CN220556618U - Battery pack, battery pack and electric equipment - Google Patents

Abstract

The application relates to a battery pack, a battery pack and electric equipment. The battery pack includes: a first battery cell including a first battery cell and a second battery cell including a second battery cell stacked in a first direction; the first battery cell comprises a first electrode lug, and the second battery cell comprises a second electrode lug; the electric connecting piece is arranged between the first tab and the second tab and comprises a body part, a first connecting part and a second connecting part which are respectively arranged at two sides of the body part; the connecting surface of the first connecting part is electrically connected with the first tab, and the connecting surface of the second connecting part is electrically connected with the second tab; the included angle between the plane of the first tab and the first side surface of the first battery cell is 0-5 degrees, the included angle between the plane of the second tab and the first side surface of the second battery cell is 0-5 degrees, and the first side surface is the surface with the largest surface area of the battery cell. Thereby reducing the pulling of the tab and improving the cycle times of the battery monomer.

Description

Battery pack, battery pack and electric equipment

Technical Field

The application relates to the technical field of batteries, in particular to a battery pack, a battery pack and electric equipment.

Background

The battery is used as a main power source and plays an important role in the new energy automobile. At present, one type of battery cell of a battery pack is a soft pack cell, and a tab of the soft pack cell extends from an end face of the cell. When the tabs of the plurality of soft package battery cells are connected in series and parallel, an electric connector is generally adopted to electrically connect the plurality of tabs. However, at present, when the electric connector is electrically connected to a plurality of tabs, the form of the electric connector and the connection angle between the electric connector and the tabs are not studied deeply, and the tabs deflect at an angle relative to the side surface of the battery cell after connection, so that the tabs are pulled under stress, and the performance and the cycle life of the battery cell are affected. In addition, the electrical connector lacks sufficient support, so that the tab has poor stability after being connected with the electrical connector, and is easy to pull in the process of assembly or use. On the other hand, the current assembly form of the soft package battery cells in the battery pack is usually a battery module with a shell, and several soft package battery cells are installed in one shell, and then the module is installed in the battery pack. The battery module form of the small unit does not put forward too high requirements on the electric connection of the tab and the fixation of the tab, but the module shell occupies the inner space of the battery pack and cannot meet the design requirements of the battery pack with high energy density.

Disclosure of Invention

Based on this, the present application provides a battery pack, a battery pack and electric equipment to solve or at least improve the problems mentioned in the background art.

In one aspect, the present application provides a battery pack comprising: a first battery cell and a second battery cell stacked along a first direction, the first battery cell including a first battery cell, the second battery cell including a second battery cell, the first battery cell and the second battery cell each including two oppositely disposed end faces, two oppositely disposed first side faces, and two oppositely disposed second side faces; wherein the area of the first side surface is larger than the area of the end surface and larger than the area of the second side surface; the first battery cell comprises a first tab extending from an end face thereof, and the second battery cell comprises a second tab extending from an end face thereof; the electric connecting piece is arranged between the first tab and the second tab; the electric connector comprises a body part, a first connecting part and a second connecting part, wherein the first connecting part and the second connecting part are respectively arranged at two sides of the body part; the connecting surface of the first connecting part is electrically connected with the first tab, and the connecting surface of the second connecting part is electrically connected with the second tab; the included angle between the plane where the first tab is located and the first side face of the first battery cell is 0-5 degrees, and the included angle between the plane where the second tab is located and the first side face of the second battery cell is 0-5 degrees.

The design ensures that the plane of the tab of the battery cell is parallel to the first side surface or has a small angle after the tab of the battery cell is connected with the electric connecting piece, and when the included angle is 0-5 degrees, the tab is stressed very little or even not stressed, so that the phenomenon that the tab is stressed and pulled is improved, the performance and the cycle life of the battery cell are improved, and the design and the actual use requirements can be met.

Further, the first connection portion, the second connection portion, the first tab and the second tab all extend along the second direction, and a distance between a connection surface of the first connection portion and a connection surface of the second connection portion is equal to a distance between the first tab and the second tab.

Further, the battery pack further comprises a supporting piece, the supporting piece is arranged between the electric connecting piece and the first battery unit and between the electric connecting piece and the second battery unit, and the electric connecting piece is fixedly connected with the supporting piece.

Further, the support member includes a support body and a guide portion provided above the support body, and the guide portion includes a peripheral wall and a bottom wall, the peripheral wall having an opening in a direction facing the first battery cell and the second battery cell.

Further, in the second direction, the bottom wall is inclined downward toward a direction approaching the opening, and an included angle between the bottom wall and a horizontal plane is 3 ° -15 °.

Further, the support body is provided with a protrusion, the first connecting portion and the second connecting portion are provided with notches, and the notches are clamped with the protrusions.

Further, the first battery unit includes a plurality of battery cells arranged along a second direction, the first battery cell is located at an end of the first battery unit, and/or the second battery unit includes a plurality of battery cells arranged along the second direction, and the second battery cell is located at an end of the second battery unit.

Further, the electric connector is welded with the first tab and the second tab; the electric connecting piece is also provided with a positioning part; and/or the supporting piece is provided with a bearing part.

In another aspect, the present application provides a battery pack including a plurality of battery packs arranged in a first direction; the battery pack is the battery pack according to any one of the above technical schemes; and a cold plate disposed between two adjacent battery packs.

Further, the battery pack further includes a bus bar connected with the electrical connectors of the plurality of battery packs.

Finally, the application also provides an electric device, which comprises the battery pack.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application, illustrate and explain the application and are not to be construed as limiting the application.

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural view of a battery pack according to an embodiment of the present application.

Fig. 2 is a schematic structural view of an end portion of a battery pack according to an embodiment of the present application.

Fig. 3 is a schematic structural diagram of an electrical connector according to an embodiment of the present application.

Fig. 4 is a schematic structural view of a support member according to an embodiment of the present application.

Fig. 5 is one of the cross-sectional views of the support member of the embodiment of the present application.

Fig. 6 is a partial schematic structure of a battery pack according to an embodiment of the present application.

Fig. 7 is a partial enlarged view at a in fig. 6 and shows an exploded view.

Detailed Description

In order to make the above objects, features and advantages of the present application more comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is, however, susceptible of embodiment in many other forms than those described herein and similar modifications can be made by those skilled in the art without departing from the spirit of the application, and therefore the application is not to be limited to the specific embodiments disclosed below.

In the description of the present application, it should be understood that, if there are terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., these terms refer to the orientation or positional relationship based on the drawings, which are merely for convenience of description and simplification of description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, if any, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the terms "plurality" and "a plurality" if any, mean at least two, such as two, three, etc., unless specifically defined otherwise.

In this application, unless explicitly stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly. For example, the two parts can be fixedly connected, detachably connected or integrated; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, the meaning of a first feature being "on" or "off" a second feature, and the like, is that the first and second features are either in direct contact or in indirect contact through an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that if an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. If an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein, if any, are for descriptive purposes only and do not represent a unique embodiment.

Referring to fig. 1 and 2, a battery pack 100 according to an embodiment of the present application is shown, where the battery pack 100 includes: the first battery cell 110 and the second battery cell 120 stacked in the first direction X, the first battery cell 110 including a first battery cell 111, the second battery cell 120 including a second battery cell 121, the first battery cell 111 including a first tab 111a extending from an end face thereof, the second battery cell 121 including a second tab 121a extending from an end face thereof. Of course, it is understood that the positive and negative tabs of the battery cell according to the present application extend from two opposite end surfaces of the battery cell, so that the first tab 111a and the second tab 121a may be both positive tabs or both negative tabs, or one of them is a positive tab and the other is a negative tab. In this embodiment, specifically, the first tab 111a and the second tab 121a are both positive tabs or both negative tabs.

In addition, with continued reference to fig. 1 and 2, each of the first battery cell 111 and the second battery cell 121 includes two end surfaces disposed opposite to each other in the second direction Y, two first side surfaces disposed opposite to each other in the first direction X, and two second side surfaces disposed opposite to each other in the third direction Z, wherein the first side surfaces are surfaces having the largest surface area among the surfaces. Under the condition that the battery monomer is not assembled with an electric connecting piece or other battery pack structures, the tab extends out of the end face of the battery monomer, and the plane where the tab is located is coincident with or parallel to the first side face.

Alternatively, each of the first and second battery cells 110 and 120 may be provided to have one battery cell or a plurality of battery cells arranged in the second direction Y. When the first battery cell 110 and the second battery cell 120 each have only one battery cell, the first battery cell 111 and the second battery cell 121 are described above. When the first battery cell 110 and the second battery cell 120 each have a plurality of battery cells arranged in the second direction Y, as shown in fig. 1 and 2, in the present embodiment, the first battery cell 111 refers to a battery cell located at an end of the first battery cell 110, and the second battery cell 121 refers to a battery cell located at an end of the second battery cell 120. Of course, in other implementations, for example, when the first battery cell 110 and the second battery cell 120 each have more than two battery cells along the second direction Y, the first battery cell and the second battery cell may also refer to battery cells located in the middle of the battery cells.

With continued reference to fig. 1 and 2, to achieve electrical connection between the battery cells of the battery pack, the first tab 111a of the first battery cell 111 and the second tab 121a of the second battery cell 121 are electrically connected by the electrical connector 300. In the present embodiment, the first tab 111a, the second tab 121a and the electrical connector 300 are all located at the end of the battery pack 100. It is understood that one battery pack 100 includes two electrical connectors 300, which are respectively disposed at both ends of the battery pack 100. In other embodiments, when the battery unit has a plurality of battery cells, other tabs of the battery cells of the first battery cell 110 and the second battery cell 120 are electrically connected through the electrical connector, so the electrical connector 300 can also be used to electrically connect the tabs at non-end portions of the battery pack 100, and further connect the battery cells in series-parallel to form the battery pack 100. Of course, it is understood that the structural form of the electrical connection member can be adaptively adjusted according to the requirements of the tab electrical connection.

In the present embodiment, referring to fig. 2 and 3, the electrical connector 300 is located between the first tab 111a and the second tab 121 a; the electrical connector 300 includes a body portion 301, a first connection portion 310 and a second connection portion 320 extending from both sides of the body portion 301; optionally, the first connecting portion 310 and the second connecting portion 320 are integrally formed with the body portion 301. Wherein, the connection surface of the first connection portion 310 is connected with the first tab 111a, and the connection surface of the second connection portion 320 is connected with the second tab 121 a; and in the connection state, an included angle between the plane of the first tab 111a and the first side of the first battery cell 111 is 0 ° -5 °, and an included angle between the plane of the second tab 121a and the first side of the second battery cell 121 is 0 ° -5 °.

The design ensures that the plane of the tab of the battery cell is parallel to the first side surface or has a small angle after the tab of the battery cell is connected with the electric connecting piece, and when the included angle is 0-5 degrees, the tab is stressed very little or even not stressed, so that the phenomenon that the tab is stressed and pulled is improved, the performance and the cycle life of the battery cell are improved, and the design and the actual use requirements can be met. The applicant found in the study that when the tab is connected with the electrical connector, if the angle between the plane of the tab and the first side of the battery cell is too large, when the angle is larger than 5 degrees, the tab of the battery cell is pulled under stress, so that the lithium is separated from the pole piece in the battery cell under the action of stress, the cycle number of the battery cell can be seriously affected, and the design and use requirements cannot be met. According to the design of the electric connecting piece, the angle of deflection after the lug is connected with the electric connecting piece is controlled simultaneously, and the requirements of the performance and the cycle times of the battery cell and the battery pack are met. Illustratively, the angles are 0 °,1 °,2 °,3 °,4 °,5 °, etc.

Further, the first connection portion 310, the second connection portion 320, the first tab 111a and the second tab 121a all extend along the second direction, the distance between the connection surface of the first connection portion 310 and the connection surface of the second connection portion 320 is L1, the distance between the first tab 111a and the second tab 121a is L2, where l1=l2, that is, the distance between the connection surface of the first connection portion 310 and the connection surface of the second connection portion 320 is equal to the distance between the first tab 111a and the second tab 121a, so that in the state that the tabs are connected with the electrical connection member, the plane where the first tab 111a is located is parallel to the first side surface of the first battery cell 111, and the plane where the second tab 121a is located is parallel to the first side surface of the second battery cell 121, that is, the included angle between the two is 0 °. In this case, the tab is minimally stressed, with a better number of cycles.

With continued reference to fig. 1, 2, 4, and 5, the battery pack 100 further includes a support member 200, where the support member 200 is disposed between the electrical connector 300 and the first and second battery cells 111 and 121, and the electrical connector 300 is fixedly connected to the support member 200. Therefore, after the first tab 111a and the second tab 121a are connected to the electrical connector 300, the support member 200 can support the electrical connector 300, and further support the first tab 111a and the second tab 121a connected to the electrical connector 300 and fix the positions thereof, so that excessive pulling of the tabs in the connection and use processes can be prevented, the connection stability is improved, and the performance and the service life of the battery cell are ensured.

Specifically, the shape of the supporting body 210 is adapted to the shape of the electrical connector 300, so as to facilitate the electrical connector 300 to be fixedly mounted on the supporting body 210. Optionally, the supporting body 210 is provided with a protrusion 211, the first connecting portion 310 and the second connecting portion 320 of the electrical connector 300 are provided with a notch 302, and the notch 302 and the protrusion 211 are clamped, so that the two are fixed. Wherein, the protrusion 211 is provided with a cylindrical structure, the notch 302 is provided with a C-shaped structure, and the clamping is realized through interference fit. Further, a plurality of protrusions 211 are provided and distributed on the support body 210; correspondingly, a plurality of notches 302 are also formed, so that the stability of the clamping is further improved.

The battery pack of this embodiment is no longer installed in the module casing, but directly installs in the box of battery package, therefore has all put forward higher requirement to the electric connection stability of utmost point ear and the mechanical strength of utmost point ear department. Based on this, in this embodiment, the space at the tab, that is, between two tabs and in the periphery thereof is filled with the foaming glue and/or the potting glue, so that it fills the space not occupied by the battery pack member, thereby improving mechanical strength and providing excellent electrical insulation, while fixing the position of the tab with respect to the battery pack, improving stability of electrical connection.

Specifically, the support 200 includes a support body 210 and a guide 220, the guide 220 is disposed above the support body 210, and the guide 220 includes a peripheral wall 221 and a bottom wall 222, the peripheral wall 221 having openings in a direction facing the first battery cell 111 and the second battery cell 121. With continued reference to fig. 5, in the second direction Y, the bottom wall 222 is inclined downwardly in a direction approaching the opening, the bottom wall 222 being at an angle of 3 ° to 15 ° to the horizontal. Therefore, when the glue is injected, the glue injection nozzle of the glue injection device aligns with the guide portion 220, the peripheral wall 221 blocks the glue from overflowing, and when the glue reaches the bottom wall 222, the bottom wall 222 has a certain downward inclination angle, so that the glue can be guided to flow downwards from the opening of the peripheral wall 222, and then flows between the first tab 111a and the second tab 121a. The guiding portion 220 is disposed above the supporting body 210, and is also disposed above the first tab 111a and the second tab 121a, so that the glue filling nozzle is prevented from touching the tabs and damaging the tabs during filling glue.

Alternatively, the first tab 111a and the second tab 121a are soldered to the electrical connector 300. In order to improve the welding precision, in this embodiment, a positioning portion 303 is further provided on the electrical connector 300, and the positioning portion 303 is used to be captured by a vision device during welding. For example, during soldering, the CCD camera of the soldering apparatus can capture the positioning portion 303, thereby positioning the electrical connector 300 to avoid soldering misalignment.

Optionally, the supporting piece 200 is provided with a bearing part 212, and the bearing part 212 is used for bearing the acting force of the welding fixture during welding. For example, when the first tab 111a, the second tab 121a and the electrical connector 300 are welded, the welding jig is abutted against the electrical connector 300, the acting force is transmitted to the support member 200 through the electrical connector 300, and the bearing portion 212 is provided on the support member 200, so that the reaction force can be applied to the electrical connector 300 through the bearing portion 212, and the welding acting force is prevented from being directly transmitted to the tab through the electrical connector 300 to damage the battery cell.

Referring to fig. 6 and 7, the battery pack in the present embodiment includes a plurality of battery packs 100 arranged in a first direction; and a cold plate 400 extending in the second direction and disposed between two adjacent battery packs 100. So that the cold plate 400 contacts and transfers heat to the battery pack 100 to perform temperature control of the battery pack 100.

Specifically, the cold plate 400 is in thermal contact with the first side surface of the first battery unit 111 and the first side surface of the second battery unit 121, where the first side surface is the surface with the largest surface area of each surface of the first battery unit 111 and the second battery unit 121, that is, the cold plate 400 is in contact with the side surface with the largest surface area in the battery units, so that the heat exchange area is increased, and the heat exchange efficiency is improved.

Further, referring to fig. 1 and 2, in the battery pack 100, a buffer 130 is further disposed between the cells of the first battery cell 110 and the cells of the second battery cell 120, that is, the buffer 130 is disposed between the first battery cell 111 and the second battery cell 121. In this way, the buffer 130 is used to absorb the expansion of the battery cell, especially when the battery cell is a soft-pack battery cell. Optionally, the buffer 130 is foam, which has heat insulation properties in addition to the function of absorbing the expansion of the cell, and can suppress the diffusion of thermal runaway.

With continued reference to fig. 6 and 7, the battery pack further includes a bus bar 500, where the bus bar 500 is disposed at one end of the battery pack 100 and is connected to the electrical connectors 300 of the plurality of battery packs 100. Specifically, the connection may be performed by welding. In the present embodiment, four battery packs 100 are shown, and four battery packs 100 arranged in sequence are defined as a first battery pack, a second battery pack, a third battery pack and a fourth battery pack, wherein the polarities of the battery cells in the first battery pack and the second battery pack are the same as the polarities of the tabs connected with the electric connector 300; the polarity of the tabs connected with the electrical connector 300 of the cells in the third and fourth battery packs is the same, and the polarity of the tabs connected with the electrical connector 300 of the cells in the first and second battery packs is opposite. For example, the tabs of the first and second battery packs connected to the electrical connector 300 are positive tabs, and the tabs of the third and fourth battery packs connected to the electrical connector 300 are negative tabs; or, the tabs of the first battery pack and the second battery pack, where the battery cells are connected with the electrical connector 300, are all negative tabs, and the tabs of the third battery pack and the fourth battery pack, where the battery cells are connected with the electrical connector 300, are all positive tabs. In this way, the first battery pack and the second battery pack are connected in parallel, the third battery pack and the fourth battery pack are connected in parallel, and then the first battery pack and the second battery pack are connected in series through the connection of the bus bars 500, so that the electric connection of the plurality of battery packs 100 in the battery pack is realized. Of course, in other embodiments, the polarities of the tabs connected to the electrical connector 300 are the same in the first, second, third and fourth battery cells, so that the plurality of battery packs 100 are connected in parallel through the bus bar 500.

In another aspect, the present application also provides a powered device comprising a battery pack 100 as above. For example, the electric equipment is an electric automobile or energy storage equipment.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the claims. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims (11)

1. A battery pack, comprising:

a first battery cell and a second battery cell stacked along a first direction, the first battery cell including a first battery cell, the second battery cell including a second battery cell, the first battery cell and the second battery cell each including two oppositely disposed end faces, two oppositely disposed first side faces, and two oppositely disposed second side faces; wherein the area of the first side surface is larger than the area of the end surface and larger than the area of the second side surface;

the first battery cell comprises a first tab extending from an end face thereof, and the second battery cell comprises a second tab extending from an end face thereof;

the electric connecting piece is arranged between the first tab and the second tab; the electric connector comprises a body part, a first connecting part and a second connecting part, wherein the first connecting part and the second connecting part are respectively arranged at two sides of the body part;

the connecting surface of the first connecting part is electrically connected with the first tab, and the connecting surface of the second connecting part is electrically connected with the second tab; the included angle between the plane where the first tab is located and the first side face of the first battery cell is 0-5 degrees, and the included angle between the plane where the second tab is located and the first side face of the second battery cell is 0-5 degrees.

2. The battery pack according to claim 1, wherein the first connection portion, the second connection portion, the first tab, and the second tab each extend in a second direction, and a distance between a connection surface of the first connection portion and a connection surface of the second connection portion is equal to a distance between the first tab and the second tab.

3. The battery pack of claim 1 or 2, further comprising a support member disposed between the electrical connector and the first and second battery cells, the electrical connector being fixedly connected to the support member.

4. The battery pack according to claim 3, wherein the support member includes a support body and a guide portion provided above the support body, and the guide portion includes a peripheral wall and a bottom wall, the peripheral wall having openings in a direction facing the first battery cell and the second battery cell.

5. The battery of claim 4, wherein in the second direction, the bottom wall is inclined downward toward a direction proximate to the opening, the bottom wall being at an angle of 3 ° to 15 ° from horizontal.

6. The battery pack according to claim 4, wherein the support body is provided with a protrusion, and the first connecting portion and the second connecting portion are each provided with a notch, and the notch and the protrusion are engaged with each other.

7. The battery pack of claim 1, wherein the first battery cell comprises a plurality of battery cells arranged in a second direction, the first battery cell being located at an end of the first battery cell, and/or,

the second battery unit comprises a plurality of battery cells arranged along a second direction, and the second battery cells are positioned at the end parts of the second battery unit.

8. The battery of claim 3, wherein the electrical connection is welded to the first tab and the second tab;

the electric connecting piece is also provided with a positioning part; and/or the supporting piece is provided with a bearing part.

9. A battery pack, wherein the battery pack comprises a plurality of battery packs arranged in a first direction; the battery pack is the battery pack according to any one of claims 1 to 8;

and a cold plate disposed between two adjacent battery packs.

10. The battery pack of claim 9, further comprising a buss bar connected with the electrical connections of a plurality of the battery packs.

11. A powered device comprising the battery pack of claim 9 or 10.