Battery and electrical device

Abstract

An embodiment of the present application provides a battery and an electrical device. The battery (200) includes: a box body assembly (1), including a box body (11) and a fixing beam (12) fixed in the box body (11); a battery module (2), arranged in the box body (11) and including a plurality of battery cells (21); a first constraint member (3), configured to cover the battery module (2) and be fixed to the fixing beam (12); and a second constraint member (4), located on a side of the first constraint member (3) away from the battery module (2) and fixed to the fixing beam (12). A weak area (413) is provided on the second constraint member (4). The second constraint member (4) is configured to apply a binding force to the first constraint member (3) and allow the battery cells (21) to expand in the weak area (413).

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to a battery and an electrical device using the same. Background Art

[0002] Due to the advantages of high energy density, high power density, multiple cycle uses, and long storage time of lithium-ion batteries and the like, they have been widely used in electric vehicles.

[0003] However, extending the reliability and lifespan of the batteries used in electric vehicles has always been a difficult problem in the industry. Summary of the Invention

[0004] The purpose of this application is to improve the reliability and safety of battery operation.

[0005] According to the first aspect of this application, a battery is provided, including:

[0006] A box body assembly, including a box body and a fixed beam fixed in the box body;

[0007] A battery module, arranged in the box body and including a plurality of battery cells;

[0008] A first constraint member, used to cover the battery module and fixed to the fixed beam; and

[0009] A second constraint member, located on the side of the first constraint member away from the battery module and fixed to the fixed beam. The second constraint member is provided with a weak area, and the second constraint member is configured to apply a binding force to the first constraint member and allow the battery cells to expand in the weak area.

[0010] In some embodiments, the second constraint member and the first constraint member are stacked.

[0011] In some embodiments, the battery cell includes an electrode assembly, and the weak area is correspondingly arranged with the area where the electrode assembly is located.

[0012] In some embodiments, the weak area penetrates through in the thickness direction of the second constraint member.

[0013] In some embodiments, the battery cell has a side facing the first constraint member, and the side has four side edges;

[0014] The second constraint member applies a binding force to the first constraint member on at least part of the side edges of the side.

[0015] In some embodiments, the first restraint member includes a first limiting portion for covering the battery module, and the second restraint member includes a second limiting portion stacked outside the first limiting portion; the battery module includes a plurality of battery cells arranged along a first direction, and the four side edges include: a second side edge extending along a second direction, and the second direction is perpendicular to the first direction within the side surface;

[0016] Wherein, the second limiting portion includes a transverse restraint bar configured to apply a binding force at the second side edge.

[0017] In some embodiments, in the first direction, the adjacent second side edges of adjacent battery cells are force-constrained by the same transverse restraint bar.

[0018] In some embodiments, the four side edges further include: a first side edge extending along the first direction, and the second limiting portion further includes: two longitudinal restraint bars, which are arranged at intervals along the second direction and both extend along the first direction, and the longitudinal restraint bars are configured to apply a binding force at the first side edge;

[0019] Wherein, the transverse restraint bar is located between the two longitudinal restraint bars, and the two ends of the transverse restraint bar are respectively connected to the two longitudinal restraint bars.

[0020] In some embodiments, the second limiting portion includes a plurality of transverse restraint bars, and the areas enclosed between adjacent transverse restraint bars and the two longitudinal restraint bars form weak areas.

[0021] In some embodiments, fixing beams are provided on both sides of the battery module along the second direction;

[0022] The first restraint member includes: a first limiting portion and two first mounting portions, the first limiting portion is used for covering the battery module, and the two first mounting portions are respectively connected to both sides of the first limiting portion along the second direction;

[0023] The second restraint member includes: a second limiting portion and two second mounting portions, the second limiting portion is stacked outside the first limiting portion, and the two second mounting portions are respectively connected to both sides of the second limiting portion along the second direction;

[0024] Wherein, the first limiting portion and the second limiting portion on the same side are fixed to the same fixing beam.

[0025] In some embodiments, the whole of the first limiting portion protrudes away from the battery module relative to the first mounting portion, and the whole of the second limiting portion protrudes away from the battery module relative to the second mounting portion.

[0026] In some embodiments, the battery further includes:

[0027] An outer cover, which is arranged on the side of the second restraint member away from the first restraint member and closes the open end of the box body.

[0028] According to a second aspect of the present application, there is provided an electrical device, including the battery of the above embodiment, and the battery is used to provide electrical energy for the electrical device.

[0029] For the battery of the embodiment of the present application, by providing a second constraint member outside the first constraint member, a binding force can be applied to the first constraint member through the second constraint member, so as to jointly provide a binding force to the battery module through the first constraint member and the second constraint member. Moreover, by providing a weak area on the second constraint member, on the basis of allowing the battery cell to expand in the weak area, the binding force on the expansion surface of the battery cell can be increased, thereby improving the expansion rate of the battery cell and reducing the probability of battery failure caused by the battery cell squeezing the battery structural member after expansion, thereby improving the reliability and service life of the battery operation. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to the drawings without creative efforts.

[0031] Figure 1 It is a schematic structural diagram of some embodiments of installing the battery of the present application in a vehicle.

[0032] Figure 2 It is a schematic structural diagram of some embodiments of the battery of the present application.

[0033] Figure 3 It is an exploded view of some embodiments of the battery cell in the battery of the present application.

[0034] Figure 4 It is an exploded view of the internal structure of some embodiments of the battery of the present application.

[0035] Figure 5 It is a schematic diagram of the internal structure of some embodiments of the battery of the present application.

[0036] Figure 6 It is a schematic diagram of the installation relationship between the first constraint member, the second constraint member and the battery module in some embodiments of the battery of the present application.

[0037] Figure 7 、 Figure 8 and Figure 9 They are respectively a perspective view, a top view and a side view of some embodiments of the combination of the first constraint member and the second constraint member in the battery of the present application.

[0038] In the drawings, the drawings are not drawn to actual scale.

[0039] Marking Description:

[0040] 100, Vehicle; 101, Axle; 102, Wheel; 103, Motor; 104, Controller;

[0041] 200, Battery; 211, Housing; 212, Electrode Assembly; 213, Connection Part; 214, Adapter; 215, End Cap; 215A, End Cap Body; 215B, Positive Terminal; 215C, Negative Terminal; 215D, Explosion - proof Valve;

[0042] 1, Box Assembly; 11, Box; 12, Fixed Beam;

[0043] 2, Battery Module; 21, Battery Cell;

[0044] 3, First Constraint Component; 31, First Limiting Portion; 32, First Mounting Portion; 321, First Mounting Hole; 322, First Positioning Hole;

[0045] 4, Second Constraint Component; 41, Second Limiting Portion; 411, Longitudinal Constraint Strip; 412, Transverse Constraint Strip; 413, Weak Area; 42, Second Mounting Portion; 421, Second Mounting Hole; 422, Second Positioning Hole;

[0046] 5, Outer Cover;

[0047] 6, Fastener;

[0048] S, Side; B1, First Side Edge; B2, Second Side Edge; X, First Direction; Y, Second Direction; Z, Third Direction. Detailed Embodiment

[0049] The following further describes in detail the embodiments of the present application in conjunction with the drawings and examples. The detailed descriptions and drawings of the following examples are used to exemplarily illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0050] In the description of the present application, it should be noted that unless otherwise specified, the meaning of "a plurality" is two or more; the orientation or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range.

[0051] The orientation terms used in the following description are all the directions shown in the figures, and do not limit the specific structure of the present application. In the description of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0052] In order to clearly describe each orientation in the following embodiments, the following defines each direction. Taking Figure 4 the coordinate system of... as an example, the first direction X is located in a plane perpendicular to the height direction of the battery 200. For example, the first direction X represents the length direction of the battery 200; the second direction Y is also located in a plane perpendicular to the height direction of the battery 200 and perpendicular to the first direction X. For example, the second direction Y represents the width direction of the battery 200; the third direction Z is perpendicular to the plane formed by the first direction X and the second direction Y. For example, the third direction Z represents the height direction of the battery 200.

[0053] In Figure 4 embodiments other than..., the first direction X can also represent the width direction of the battery 200, and the second direction represents the length direction of the battery 200; or the first direction X represents any direction in a plane perpendicular to the height direction of the battery 200.

[0054] Based on this orientation definition, descriptions of orientation or positional relationships using terms such as "upper", "lower", "top", "bottom", "front", "rear", "inner", and "outer" are only for the convenience of describing the present application, and do not indicate or imply that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the protection scope of the present application.

[0055] As part of the inventive process of the present application, the inventors have conducted numerous tests and verifications and found that the reasons for the relatively low reliability and lifespan of the battery may be:

[0056] For batteries with multiple battery cells placed flat in a box, the bottom and top plates of the box are relied on to restrain the expansion surfaces of the battery cells. Compared with batteries with battery cells placed vertically, the restraining force on the expansion surfaces of the battery cells is small, and they are prone to expansion. When the battery cells inside the battery expand to a certain extent (for example, 16%), it may cause the structural components of the battery to deform or fail due to excessive stress. Moreover, the deformation degrees of the top plate and the expansion surface of the battery cell are inconsistent, the bonding surface between the battery cell and the top plate is severely delaminated, and the restraining effect of the top plate on the battery cell is weakened, which may cause the battery cell to shake in the box, or the structural components of the battery to deform or fail due to excessive stress. Moreover, if some battery cells expand to a large extent, it will force the entire top plate to arch and deform, and at the same time, it will also affect the restraining effect of other battery cells. The ability of the top plate to follow the deformation of the battery cell is poor.

[0057] If the thickness of the top plate is increased, although the restraining force of the top plate on the battery cell can be improved, it will also reduce the energy density of the battery. Therefore, a more effective method is needed to improve the restraining effect of the battery cell.

[0058] Batteries can be used in electrical devices, and the batteries are configured to supply electrical energy to the electrical devices. The electrical devices can be mobile phones, portable devices, laptop computers, battery cars, electric vehicles, ships, spacecraft, electric toys, and electric tools, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spaceships, etc., electric toys include fixed or mobile electric toys, for example, game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, etc., and electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, for example, electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact electric drills, concrete vibrators, and electric planers.

[0059] As Figure 1 shown, the electrical device can be a vehicle 100, such as a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc.; or the device using the battery can also be a drone or a ship, etc. The vehicle 100 includes a battery 200, and the battery 200 is used to supply electrical energy for the operation of the vehicle.

[0060] The vehicle 100 further includes an axle 101, wheels 102 connected to the axle 101, a motor 103, and a controller 104. The motor 103 is used to drive the axle 101 to rotate, the controller 104 is used to control the operation of the motor 103, and the battery 200 is used to supply electrical energy for the operation of the motor 103 and other components in the vehicle.

[0061] As Figure 2As shown, the battery 200 may include a box assembly 1, a battery module 2, and an outer cover 5. The inside of the box assembly 1 has a hollow structure, and the battery module 2 is accommodated in the box assembly 1. The box assembly 1 is used to provide an accommodation space for the battery module 2. In some embodiments, the outer cover 5 and the box assembly 1 are covered with each other to define an accommodation space for accommodating the battery module 2. Of course, the connection between the box assembly 1 and the outer cover 5 can be sealed by a sealing member (not shown in the figure), and the sealing member can be a sealing ring, a sealant, etc.

[0062] In the battery module 2, one or more battery cells 21 can be provided. If there are multiple battery cells 21, the multiple battery cells 21 can be connected in series, in parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple battery cells 21. The battery cell 21 can be a secondary battery in a cylindrical, square, or other shape.

[0063] As Figure 3 shown, the battery cell 21 may include a housing 211, an electrode assembly 212, and an end cap 215. The housing 211 has an opening, the electrode assembly 212 is accommodated in the housing 211, and the end cap 215 is used to close the opening of the housing 211. The end cap 215 includes an end cap body 215A, a positive terminal 215B, a negative terminal 215C, and an explosion-proof valve 215D provided on the end cap body 215A. One or more electrode assemblies 212 can be stacked, and two connection portions 213 are formed on each electrode assembly 212. Both connection portions 213 are connected to the positive terminal 215B and the negative terminal 215C through a transfer member 214.

[0064] Among them, the electrode assembly 212 may include a positive electrode plate, a negative electrode plate (not shown in the figure), and a separator (not shown in the figure). The electrode assembly 212 can be a wound structure formed by winding a positive electrode plate, a separator, and a negative electrode plate, or a stacked structure formed by laminating a positive electrode plate, a separator, and a negative electrode plate. The electrode assembly 212 also includes a positive electrode tab and a negative electrode tab. The positive current collector in the positive electrode plate that is not coated with the positive electrode active material layer can be used as the positive electrode tab, and the negative current collector in the negative electrode plate that is not coated with the negative electrode active material layer can be used as the negative electrode tab.

[0065] In some embodiments, such as Figure 4As shown in the figure, the present application provides a battery 200, including: a box body assembly 1, a battery module 2, a first restraint member 3, and a second restraint member 4. Among them, the box body assembly 1 includes a box body 11 and a fixed beam 12 fixed in the box body 11; the battery module 2 is arranged in the box body 11, and the battery module 2 includes a plurality of battery cells 21; the first restraint member 3 is used to cover the battery module 2 and is fixed to the fixed beam 12; the second restraint member 4 is located on the side of the first restraint member 3 away from the battery module 2 and is fixed to the fixed beam 12. A weak area 413 is provided on the second restraint member 4. The second restraint member 4 is configured to apply a binding force to the first restraint member 3 and allow the battery cells 21 to expand in the weak area 413.

[0066] For example, the fixed beam 12 can be arranged along the first direction X, and the first direction X can be the length direction or the width direction of the battery 200, etc. A plurality of fixed beams 12 can be arranged at intervals along the second direction Y, and the first restraint member 3 is fixed by two adjacent fixed beams 12. The fixed beam 12 can adopt a solid fixed beam or a hollow fixed beam, and its cross-section can be rectangular, trapezoidal or C-shaped, etc. Its upper surface can be set as a plane so as to fix the first restraint member 3 and the second restraint member 4 on the upper surface of the fixed beam 12, or the first restraint member 3 and the second restraint member 4 can also be fixed to the side surface of the fixed beam 12.

[0067] For example, the plurality of battery cells 21 can be arranged in one layer or multiple layers. Each layer of battery cells 21 includes one column or multiple columns of battery cells 21 arranged side by side along the second direction Y. Each column of battery cells 21 includes a plurality of battery cells 21 arranged side by side along the first direction X. Among them, the positive electrode plate and the negative electrode plate in the battery cell 21 are stacked along the third direction Z, and the battery cell 21 is prone to expand along the third direction Z.

[0068] For example, in order to improve the restraint effect, an adhesive layer is provided between the first restraint member 3 and the battery module 2, and they are adhered by glue or other sticky materials, for example.

[0069] In this embodiment of the present application, by arranging the second restraint member 4 outside the first restraint member 3, the second restraint member 4 can apply a binding force to the first restraint member 3, so as to jointly provide a binding force to the battery module 2 through the first restraint member 3 and the second restraint member 4. Moreover, by providing the weak area 413 on the second restraint member 4, on the basis of allowing the battery cells 21 to expand in the weak area 413, the binding force on the expansion surface of the battery cells 21 can be improved, thereby improving the expansion rate of the battery cells 21 and preventing the battery cells 21 from expanding excessively, resulting in serious deformation or fracture of structural components such as the first restraint member 3, causing the battery 200 to fail, and thus improving the working reliability and life of the battery 200.

[0070] Secondly, since the binding force on the battery cell 21 is increased by adding the second constraint member 4, the thickness of the housing 211 of the battery cell 21 is allowed to be reduced, thereby increasing the energy density of the battery cell 21.

[0071] Thirdly, in the case where an adhesive layer is provided between the first constraint member 3 and the battery module 2, by improving the degree of expansion of the battery cell 21, the degree of detachment of the adhesive layer between the first constraint member 3 and the battery module 2 can also be reduced, so as to ensure the binding force of the first constraint member 3 on the battery cell 21, improve the structural strength of the battery 200, prevent the battery 200 from failing, and thus improve the reliability and lifespan of the battery 200 during operation.

[0072] In some embodiments, as Figure 5 shown, the second constraint member 4 and the first constraint member 3 are stacked along the third direction Z. The second constraint member 4 can be in contact with the first constraint member 3.

[0073] This embodiment can enable the second constraint member 4 to more stably and effectively provide a binding force to the first constraint member 3, and it is easy to set a weak area 413 at a position corresponding to the expansion area of the battery cell 21. On the basis of allowing the battery cell 21 to expand in the weak area 413, the binding force on the expansion surface of the battery cell 21 can be increased.

[0074] In some embodiments, the battery cell 21 includes an electrode assembly 212, and the weak area 413 is correspondingly arranged in the area where the electrode assembly 212 is located. Since the battery cell 21 mainly expands at the position where the electrode assembly 212 is located, by setting the weak area 413 at a position corresponding to the electrode assembly 212, on the basis of increasing the binding force of the second constraint member 4 on the expansion surface of the battery cell 21, the expansion space of the electrode assembly 212 occupied by the second constraint member 4 while providing the binding force can be minimized, without affecting the expansion gap of the electrode assembly 212.

[0075] Furthermore, the weak area 413 completely covers the electrode assembly 212, so that the part of the second constraint member 4 outside the weak area 413 completely avoids the area where the electrode assembly 212 is located, which can not only increase the binding force on the expansion surface of the battery cell 21 through the second constraint member 4, but also avoid the expansion space of the electrode assembly 212 occupied by the second constraint member 4 when providing the binding force.

[0076] In some embodiments, as Figure 4 shown, the weak area 413 is provided to penetrate in the thickness direction of the second constraint member 4.

[0077] In this embodiment, by providing a weak zone 413 that penetrates the second restraint member 4, while ensuring the binding force on the battery cell 21, it is beneficial to reduce the influence of the setting of the second restraint member 4 on the expansion of the battery cell 21, provide an expansion space for the battery cell 21, and thus improve the working reliability and lifespan of the battery 200. Optionally, the weak zone 413 can also be a thickness-reduced portion, or the material strength of the weak zone 413 is less than that of other regions of the second restraint member 4 except for the weak zone 413.

[0078] In some embodiments, as Figure 4 and Figure 6 shown, the battery cell 21 has a side surface S facing the first restraint member 3, the side surface S is perpendicular to the third direction Z, and the side surface S has four side edges; the second restraint member 4 applies a binding force to the first restraint member 3 at at least some of the side edges of the side surface S.

[0079] In this embodiment, by the second restraint member 4 increasing the binding force at the side edge position of the battery cell 21, it is possible to improve the binding force on the battery cell 21 without affecting the expansion space of the battery cell 21, prevent the battery cell 21 from expanding excessively, resulting in serious deformation or fracture of structural members such as the first restraint member 3 and causing the battery 200 to fail, and thus improve the working reliability and lifespan of the battery 200.

[0080] In some embodiments, as Figure 4 and Figure 6 shown, the first restraint member 3 includes a first limiting portion 31 for covering the battery module 2, and the second restraint member 4 includes a second limiting portion 41 stacked outside the first limiting portion 31; the battery module 2 includes a plurality of battery cells 21 arranged along the first direction X, and the four side edges include: a second side edge B2 extending along the second direction Y, the second direction Y is perpendicular to the first direction X within the side surface S, and the second side edge B2 is perpendicular to the end cap 215. Among them, the second limiting portion 41 includes a transverse restraint bar 412, and the transverse restraint bar 412 is configured to apply a binding force at the second side edge B2.

[0081] In this embodiment, through the transverse restraint bar 412, a stable binding force can be applied to the second side edge B2 of the battery cell 21, without occupying the expansion space of the battery cell 21, nor affecting the energy density of the battery cell 21, ensuring power supply; and it can prevent the expansion of adjacent battery cells 21 from interfering with each other. Moreover, when an adhesive layer is provided between the first restraint member 3 and the battery module 2, the area between adjacent battery cells 21 is the position where the adhesive layer is most likely to peel off. By applying a binding force through the transverse restraint bar 412, the phenomenon of peeling off of the adhesive layer between the first restraint member 3 and the battery module 2 can be alleviated, so as to further ensure the binding force applied to the battery cell 21, improve the structural strength of the battery 200, prevent the battery 200 from failing, and thus improve the working reliability and lifespan of the battery 200.

[0082] In some embodiments, as Figure 6 shown, in the first direction X, force constraints are applied to the adjacent second side edges B2 of adjacent battery cells 21 through the same transverse constraint bar 412.

[0083] This embodiment can not only simplify the structure of the second constraint member 4, but also provide more stable constraint forces to adjacent battery cells 21 through the same transverse constraint bar 412.

[0084] In some embodiments, the four side edges further include: a first side edge B1 extending along the first direction X, and the second limiting portion 41 further includes: two longitudinal constraint bars 411, which are arranged at intervals along the second direction Y and both extend along the first direction X, and the longitudinal constraint bars 411 are configured to apply constraint forces at the first side edge B1. Among them, the transverse constraint bar 412 is located between the two longitudinal constraint bars 411, and both ends of the transverse constraint bar 412 are respectively connected to the two longitudinal constraint bars 411.

[0085] By providing two longitudinal constraint bars 411 in this embodiment, not only can a stable constraint force be formed on the first side edge B1 of the battery cell 21, but also the expansion space of the battery cell 21 is not occupied, the energy density of the battery cell 21 is not affected, and the power supply is ensured. Moreover, a frame structure can be formed between the two longitudinal constraint bars 411 and the transverse constraint bar 412, improving the overall stiffness of the second constraint member 4, so as to more effectively apply pressure to the first constraint member 3, so that on the basis of providing reliable constraints to the battery cell 21, the expansion space of the battery cell 21 is not affected, thereby improving the reliability and lifespan of the battery 200 during operation.

[0086] When the end cover 215 of the battery cell 21 is arranged outward along the second direction Y, the first side edge B1 is the side edge of the end cover 215. By constraining the head position of the battery cell 21 through the longitudinal constraint bar 411, the reliability of the high-voltage connection structure can be increased. Or, when the end cover 215 of the battery cell 21 is arranged inward along the second direction Y, the first side edge B1 is the side edge of the surface of the housing 211 opposite to the end cover 215.

[0087] In some embodiments, as Figure 7 and Figure 8 , the second limiting portion 41 includes a plurality of transverse constraint bars 412. The areas enclosed between adjacent transverse constraint bars 412 and the two longitudinal constraint bars 411 form weak areas 413, and the weak areas 413 are rectangular through slots. In order to reduce the stress on the second constraint member 4, rounded corners or chamfers can be provided at the four corners of the weak areas 413. Such a structure can form weak areas 413 with a relatively large area to avoid the expansion area of the battery cell 21, and the structure is simple and easy to process.

[0088] In some embodiments, such as Figure 4 and Figure 5 shown, fixed beams 12 are provided on both sides of the battery module 2 along the second direction Y; the first restraint member 3 includes: a first limiting portion 31 and two first mounting portions 32, the first limiting portion 31 is used to cover the battery module 2, and the two first mounting portions 32 are respectively connected to both sides of the first limiting portion 31 along the second direction Y; the second restraint member 4 includes: a second limiting portion 41 and two second mounting portions 42, the second limiting portion 41 is stacked outside the first limiting portion 31, and the two second mounting portions 42 are respectively connected to both sides of the second limiting portion 41 along the second direction Y. Among them, the first limiting portion 31 and the second limiting portion 41 on the same side are fixed to the same fixed beam 12.

[0089] For example, the first restraint member 3 and the second restraint member 4 can be formed by a sheet metal stamping process.

[0090] Such as Figure 4 、 Figure 7 and Figure 8 shown, a plurality of first mounting holes 321 are provided at intervals along the extending direction of the fixed beam 12 on both of the two first mounting portions 32, a plurality of second mounting holes 421 are provided at intervals along the extending direction of the fixed beam 12 on both of the two second mounting portions 42, and a plurality of third mounting holes are provided at intervals along the extending direction of the fixed beam 12 itself. A plurality of fasteners 6 respectively pass through the corresponding first mounting holes 321, second mounting holes 421 and third mounting holes to mount the first restraint member 3 and the second restraint member 4 on the fixed beam 12. For example, the fastener 6 can be a screw, a bolt or a rivet, etc. In order to improve the positioning accuracy of the first restraint member 3 and the second restraint member 4, a first positioning hole 322 can be provided on the first mounting portion 32, and a second positioning hole 422 can be provided on the second mounting portion 42 to perform positioning by a pin before being fixed by the fastener 6.

[0091] For the battery 200 of this embodiment, the first restraint member 3 and the second restraint member 4 are fixed to the fixed beam 12 by the same set of fasteners 6, which is easy to assemble, and when the battery module 2 expands, it can provide a stable and effective pressing force to each battery module 2, reducing the degree of expansion deformation of the battery module 2.

[0092] In some embodiments, such as Figure 9 shown, the whole of the first limiting portion 31 protrudes toward the side away from the battery module 2 relative to the first mounting portion 32, and the whole of the second limiting portion 41 protrudes toward the side away from the battery module 2 relative to the second mounting portion 42.

[0093] This embodiment can not only reduce the installation height of the fixed beam 12 and ensure the strength of the fixed beam 12, but also avoid the fastener 6 protruding from the top surface of the second limiting part 41 when the first mounting part 32 and the second mounting part 42 are fixed to the fixed beam 12 by the fastener 6, thus reducing the height of the battery 200. Moreover, the overall stiffness of the first restraint member 3 and the second restraint member 4 can be improved.

[0094] As Figure 2 shown, the battery 200 further includes an outer cover 5, which is arranged on the side of the second restraint member 4 away from the first restraint member 3 and closes the open end of the box body 11.

[0095] In this embodiment, since the battery module 2 is jointly restrained by the first restraint member 3 and the second restraint member 4, the deformation of the outer cover 5 can be reduced and the sealing performance of the battery can be improved. Moreover, by setting the first restraint member 3 and the second restraint member 4 to reduce the deformation of the outer cover 5, when the battery 200 is used in a vehicle, it can still be disassembled and assembled smoothly at the original installation position after long-term use, which can reduce the maintenance difficulty of the battery 200, and can also prevent the external force exerted on the installation structure members on the vehicle due to the deformation of the battery 200.

[0096] In some embodiments, as Figure 9 shown, the thickness of the part of the second restraint member 4 except the weak area 413 is greater than the thickness of the first restraint member 3. By setting the second restraint member 4 with a larger thickness, a more stable and reliable binding force can be exerted on the battery cell 21 through the first restraint member 3. By setting the first restraint member 3 with a smaller thickness, the battery cell 21 can more easily expand by overcoming the pressing force of the first restraint member 3 at the position where the weak area 413 is located, thereby improving the reliability and service life of the battery 200 during operation.

[0097] Next, in combination with Figures 4 to 9 , a specific embodiment of the battery 200 of the present application is given.

[0098] A plurality of fixed beams 12 are arranged along the second direction Y in the box body 1. The battery module 2 is arranged between adjacent fixed beams 12. The first restraint member 3 is used to cover the battery module 2 and is fixed to the fixed beams 12 on both sides. The second restraint member 4 is located on the side of the first restraint member 3 away from the battery module 2 and is fixed to the fixed beams 12. The first restraint member 3 and the second restraint member 4 can be fixed by the same set of fasteners 6.

[0099] The battery module 2 includes at least two columns of battery cells 21 arranged side by side in the second direction Y. Each column of battery cells 21 includes at least two layers of battery cells 21, and each layer of battery cells 21 includes a plurality of battery cells 21 arranged side by side in the first direction X. The battery cells 21 in at least two columns of battery cells 21 are aligned in the first direction X. Each battery cell 21 lies flat in the box body 11, and the positive electrode plate and the negative electrode plate in the electrode assembly 212 are stacked in the third direction Z. The electrode assembly 212 mainly expands in the third direction Z. The side surface S of the battery cell 21 is perpendicular to the third direction Z, and the side surface S is also the largest surface of the battery cell 21.

[0100] The first constraint member 3 entirely covers the battery module 2 and is fixed to the fixed beam 12. The second constraint member 4 is stacked with the first constraint member 3 and is located on the side of the first constraint member 3 away from the battery module 2 and is fixed to the fixed beam 12. The second limiting portion 41 contacts the first limiting portion 31 to provide a pressing force. A bonding layer may be provided between the first constraint member 3 and the top-layer battery cell 21, and a bonding layer may also be provided between the second constraint member 4 and the first constraint member 3 to improve the pressing effect of the second constraint member 4 on the first constraint member 3.

[0101] The second limiting portion 41 of the second constraint member 4 includes: two longitudinal constraint bars 411 and a plurality of transverse constraint bars 412.

[0102] The two longitudinal constraint bars 411 are spaced apart in the second direction Y and both extend in the first direction X. The two longitudinal constraint bars 411 are respectively used to constrain the first side edge B1 of the side surface S of the outermost two columns of battery cells 21. The first side edge B1 is located outside the battery cell 21, and the extending length of the longitudinal constraint bar 411 covers the first side edge B1 of the entire column of battery cells 21.

[0103] The plurality of transverse constraint bars 412 are spaced apart in the first direction X and all extend in the second direction Y. The two ends of each transverse constraint bar 412 are respectively connected to the two longitudinal constraint bars 411. The outermost two transverse constraint bars 412 are respectively used to constrain the second side edges B2 of the two outermost battery cells 21 in the first direction X, and the remaining transverse constraint bars 412 respectively constrain the second side edges B2 of the adjacent battery cells 21 in the first direction X. The extending length of the transverse constraint bar 412 covers the total dimension of at least two columns of battery cells 21 in the second direction Y. By providing the transverse constraint bars 412 at the second side edges B2 of the adjacent battery cells 21, the influence of the expansion of the battery cells 21 on the adjacent battery cells 21 can also be prevented.

[0104] A weak zone 413 is formed between two longitudinal restraint bars 411 and a plurality of transverse restraint bars 412. The weak zone 413 is a slot that penetrates the second restraint member 4 along the third direction Z. The setting area of this slot can correspond to the electrode assembly 212, so that both the longitudinal restraint bar 411 and the transverse restraint bar 412 avoid the electrode assembly 212, leaving space for the expansion of the electrode assembly 212. The widths of the longitudinal restraint bar 411 and the transverse restraint bar 412 can be designed according to the size of the electrode assembly 212. For example, the width range can be designed to be 2 mm to 20 mm, and the thickness range can be designed to be between 0.5 mm and 6 mm.

[0105] This embodiment can provide a binding force for a first side edge B1 and two second side edges B2 of a side surface S of the battery cell 21 opposite to the first restraint member 3, so as to obtain a better restraint effect. Optionally, a longitudinal restraint bar 411 can also be added between two adjacent columns of battery cells 21 to provide a binding force for all four side edges of the side surface S of the battery cell 21, so as to obtain a better restraint effect.

[0106] Although the present application has been described with reference to the preferred embodiments, various improvements can be made to it and components therein can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery (200), comprising: A box body assembly (1), including a box body (11) and a fixed beam (12) fixed in the box body (11); A battery module (2), disposed in the box body (11) and including a plurality of battery cells (21) arranged along a first direction (X), and the battery cells (21) include electrode assemblies (212); A first constraint member (3), configured to cover the battery module (2) and be fixed to the fixed beam (12); and A second constraint member (4), located on a side of the first constraint member (3) away from the battery module (2) and fixed to the fixed beam (12), a weak area (413) is provided on the second constraint member (4), and the weak area (413) is correspondingly arranged with the area where the electrode assembly (212) is located. The second constraint member (4) is configured to apply a binding force to the first constraint member (3), and allow the battery cell (21) to expand in the weak area (413); The second constraint member (4) includes two longitudinal constraint bars (411) and a plurality of transverse constraint bars (412), and the area enclosed between adjacent transverse constraint bars (412) and the two longitudinal constraint bars (411) forms the weak area (413). In the first direction (X), the adjacent sides of adjacent battery cells (21) along the first direction (X) are force-constrained by the same transverse constraint bar (412).

2. The battery (200) according to claim 1, wherein, The second constraint member (4) and the first constraint member (3) are stacked.

3. The battery (200) according to claim 1, wherein, The weak area (413) penetrates in the thickness direction of the second constraint member (4).

4. The battery (200) according to claim 1, wherein, The battery cell (21) has a side surface (S) facing the first constraint member (3), and the side surface (S) has four sides; The second constraint member (4) applies a binding force to the first constraint member (3) at at least part of the sides of the side surface (S).

5. The battery (200) according to claim 4, wherein, The first constraint member (3) has a first limiting portion (31) for covering the battery module (2), and the second constraint member (4) has a second limiting portion (41) stacked outside the first limiting portion (31); the four sides include: a second side (B2) extending along a second direction (Y), and the second direction (Y) is perpendicular to the first direction (X) in the side surface (S); Wherein, the second limiting portion (41) includes the transverse constraint bar (412), and the transverse constraint bar (412) is configured to apply a binding force at the second side (B2).

6. The battery (200) according to claim 5, wherein, The four sides further include: a first side (B1) extending along the first direction (X), and the second limiting portion (41) further includes: two longitudinal constraint bars (411), spaced apart along the second direction (Y) and both extending along the first direction (X), and the longitudinal constraint bars (411) are configured to apply a binding force at the first side (B1); The transverse restraint bar (412) is located between the two longitudinal restraint bars (411), and both ends of the transverse restraint bar (412) are respectively connected to the two longitudinal restraint bars (411).

7. The battery (200) according to any one of claims 1 to 6, wherein, The battery module (2) is provided with the fixing beam (12) on both sides along the second direction (Y); The first restraining component (3) comprises: a first limiting portion (31) and two first mounting portions (32), the first limiting portion (31) being used to cover the battery module (2), and the two first mounting portions (32) being respectively connected to two sides of the first limiting portion (31) along the second direction (Y); The second restraining component (4) comprises: a second limiting portion (41) and two second mounting portions (42), wherein the second limiting portion (41) is stacked on the outside of the first limiting portion (31), and the two second mounting portions (42) are respectively connected to both sides of the second limiting portion (41) along the second direction (Y); The first position-limiting portion (31) and the second position-limiting portion (41) located on the same side are fixed to the same fixed beam (12).

8. The battery (200) according to claim 7, wherein, The first limiting portion (31) as a whole protrudes relative to the first mounting portion (32) toward a side away from the battery module (2), and the second limiting portion (41) as a whole protrudes relative to the second mounting portion (42) toward a side away from the battery module (2).

9. The battery (200) according to any one of claims 1 to 6, further comprising: The outer cover (5) is provided on a side of the second restraining component (4) away from the first restraining component (3) and closes the open end of the box body (11).

10. An electrical device comprising the battery (200) according to any one of claims 1 to 9, wherein the battery (200) is used to provide electrical energy for the electrical device.

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