Battery pack and electric device
By providing grooves on the first beam of the battery pack to accommodate the curved portion on the electrical connection member, the problem of abnormal electrical connection caused by expansion of the battery cell is solved, and the energy density of the battery pack is improved.
Patent Information
- Application Number
- CN202421189005.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-27
- Publication Date
- 2025-06-20
- Estimated Expiration
- 2034-05-27
AI Technical Summary
In the battery pack, expansion of the battery cell causes abnormal connection between the electrical connector and the battery cell. The prior art adapts to expansion by providing curved portions on the electrical connector, but this takes up space and leads to waste of energy density.
A battery pack is designed, and a first beam is provided in the box with grooves on the first beam to accommodate the curved portion on the electrical connection member to prevent the curved portion from occupying additional space while ensuring the reliability of the electrical connection.
By providing grooves on the first beam of the battery pack to accommodate the curved portion, the problem of abnormal electrical connection is solved, and the energy density of the battery pack is increased, thereby avoiding waste of space.
Smart Images
Figure CN223006881U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, and particularly provides a battery pack and an electric device. Background Art
[0002] In an electric device (such as an electric vehicle), the battery system is one of the key systems, and the power battery pack (hereinafter referred to as the battery pack) is the core component of the battery system.
[0003] Inside the battery pack, multiple power battery monomers are usually stacked and connected in series / parallel through electrical connectors. However, during the use of the battery pack, the battery monomers may expand. During the expansion process, the distance between an electrical connector and each connection point of different battery monomers increases, and the connection points may be pulled, resulting in abnormal electrical connection.
[0004] In the art, a curved portion is usually provided on the electrical connector to adapt to the expansion. However, the design of the curved portion will inevitably lead to the occupation of the space inside the package, resulting in waste of the energy density of the battery pack. Summary of the Utility Model
[0005] In order to improve the energy density of the battery pack, the utility model provides a battery pack, which includes a box body. The box body includes a bottom plate, and a first beam is arranged on the bottom plate. A plurality of battery monomers and electrical connectors are further arranged inside the box body. The electrical connectors are electrically connected to the battery monomers. A curved portion is arranged on the electrical connectors, a groove is arranged on the first beam, and the curved portion is accommodated in the groove.
[0006] The arrangement of the curved portion on the electrical connector can adapt to the expansion of the battery monomers and ensure the reliability of the connection between the electrical connector and the battery monomers. The groove on the first beam accommodates the curved portion, which can avoid the curved portion occupying extra space inside the package and improve the energy density.
[0007] In an alternative technical solution of the utility model, the electrical connector includes a first connector, a second connector, and the curved portion connecting the first connector and the second connector; the arrangement direction of the first connector and the second connector is the same as the expansion direction of the battery monomers.
[0008] In an alternative technical solution of the utility model, along the first direction, the height H1 of the curved portion satisfies: 3mm ≤ H1 ≤ 20mm. If the height of the curved portion is too small, the stretching deformation ability of the electrical connector due to the expansion of the battery monomers is limited, and the improvement effect on abnormal electrical connection is limited. If the height of the curved portion is too large, it will cause material waste. Designing H1 within the above numerical range can adapt to the expansion while not wasting materials.
[0009] In an alternative technical solution of the present utility model, along the second direction, the width of the above-mentioned curved portion is D1, and the width of the above-mentioned groove is D2. D1 and D2 satisfy: 2mm ≤ D2 - D1 ≤ 30mm. Setting the difference between D1 and D2 within the above numerical range can ensure an appropriate spacing between the curved portion and the groove wall, protecting the curved portion from being damaged by the groove wall while avoiding the groove from being too wide, thus improving the energy density.
[0010] In an alternative technical solution of the present utility model, the center line of the above-mentioned curved portion coincides with the center line of the above-mentioned groove. Setting the center line of the curved portion to coincide with the center line of the groove can, while ensuring an appropriate gap between the curved portion and the groove, avoid the groove from being too wide, thereby improving the energy density. The center line of the curved portion and the center line of the groove may also deviate by less than or equal to 2mm in the second direction.
[0011] In an alternative technical solution of the present utility model, chamfers are provided at the inner wall ends of the above-mentioned groove, which can reduce the frictional force when the curved portion comes into contact with the inner wall of the groove accidentally.
[0012] In an alternative technical solution of the present utility model, an insulating layer is provided outside the above-mentioned curved portion, which can prevent abnormal electrical connection between the electrical connector and the groove wall. The insulating layer can also be a wear-resistant material, thus avoiding damage due to friction.
[0013] In an alternative technical solution of the present utility model, along the expansion direction of the above-mentioned battery cell, a plurality of the above-mentioned curved portions are provided on the above-mentioned electrical connector. When the battery cell expands greatly, the required size of the curved portion is relatively large. If only one curved portion is provided, the height of the curved portion needs to be set relatively large. If a plurality of curved portions are provided, the height of each curved portion can be reduced, thereby reducing the space in the height direction.
[0014] In an alternative technical solution of the present utility model, a plurality of the above-mentioned curved portions are accommodated in one of the above-mentioned grooves.
[0015] In an alternative technical solution of the present utility model, the above-mentioned battery pack further includes a buffer member, and the buffer member is disposed between two adjacent above-mentioned battery cells. The above-mentioned battery cell includes a first surface with the largest area, and the first surface faces the above-mentioned first beam.
[0016] The present utility model also provides an electrical device including the above-mentioned battery pack. Description of the Drawings
[0017] Figure 1 is a schematic diagram of the battery pack;
[0018] Figure 2 is Figure 1 a partial enlarged view of
[0019] Figure 3 isFigure 1 Cross-sectional view;
[0020] Figure 4 is Figure 3 Partial enlarged view;
[0021] Reference numeral
[0022] Bottom plate 1;
[0023] First beam 11;
[0024] Groove 111, chamfer 112;
[0025] Battery cell 2;
[0026] Buffer member 21;
[0027] Electrical connector 3;
[0028] Curved portion 31, first connector 32, second connector 33;
[0029] Insulating layer 311. Detailed implementation manners
[0030] The following describes the alternative implementation manners of the present utility model with reference to the accompanying drawings. Those skilled in the art should understand that these implementation manners are only used to explain the technical principle of the present utility model and are not intended to limit the protection scope of the present utility model.
[0031] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "distance", "width", "thickness", "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model 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 should not be construed as a limitation to the present utility model.
[0032] In the description of the present utility model, the terms "first", "second", "third", "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. In the description of the present utility model, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.
[0033] In addition, it should be noted that in the description of the present utility model, unless otherwise clearly specified and defined, the terms "arrangement" and "connection" 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, indirectly connected through an intermediate medium, or the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.
[0034] The present utility model provides a battery pack, which includes a box body and a plurality of battery cells arranged in the box body. The battery cells can include lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells, magnesium-ion battery cells, etc., and the embodiments of the present application do not limit this. The battery cells can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, and the embodiments of the present application do not limit this either.
[0035] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode plate, a negative electrode plate, and a separator. The battery cell mainly operates by the movement of metal ions between the positive electrode plate and the negative electrode plate. The positive electrode plate includes a positive current collector and a positive active material layer, and the positive active material layer is coated on the surface of the positive current collector; the positive current collector includes a positive coating area and a positive electrode tab connected to the positive coating area. The positive coating area is coated with the positive active material layer, and the positive electrode tab is not coated with the positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material, which can be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, etc. The negative electrode plate includes a negative current collector and a negative active material layer, and the negative active material layer is coated on the surface of the negative current collector; the negative current collector includes a negative coating area and a negative electrode tab connected to the negative coating area. The negative coating area is coated with the negative active material layer, and the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, and the negative active material layer includes a negative active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.
[0036] Such as Figure 1 and Figure 2As shown in the figure, the box body of the battery pack of the present application includes a box cover, an intermediate frame body, and a bottom plate 1. A first beam 11 is provided on the bottom plate 1. A plurality of battery cells 2 and electrical connectors 3 are further provided in the box body. The electrical connectors 3 are connected to the battery cells 2 so that the plurality of battery cells 2 form a series-parallel relationship. Since the battery cells 2 will expand during the charge and discharge process, a curved portion 31 is designed on the electrical connector 3 of the present application. The curved portion 31 can deform to a certain extent against the expansion of the battery cell 2 to ensure the reliability of the connection between the electrical connector and the battery cell. The design of the curved portion 31 will inevitably occupy space in the height direction. Therefore, a groove 111 is provided on the first beam 11 to accommodate the curved portion 31, thereby avoiding the curved portion 31 occupying additional space inside the package and ensuring the energy density of the battery pack.
[0037] In an alternative embodiment of the present invention, as Figure 1 shown, the box body of the battery pack includes two end plates. The first beam 11 divides the area between the two end plates into two chambers. A plurality of battery cells 2 are arranged in the chambers and are sandwiched between the end plates and the first beam 11. The battery cell 2 includes a first surface with the largest area, and the first surface faces the end plates and the first beam 11. A buffer member 21 may be provided between two adjacent battery cells 2. A plurality of battery cells 2 form a battery pack. When the battery pack is installed in the box body, a pressure can be applied to both sides of the battery pack by a tooling fixture first to compress the buffer member 21, and then it is placed into the chamber. The tooling fixture releases the pressure, and the buffer member 21 rebounds so that the battery pack is squeezed between the end plates and the first beam 11. The buffer member 21 can be bonded to the battery cell 2 by double-sided tape.
[0038] In an alternative embodiment of the present invention, as Figure 1-3 shown, the electrical connector 3 includes a first connector 32, a second connector 33, and a curved portion 31 connecting the first connector 32 and the second connector 33; the arrangement directions of the first connector 32 and the second connector 33 are the same as the expansion direction of the battery cell 2, that is, the same as the arrangement direction of the two end plates. The first connector 32 and the second connector 33 are respectively electrically connected to two battery cells 2 on both sides of the first beam 11, and the curved portion 31 is located in the groove 111 of the first beam 11. Specifically, the first connector 32 and the second connector 33 can be welded to the pole posts or pole ears of the battery cell 2.
[0039] In an alternative embodiment of the present invention, as Figure 3 and Figure 4As shown, along the first direction, the height H1 of the curved portion 31 satisfies: 3 mm ≤ H1 ≤ 20 mm. If the height of the curved portion 31 is too small, the ability of the electrical connection member to stretch and deform due to the expansion of the battery cell is limited, and the improvement effect on abnormal electrical connection is limited. If the height of the curved portion is too large, it will cause material waste. Designing H1 within the above numerical range can adapt to expansion while not wasting materials. Specifically, H1 can be 3 mm, 5 mm, 7 mm, 10 mm, 15 mm, 20 mm.
[0040] In an alternative embodiment of the present utility model, as Figure 3 and 4 shown, along the second direction, the width of the curved portion 31 is D1, and the width of the groove 111 is D2. D1 and D2 satisfy: 2 mm ≤ D2 - D1 ≤ 30 mm. Setting the difference between D1 and D2 within the above numerical range can ensure a suitable spacing between the curved portion 31 and the groove wall, protect the curved portion 31 from being damaged by the groove wall while avoiding the groove 111 from being too wide, and improve the energy density. Specifically, the difference between D2 and D1 can be 2 mm, 3 mm, 5 mm, 10 mm, 20 mm, 30 mm.
[0041] In an alternative embodiment of the present utility model, the center of the curved portion 31 coincides with the center of the groove 111. Setting the center of the curved portion 31 to coincide with the center of the groove 111 can avoid the groove from being too wide while ensuring a suitable gap between the curved portion 31 and the groove 111, and improve the energy density of the battery pack. Of course, the center line of the curved portion 31 and the center line of the groove 111 can also deviate by a relatively small distance. For example, the distance between the center line of the curved portion 31 and the center line of the groove 111 along the second direction is less than or equal to 2 mm. The smaller the deviation between the center line of the curved portion 31 and the center line of the groove 111, the better, and it is preferably completely coincident to minimize the size of the groove to the greatest extent.
[0042] In an alternative embodiment of the present utility model, as Figure 4 shown, a chamfer 112 is provided at the inner wall end of the groove 111, which can reduce the friction force when the curved portion 31 contacts the inner wall of the groove 111 accidentally.
[0043] In an alternative embodiment of the present utility model, as Figure 4 shown, an insulating layer 311 can be further provided outside the curved portion 31. The insulating layer 311 can prevent abnormal electrical connection between the electrical connection member 3 and the groove wall. The insulating layer 311 can also be a wear-resistant material, so as to avoid being damaged due to friction. For example, the insulating layer 311 can be a wear-resistant tape.
[0044] In an alternative embodiment of the present utility model, along the expansion direction of the battery cell 2 (i.e., the second direction), a plurality of curved portions 31 are provided on the electrical connector 3. When the battery cell 2 expands significantly, the size of the required curved portion 31 is relatively large. If only one curved portion 31 is provided, the height of this curved portion 31 needs to be set relatively large. If the electrical connector 3 includes a plurality of curved portions 31 along the second direction, the height of each curved portion 31 can be reduced, thereby reducing the space in the height direction.
[0045] In an alternative embodiment of the present utility model, as Figure 1-4 shown, a plurality of grooves 111 are provided on the first beam 11, and one curved portion 31 or a plurality of curved portions 31 can be received in the grooves 111.
[0046] The present utility model also provides an electrical device. The electrical device of the present utility model includes the battery pack of the alternative embodiment. By providing the battery pack, the force on the battery cells can be balanced, thereby improving the cycle life of the battery pack. The electrical device can be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, and the like. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric aircraft toy, and the like. The spacecraft can include an airplane, a rocket, a space shuttle, a spaceship, and the like.
[0047] So far, the technical solutions of the present utility model have been described in conjunction with the alternative embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present utility model is obviously not limited to these specific embodiments. Without departing from the principle of the present utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of the present utility model.
Claims
1. A battery pack, characterized in that: The battery pack comprises: The box body comprises a bottom plate, and a first beam is arranged on the bottom plate; A plurality of battery cells are disposed in the box; and An electrical connector electrically connected to the battery cell, wherein the electrical connector is provided with a curved portion; The first beam is provided with a groove, and the groove is used to accommodate the curved portion.
2. The battery pack according to claim 1, characterized in that: The electrical connector includes a first connector, a second connector, and the curved portion connecting the first connector and the second connector; The arrangement direction of the first connecting member and the second connecting member is the same as the expansion direction of the battery cell.
3. The battery pack according to claim 1, wherein: Along the first direction, a height H1 of the curved portion satisfies: 3 mm ≤ H1 ≤ 20 mm.
4. The battery pack according to claim 1, wherein: Along the second direction, the width of the curved portion is D1, the width of the groove is D2, and D1 and D2 satisfy: 2mm≤D2-D1≤30mm.
5. The battery pack according to claim 4, characterized in that: The center of the curved portion coincides with the center of the groove.
6. The battery pack according to claim 1, wherein: The inner wall end of the groove is chamfered.
7. The battery pack according to claim 1, characterized in that: An insulating layer is arranged outside the curved portion.
8. The battery pack according to claim 1, wherein: A plurality of the curved portions are provided on the electrical connector along the expansion direction of the battery cell.
9. The battery pack according to claim 1, characterized in that: One of the grooves accommodates a plurality of the curved portions.
10. The battery pack according to claim 1, wherein: The battery cell includes a first surface with a largest area, and the first surface faces the first beam.
11. The battery pack according to claim 1, wherein: The battery pack further includes a buffer member disposed between two adjacent battery cells.
12. An electrical device, characterized in that: A battery pack comprising the battery pack as claimed in any one of claims 1 to 11.