CELL UNIT, BATTERY PACK, AND ELECTRIC DEVICE

A cell unit includes a cell and a bracket. The cell includes a cell housing and an electrode terminal. The cell housing includes a body portion and a first sealing part. The first sealing part includes a first connection portion. The bracket includes a first portion. The first portion covers a part of the first connection portion. The first connection portion includes a first end face. The first end face includes a first region. The first portion includes a first section and a second section. The first section covers a part of the first end face and a part of an outer surface of the first connection portion. The second section is connected to the first section, the first region is located outside the second section. When viewed along a second direction, the first section and the second section form a notch. The first region is located in the notch.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Chinese Patent Application No. 202310796544.2, filed on Jun. 30, 2023, the disclosure of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

This application relates to the field of energy storage technologies, and in particular, to a cell unit, a battery pack, and an electric device.

BACKGROUND

In a cell of a battery pack, a cell housing is sealed by a sealing part. At present, the whole sealing part is typically enclosed by a bracket or protected through glue filling. However, this is not conducive to internal pressure relief of the cell and in turn affects the safety of the cell.

SUMMARY

In view of this, it is necessary to provide a cell unit, a battery pack, and an electric device, to facilitate pressure relief and reduce influence on the safety of the cell.

An embodiment of this application provides a cell unit including a cell and a bracket. The cell includes an electrode assembly, a cell housing, and an electrode terminal. The electrode terminal is connected to the electrode assembly and is extends out of the cell housing. The cell housing includes a body portion and a first sealing part. The electrode assembly is disposed in the body portion. The first sealing part includes a first connection portion. The electrode terminal extends out of the cell housing from the first connection portion. The bracket includes a first portion. The first portion and the body portion are arranged along a first direction. The first portion covers a part of the first connection portion. The electrode terminal extends out of the first portion. The first connection portion includes a first end face. The first end face includes a first region. The first portion includes a first section and a second section. The first section covers a part of the first end face and a part of an outer surface of the first connection portion. The second section is connected to the first section, and the first region is located outside the second section. When viewed along a second direction, the first section and the second section form a notch. The notch is facing away from the body portion. The first region is located in the notch. The first direction is perpendicular to the second direction. In this application, the first portion covers a part of the first connection portion to enhance protection for the first sealing part and improve the airtightness of the cell. The first region is located in the notch, the second section is connected to the first section, and the first region is located outside the second section; and therefore, when the cell swells, pressure in the cell first causes an impact on the second section, making the second section protrude in a direction away from the first connection portion, and then the pressure in the cell can be relieved through the first region in the notch, thereby facilitating pressure relief and improving the safety of the cell unit.

Optionally, in some embodiments of this application, the first section includes a first subsection and a second subsection. The first subsection and the second subsection are spaced apart along a third direction. The second section connects the first subsection and the second subsection. The electrode terminal extends out of the second subsection. The first direction, the second direction, and the third direction are perpendicular to each other.

Optionally, in some embodiments of this application, when viewed along the second direction, the second section is disposed between the first region and the body portion, facilitating pressure relief along the first direction.

Optionally, in some embodiments of this application, the first sealing part includes a first folded portion and a second folded portion. The first connection portion connects the first folded portion and the second folded portion. The first folded portion and the second folded portion are spaced apart along the third direction. The bracket includes a first side portion and a second side portion arranged along the third direction. The first portion connects the first side portion and the second side portion. The first side portion covers the first folded portion. The second side portion covers the second folded portion. When viewed along the second direction, the first connection portion is partially located between the first side portion and the second side portion in the third direction. The bracket covers a part of the first sealing part to enhance protection for the first sealing part. The first connection portion is partially disposed between the body portion and the first portion and between the first side portion and the second side portion to provide an expansion space for the first sealing part, thereby facilitating pressure relief.

Optionally, in some embodiments of this application, along the third direction, a distance between the electrode terminal and the notch is L1, and a distance between the electrode terminal and the first side portion is L2, where L1<½L2. This reduces damage to the electrode terminal caused by air pressure relieved from the first region in the notch and reduces the risk of affecting connection to an adjacent electrode terminal.

Optionally, in some embodiments of this application, a distance L3between the notch and the electrode terminal is less than a distance L4between the notch and the first side portion, so that more heat is produced at the electrode terminal, further facilitating pressure relief.

Optionally, in some embodiments of this application, the second section includes a first segment and a second segment. Along the second direction, the first segment and the second segment are disposed on two sides of the first connection portion.

Optionally, in some embodiments of this application, the first segment and the second segment are configured to protrude in a direction away from the first connection portion when receiving pressure from inside of the cell, facilitating pressure relief.

Optionally, in some embodiments of this application, the first connection portion includes two second sections. When viewed along the second direction, the first section and the second section form two notches. In the third direction, the electrode terminal is located between the two notches. The provision of the two notches further facilitates pressure relief, further improving the safety of the cell unit.

Optionally, in some embodiments of this application, when viewed along the second direction, a width of the notch along the third direction gradually decreases along the first direction, which helps to increase an accommodating space of the notch, so that the notch can accommodate more of the first connection portion and first region, thereby further facilitating pressure relief and improving the safety of the cell unit.

Optionally, in some embodiments of this application, the body portion includes a first wall. The first connection portion is connected to the first wall. The bracket includes a second portion. The second portion covers a part of the first wall, facilitating protection for the first sealing part. The second portion is spaced apart from the second section, facilitating pressure relief.

Optionally, in some embodiments of this application, when viewed along the second direction, the second portion, the first portion, the first side portion, and the second side portion enclose a first space; and the first connection portion is partially located in the first space. A periphery of the first connection portion is protected by the first portion, the first side portion, the second side portion, and the second portion, thereby reducing influence of swelling of the cell on sealing performance of the first sealing part.

Optionally, in some embodiments of this application, when viewed along the second direction, the first space is a closed space, facilitating pressure relief of the cell.

Optionally, in some embodiments of this application, the bracket includes an insulating bracket, which can reduce the risk of a short circuit in the cell.

Optionally, in some embodiments of this application, the bracket is integrally formed with the cell, helping to enhance connection strength between the bracket and the cell.

Optionally, in some embodiments of this application, when viewed along the second direction, the first connection portion includes a first connection region connected to the first end face and located in the notch, facilitating pressure relief of the cell.

Optionally, in some embodiments of this application, when viewed along the second direction, the first connection portion includes a second connection region located in the first space. The first connection region is spaced apart from the second connection region, helping to improve pressure relief of the cell.

Optionally, in some embodiments of this application, the second section is U-shaped, facilitating pressure relief of the cell.

Optionally, in some embodiments of this application, when viewed along the second direction, the notch is a U-shaped structure, facilitating pressure relief of the cell.

Optionally, in some embodiments of this application, along the first direction, the second section exceeds the first section, so that when the cell swells, the pressure in the cell can act on the second section in advance, facilitating pressure relief.

Optionally, in some embodiments of this application, when viewed along a direction opposite to the second direction, the first section and the second section form a notch, the notch is facing away from the body portion, and the first region is located in the notch, facilitating pressure relief.

Optionally, in some embodiments of this application, along the first direction, the second section and the first section have a distance H, satisfying H≥2 mm, which helps the pressure in the cell to first act on the second section, thereby facilitating pressure relief.

Optionally, in some embodiments of this application, when viewed along the first direction, in the second direction, the second portion does not exceed the body portion. When adjacent cell housings are in contact connection, a gap is present between adjacent second portions, reducing influence of pressure mutually applied by the adjacent cell housings on the second portion and reducing an acting force on the first sealing part, thereby facilitating protection for the first sealing part and facilitating connection stability between the bracket and the cell.

Optionally, in some embodiments of this application, when viewed along the first direction, in the second direction, the first side portion does not exceed the body portion. The second side portion does not exceed the body portion. When adjacent cell housings are in contact connection, a gap is present between adjacent first side portions, and a gap is present between adjacent second side portions, reducing influence of pressure mutually applied by the adjacent cell housings on the first side portions and the second side portions and reducing an acting force on the first sealing part, thereby facilitating the protection for the first sealing part and facilitating the connection stability between the bracket and the cell.

An embodiment of this application further provides a battery pack including a housing and further including a plurality of cell units according to any one of the foregoing embodiments, where the plurality of cell units are disposed in the housing.

Optionally, in some embodiments of this application, the battery pack includes a sampling member connected to the electrode terminal. Along the first direction, a projection of the notch is spaced apart from a projection of the sampling member, thereby reducing influence on the sampling member during pressure relieving.

An embodiment of this application further provides an electric device, including the battery pack according to any one of the foregoing embodiments.

In the cell unit, battery pack, and electric device of this application, the first portion covers a part of the first connection portion to enhance the protection for the first sealing part and improve the airtightness of the cell. The first region is located in the notch, the second section is connected to the first section, and the first region is located outside the second section; and therefore, when the cell swells, pressure in the cell first causes an impact on the second section, making the second section protrude in a direction away from the first connection portion, and then the pressure in the cell can be relieved through the first region in the notch, thereby facilitating pressure relief and improving the safety of the cell unit.

REFERENCE SIGNS OF MAIN COMPONENTS

This application is further described with reference to the accompanying drawings in the following some specific embodiments.

DETAILED DESCRIPTION

Some following specific embodiments are illustrative rather than restrictive, and are intended to provide basic understanding of this application but not to confirm critical or decisive elements or limit the protected scope of this application. As long as there is no structural conflict, the various technical features mentioned in all the embodiments can be combined in any manner.

When one component is assumed as being “disposed on/in” another component, the component may be disposed directly on/in the another component or with a component possibly present therebetween. When one component is assumed as being “connected to” another component, it may be connected to the another component directly or with a component possibly present therebetween.

It can be understood that the terms “perpendicular and equal to” are used to describe an ideal state of two components. During actual production or use, two components may be approximately perpendicular or equal to each other. For example, with reference to the description of numerical values, “perpendicular” may indicate that an included angle between two straight lines is within a range of 90°±10°, “perpendicular” may alternatively indicate that a dihedral angle of two planes is within a range of 90°±10°, and “perpendicular” may further alternatively indicate that an included angle between a straight line and a plane is within a range of 90°±10°. Two components described as “being perpendicular” to each other may not be absolutely straight lines or planes, or may be approximately straight lines or planes. From a macroscopic perspective, the component can be considered as a “straight line” or “plane” as long as its overall extension direction is a straight line or a plane.

The term “parallel” is used to describe an ideal state of two components. During actual production or use, two components may be approximately parallel to each other. For example, with reference to the description of numerical values, “parallel” may indicate that an included angle between two straight lines is within a range of 180°±10°, “parallel” may alternatively indicate that a dihedral angle of two planes is within a range of 180°±10°, and “parallel” may further alternatively indicate that an included angle between a straight line and a plane is within a range of 180°±10°. Two components described as “being parallel” to each other may not be absolutely straight lines or planes, or may be approximately straight lines or planes. From a macroscopic perspective, the component can be considered as a “straight line” or “plane” as long as its overall extension direction is a straight line or a plane.

Unless otherwise defined, the term “a plurality of” herein specifically indicates that there are two or more components when used to describe a quantity of components.

In the third direction Z, there is the third direction Z and a direction opposite to the third direction Z. In the first direction X, there is the first direction X and a direction opposite to the first direction X. In the second direction Y, there is the second direction Y and a direction opposite to the second direction Y.

For ease of description, some electrode terminals11care not folded.

Referring toFIG.1toFIG.15, an embodiment of this application provides a cell unit10. The cell unit10includes a cell11and a bracket12, where the bracket12is connected to the cell11. The cell11includes a cell housing11a, an electrode assembly11b, and an electrode terminal11c. The electrode terminal11cis connected to the electrode assembly11band is extend out of the cell housing11a. The cell housing11aincludes a body portion111and a first sealing part112. The electrode assembly11bis disposed in the body portion111. The first sealing part112includes a first connection portion112a. The electrode terminal11cextends out of the cell housing11afrom the first connection portion112a.

The bracket12includes a first portion121. The first portion121and the body portion111are arranged along the first direction X. The first portion121covers a part of the first connection portion112a. The electrode terminal11cextends from the first portion121. The first connection portion112aincludes a first end face1121, and the first end face1121includes a first region1121a. The first portion121includes a first section121aand a second section121b. The first section121acovers a part of the first end face1121and a part of an outer surface of the first connection portion112a. The second section121bis connected to the first section121a. The first region1121ais located outside the second section121b. When viewed along the second direction Y, the first section121aand the second section121bform a notch12a, the notch12ais facing away from the body portion111, and the first region1121ais located in the notch12a. The first direction X is perpendicular to the second direction Y.

In this application, the first portion121covers a part of the first connection portion112ato enhance protection for the first sealing part112and improve the airtightness of the cell11. The first region1121ais located in the notch12a, the second section121bis connected to the first section121a, and the first region1121ais located outside the second section121b; and therefore, when the cell11swells, pressure in the cell11first causes an impact on the second section121b, making the second section121bprotrude in a direction away from the first connection portion112a, and then the pressure in the cell11can be relieved through the first region1121ain the notch12a, thereby facilitating pressure relief and improving the safety of the cell unit10.

In some embodiments, when viewed along a direction Y′ opposite to the second direction Y, the first section121aand the second section121bform a notch12a, the notch12ais facing away from the body portion111, and the first region1121ais located in the notch12a, where the first connection portion112acan be rushed away by air pressure in the cell housing11ain the second direction Y, facilitating pressure relief.

In some embodiments, when viewed along the second direction Y, the second section121bis disposed between the first region1121aand the body portion111along the first direction X, facilitating pressure relief.

In some embodiments, along the first direction X, the second section121bexceeds the first section121a, facilitating pressure relief.

Referring toFIG.14toFIG.15, in some embodiments, the body portion111is provided with an accommodating space, and the body portion111includes a first housing111aand a second housing111b, the first housing111ais provided with a first recess1111, and the second housing111bis provided with a second recess1112. The first housing111ais connected to the second housing111bto form the accommodating space. The electrode assembly11bis partially disposed in the first recess1111and partially disposed in the second recess1112. A periphery of the first housing111aextends outward to form a first extension side1113. A periphery of the second housing111bextends outward to form a second extension side1114. After the first housing111ais connected to the second housing111b, the first extension side1113and the second extension side1114overlap and are hermetically connected.

In some embodiments, the body portion111is provided with an accommodating space, and the body portion111includes a first housing111aand a second housing111b, where the first housing111ais provided with a first recess1111, and the second housing111bis flat. The first housing111ais connected to the second housing111bto form the accommodating space. The electrode assembly11bis disposed in the first recess1111.

In some embodiments, the first extension side1113and the second extension side1114overlap and are hermetically connected to form two first sealing parts112and two second sealing parts113. The two first sealing parts112are arranged along the first direction X. The two second sealing parts113are arranged along the third direction Z. One first sealing part112is connected to the two second sealing parts113, and the other first sealing part112is connected to the two second sealing parts113.

In some embodiments, the cell11includes two electrode terminals11c, where one electrode terminal11cextends out of the cell housing11afrom one first sealing part112, and the other electrode terminal11cextends out of the cell housing11afrom the other first sealing part112.

In some embodiments, the body portion111includes a first wall111c, a second wall111d, a third wall111e, a fourth wall111f, a fifth wall111g, and a sixth wall111h. The first wall111cand the second wall111dare arranged along the first direction X. One first sealing part112is connected to the first wall111c, and the other first sealing part112is connected to the second wall111d. The third wall111eand the fourth wall111fare arranged along the third direction Z. One second sealing part113is connected to the third wall111e, and the other second sealing part113is connected to the fourth wall111f. The fifth wall111gand the sixth wall111hare arranged along the second direction Y.

In some embodiments, the body portion111includes two first walls111c, two second walls111d, and two first sealing parts112. One first wall111cis connected to a fifth wall111gand one first sealing part112, and the other first wall111cis connected to a sixth wall111hand one first sealing part112. One second wall111dis connected to the fifth wall111gand the other first sealing part112, and the other second wall111dis connected to the sixth wall111hand the other first sealing part112. One electrode terminal11cextends out of the cell housing11afrom one first sealing part112, and the other electrode terminal11cextends out of the cell housing11afrom the other first sealing part112.

When viewed along the first direction X, in the second direction Y, the two first walls111care located on two opposite sides of the first sealing part112. When viewed along a direction opposite to the first direction X, in the third direction Z, the two second walls111dare located on two opposite sides of the second sealing part113.

In some embodiments, the cell housing11aincludes a protective layer, a metal layer, and a polymer layer stacked in sequence. The protective layer is used to protect the metal layer, reduces the risk of damage to the metal layer caused by an external force, and also can slow down air permeation from an external environment. The metal layer may be an aluminum foil layer or a steel foil layer. The polymer layer has a property of being fused after heated, and can be used for packaging and sealing. In some embodiments, a metal layer at a first end face1121formed by cutting the cell housing11ais exposed. In this application, the first region1121ais located outside the second section121b, so that whether the cell housing11ais damaged during injection molding can be detected through the first region1121a.

Referring toFIG.1toFIG.4, in some embodiments, the first section121aincludes a first subsection1211and a second subsection1212, and the first subsection1211and the second subsection1212are spaced apart along the third direction Z. The second section121bconnects the first subsection1211and the second subsection1212, and the electrode terminal11cextends out of the second subsection1212. The first subsection1211, the second subsection1212, and the second section121bform a notch12a.

Referring toFIG.5toFIG.8, in some embodiments, the first connection portion112aincludes two second sections121b. When viewed along the second direction Y, the first section121aand the second section121bform two notches12a. In the third direction Z, the electrode terminal11cis located between the two notches12a.

In some embodiments, the first section121aincludes a first subsection1211, a second subsection1212, and a third subsection1213. The second subsection1212and the third subsection1213are spaced apart along the third direction Z. The second subsection1212is located between the first subsection1211and the third subsection1213. The electrode terminal11cextends out of the second subsection1212. One second section121bconnects the first subsection1211and the second subsection1212to form one notch12a. The other second section121bconnects the second subsection1212and the third subsection1213to form one notch12a. When viewed along the second direction Y, the electrode terminal11cis located between the two notches12aalong the third direction Z. The first end face1121includes a second region1121b, and the second region1121bis located in the other notch12a. The provision of the two notches12afurther facilitates pressure relief and in turn further improves the safety of the cell unit10.

In some embodiments, when viewed along the second direction Y, the second section121bis a U-shaped structure.

In some embodiments, when viewed along the second direction Y, the notch12ais a U-shaped structure.

Referring toFIG.10,FIG.12, andFIG.13, in some embodiments, in the first direction X, a distance d1between the second section121band the body portion111is less than a distance d2between the first section121aand the body portion111. Therefore, when the cell11swells, pressure in the cell11can first act on the second section121b, facilitating pressure relief.

In some embodiments, the second section121bincludes a first segment1214and a second segment1215. Along the second direction Y, the first segment1214and the second segment1215are disposed on two sides of the first connection portion112a. When the cell11does not swell, the first segment1214and the second segment1215are clamped on two sides of the first connection portion112ato enclose part of the first connection portion112a.

In some embodiments, the first segment1214and the second segment1215are configured to receive air pressure in the cell11and protrude in a direction away from the first connection portion112a, so that the air pressure in the cell11passes through the first connection portion112abetween the first segment1214and the second segment1215, moves to the first connection portion112ain the notch12a, and is discharged to the external environment through the first region1121a, thereby implementing pressure relief.

Referring toFIG.3, in some embodiments, along the first direction X, a distance H from a side of the second section121bfacing away from the first section121ato the first section121asatisfies H≥2 mm, which helps the pressure in the cell11to first act on the first segment1214and the second segment1215, so that the first segment1214and the second segment1215protrude, thereby facilitating pressure relief.

Referring toFIG.3andFIG.7, in some embodiments, when viewed along the second direction Y, a width of the notch12aalong the third direction Z gradually decreases along the first direction X, which helps to increase an accommodating space of the notch12a, so that the notch can accommodate more of the first connection portion112aand first region1121a, thereby further facilitating pressure relief and improving the safety of the cell unit10.

Referring toFIG.1,FIG.2, andFIG.4, in some embodiments, the first sealing part112includes a first folded portion112band a second folded portion112c, and the first connection portion112ais connected to the first folded portion112band the second folded portion112c. The first folded portion112band the second folded portion112care spaced apart along the third direction Z.

In some embodiments, the bracket12includes a first side portion122and a second side portion123, and the first portion121connects the first side portion122and the second side portion123. The first side portion122and the second side portion123are spaced apart along the third direction Z. The first side portion122covers the first folded portion112b, and the second side portion123covers the second folded portion112c.

When viewed along the second direction Y, the first connection portion112ais partially located between the body portion111and the first portion121along the first direction X, and the first connection portion112ais partially located between the first side portion122and the second side portion123in the third direction Z. The bracket12covers a part of the first sealing part112to enhance protection for the first sealing part112. The first connection portion112ais partially disposed between the body portion111and the first portion121and between the first side portion122and the second side portion123to provide an expansion space for the first sealing part112, thereby facilitating pressure relief.

In some embodiments, along the third direction Z, a distance between the electrode terminal11cand the notch12ais L1. Specifically, a distance between a side of the electrode terminal11cclose to the notch12aand a side of the notch12aclose to the electrode terminal11cis L1. Along the third direction Z, a distance between the electrode terminal11cand the first side portion122is L2. Specifically, a distance between a side of the electrode terminal11cclose to the first side portion122and a side of the first side portion122away from the electrode terminal11cis L2. L1<½L2, which reduces damage to the electrode terminal11ccaused by air pressure relieved from the first region1121ain the notch12aand reduces the risk of affecting connection to an adjacent electrode terminal11c.

In some embodiments, a distance L3between the notch12aand the electrode terminal11cis less than a distance L4between the notch12aand the first side portion122, so that more heat is produced at the electrode terminal11c, further facilitating pressure relief.

In some embodiments, the bracket12includes a second portion124, and the second portion124covers a part of the first wall111cto protect the body portion111. An end of the first portion121is connected to the first side portion122, and another end is connected to the second side portion123; and an end of the second portion124is connected to the first side portion122, and another end is connected to the second side portion123. This further enhances the structural strength of the bracket12, further facilitating the protection for the first sealing part112. The second portion124is spaced apart from the second section121b.

In some embodiments, when viewed along the second direction Y, the second portion124, the first portion121, the first side portion122, and the second side portion123enclose a first space12b; and the first connection portion112ais partially located in the first space12b. A periphery of the first connection portion112ais protected by the first portion121, the first side portion122, the second side portion123, and the second portion124, reducing influence of swelling of the cell11on sealing performance of the first sealing part112.

In some embodiments, when viewed along the second direction Y, the first space12bis a closed space, facilitating pressure relief of the cell11.

In some embodiments, when viewed along the second direction Y, the first connection portion112aincludes a first connection region112a1connected to the first end face1121, first connection region112a1located in the notch12a, facilitating pressure relief of the cell11.

In some embodiments, when viewed along the second direction Y, the first connection portion112aincludes a second connection region112a2located in the first space12b, and the first connection region112a1is spaced apart from the second connection region112a2, facilitating pressure relief of the cell11.

In some embodiments, when viewed along the first direction X, in the second direction Y, the second portion124does not exceed the body portion111, and the second portion124is located between the fifth wall111gand the sixth wall111h. The second portion124does not exceed the fifth wall111gin the second direction Y. The second portion124does not exceed the sixth wall111hin the second direction Y. When adjacent cell housings11aare in contact connection, a gap is present between adjacent second portions124, reducing influence of pressure mutually applied by the adjacent cell housings11aon the second portion124and reducing an acting force on the first sealing part112, thereby facilitating protection for the first sealing part112and facilitating connection stability between the bracket12and the cell11.

In some embodiments, when viewed along the first direction X, in the second direction Y, the first side portion122does not exceed the body portion111, and the second side portion123does not exceed the body portion111. When adjacent cell housings11aare in contact connection, a gap is present between adjacent first side portions122, and a gap is present between adjacent second side portions123, reducing influence of pressure mutually applied by the adjacent cell housings11aon the first side portions122and the second side portions123and reducing an acting force on the first sealing part112, thereby facilitating protection for the first sealing part112and facilitating connection stability between the bracket12and the cell11.

Referring toFIG.12, in some embodiments, the electrode assembly11bis a wound structure, and the electrode assembly11bincludes a first straight section1115, a second straight section1116, a first bent section1117, and a second bent section1118. The first straight section1115is connected to the first bent section1117and the second bent section1118, and the second straight section1116is connected to the first bent section1117and the second bent section1118. Along the third direction Z, a projection of the fifth wall111gcovers a projection of the first straight section1115, a projection of the sixth wall111hcovers the projection of the first straight section1115; the projection of the fifth wall111gcovers a projection of the second straight section1116; and the projection of the sixth wall111hcovers the projection of the second straight section1116, facilitating uniform pressure application between the cells11, thereby further prolonging the service life of the cells11.

In some embodiments, along the third direction Z, a projection of the first side portion122and a projection of the first bent section1117overlap, the projection of the first side portion122is spaced apart from the projection of the first straight section1115, and the projection of the first side portion122is spaced apart from the projection of the second straight section1116, facilitating pressure relief of the cell11.

In some embodiments, along the third direction Z, a projection of the second side portion123and a projection of the second bent section1118overlap, the projection of the second side portion123is spaced apart from the projection of the first straight section1115, and the projection of the second side portion123is spaced apart from the projection of the second straight section1116, facilitating pressure relief of the cell11.

Referring toFIG.1, in some embodiments, the bracket12includes a first extension portion125, the first extension portion125extends from the first side portion122, and the first extension portion125covers at least a part of the third wall111e. The first extension portion125can protect the third wall111eand the second sealing part113, enhancing the connection strength between the bracket12and the cell11.

In some embodiments, the bracket12includes a second extension portion126, the second extension portion126extends from the second side portion123, and the second extension portion126covers at least a part of the fourth wall111f. The second extension portion126can protect the fourth wall111fand the second sealing part113, enhancing the connection strength between the bracket12and the cell11.

In some embodiments, the bracket12is integrally formed with the cell11, facilitating the connection strength between the bracket12and the cell11. Optionally, the bracket12is integrally formed with the cell11through low-pressure injection molding.

In some embodiments, the bracket12is an insulating bracket, which can reduce the risk of a short circuit in the cell11.

In some embodiments, the cell unit10includes two brackets12, where one bracket12is connected to part of one first sealing part112, and the other bracket12is connected to part of the other first sealing part112. One electrode terminal11cextends out of the first sealing part112and the bracket12along the first direction X, and the other electrode terminal11cextends out of the second sealing part113and the bracket12along a direction opposite to the first direction X.

In some embodiments, the electrode terminals11clocated on a same side of two adjacent cell units10are connected to each other; one of the two adjacent brackets12of the cell unit10is provided with a notch12a; and the bracket12of the other cell unit10is provided with no notch12a.

In some embodiments, the electrode terminals11clocated on a same side of two adjacent cell units10are connected to each other, and two adjacent brackets12are each provided with the notch12a.

Referring toFIG.18toFIG.21, an embodiment of this application provides a battery pack100including a plurality of cell units10arranged along a second direction Y and a housing20, where the plurality of cell units10are disposed in the housing20.

In some embodiments, when disposed in the housing20, the cell units10are in a pressurized state.

In some embodiments, body portions111of adjacent cell housings11aare in contact connection, facilitating pressurization of the body portions111.

In some embodiments, the body portions111of the adjacent cell housings11aapply pressure to each other, so the plurality of cell units10are in a pressurized state, which is conducive to prolonging the service life of the cell units10.

In some embodiments, when viewed along the first direction X, in the second direction Y, the first portion121is located between the fifth wall111gand the sixth wall111h. A first gap12cis present between the first portions121on adjacent cells11. By virtue of the first gap12c, adjacent brackets12are spaced apart, and when the body portions111of the adjacent cells11apply pressure to each other, force applied to the first sealing part112can be reduced, and protection for the first sealing part112is enhanced.

In some embodiments, when viewed along the first direction X, in the third direction Z, the first side portion122does not exceed the first extension portion125, and a second gap12dis formed between adjacent first side portions122. When the adjacent cell housings11aare in contact connection and apply pressure to each other, the second gap12dbetween the two adjacent first side portions122can reduce an acting force applied to the first side portions122and reduce an acting force applied to the first sealing part112, facilitating the protection for the first sealing part112.

In some embodiments, when viewed along the first direction X, in a direction opposite to the third direction Z, the second side portion123does not exceed the second extension portion126, and a third gap12eis formed between adjacent second side portions123. When the adjacent cell housings11aare in contact connection and apply pressure to each other, the third gap12ebetween the two adjacent second side portions123can reduce an acting force applied to the second side portions123and thus further reduce an acting force applied to the first sealing part112, further facilitating the protection for the first sealing part112.

Referring toFIG.13toFIG.17, in some embodiments, the battery pack100further includes an elastic member30; the elastic member30is disposed between the cell units10and the housing20; and the elastic member30can apply pressure to the plurality of cell units10, to make the plurality of cell units10be in a pressurized state.

In some embodiments, the housing20includes a left wall21, a right wall22, a front wall23, a rear wall24, a top wall25, and a bottom wall26. The left wall21and the right wall22are arranged along the second direction Y. The front wall23and the rear wall24are arranged along the first direction X. The bottom wall26and the top wall25are arranged along the third direction Z. The left wall21is connected to the front wall23, the rear wall24, the top wall25and the bottom wall26, and the right wall22is connected to the front wall23, the rear wall24, the top wall25and the bottom wall26, to form an accommodating space. The plurality of cell units10and the elastic member30are disposed in the accommodating space. The plurality of cell units10and the elastic member30are arranged along the second direction Y.

In some embodiments, the bottom wall26is provided with a first limiting portion261and a second limiting portion262, where the first limiting portion261extends along the second direction Y, and the second limiting portion262extends along the second direction Y. The first limiting portion261and the second limiting portion262are arranged along the first direction X. The first limiting portion261and the second limiting portion262protrude from the bottom wall26along the third direction Z. When the bracket12is disposed in the housing20, the bracket12is located between the first limiting portion261and the second limiting portion262. When the cell11swells, the first limiting portion261and the second limiting portion262can limit movement of the bracket12along the first direction X, which helps the bracket12to move along the second direction Y.

In some embodiments, the top wall25is provided with a third limiting portion251and a fourth limiting portion252, where the third limiting portion251extends along the second direction Y, and the fourth limiting portion252extends along the second direction Y. The third limiting portion251and the fourth limiting portion252are arranged along the first direction X. The first limiting portion261and the third limiting portion251are arranged along the third direction Z. The second limiting portion262and the fourth limiting portion252are arranged along the third direction Z. The third limiting portion251and the fourth limiting portion252protrude from a surface of the top wall25facing the bottom wall26along a direction opposite to the third direction Z. When the bracket12is disposed in the housing20, the bracket12is located between the third limiting portion251and the fourth limiting portion252. When the cell11swells, the third limiting portion251and the fourth limiting portion252can limit movement of the bracket12along the first direction X, which helps the bracket12to move along the second direction Y.

In some embodiments, the elastic member30includes a base portion31and a folded portion32, where the base portion31is connected to the folded portion32, and the folded portion32is fixedly connected to the housing20. The base portion31is configured to be able to apply pressure to the cell unit10, and the folded portion32is configured to provide a swelling space for the cell unit10.

In some embodiments, when the cell11does not swell, the elastic member30applies no pressure to the cell unit10; and when the cell11swells, the cell11compresses the elastic member30, and the elastic member30applies pressure to the cell11.

In some embodiments, when the cell11does not swell, the elastic member30applies pressure to the cell11; and when the cell11swells, the cell11compresses the elastic member30, and the elastic member30applies higher pressure to the cell11.

In some embodiments, the base portion31is connected to a body portion111of an outermost cell11. The base portion31is provided with a plurality of protrusions311spaced apart along the first direction X, where a side of the base portion31facing the body portion111is recessed away from the body portion111to form the protrusions311, enhancing the structural strength of the base portion31and reducing the risk of deformation of the base portion31due to uneven force applied to the base portion31.

In some embodiments, the folded portion32includes a first folded portion321and a second folded portion322arranged along a direction opposite to the third direction Z, where the first folded portion321is connected to one side of the base portion31, and the second folded portion322is connected to another side of the base portion31. The first folded portion321and the second folded portion322can act on the cell unit10through the base portion31. The first folded portion321and the second folded portion322can provide a swelling space for the cell unit10.

In some embodiments, the elastic member30includes a first connection section323; the first connection section323is connected to a side of the first folded portion321facing away from the base portion31; the first connection section323is fixed to the housing20; and the first folded portion321is fixed to the housing20through the first connection section323, so that an acting force applied to the folded portion32can be transferred to the housing20.

In some embodiments, the first connection section323is parallel to the base portion31, facilitating deformation of the elastic member30in the second direction Y.

In some embodiments, the elastic member30includes a second connection section324; the second connection section324is connected to a side of the second folded portion322facing away from the base portion31; the second connection section324is fixed to the housing20; and the second folded portion322is fixed to the housing20through the second connection section324, so that an acting force applied to the folded portion32can be transferred to the housing20. For example, fixation is implemented through welding, adhesion, abutting, clamping, screwing, and the like.

In some embodiments, the second connection section324is parallel to the base portion31, facilitating deformation of the elastic member30in the second direction Y.

In some embodiments, the top wall25is provided with a first fixing portion (not shown in the figure). Along the second direction Y, a projection of the first connection section323and a projection of the first fixing portion overlap, and the first connection section323is fixed to the first fixing portion.

In some embodiments, the bottom wall26is provided with a second fixing portion263. Along the second direction Y, a projection of the first connection section323and a projection of the second fixing portion263overlap, and the first connection section323is fixed to the second fixing portion263. For example, fixation is implemented through welding, adhesion, abutting, clamping, screwing, and the like.

In some embodiments, the structural strength of the top wall25is higher than the structural strength of the elastic member30, reducing the risk of deformation of the top wall25caused by an acting force applied to the first folded portion321.

In some embodiments, the structural strength of the bottom wall26is higher than the structural strength of the elastic member30, reducing the risk of deformation of the bottom wall26caused by an acting force applied to the first folded portion321.

In some embodiments, the top wall25is thicker than the thickest one of the base portion31, the first folded portion321, and the first connection section323, enhancing the structural strength of the top wall25and reducing the risk of deformation of the top wall25caused by an acting force applied to the first folded portion321.

In some embodiments, the bottom wall26is thicker than the thickest one of the base portion31, the first folded portion321, and the first connection section323, enhancing the structural strength of the bottom wall26and reducing the risk of deformation of the bottom wall26caused by an acting force applied to the first folded portion321.

In some embodiments, the first folded portion321includes a first folded section321aand a second folded section321b, where the first folded section321ais connected to the base portion31, and the second folded section321bis connected to the first folded section321aand the first connection section323. The first folded section321aand the base portion31form a first included angle A1, the second folded section321band the first connection section323form a second included angle B1, and the first folded section321aand the second folded section321bform a third included angle C1, where A1≥B1, helping to enhance the capability of the first folded section321ain resisting deformation and helping to reduce the risk of deformation of the elastic member30in the second direction Y.

In some embodiments, C1>A1, helping to improve the uniformity of deformation of the first folded portion321.

In some embodiments, C1=2B1=2A1, helping to further improve the uniformity of the deformation of the first folded portion321.

In some embodiments, the second folded portion322includes a third folded section322aand a fourth folded section322b, where the third folded section322ais connected to the base portion31, and the fourth folded section322bis connected to the third folded section322aand the second connection section324. The third folded section322aand the base portion31form a first included angle A2, the fourth folded section322band the second connection section324form a second included angle B2, and the third folded section322aand the fourth folded section322bform a third included angle C2, where A2≥B2, helping to enhance the capability of the third folded section322ain resisting deformation and helping to reduce the risk of deformation of the elastic member30in the second direction Y.

In some embodiments, C2>A2, helping to improve the uniformity of deformation of the first folded portion321.

In some embodiments, C2=2B2=2A2, helping to further improve the uniformity of the deformation of the first folded portion321.

In some embodiments, the first folded portion321and the second folded portion322are the same in structure, facilitating the uniformity of stress and deformation.

Optionally, the second folded portion322is disposed at a same angle as the first folded portion321. When stressed, the first folded portion321and the second folded portion322can be stressed uniformly and deform uniformly, reducing the risk of rotation of the elastic member30caused by non-uniform deformation. Optionally, A1=A2, B1=B2, and C1=C2.

Referring toFIG.1, in some embodiments, the battery pack100includes a circuit board50, where the circuit board50is disposed between the elastic member30and the right wall22. The circuit board50is connected to a sampling assembly40and capable of receiving data acquired by the sampling assembly40. The circuit board50includes a BMS (Battery Management System) module. The BMS module includes a plurality of electronic components. The plurality of electronic components can achieve the functions such as control, protection, communication, power calculation, signal transmission, and electrical energy transmission for the cell11. Optionally, the circuit board50includes a flexible printed circuit (FPC, Flexible Printed Circuit). Optionally, the circuit board50includes a printed circuit board (FCB, Printed Circuit Board), and the circuit board50is provided with a plurality of wires (not shown in the figure).

In some embodiments, the battery pack100includes a sampling assembly40. The sampling assembly40is connected to any one of the electrode terminals11cof two adjacent cells11connected in a folded manner. The sampling assembly40can acquire at least one of voltage, current, or temperature of each cell11.

In some embodiments, the sampling assembly40includes a sampling member41and a sampling wire42. The sampling wire42is connected to the sampling member41and the circuit board50. The sampling member41is connected to any one of the electrode terminals11cof two adjacent cells11connected in a folded manner. Optionally, the sampling member41is welded to the electrode terminal11c. Along the first direction X, a projection of the sampling member41is spaced apart from a projection of the notch12a, which can reduce influence on the sampling member41during pressure relieving.

Referring toFIG.22, this application further provides an electric device200using the foregoing battery pack100. In an embodiment, the electric device200in this application may be, but is not limited to, an electronic device, a drone, a backup power source, an electric vehicle, an electric motorcycle, an electric motor bicycle, an electric tool, or a large household battery pack.

Persons of ordinary skill in the art should appreciate that some foregoing embodiments are for description of this application only but not for limiting this application. Appropriate modifications and variations made to some foregoing embodiments without departing from the essential spirit and scope of this application all fall within the scope of this application.