressure relief hole 111 and is used to release a substance inside the battery unit 10.

[0208] The protective member 30 is housed in the housing 20 and fixed to the first wall 21a. At least a portion of the protective member 30 is located between the first wall 21a and the pressure release mechanism 11, and is used to cover the pressure release hole 111 in the axial direction Z of the pressure release hole 111. The size of the protective member 30 is larger than the size of the pressure release hole 111 in any direction perpendicular to the axial direction Z.

[0209] The minimum size along the axial direction Z of the portion of the protective member 30 that covers the pressure release hole 111 in the axial direction Z is D, the flow rate of gas released by the battery unit 10 through the pressure release hole 111 is G, and D and G are expressed as 2×10 -3 mm s / L≦D / G≦3.3×10 -1 Meets mm s / L.

[0210] The present application will be further described below in conjunction with examples.

[0211] In order to make the invention purpose, technical solution and beneficial technical effects of the present application clearer, the present application will be described in more detail below in conjunction with examples.However, it should be understood that the examples of the present application are only for interpreting the present application, and do not limit the present application, and the examples of the present application are not limited to the examples shown in the specification.In the examples, the specific experimental conditions or operation conditions are not specified, and are prepared under normal conditions or under the conditions recommended by the material supplier.

[0212] Example 1: (i) Two identical rectangular battery units are manufactured, and each battery unit has a length l1 of 220 mm, a width l2 of 44 mm, and a height l3 of 100 mm.

[0213] (ii) Test the flow rate G of gas released from one battery unit through the pressure relief hole, and G is 500 L / s.

[0214] (iii) Another battery unit is placed in a sealed housing, and a protective member is attached to a wall (hereinafter referred to as a first wall) of the housing located above the battery unit, the protective member being used to face the pressure release mechanism of the battery unit and cover the pressure release hole. The protective member is a flat plate with a thickness D of 1 mm, and is made of a composite plate made of boron nitride and carbon fiber. In the axial direction of the pressure release hole, the distance h between the protective member and the pressure release hole is 15 mm.

[0215] (iv) Triggering a thermal runaway of the battery unit inside the housing, forming a pressure relief hole in the battery unit, and releasing materials to the outside. During the process of the thermal runaway of the battery unit, measuring temperatures at multiple points on the surface of the protective member away from the battery unit, and recording the maximum temperature T1 of the surface of the protective member away from the battery unit.

[0216] (v) After the thermal runaway of the battery unit has ended, open the housing and observe whether the protective member has been broken through.

[0217] Examples 2-9: The test method of Examples 2-9 refers to Example 1, and the differences between Examples 2-9 and Example 1 are as shown in Table 1. For example, the flow rate G of the battery unit can be changed by changing the chemical system of the battery unit.

[0218] Comparative Examples 1-4: The test methods of Comparative Examples 1-4 refer to Example 1, and the differences between Comparative Examples 1-4 and Example 1 are as shown in Table 1.

[0219] [Table 1]

[0220] With reference to Examples 1-9 and Comparative Examples 1-2, the examples of the present application have a D / G value of 2×10 -3 By limiting the thermal insulation resistance to 100% or more, the risk of the protective material being broken through can be reduced and the thermal protection requirements for the battery can be met.

[0221] Referring to Examples 1-9 and Comparative Examples 3-4, the protective member can block the conduction of heat, reduce the amount of heat transferred to the housing, and reduce the temperature of the housing. When D / G becomes large to a certain extent, the temperature of the housing can meet the demand. In this embodiment, the value of D / G is 3.3×10 -1 By limiting the capacitance to mm·s / L or less, the redundancy in the size design of the protective components is reduced, the loss of energy density in the battery is minimized, and the safety of the battery is improved.

[0222] Example 10: (i) A rectangular battery unit is manufactured, and the length l1 of the battery unit is 220 mm, the width l2 is 44 mm, and the height l3 is 100 mm. The volumetric energy density E of the battery unit is 500 Wh / L.

[0223] (ii) The battery unit is placed in a sealed housing, and a protective member is attached to a first wall of the housing located above the battery unit, the protective member facing the pressure release mechanism of the battery unit and used to cover the pressure release hole. The protective member is a flat plate with a thickness D of 5 mm and made of a composite plate made of boron nitride and carbon fiber. In the axial direction of the pressure release hole, the distance h between the protective member and the pressure release hole is 15 mm.

[0224] (iii) Triggering a thermal runaway of the battery unit inside the housing, forming a pressure relief hole in the battery unit, and discharging materials to the outside. During the process of the thermal runaway of the battery unit, measuring temperatures at multiple points on the surface of the protective member away from the battery unit, and recording the maximum temperature T1 of the surface of the protective member away from the battery unit.

[0225] (iv) After the thermal runaway of the battery unit has ended, the housing is opened and it is observed whether the protective member has been broken through.

[0226] Examples 11-15: The test methods of Examples 11-15 refer to Example 10. The differences between Examples 11-15 and Example 10 are shown in Table 2. For example, the volumetric energy density E of the battery unit may be changed by changing the chemical system of the battery unit.

[0227] Comparative Example 5-8: The test method of Comparative Example 5-8 is similar to that of Example 10. The differences between Comparative Example 5-8 and Example 10 are shown in Table 2.

[0228] [Table 2]

[0229] With reference to Examples 10-15 and Comparative Examples 5-6, the examples of the present application have a D / E value of 1×10 -3 By limiting the thermal insulation capacity to 1000 MPa or more, the risk of the protective material being broken through can be reduced and the thermal protection requirements for the battery can be met.

[0230] Referring to Examples 10-15 and Comparative Examples 7-8, the protective member can block the conduction of heat, reduce the amount of heat transferred to the housing, and reduce the temperature of the housing. When D / E becomes large to a certain extent, the temperature of the housing can meet the demand. In this embodiment, the value of D / E is set to 10×10 -3 By limiting the capacity to mm L / Wh or less, the redundancy in the size design of the protective components is reduced, the loss of energy density in the battery is minimized, and the safety of the battery is improved.

[0231] Example 16: (i) Two identical rectangular battery units are manufactured, and each battery unit has a length l1 of 220 mm, a width l2 of 44 mm, and a height l3 of 100 mm.

[0232] (ii) Test the flow rate G of gas released from one battery unit through the pressure relief hole, where G is 200 L / s. The size k of the pressure relief hole in the maximum size direction perpendicular to the axial direction of the pressure relief hole is 60 mm.

[0233] (iii) Another battery unit is placed in the sealed housing, and a protective member is attached to a first wall of the housing located above the battery unit, the protective member being used to face the pressure relief mechanism of the battery unit and cover the pressure relief hole. The protective member is a flat plate with a thickness D of 2 mm and made of a composite plate made of boron nitride and carbon fiber. In the axial direction of the pressure relief hole, the distance h between the protective member and the pressure relief hole is 15 mm. In the maximum size direction of the pressure relief hole, the size K of the protective member is 180 mm.

[0234] (iv) Triggering a thermal runaway of the battery unit in the housing, causing the battery unit to form a pressure relief hole and release the substance to the outside. During the process of the thermal runaway of the battery unit, the temperature of a region of the first wall adjacent to the edge of the protective member in the maximum size direction and not covered by the protective member is measured, and the maximum temperature T2 is recorded.

[0235] (v) After the thermal runaway of the battery unit has ended, open the housing and observe whether the protective member has been broken through.

[0236] Examples 17-22: The test method of Examples 17-22 refers to Example 16. The differences between Examples 17-22 and Example 16 are shown in Table 3. For example, the flow rate G of the battery unit can be changed by changing the chemical system of the battery unit.

[0237] Comparative Examples 9-11: The test methods of Comparative Examples 9-11 refer to Example 16. The differences between Comparative Examples 9-11 and Example 16 are as shown in Table 3.

[0238] [Table 3]

[0239] With reference to Examples 16-22 and Comparative Example 9, when K=k, some of the gas released through the pressure relief hole may diffuse and act on the area of ​​the first wall not covered by the protective member, causing the temperature of the first wall to be relatively high. In the embodiments of the present application, K is preferably made larger than k, thereby increasing the protection range of the protective member, reducing the risk of gas directly colliding with the first wall, reducing the temperature of the first wall, and improving safety.

[0240] With reference to Examples 16-22 and Comparative Examples 10-11, the examples of the present application have a (K / k) / G value of 3×10 -3 By limiting it to s / L or more, the temperature of the portion of the first wall that is not shielded by the protective member is kept within a certain range, thereby reducing the risk of damage to the first wall.

[0241] Example 23: (i) Two identical rectangular battery units are manufactured, and each battery unit has a length l1 of 220 mm, a width l2 of 44 mm, and a height l3 of 100 mm.

[0242] (ii) Test the flow rate G of gas released from one battery unit through the pressure relief hole, where G is 15 L / s. The size k of the pressure relief hole in the maximum size direction perpendicular to the axial direction of the pressure relief hole is 50 mm.

[0243] (iii) Another battery unit is placed in the sealed housing, and a protective member is attached to a first wall of the housing located above the battery unit, the protective member is used to face the pressure release mechanism of the battery unit and cover the pressure release hole. The protective member has a structure with a thick center, that is, the protective member includes a reinforced region in the center and base regions on both sides, the thickness D of the reinforced region is 2 mm, and the thickness of the base region is 1 mm. The material of the protective member is a composite plate made of boron nitride and carbon fiber. In the axial direction of the pressure release hole, the reinforced region faces the pressure release hole, and the distance h between the reinforced region and the pressure release hole is 15 mm. In the maximum size direction of the pressure release hole, the size K of the protective member is 180 mm, the size K1 of the reinforced region is 60 mm, and the size of each base region is 60 mm.

[0244] (iv) Triggering a thermal runaway of the battery unit in the housing, forming a pressure relief hole in the battery unit, and discharging materials to the outside. During the process of the thermal runaway of the battery unit, measuring temperatures at multiple points on the surface of the base region away from the battery unit, and recording the maximum temperature T3 of the surface of the base region away from the battery unit.

[0245] (v) After the thermal runaway of the battery unit has ended, open the housing and observe whether the protective member has been broken through.

[0246] Examples 24-25: The test methods of Examples 24-25 refer to Example 23. The differences between Examples 24-25 and Example 23 are as shown in Table 4.

[0247] Comparative Examples 12-13: The test methods of Comparative Examples 12-13 refer to Example 23. The differences between Comparative Examples 12-13 and Example 23 are as shown in Table 4.

[0248] [Table 4]

[0249] With reference to Examples 24-25 and Comparative Examples 12-13, the examples of the present application have a (K / K1) / G value of 2×10 -1 By limiting the thickness to s / L or less, the reinforcement region and the base region can block the high-temperature, high-velocity material, thereby reducing the amount of heat transferred to the first wall and decreasing the temperature of the first wall.

[0250] It should be mentioned that, unless there is a conflict, the embodiments and features in the embodiments in the present application may be combined with each other.

[0251] Finally, it should be explained that the above embodiments are only for explaining the technical solutions of the present application, and are not intended to limit the same. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some of the technical features thereof may be replaced with equivalents, but these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery, a housing including a first wall; a battery unit accommodated in the housing, the battery unit being provided with a pressure relief mechanism, the pressure relief mechanism forming a pressure relief hole and being used to release a substance inside the battery unit; a protective member accommodated in the housing, at least a portion of the protective member being located between the first wall and the pressure release mechanism and being used to cover the pressure release hole in an axial direction of the pressure release hole; Here, the minimum size along the axial direction of the portion of the protective member that covers the pressure release hole is D, the flow rate of gas released by the battery unit through the pressure release hole is G, and D and G are 2 x 10 －３ mm・s / L≦D / G≦3.3×10 －１ and a protective member satisfying mm·s / L.

2. D and G are 2 x 10 －３ mm・s / L≦D / G≦2×10 －１ The battery according to claim 1 , which satisfies mm·s / L.

3. The battery according to claim 1 or 2, wherein the value of D is from 0.5 mm to 5 mm.

4. The battery according to claim 1 , wherein the size of the protection member is larger than the size of the pressure relief hole in any direction perpendicular to the axial direction.

5. The volumetric energy density of the battery unit is E, and D and E are 1x10 －３ mm・L / Wh≦D / E≦1×10 －２ The battery according to claim 1 , which satisfies mm·L / Wh.

6. D and E are 1x10 －３ mm・L / Wh≦D / E≦6×10 －３ The battery according to claim 5 , which satisfies mm·L / Wh.

7. In a maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the pressure relief hole is k, and the size of the protective member along the maximum size direction is K, and k, K, and G are K>k, (K / k) / G≧3×10 －３ The battery according to claim 1 , which satisfies s / L.

8. k, K and G are (K / k) / G≧8×10 －３ 8. The battery of claim 7, wherein said battery satisfies:

9. k, K and G are The battery according to claim 7 or 8, wherein (K / k) / G≦20s / L.

10. The minimum distance in the axial direction between the protective member and the pressure relief hole is h, and h and D are The battery according to claim 1 , wherein 0.2≦h / D≦250 is satisfied.

11. The battery according to claim 1 , wherein the protective member has a flat plate structure, and a thickness direction of the protective member is parallel to the axial direction.

12. In a maximum size direction perpendicular to the axial direction of the pressure relief hole, the thickness of the protective member gradually decreases from the middle to both sides, and the thickness direction of the protective member is parallel to the axial direction; The battery according to claim 1 , wherein the thickest portion of the protective member covers at least a portion of the pressure release hole in the axial direction.

13. The protective member includes a base region and a reinforcing region connected to the base region, the reinforcing region having a size along the axial direction that is greater than a size along the axial direction of the base region, The battery according to claim 1 , wherein the reinforcing region covers at least a portion of the pressure relief hole in the axial direction.

14. The battery of claim 13 , wherein the reinforced region completely covers the pressure relief hole in the axial direction.

15. In the maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the protective member is K, and the size of the reinforcement region is K １ and K.K. １ and G is K>K １ , (K / K １ ) / G≦2×10 －１ 15. The battery of claim 14, wherein said battery meets s / L.

16. The battery according to claim 14 or 15, wherein the reinforcing region and the base region both have a flat plate structure, and a thickness direction of the reinforcing region and a thickness direction of the base region are both parallel to the axial direction.

17. The size of the reinforcement region along the axial direction is D, and the size of the base region along the axial direction is d, In a maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the pressure relief hole is k, and the size of the reinforcement region is K １ and D, d, k and K １ is 0.04≦(K １ 17. The battery according to claim 16, wherein: (D / d) / (k)≦300.

18. 18. The battery described in any one of claims 13 to 17, wherein the protective member includes a first protective plate and a second protective plate that are stacked and installed along the axial direction, and a portion where the first protective plate and the second protective plate overlap in the axial direction and the second protective plate constitute the reinforcement region, and a portion where the first protective plate and the second protective plate do not overlap in the axial direction constitutes the base region.

19. The battery of claim 18 , wherein the second guard plate is installed on one side of the first guard plate facing a pressure relief mechanism.

20. The battery according to claim 18 or 19, wherein the second protection plates are multiple, and the multiple second protection plates are installed at intervals.

21. The battery of claim 20 , wherein a plurality of the second protective plates are spaced apart in a maximum size direction perpendicular to the axial direction of the pressure relief hole.

22. The battery described in any one of claims 18 to 21, wherein the first protective plate and the second protective plate both have a flat plate structure, and the thickness direction of the first protective plate and the thickness direction of the second protective plate are both parallel to the axial direction.

23. The first protective plate has a flat plate structure, and a thickness direction of the first protective plate is parallel to the axial direction, The battery according to any one of claims 18 to 21, wherein in a maximum size direction perpendicular to the axial direction of the pressure relief hole, the size of the second protective plate along the axial direction gradually decreases from the middle to both ends.

24. 24. The battery of claim 18, wherein the material of the second protective plate is different from the material of the first protective plate.

25. 25. The battery of claim 1, wherein the first wall is located on the upper or lower side of the battery unit.

26. 26. The battery of claim 1, wherein the protective member has a melting point greater than 1000°C.

27. 27. The battery of claim 1, wherein the protective member has a melting point greater than a melting point of the first wall.

28. 28. The battery of claim 1, wherein the protective member is secured to the first wall.

29. 30. The battery of claim 28, wherein the protective member is secured to the first wall by adhesive, welding, fastener connection, or locking.

30. 30. An electrical power consuming device comprising a battery for providing electrical energy according to any one of claims 1 to 29.

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