CN221632727U - Battery module, battery and power utilization device - Google Patents

Abstract

The application discloses a battery module, a battery and an electricity utilization device, wherein the battery module comprises: the battery monomers that a plurality of stacks set up, battery monomers include the shell and establish the electrode assembly in the shell, the shell has and is located the first wall and the second wall in the battery module outside, the clearance between electrode assembly and the first wall is greater than the clearance between electrode assembly and the second wall, a plurality of battery monomers include first monomer and second monomer, the second monomer is one or more and forms monomer group, first monomer is established at monomer group's relative both ends, be equipped with pressure release portion on first free first wall and the free second wall of second. The battery module adopting the structure can reduce the damage probability of the pressure release parts on the first monomer and the second monomer, and further can improve the reliability of the battery monomer and the battery module.

Description

Battery module, battery and power utilization device

Technical Field

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

Background

In recent years, new energy automobiles have been developed dramatically, and in the field of electric automobiles, a power battery plays an important role as a power source of the electric automobile. The battery is composed of a box body and a plurality of battery monomers accommodated in the box body. The battery is used as a core part of the new energy automobile, and has high requirements on safety and service life. The battery cell in the battery can generate a large amount of heat in the continuous charge and discharge use process, and a pressure relief part can be arranged in the battery cell in the related technology, so that the pressure is relieved through the pressure relief part when the battery cell is in thermal runaway.

However, for a general battery cell, there is a problem that the reliability of the pressure release portion is poor, and thus the reliability of a battery module formed by a plurality of battery cells is poor, so how to improve the reliability of the battery module is a technical problem to be solved in the battery technology.

Disclosure of utility model

The embodiment of the application provides a battery module, a battery and an electricity utilization device, which can effectively improve the reliability of the battery module.

In a first aspect, an embodiment of the present application provides a battery module, including: the battery monomers that a plurality of stacks set up, battery monomers include the shell and establish the electrode assembly in the shell, the shell has and is located the first wall and the second wall in the battery module outside, the clearance between electrode assembly and the first wall is greater than the clearance between electrode assembly and the second wall, a plurality of battery monomers include first monomer and second monomer, the second monomer is one or more and forms monomer group, first monomer is established at monomer group's relative both ends, be equipped with pressure release portion on first free first wall and the free second wall of second.

In the above technical scheme, the monomer group that the second monomer formed is located the middle part position of battery module, and first monomer is located the outside position of battery module, because the first monomer of outside position can act on the second monomer of middle part position to play the free effect of constraint second, consequently the shell is difficult for taking place to warp under the constraint effect when the electrode assembly inflation deformation in the second monomer, and the pressure release portion is just also less on the free second wall of second the pulling effect that receives, and the probability of taking place the damage also reduces. When the electrode assembly in the first single body expands and deforms, the pressure release part is arranged on the first wall of the first single body, and the first wall is far away from the electrode assembly, so that the deformation transmission path between the electrode assembly and the first wall can be prolonged, the influence of deformation on the first wall is weakened, and the damage probability of the pressure release part on the first wall can be reduced. Therefore, the battery module adopting the structure can reduce the damage probability of the pressure release part on the first monomer and the second monomer, and further can improve the reliability of the battery monomer and the battery module.

In some embodiments of the application, the first monomer is provided in a plurality at opposite ends of the monomer group.

In the above technical solution, since the first single body is located at two opposite ends of the single body group, the deformation of the first wall of the first single body can be smaller than that of the second wall and the other walls, so that the probability of damage caused by pulling the pressure release part on the first wall is smaller. The two opposite ends of the single unit group are provided with a plurality of first single units, two sides, close to the inner side, of the plurality of first single units can be subjected to binding action, and compared with the pressure release part arranged on the second wall, the pressure release part is arranged on the first wall, so that the damage probability of the pressure release part in the battery module is reduced, and the overall reliability of the battery module is further improved.

In some embodiments of the application, the gap between the electrode assembly and the first wall is h1, wherein 4 mm.ltoreq.h1.ltoreq.10 mm. In the above technical scheme, through setting the clearance h1 between the electrode assembly and the first wall in the range of 4 mm-10 mm, the clearance h1 between the electrode assembly and the first wall can be more suitable, the degree that the first wall produced the deformation when the electrode assembly is expanded and deformed is less, the damaged probability of pressure release portion is less, simultaneously also make the volume of electrode assembly in the shell occupy more greatly, can make the battery monomer have better battery energy density.

In some embodiments of the application, the gap between the electrode assembly and the second wall is h2, wherein 0 < h 2.ltoreq.2 mm. In the above technical scheme, through setting the clearance h2 between the electrode assembly and the second wall in the range of 0-2 mm, on the one hand, a certain distance is arranged between the electrode assembly and the second wall, and when the electrode assembly expands and deforms, the time for transmitting to the second wall is prolonged, so that the deformation degree of the second wall is reduced, the damage probability of the pressure relief part is reduced, and on the other hand, the battery cell has better battery energy density.

In some embodiments of the application, the housing comprises a shell with an opening and an end cap, the end cap being closed to the opening, wherein the first wall is formed in the end cap and the second wall is formed in the shell.

In the above technical scheme, casing and end cover are components of a whole that can function independently setting, and first wall sets up on the end cover, and when electrode assembly takes place to warp, the casing takes place to warp at first, then transmits to the end cover again, because end cover and casing are two parts, the effort can produce the loss in the position that meets of casing and end cover when the transmission, and then can reduce the atress on the end cover, reduce the deflection of end cover or reduce the probability that the end cover takes place to warp, and then reduce the deflection of first wall or reduce the probability that first wall takes place to warp, reduce the probability that pressure release portion takes place to damage on the first wall.

In some embodiments of the application, the thickness of the end cap is greater than the wall thickness of the second wall.

In this technical scheme, because the thickness of end cover is greater than the wall thickness of second wall, consequently the intensity of end cover is greater than the intensity of second wall, pressure release portion establishes on first wall and already can reduce the probability that pressure release portion damaged to a certain extent, on this basis, through making the thickness of end cover be greater than the thickness of second wall, the intensity ratio of end cover is higher, the degree of first wall deformation further reduces or the probability that takes place to warp reduces, consequently the pulling force that first wall can produce further reduces, can further reduce the probability that pressure release portion damaged takes place.

In some embodiments of the application, the end cap has a thickness t1 and the second wall has a wall thickness t2, wherein 1.5mm < t 1.ltoreq.3mm and 0.8 mm.ltoreq.t2.ltoreq.1.5 mm.

In the technical scheme, the thickness t1 of the end cover is set in the range of 1.5-3 mm, so that the strength, the material cost and the volume ratio of the end cover in the battery monomer can be comprehensively considered, on one hand, the strength, the material cost and the volume ratio of the end cover in the battery monomer are controlled in a more reasonable range, and on the other hand, the reliability of the pressure relief part can be improved. By setting the thickness t2 of the second wall within the range of 0.8mm to 1.5mm, the strength, manufacturability, material cost and volume ratio of the second wall in the battery cell can be comprehensively considered, so that the strength, manufacturability, material cost and volume ratio of the second wall in the battery cell are controlled within a relatively reasonable range, and the reliability of the pressure relief part can be improved.

In some embodiments of the application, the first wall is provided with an electrode terminal, the electrode assembly is provided with a tab portion, and the tab portion is electrically connected to the electrode terminal.

In the above technical scheme, the clearance between the first wall and the electrode assembly can play the effect of weakening the deformation influence of the electrode assembly on the first wall on the one hand, and on the other hand can play the effect of providing the space required by bending the tab part, through integrating two functions in one place, the internal structure of the battery cell is compact, and the energy density of the battery cell can be improved.

In some embodiments of the application, the pressure relief portion is disposed away from a center of the corresponding first wall and/or the pressure relief portion is disposed away from a center of the corresponding second wall.

In the above technical scheme, when the shell is deformed and causes the deformation of the first wall, the central position of the first wall begins to deform first, and then the periphery of the first wall deforms, that is, the central position of the first wall is the deformation starting position and the deformation degree is larger than that of the periphery, so that the pressure release part is far away from the center of the corresponding first wall, the deformation of the position where the pressure release part is located is relatively smaller, the pulling force applied to the pressure release part is smaller, and the damage probability of the pressure release part is reduced. Similarly, when the shell deforms and causes the second wall to deform, the central position of the second wall begins to deform first, and then the periphery of the second wall deforms, that is to say, the central position of the second wall is the deformation starting position and the deformation degree is larger than that of the periphery, so that the pressure release part is far away from the center of the corresponding second wall, the deformation of the position where the pressure release part is located is relatively smaller, the pulling force received by the pressure release part is smaller, and the damage probability of the pressure release part is reduced.

In some embodiments of the application, the first wall and the second wall are disposed opposite or adjacent.

In the above technical scheme, the first wall and the second wall may be two opposite shell walls on the shell, that is to say, the pressure release portions on the first monomer and the second monomer are relatively arranged, when one of the first monomer or the second monomer is subject to thermal runaway, the pressure release portion of one has less influence on the pressure release portion of the other when the pressure release portion of the first monomer or the second monomer is subject to pressure release, and the reliability of the battery monomer which is not subject to thermal runaway can be improved. The first wall and the second wall can also be two adjacent shell walls on the shell, that is to say that the pressure release parts on the first monomer and the second monomer are adjacent to be arranged, and when a plurality of battery monomers are assembled, the first monomer and the second monomer are assembled easily to be distinguished, so that the occurrence of the condition of reverse assembly or wrong assembly can be reduced, and the assembly efficiency is improved.

In some embodiments of the application, the first wall is a top wall of the housing and the second wall is a bottom wall of the housing.

In the above technical scheme, the battery module is applied in the power utilization device, the battery module is generally arranged at the bottom of the power utilization device and is provided with power utilization components or personnel, when the battery module is out of control, the first monomer at the outer side can exhaust upwards and release pressure, the second monomer at the middle part can exhaust downwards and release pressure, and therefore the fire condition of the area above the battery module can be relieved, especially under the condition that the number of the second monomers is more, the loss of the power utilization components is reduced, and the injury of personnel is reduced.

In a second aspect, an embodiment of the present application further provides a battery, including the foregoing battery module.

In the above technical scheme, because the influence of battery monomer deformation is less in the pressure release portion in the battery module, consequently the probability that pressure release portion damaged takes place is lower, can promote battery module's performance and reliability, and then make the reliability of the battery that possesses battery module obtain promoting, be favorable to prolonging the life of battery, promote the performance of battery.

In a third aspect, an embodiment of the present application further provides an electrical device, including the foregoing battery module, or the foregoing battery.

In the technical scheme, the battery module or the battery is used as a key component in the power utilization device, the pressure relief part in the battery module or the battery is less influenced by the deformation of the battery monomer, and the damage probability of the pressure relief part is lower, so that the reliability of the battery module or the battery is better, and the reliability and the safety of the whole power utilization device can be improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

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

fig. 2 is an exploded view of a battery according to some embodiments of the present application;

fig. 3 is a schematic perspective view of a battery module according to some embodiments of the present application;

FIG. 4 is a schematic diagram illustrating an internal structure of a first monomer according to some embodiments of the present application;

FIG. 5 is a schematic perspective view of a first monomer according to some embodiments of the present application;

FIG. 6 is a schematic perspective view of a second monomer according to some embodiments of the present application;

fig. 7 is a side view of a battery module according to some embodiments of the present application.

Icon: 1000. a vehicle; 100. a battery; 1. a case; 11. a first tank body; 12. a second tank body; 10. a battery module; 2. a battery cell; 21. a housing; 21a, pressure relief holes; 211. a first wall; 212. a second wall; 213. an electrode terminal; 22. an electrode assembly; 221. an anode pole piece; 222. a cathode pole piece; 201. a first monomer; 202. a second monomer; 3. a pressure relief portion; 4. a heat insulating member; 5. an end plate; 200. a controller; 300. a motor; x, a first direction; y, second direction; z, third direction.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

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

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

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

The term "and/or" in the present application is merely an association relation describing the association object, and indicates that three kinds of relations may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In the present application, the character "/" generally indicates that the front and rear related objects are an or relationship.

In the embodiments of the present application, the same reference numerals denote the same components, and detailed descriptions of the same components are omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width, etc. dimensions of the various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length, width, etc. dimensions of the integrated device, are merely illustrative and should not be construed as limiting the application in any way.

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

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

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

The battery cell includes a case, an electrode assembly, and an electrolyte, and the case is used to accommodate the electrode assembly and the electrolyte. The electrode assembly consists of a positive electrode plate, a negative electrode plate and a separation film. The battery cell mainly relies on metal ions to move between the positive pole piece and the negative pole piece to work. The positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, the positive electrode current collector without the positive electrode active material layer protrudes out of the positive electrode current collector coated with the positive electrode active material layer, and the positive electrode current collector without the positive electrode active material layer is used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is coated on the surface of the negative electrode current collector, the negative electrode current collector without the negative electrode active material layer protrudes out of the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector without the negative electrode active material layer is used as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the high current is passed without fusing, the number of positive electrode lugs is multiple and stacked together, and the number of negative electrode lugs is multiple and stacked together.

The material of the separator may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may be a roll-to-roll structure or a lamination structure, and embodiments of the present application are not limited thereto.

In recent years, new energy automobiles have been developed dramatically, and in the field of electric automobiles, a power battery plays an important role as a power source of the electric automobile. The battery is composed of a box body and a plurality of battery monomers accommodated in the box body. The battery is used as a core part of a new energy automobile, and has high requirements on safety and cycle service life.

In a typical power battery, a plurality of battery cells are stacked in an arrangement to form a battery module, and then one or more battery modules are placed in a case of the battery in order to obtain sufficient power from the battery. The battery monomer in the battery module can produce a large amount of heat in the continuous charge and discharge spare use, can set up pressure release portion on the battery monomer in the correlation technique, and pressure release portion pressure release is passed through when the battery monomer takes place thermal runaway. In designing the battery cell, the space of the electrode assembly of the battery cell in the housing is as large as possible in consideration of the battery energy density, so that the electrode assembly is relatively close to the housing wall where the pressure relief part is located. After the battery monomer is used for a long time, the electrode assembly can expand and deform to extrude the shell, so that the shell is easy to bulge, the shell wall where the pressure relief part is located is easy to be pulled, after the pulling effect reaches a certain degree, the damage probability of the pressure relief part is increased, the conditions such as cracking and the like are easy to occur, the reliability of the battery monomer is reduced, and the reliability of the battery module and the battery is reduced.

Based on the above-mentioned consideration, in order to solve the problem that the reliability of the battery cell, the battery module and the battery is lowered due to the increase of the damage probability of the pressure release portion caused by the deformation of the battery cell, the inventors have devised a battery module comprising: the battery monomers that a plurality of stacks set up, battery monomers include the shell and establish the electrode assembly in the shell, the shell has first wall and the second wall that is located the battery module outside, distance between electrode assembly and the first wall is greater than distance between electrode assembly and the second wall, a plurality of battery monomers include first monomer and second monomer, the second monomer is one or more and forms monomer group, first monomer is established at monomer group's relative both ends, be equipped with pressure release portion on first free first wall and the free second wall of second.

In the battery module with the structure, the single unit group formed by the second single unit is positioned at the middle position of the battery module, the first single unit is positioned at the outer side of the battery module, and the first single unit at the outer side can act on the second single unit at the middle position and plays a role in binding the second single unit, so that the shell is not easy to deform under the binding effect when the electrode assembly in the second single unit expands and deforms, the pulling effect of the pressure release part on the second wall of the second single unit is smaller, the damage probability is reduced, and when the electrode assembly in the first single unit expands and deforms, the pressure release part is arranged on the first wall of the first single unit and the first wall is far away from the electrode assembly, thereby prolonging the deformation transmission path between the electrode assembly and the first wall, weakening the influence of deformation on the first wall and further reducing the damage probability of the pressure release part on the first wall. Therefore, the battery module adopting the structure can reduce the damage probability of the pressure release part on the first monomer and the second monomer, and further can improve the reliability of the battery monomer and the battery module.

The battery module disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the electric devices. The power supply system with the battery module, the battery and the like which are disclosed by the application can be used for forming the power utilization device, so that the application range of the battery module is favorably improved.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft and the like. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

For convenience of description, the following embodiment will take an electric device according to an embodiment of the present application as an example of the vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the application. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the interior of the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operating power source of the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

In some embodiments of the present application, battery 100 may not only serve as an operating power source for vehicle 1000, but may also serve as a driving power source for vehicle 1000, instead of or in part instead of fuel oil or natural gas, to provide driving power for vehicle 1000.

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a case 1 and a plurality of battery cells 2, and the battery cells 2 are accommodated in the case 1. Wherein, the box 1 is used for providing assembly space for the battery unit 2, and the box 1 can adopt various structures. In some embodiments, the case 1 may include a first case body 11 and a second case body 12, the first case body 11 and the second case body 12 being covered with each other, the first case body 11 and the second case body 12 together defining an assembly space for accommodating the battery cell 2. The second box body 12 may have a hollow structure with one end opened, the first box body 11 may have a plate-shaped structure, and the first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 define an assembly space together; the first tank body 11 and the second tank body 12 may each have a hollow structure with one side opened, and the open side of the first tank body 11 may be closed to the open side of the second tank body 12. Of course, the case 1 formed by the first case body 11 and the second case body 12 may be various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 100, the plurality of battery cells 2 may be connected in series or parallel or a series-parallel connection, wherein a series-parallel connection refers to that the plurality of battery cells 2 are connected in series or parallel. The plurality of battery cells 2 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 2 is accommodated in the box body 1; of course, the battery 100 may also be a battery module form formed by connecting a plurality of battery cells 2 in series or parallel or series-parallel connection, and then connecting a plurality of battery modules in series or parallel or series-parallel connection to form a whole and be accommodated in the case 1. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for making electrical connection between the plurality of battery cells 2.

The battery 100 provided in some embodiments of the present application may include a plurality of rows of battery cells 2, the plurality of rows of battery cells 2 may be arranged along the length direction of the case 1, and each row of battery cells 2 may include a plurality of battery cells 2 arranged along the width direction of the case 1. The plurality of rows of battery cells 2 may also be arranged along the width direction of the case 1, and each row of battery cells 2 may include a plurality of battery cells 2 arranged along the length direction of the case 1. Wherein each battery cell 2 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries. The battery cell 2 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped, or other shapes, etc. The battery cell 2 is illustratively cylindrical in shape.

According to some embodiments of the present application, referring to fig. 3 to 7, in a first aspect, as shown in fig. 3 and 7, an embodiment of the present application provides a battery module 10 including a plurality of battery cells 2 stacked, the battery cells 2 including a case 21 and an electrode assembly 22 disposed in the case 21, the case 21 having a first wall 211 and a second wall 212 located outside the battery module 10, a gap between the electrode assembly 22 and the first wall 211 being greater than a gap between the electrode assembly 22 and the second wall 212, the plurality of battery cells 2 including a first cell 201 and a second cell 202, the second cell 202 being one or more and forming a cell group, the first cell 201 being disposed at opposite ends of the cell group, and pressure releasing portions 3 being disposed on the first wall 211 of the first cell 201 and the second wall 212 of the second cell 202.

Referring to fig. 3 and 4, the first wall 211 may be a case wall of one side of the first direction X, the second direction Y, and the third direction Z of the case 21, and the second wall 212 may be a case wall of the other side of the first direction X, the second direction Y, and the third direction Z of the case 21. Illustratively, referring to fig. 4, the first wall 211 and the second wall 212 may be case walls at both ends of the case 21 in the third direction Z.

The electrode assembly 22 includes an anode pole piece 221 and a cathode pole piece 222, where the anode pole piece 221 and the cathode pole piece 222 may be multiple, and the multiple anode pole pieces 221 and the multiple cathode pole pieces 222 may be sequentially staggered.

Referring to fig. 3 and 7, a portion of the plurality of battery cells 2 may be referred to as a first cell 201, another portion may be referred to as a second cell 202, and the second cell 202 may be one, in which case opposite ends of the second cell 202 are provided with the first cell 201; the number of the second monomers 202 may be plural, and the plural second monomers 202 may be stacked to form a monomer group, and the first monomers 201 are disposed at opposite ends of the monomer group. That is, in the battery module 10 of the present application, the second cell 202 is disposed at the middle position and the first cell 201 is disposed at the outer position.

In the battery module 10 having the above-described structure, when the second unit 202 is one, the first units 201 at the opposite ends of the second unit 202 can bind the second unit 202, and can effectively inhibit the deformation of the case 21 of the second unit 202; referring to fig. 3 to 7, when the second monomers 202 are plural and form a monomer group, the second monomers 202 in the middle of the monomer group are bound by the second monomers 202 on the adjacent two sides, and the second monomers 202 outside the monomer group are bound by the second monomers 202 and the first monomers 201 adjacent to each other, so that deformation of the housing 21 of the second monomers 202 can be suppressed. That is, the opposite ends of each second unit 202 can be restrained, so that the deformation of the housing 21 of the second unit 202 is smaller, and thus the pulling force formed on the second wall 212 of the pressure release portion 3 of the second unit 202 is smaller, and the damage probability of the pressure release portion 3 of the second unit 202 is greatly reduced.

Referring to fig. 3, for the first unit 201, since the first unit 201 is located at the outer side of the battery module 10, after the electrode assemblies 22 of the plurality of battery units 2 are expanded and deformed, the deformation amount of the case 21 of the first unit 201 is finally larger, but since the gap between the electrode assemblies 22 and the first wall 211 is larger than the gap between the electrode assemblies 22 and the second wall 212, when the case 21 is greatly deformed, the distance between the first wall 211 and the electrode assemblies 22 is longer, the rest of the wall parts in the case 21 of the first unit 201 are deformed before the first wall 211, that is, the deformation time of the first wall 211 is later, the extrusion force caused by the expansion of the electrode assemblies 22 is gradually weakened, and the deformation that can be generated by the first wall 211 is smaller, so that the possibility that the pressure relief part 3 is damaged on the first wall 211 can be reduced, and the reliability of the first unit 201 can be improved.

In the above technical solution, the unit group formed by the second unit 202 is located at the middle position of the battery module 10, the first unit 201 is located at the outer position of the battery module 10, and since the first unit 201 at the outer position can act on the second unit 202 at the middle position and plays a role in binding the second unit 202, when the electrode assembly 22 in the second unit 202 expands and deforms, the casing 21 is not easy to deform under the binding action, the pulling action of the pressure release part 3 on the second wall 212 of the second unit 202 is small, and the probability of damage is reduced. When the electrode assembly 22 in the first unit 201 expands and deforms, the pressure release portion 3 is disposed on the first wall 211 of the first unit 201, and the first wall 211 is relatively far from the electrode assembly 22, so that the deformation transmission path between the electrode assembly 22 and the first wall 211 can be prolonged, the influence of deformation on the first wall 211 is weakened, and the damage probability of the pressure release portion 3 on the first wall 211 can be reduced. Therefore, the battery module 10 adopting the above structure can reduce the damage probability of the pressure release portion 3 on the first cell 201 and the second cell 202, and further improve the reliability of the battery cell 2 and the battery module 10.

In some embodiments of the present application, the first cells 201 are provided in plurality at opposite ends of the cell group. For example, the first cell 201 may be provided with two, three, etc. at opposite ends of the cell group.

In the above technical solution, since the first units 201 are located at opposite ends of the unit group, the deformation of the first wall 211 of the first unit 201 can be smaller than that of the second wall 212 and other walls, so that the probability of damage caused by pulling the pressure release portion 3 on the first wall 211 is smaller. The two opposite ends of the single unit group are provided with the plurality of first single units 201, two sides, close to the inner side, of the plurality of first single units 201 can be similarly subjected to the constraint effect, and compared with the second wall 212, the pressure release part 3 arranged on the first wall 211 is less in damage probability when the battery module 10 is integrally seen, so that the number of damaged pressure release parts 3 in the battery module 10 can be reduced, and the integral reliability of the battery module 10 is further improved.

In some embodiments of the present application, as shown in FIG. 4, the gap between the electrode assembly 22 and the first wall 211 is h1, wherein 4 mm.ltoreq.h1.ltoreq.10mm. The gap h1 between the electrode assembly 22 and the first wall 211 may be, but is not limited to, any one of 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm.

If the gap h1 between the electrode assembly 22 and the first wall 211 is smaller than 4mm, the gap h1 between the electrode assembly 22 and the first wall 211 is smaller, and the deformation transferred to the first wall 211 is larger when the electrode assembly 22 is expanded and deformed, so that the pulling force formed on the first wall 211 is larger, the pressure relief portion 3 is easily damaged, and the reliability of the pressure relief portion 3 is not easily improved. If the gap h1 between the electrode assembly 22 and the first wall 211 is greater than 10mm, although the deformation transferred to the first wall 211 is small when the electrode assembly 22 is expanded and deformed, the probability of damage to the pressure relief portion 3 is also small, but this results in a large gap h1 between the electrode assembly 22 and the first wall 211, occupies a large space in the case 21, and results in a small volume of the electrode assembly 22 in the case 21, which is disadvantageous for improving the battery energy density.

In the above technical solution, by setting the gap h1 between the electrode assembly 22 and the first wall 211 within the range of 4mm to 10mm, the gap h1 between the electrode assembly 22 and the first wall 211 can be made more suitable, the degree of deformation of the first wall 211 is smaller when the electrode assembly 22 expands and deforms, the damage probability of the pressure release portion 3 is smaller, and meanwhile, the volume of the electrode assembly 22 in the housing 21 is larger, so that the battery cell 2 has better battery energy density.

In some embodiments of the present application, as shown in FIG. 4, the gap between the electrode assembly 22 and the second wall 212 is h2, where 0 < h 2.ltoreq.2 mm.

The gap h2 between the electrode assembly 22 and the second wall 212 may be, but is not limited to, 0mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2.0mm, and the like. If the gap h2 between the electrode assembly 22 and the second wall 212 is greater than 2mm, this may result in an increase in the volume ratio of the gap h2 within the case 21, and a decrease in the volume ratio of the electrode assembly 22, which is disadvantageous in improving the battery energy density of the battery cell 2.

In the above technical solution, by setting the gap h2 between the electrode assembly 22 and the second wall 212 within a range of 0-2 mm, on one hand, a certain distance is provided between the electrode assembly 22 and the second wall 212, and when the electrode assembly 22 expands and deforms, the time for transmitting to the second wall 212 is prolonged, which is favorable for weakening the deformation degree of the second wall 212, reducing the damage probability of the pressure relief portion 3, and on the other hand, the battery cell 2 can have a better battery energy density.

In some embodiments of the application, the housing 21 comprises a shell with an opening and an end cap closed to the opening, wherein the first wall 211 is formed in the end cap and the second wall 212 is formed in the shell.

In the above technical scheme, the casing and the end cover are separately arranged, the first wall 211 is arranged on the end cover, when the electrode assembly 22 deforms, the casing is firstly deformed and then is transferred to the end cover, as the end cover and the casing are two components, the acting force can generate loss at the joint position of the casing and the end cover during transfer, so that the stress on the end cover can be reduced, the deformation of the end cover is reduced, or the deformation probability of the end cover is reduced, and then the deformation of the first wall 211 is reduced, or the deformation probability of the first wall 211 is reduced, and the damage probability of the pressure relief part 3 on the first wall 211 is reduced.

In some embodiments of the application, the thickness of the end cap is greater than the wall thickness of the second wall 212. In this technical solution, since the thickness of the end cover is greater than the wall thickness of the second wall 212, the strength of the end cover 212 is greater than the strength of the second wall 212, and as can be seen from the foregoing, the pressure relief portion 3 is provided on the first wall 211, so that the damage probability of the pressure relief portion 3 can be reduced to a certain extent, and on this basis, by making the thickness of the end cover greater than the thickness of the second wall 212, the strength of the end cover is relatively high, the deformation degree of the first wall 211 is further reduced, or the deformation probability is reduced, so that the pulling force generated by the first wall 211 is further reduced, and the damage probability of the pressure relief portion 3 can be further reduced.

In some embodiments of the application, the end cap has a thickness t1 and the second wall 212 has a wall thickness t2, where 1.5mm < t 1.ltoreq.3mm and 0.8 mm.ltoreq.t2.ltoreq.1.5 mm.

The thickness t1 of the end cap may be, but is not limited to, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, and the like.

If the thickness t1 of the end cover is smaller than 1.6mm, the strength of the end cover is smaller, the deformation resistance is weaker, and the reliability of the pressure relief part 3 is not improved. If the thickness t1 of the end cover is greater than 3mm, the thickness of the end cover is relatively large, the strength of the end cover can far exceed the minimum strength required for resisting the deformation of the shell, and the performance of the end cover is excessive, so that the cost is increased. And secondly, the thickness of the end cover is larger, so that the weight of the end cover is increased, the weight of the battery cell 2 is increased, the overall weight of the battery module 10 is increased, and meanwhile, the thickness of the end cover is increased, so that the volume of the end cover is increased, and the energy density of the battery cell 2 and the battery module 10 is not improved.

The wall thickness t2 of the second wall 212 may be, but is not limited to, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, and the like. If the wall thickness t2 of the second wall 212 is less than 0.8mm, the second wall 212 is smaller in thickness, and also smaller in strength, and is poor in deformation resistance, and the second wall 212 is easily deformed when the electrode assembly 22 is expanded and deformed, which is disadvantageous in that the probability of damage to the pressure relief portion 3 on the second wall 212 is reduced, that is, the reliability of the pressure relief portion 3 is disadvantageous. Second, the smaller thickness of the second wall 212 also increases manufacturability and increases manufacturing costs. If the wall thickness t2 of the second wall 212 is greater than 1.5mm, the thickness of the second wall 212 is greater, the material cost thereof increases, and the duty ratio of the case in the battery cell 2 increases, which is disadvantageous for improving the battery energy density.

In the above technical scheme, through setting the thickness t1 of end cover in the within range of 1.5mm ~ 3mm, can take into account the intensity of end cover, material cost and the volume ratio in battery monomer 2 comprehensively, make intensity, material cost and the volume ratio in battery monomer 2 of end cover control in more reasonable within range on the one hand, on the other hand can compromise the reliability that improves pressure release portion 3. By setting the thickness t2 of the second wall 212 within a range of 0.8mm to 1.5mm, the strength, manufacturability, material cost and volume ratio in the battery cell 2 of the second wall 212 can be comprehensively considered, so that the strength, manufacturability, material cost and volume ratio in the battery cell 2 of the second wall 212 are controlled within a relatively reasonable range on the one hand, and the reliability of the pressure relief portion 3 can be improved on the other hand.

In some embodiments of the application, the wall thickness of the second wall 212 is equal to the wall thickness of the other on the housing.

In some embodiments of the present application, as shown in fig. 3, 5 and 6, an electrode terminal 213 is provided on the first wall 211, and a tab portion (not shown) is provided on the electrode assembly 22, the tab portion being electrically connected to the electrode terminal 213.

The electrode terminal 213 may refer to a post, which may include a positive post and a negative post, for electrically connecting an external power receiving part and a tab part. The tab portion may refer to a protruding portion of the electrode assembly 22 for electrically connecting the electrode terminal 213, and may include a positive tab electrically connected to the positive post and a negative tab electrically connected to the negative post.

In the above technical solution, the gap between the first wall 211 and the electrode assembly 22 can play a role in weakening the deformation influence of the electrode assembly 22 on the first wall 211 on one hand, and can play a role in providing a space required for bending the tab portion on the other hand, and by integrating the two functions at one place, the internal structure of the battery cell 2 is compact, and the energy density of the battery cell 2 can be improved.

In some embodiments of the application, the pressure relief portion 3 is located away from the center of the corresponding first wall 211 and/or the pressure relief portion 3 is located away from the center of the corresponding second wall 212.

It will be appreciated that the pressure relief portion 3 is disposed away from the center of the corresponding first wall 211; or the pressure release portion 3 is disposed away from the center of the corresponding second wall 212; or the pressure relief portion 3 is disposed away from the center of the corresponding first wall 211, and the pressure relief portion 3 is disposed away from the center of the corresponding second wall 212.

In the above technical solution, when the housing 21 deforms and causes the deformation of the first wall 211, the central position of the first wall 211 begins to deform first, and then the periphery of the first wall 211 deforms, that is, the central position of the first wall 211 is the deformation starting position and the deformation degree is larger than that of the periphery, so that the pressure release portion 3 is far away from the center of the corresponding first wall 211, so that the deformation of the position where the pressure release portion 3 is located is relatively smaller, and the pulling force applied to the pressure release portion 3 is also smaller, which is beneficial to reducing the damage probability of the pressure release portion 3. Similarly, when the housing 21 deforms and causes the second wall 212 to deform, the central position of the second wall 212 begins to deform first, and then the periphery of the second wall 212 deforms, that is, the central position of the second wall 212 is the deformation starting position and the deformation degree is larger than that of the periphery, so that the pressure release portion 3 is far away from the center of the corresponding second wall 212, so that the deformation of the position where the pressure release portion 3 is located is relatively smaller, and the pulling force applied to the pressure release portion 3 is also smaller, thereby being beneficial to reducing the damage probability of the pressure release portion 3.

In some embodiments of the application, the first wall 211 and the second wall 212 are disposed opposite or adjacent.

In the above technical solution, referring to fig. 4, the first wall 211 and the second wall 212 may be two opposite walls on the housing 21, that is, the pressure release portions 3 on the first unit 201 and the second unit 202 are disposed opposite to each other, when one of the first unit 201 and the second unit 202 is subject to thermal runaway, the pressure release portion 3 of one has less influence on the pressure release portion 3 of the other when the pressure release portion 3 of the other is subject to pressure release, so that the reliability of the battery unit 2 that is not subject to thermal runaway can be improved. The first wall 211 and the second wall 212 may be two adjacent walls on the housing 21, that is, the pressure release portions 3 on the first unit 201 and the second unit 202 are disposed adjacent to each other, so that when the plurality of battery units 2 are assembled, the first unit 201 and the second unit 202 are assembled easily and are distinguished, and occurrence of reverse assembly or wrong assembly can be reduced, and assembly efficiency is improved.

In some embodiments of the present application, as shown in fig. 3, 5, 6 and 7, the first wall 211 is a top wall of the housing 21 and the second wall 212 is a bottom wall of the housing 21.

In the above technical scheme, the battery module 10 is applied to the electric device, the battery module 10 is generally disposed at the bottom of the electric device, and is provided with electric components or personnel thereon, when the battery module 10 is out of control, the first monomer 201 at the outer side can exhaust and release pressure upwards, and the second monomer 202 at the middle position can exhaust and release pressure downwards, so that the fire condition in the area above the battery module 10 can be relieved, especially under the condition that the number of the second monomers 202 is large, the loss of the electric components is reduced, and the injury of personnel is reduced, that is to say, the influence on the electric device under the thermal runaway of the battery module 10 can be reduced by adopting the structure, and the use safety of the battery module 10 is improved.

In some embodiments of the application, the pressure relief portion 3 is integrally formed with the first wall 211 and/or the pressure relief portion 3 is integrally formed with the second wall 212.

That is, the pressure relief portion 3 is integrally formed with the first wall 211; or the pressure relief portion 3 is integrally formed with the second wall 212; alternatively, the pressure relief portion 3 is integrally formed with the first wall 211, and the pressure relief portion 3 is integrally formed with the second wall 212. A sinking groove (not shown) may be formed on the pressure relief portion 3, and a region of the pressure relief portion 3 corresponding to the sinking groove is a weak region. Wherein the sink grooves may include, but are not limited to, rectangular grooves, circular grooves, oval grooves. The pressure relief portion 3 may be provided with a score (not shown) that forms a weakened area in the pressure relief portion 3. The weak area of the pressure relief part 3 may be ruptured to relieve pressure when thermal runaway of the battery cell 2 occurs.

In some embodiments of the application, as shown in fig. 4, the pressure relief portion 3 and the first wall 211 are separately provided, and the pressure relief hole 21a is provided on the first wall 211, and the pressure relief portion 3 is sealed in the pressure relief hole 21a. For example, the pressure relief portion 3 may include, but is not limited to, a rupture disc, a burst valve, a safety valve, and the like.

In some embodiments of the application, as shown in fig. 4, the pressure relief portion 3 and the second wall 212 are separately provided, and the pressure relief hole 21a is formed in the second wall 212, and the pressure relief portion 3 is sealed in the pressure relief hole 21a. For example, the pressure relief portion 3 may include, but is not limited to, a rupture disc, a burst valve, a safety valve, and the like.

In some embodiments of the application, as shown in fig. 7, a thermal insulator 4 is provided between any adjacent two of the plurality of battery cells 2. The heat insulating member 4 may refer to a member capable of insulating heat, including but not limited to a heat insulating mat, and the like. In the above technical scheme, through setting up thermal-insulated piece 4 between arbitrary adjacent two battery monomer 2, can reduce the heat transfer before two adjacent battery monomer 2, can reduce the heat transfer when one of them battery monomer 2 takes place thermal runaway to the battery monomer 2 that does not take place thermal runaway on, and then can improve the reliability of the battery monomer 2 that does not take place thermal runaway.

In some embodiments of the present application, as shown in fig. 7, the battery module 10 further includes end plates 5, and the end plates 5 are provided at both ends of the module formed of the plurality of battery cells 2. In this technical scheme, end plate 5 can play the constraint effect at the both ends of the single module of a plurality of battery 2 to fix a plurality of battery 2, reduce the probability that a plurality of battery 2 take place not hard up, thereby improve the installation fastness of battery 2.

According to the embodiment of the application, the battery module 10 comprises a plurality of stacked battery cells 2, wherein the bottom wall of the battery cell 2 positioned in the middle position of the plurality of battery cells 2 is provided with a pressure relief part 3, and the top wall of the battery cell 2 positioned in the two ends is provided with the pressure relief part 3.

In a second aspect, as shown in fig. 2, an embodiment of the present application further provides a battery 100 including the battery module 10.

In the above technical scheme, because the influence of deformation of the battery cell 2 on the pressure relief portion 3 in the battery module 10 is relatively small, the probability of damage of the pressure relief portion 3 is relatively low, and the service performance and reliability of the battery module 10 can be improved, so that the reliability of the battery 100 with the battery module 10 is improved, the service life of the battery 100 is prolonged, and the service performance of the battery 100 is improved.

In a third aspect, an embodiment of the present application further provides an electrical device, including the foregoing battery module 10, or the foregoing battery 100.

In the above technical solution, the battery module 10 or the battery 100 is used as a critical component in the electric device, and the pressure relief portion 3 in the battery module 10 or the battery 100 is less affected by the deformation of the battery cell 2, and the probability of damaging the pressure relief portion 3 is lower, so that the reliability of the battery module 10 or the battery 100 is better, and the reliability and the safety of the whole electric device can be improved.

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

The above is only a preferred embodiment of the present application, and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (13)

1. A battery module, comprising:

The battery unit comprises a shell and an electrode assembly arranged in the shell, the shell is provided with a first wall and a second wall which are positioned outside the battery module, a gap between the electrode assembly and the first wall is larger than a gap between the electrode assembly and the second wall, the battery unit comprises a first unit and a second unit, the second unit is one or more and forms a unit group, the first unit is arranged at two opposite ends of the unit group, and a pressure release part is arranged on the first wall of the first unit and the second wall of the second unit.

2. The battery module according to claim 1, wherein the first cells are provided in plurality at opposite ends of the cell group.

3. The battery module of claim 1, wherein a gap between the electrode assembly and the first wall is h1, wherein 4mm ∈h1 ∈10mm.

4. The battery module according to claim 3, wherein a gap between the electrode assembly and the second wall is h2, wherein 0 < h2 is 2mm.

5. The battery module according to any one of claims 1 to 4, wherein the housing includes a case body and an end cap provided with an opening, the end cap being closed to the opening, wherein the first wall is formed at the end cap, and the second wall is formed at the case body.

6. The battery module of claim 5, wherein the end cap has a thickness greater than a wall thickness of the second wall.

7. The battery module of claim 6, wherein the end cap has a thickness t1 and the second wall has a wall thickness t2, wherein 1.5mm < t1.ltoreq.3mm and 0.8 mm.ltoreq.t2.ltoreq.1.5 mm.

8. The battery module according to any one of claims 1 to 7, wherein an electrode terminal is provided on the first wall, and a tab portion is provided on the electrode assembly, the tab portion being electrically connected to the electrode terminal.

9. The battery module according to any one of claims 1 to 8, wherein the pressure relief portion is provided away from a center of the corresponding first wall and/or the pressure relief portion is provided away from a center of the corresponding second wall.

10. The battery module of any one of claims 1 to 9, wherein the first wall and the second wall are oppositely disposed or adjacently disposed.

11. The battery module according to any one of claims 1 to 10, wherein the first wall is a top wall of the housing and the second wall is a bottom wall of the housing.

12. A battery comprising the battery module according to any one of claims 1 to 11.

13. An electric device comprising the battery module according to any one of claims 1 to 11, or the battery according to claim 12.