A battery cell, a battery and an electric device

Abstract

The present invention relates to the technical field of batteries, and discloses a battery cell, a battery, and an electrical device, comprising an electrode assembly and a shell, wherein the shell comprises a receiving portion and a wing extending from the receiving portion, the electrode assembly comprises a battery cell body and a first pole ear and a second pole ear connected to the battery cell body, and the battery cell body is received in the receiving portion; the battery cell body comprises a first pole piece, a diaphragm, and a second pole piece which are stacked and wound, the first pole piece comprises a first empty foil area located at the winding end of the battery cell body, the second pole piece comprises a second empty foil area located at the winding end of the battery cell body, and the first empty foil area and the second empty foil area extend from the battery cell body to the wing; one end of the first pole ear is connected to the first empty foil area, and one end of the second pole ear is connected to the second empty foil area. By arranging the pole ear in the empty foil area at the winding end of the battery cell body, it is prevented that the pole ear affects the flatness of the battery cell body, and it is also prevented that the pole ear itself and the empty foil area of ​​the pole piece occupy more battery cell space, thereby affecting the energy density of the battery cell.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of battery technology, and in particular to a battery cell, a battery and an electrical device. Background Art

[0002] The pole ear of a conventional wound battery cell is arranged at the head of the pole piece, so the pole ear needs to extend into the battery cell body, which reduces the flatness of the battery cell.

[0003] In the process of realizing the present application, the inventors found that in the prior art, since the tabs need to extend into the battery cell body, the tabs themselves, the tab protective glue, etc. will occupy more battery cell space, affecting the energy density of the battery cell.

[0004] Therefore, it is necessary to provide a battery cell to increase the space utilization of the battery cell and improve the energy density of the battery cell. Summary of the invention

[0005] The embodiments of the present application aim to provide a battery cell, a battery and an electrical device to increase the space utilization of the battery cell and improve the energy density of the battery cell.

[0006] In order to solve the above technical problems, the present invention provides a battery cell, including an electrode assembly and a shell for accommodating the electrode assembly, the shell including a accommodating portion and side wings extending from the accommodating portion, the electrode assembly including a battery cell body and a first electrode tab and a second electrode tab connected to the battery cell body, and the battery cell body is accommodated in the accommodating portion.

[0007] The battery cell body includes a first pole piece, a diaphragm, and a second pole piece which are stacked and wound, wherein along the winding direction of the battery cell body, the first pole piece includes a first empty foil area located at the winding end of the battery cell body, and the second pole piece includes a second empty foil area located at the winding end of the battery cell body, and the first empty foil area and the second empty foil area extend from the battery cell body to the side wing; the first end of the first pole ear is connected to the first empty foil area, and the first end of the second pole ear is connected to the second empty foil area.

[0008] The first pole ear and the second pole ear are connected to the empty foil area at the winding end of the battery body, so that the first pole ear and the second pole ear do not affect the overall flatness of the battery body. At the same time, it can also avoid the empty foil area of ​​the pole ear itself and the pole piece occupying more battery space and affecting the energy density of the battery.

[0009] In some embodiments, the first empty foil area and the second empty foil area are sandwiched between the side wings.

[0010] So that the first empty foil area and the second empty foil area are fixed to the side wings.

[0011] In some embodiments, the side wing is located on the side wall of the receiving portion, and the connection between the side wing and the receiving portion is a folded edge. The folded edge divides the first empty foil area into a first transition area and a first connection area, the first transition area is located in the receiving portion, the first connection area is located in the side wing, and the first electrode tab is located in the first connection area.

[0012] The first pole tab is located in the first connection area, which can prevent the first pole tab from occupying the space of the accommodation portion and improve the energy density of the battery cell.

[0013] In some embodiments, the second end of the first electrode tab extends from the first connection region from the side wing to outside the housing.

[0014] In some embodiments, the direction in which the first transition region extends toward the first connection region is the width direction of the battery cell body. The first electrode tab extends from the side wing to the outside of the housing along the width direction of the battery cell body.

[0015] In some embodiments, the first pole lug is a T-shaped pole lug, so that the first pole lug has a sufficient welding area to ensure that the first pole lug is firmly connected to the battery cell body.

[0016] In some embodiments, the first pole lug is a straight pole lug, and the width of the first pole lug is relatively wide, so as to increase the welding area of ​​the first pole lug and ensure that the first pole lug is firmly connected to the battery cell body.

[0017] In some embodiments, the direction in which the first transition zone extends toward the first connection zone is the width direction of the battery cell body, the direction perpendicular to the plane where the side wing is located is the thickness direction of the battery cell body, and the direction perpendicular to both the width direction of the battery cell body and the thickness direction of the battery cell body is the length direction of the battery cell body.

[0018] The second end of the first pole ear extends from the side wing to the outside of the shell along the length direction of the battery body.

[0019] In some embodiments, the first empty foil area and the second empty foil area are located on the same side of the battery cell body, or the first empty foil area and the second empty foil area are located on both sides of the battery cell body, respectively.

[0020] In some embodiments, the second end of the first pole lug and the second end of the second pole lug extend from the side wing to the housing in the same direction. Alternatively, the second end of the first pole lug and the second end of the second pole lug extend from the side wing to the housing in opposite directions.

[0021] In some embodiments, a first insulating sealant and a second insulating sealant are further included, wherein the first insulating sealant seals the connection between the first pole ear and the side wing, and the second insulating sealant seals the connection between the second pole ear and the side wing, and neither the first insulating sealant nor the second insulating sealant exceeds the folded edge.

[0022] The provision of the first insulating sealant and the second insulating sealant can prevent lithium deposition in the gaps of the battery cell during the charge and discharge process, thereby ensuring the safety of the battery cell and increasing the service life of the battery cell.

[0023] In addition, the first insulating sealant and the second insulating sealant do not exceed the folding edge in order to prevent the first insulating sealant or the second insulating sealant from increasing the thickness of the battery body and affecting the energy density of the battery.

[0024] In some embodiments, the shell is a packaging bag, and the packaging bag is an aluminum-plastic film.

[0025] In some embodiments, the packaging bag includes a first packaging bag and a second packaging bag, the first packaging bag is recessed from the middle to form a accommodating space, the battery cell body is placed in the accommodating space, the second packaging bag covers and closes the accommodating space, the accommodating space and the portion of the second packaging bag covering the accommodating space form the accommodating portion, the edge of the first packaging bag and the edge of the second packaging bag form the side wing, and hot melt sealing is used between the edge of the first packaging bag and the edge of the second packaging bag.

[0026] An embodiment of the present invention further provides a battery including the above-mentioned battery cell.

[0027] An embodiment of the present invention further provides an electrical device, comprising the above-mentioned battery and a load, wherein the load is used to supply power to the load. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0029] Figure 1 is a plan view schematic diagram of a battery cell provided by an embodiment of the present invention;

[0030] Figure 2 is a plan view of a battery cell provided by another embodiment of the present invention;

[0031] Figure 3 yes Figure 1A schematic diagram of the structure of a battery cell in which a tab extends along the width direction of the battery cell body;

[0032] Figure 4 yes Figure 1 The structure schematic diagram of the battery cell shown is that the electrode ear extends along the length direction of the battery cell body. DETAILED DESCRIPTION

[0033] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" / "installed on" another element, it can be directly on another element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to another element, or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "outer", "vertical", "horizontal", etc. used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0034] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0035] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] See also Figure 1, is a plan view of a battery cell 100 provided in an embodiment of the present invention. The battery cell 100 includes a shell 10 and an electrode assembly 20 . The electrode assembly 20 is accommodated in the shell 10 . The shell 10 includes a receiving portion 11 and a side wing 12 extending from the receiving portion 11, and the electrode assembly 20 includes a battery cell body and a first pole ear 24 and a second pole ear 25 connected to the battery cell body. The battery cell body is accommodated in the receiving portion 11, and the battery cell body includes a first pole sheet 21, a diaphragm 22, and a second pole sheet 23 that are stacked and wound, wherein along the winding direction of the battery cell body, the first pole sheet 21 includes a first empty foil area 211 located at the winding end of the battery cell body, and the second pole sheet 23 includes a second empty foil area 231 located at the winding end of the battery cell body, the first empty foil 211 and the second empty foil area 231 extend from the battery cell body to the side wing 12, the first end of the first pole ear 24 is connected to the first empty foil area 211, and the second pole ear 25 is connected to the second empty foil area 231.

[0037] The first pole tab 24 and the second pole tab 25 are connected to the empty foil area at the winding end of the battery cell body, so that the first pole tab and the second pole tab do not affect the overall flatness of the battery cell body.

[0038] It can be understood that the connection between the first electrode tab 24 and the first empty foil area 211 is welding, and the connection between the second electrode tab 25 and the second empty foil area 231 is welding.

[0039] It should be noted that the first pole piece 21 can be a positive pole piece, and the second pole piece 23 can be a negative pole piece, then the first pole ear 24 is a positive pole ear, and the second pole ear 25 is a negative pole ear. Of course, the first pole piece 21 can also be a negative pole piece, and the second pole piece 23 can also be a positive pole piece. This application does not make any present, as long as the polarities of the first pole piece and the second pole piece are opposite.

[0040] In an embodiment of the present invention, the shell 10 is a packaging bag. Specifically, the packaging bag includes a first packaging bag and a second packaging bag. The first packaging bag is recessed from the middle to form a accommodating space. The battery cell body is placed in the accommodating space. The second packaging bag covers and closes the accommodating space. The accommodating space and the portion of the second packaging bag covering the accommodating space form the accommodating portion 11. The edge of the first packaging bag and the edge of the second packaging bag form the side wing 12. Hot melt sealing is adopted between the edge of the first packaging bag and the edge of the second packaging bag, so that the first packaging bag seals the accommodating space. The first empty foil area 211 and the second empty foil area 231 are clamped between the side wing 12.

[0041] The packaging bag is an aluminum-plastic film.

[0042] The first empty foil area 211 and the second empty foil area 231 may be located on the same side of the battery cell body. Figure 1 As shown; the first empty foil area 211 and the second empty foil area 231 may also be located on both sides of the battery body, such as Figure 2 shown.

[0043] The side wing 12 is located on the side wall of the receiving portion 11, and the connection between the side wing 12 and the receiving portion 11 is a folding edge 13 (such as Figure 3 shown).

[0044] The folding edge 13 divides the first empty foil area 211 into a first transition area 2111 and a first connection area 2112, the first transition area 2111 is arranged in the accommodating portion 11, the first connection area 2112 is arranged in the side wing 12, the first pole ear 24 is located in the first connection area 2112, and the second end of the first pole ear 24 extends from the first connection area 2112 from the side wing 12 to the outside of the shell 10.

[0045] The folded edge 13 divides the second empty foil area 231 into a second transition area 2311 and a second connection area 2312. The second transition area 2311 is provided in the accommodating portion 11, the second connection area 2312 is provided in the side wing 12, and the second pole tab 25 is located in the second connection area 2312. The second end of the second pole tab 25 extends from the second connection area 2312 from the side wing 12 to the outside of the housing 10.

[0046] It can be understood that the first electrode tab 24 and the second electrode tab 25 can be folded onto the side wall of the accommodating portion 11 together with the side wing 12 .

[0047] In this article, the direction in which the first transition zone 2111 extends toward the first connection zone 2112 is defined as the width direction of the battery cell body, the direction perpendicular to the plane where the side wing is located is defined as the thickness direction of the battery cell body, and the direction perpendicular to both the width direction and the thickness direction of the battery cell body is defined as the length direction of the battery cell body.

[0048] By setting the first pole tab 24 in the first connection area 2112 and the second pole tab 25 in the second connection area 2312, the first pole tab 24 and the second pole tab 25 can only increase the width of the battery body without increasing the thickness of the battery body, thereby improving the energy density of the battery cell 100.

[0049] The second end of the first pole tab 24 and the second end of the second pole tab 25 may extend from the side wing 12 to the outside of the housing 10 along the length direction or the width direction of the battery cell body. The second end of the first pole tab 24 and the second end of the second pole tab 25 extend from the side wing 12 to the outside of the housing 10 in the same direction or in opposite directions. For example, the second end of the first pole tab 24 and the second end of the second pole tab 25 extend from the side wing 12 to the outside of the housing 10 in the same direction, and the second end of the first pole tab 24 and the second end of the second pole tab 25 extend from the side wing 12 to the outside of the housing 10 along the width direction of the battery cell body, as shown in FIG. Figure 3 Alternatively, the second end of the first pole tab 24 and the second end of the second pole tab 25 extend out of the housing from the side wing 12 in opposite directions, and the second end of the first pole tab 24 and the second end of the second pole tab 25 extend from the side wing 12 to the outside of the housing 10 along the length direction of the battery body, as shown in FIG. Figure 4 shown.

[0050] Of course, when the second end of the first pole tab 24 and the second end of the second pole tab 25 extend from the side wing 12 to the shell 10 in the same direction, the second end of the first pole tab 24 and the second end of the second pole tab 25 may also extend from the side wing 12 to the outside of the shell 10 along the length direction of the battery body. Alternatively, when the second end of the first pole tab 24 and the second end of the second pole tab 25 extend from the side wing 12 to the outside of the shell 10 in opposite directions, the second end of the first pole tab 24 and the second end of the second pole tab 25 may also extend from the side wing 12 to the outside of the shell 10 along the width direction of the battery body.

[0051] When the first pole lug 24 or the second pole lug 25 extends out of the housing 10 along the width direction of the battery cell body, the first pole lug 24 or the second pole lug 25 may be a T-shaped pole lug to ensure that the first pole lug 24 and the second pole lug 25 can be firmly connected to the battery cell body. It can be understood that in the above manner, the first pole lug 24 and the second pole lug 25 may not be T-shaped pole lugs, as long as the first pole lug 24 and the second pole lug 25 have sufficient welding area. For example, the first pole lug 24 and the second pole lug are both straight pole lugs, and the width of the straight pole lug is relatively wide, so as to ensure that the first pole lug 24 has a larger contact area with the first empty foil area 211, and facilitate the welding of the first pole lug 24 and the first empty foil area 211. The same is true for the second pole lug 25, which will not be repeated here.

[0052] In some embodiments, the battery cell 100 further includes a first insulating sealant 30 and a second insulating sealant 40 , wherein the first insulating sealant 30 is used to seal the connection between the first pole tab 24 and the side wing 12 , and the second insulating sealant 40 is used to seal the connection between the second pole tab 25 and the side wing 12 .

[0053] like Figure 4 As shown, when the second end of the first pole ear 24 and the second end of the second pole ear 25 extend from the side wing 12 to the outside of the shell 10 along the length direction of the battery body, the first insulating sealant 20 and the second insulating sealant 40 do not exceed the folding edge 13, that is, there is a gap between the first insulating sealant 30 and the second insulating sealant 40 and the folding edge 13 to avoid the first insulating sealant 20 and the second insulating sealant 40 increasing the thickness of the battery body and affecting the energy density of the battery 100.

[0054] An embodiment of the present invention further provides a battery, comprising the battery cell 100 described above.

[0055] An embodiment of the present invention further provides an electrical device, comprising the above-mentioned battery and a load, wherein the battery is used to supply power to the load.

[0056] The electrical equipment may be an electric car, a drone, a sweeping robot, a mobile phone, a tablet, etc.

[0057] An embodiment of the present invention provides a battery cell, a battery, and an electrical device, by arranging the pole ear in the empty foil area at the winding end of the battery cell body, so as to avoid the pole ear affecting the flatness of the battery cell body, and also to avoid the pole ear itself and the empty foil area of ​​the pole piece occupying more battery cell space and affecting the energy density of the battery cell.

[0058] It should be noted that the preferred embodiments of the present invention are given in the specification and drawings of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. These embodiments are not intended to be additional limitations on the content of the present invention. The purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. In addition, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all considered to be within the scope of the present invention; further, for ordinary technicians in this field, they can be improved or transformed according to the above description, and all these improvements and transformations should belong to the scope of protection of the claims attached to the present invention.

Claims

1. A battery cell, comprising an electrode assembly and a shell for accommodating the electrode assembly, characterized in that: The shell includes a receiving portion and a wing extending from the receiving portion, the electrode assembly includes a battery body and a first electrode tab and a second electrode tab connected to the battery body, and the battery body is received in the receiving portion; The battery cell body comprises a first pole piece, a diaphragm and a second pole piece which are stacked and wound, wherein along the winding direction of the battery cell body, the first pole piece comprises a first empty foil area located at the winding end of the battery cell body, and the second pole piece comprises a second empty foil area located at the winding end of the battery cell body, and the first empty foil area and the second empty foil area extend from the battery cell body to the side wing; The first end of the first electrode tab is connected to the first empty foil area, and the first end of the second electrode tab is connected to the second empty foil area; The first empty foil area and the second empty foil area are sandwiched between the side wings; The shell is a packaging bag, which includes a first packaging bag and a second packaging bag. The first packaging bag is recessed in the middle to form a accommodating space, the battery cell body is placed in the accommodating space, the second packaging bag covers and closes the accommodating space, the accommodating space and the part of the second packaging bag covering the accommodating space form the accommodating portion, the edge of the first packaging bag and the edge of the second packaging bag form the side wing, and the edge of the first packaging bag and the edge of the second packaging bag are hot-melt sealed.

2. The battery cell according to claim 1, characterized in that: The side wing is located on the side wall of the accommodating portion, and the connection between the side wing and the accommodating portion is a folded edge; The folded edge divides the first empty foil area into a first transition area and a first connection area, the first transition area is provided in the receiving portion, the first connection area is provided in the side wing, and the first electrode tab is located in the first connection area.

3. The battery cell according to claim 2, characterized in that: The second end of the first pole tab extends from the first connection area through the side wing to the outside of the housing.

4. The battery cell according to claim 3, characterized in that: The direction in which the first transition area extends toward the first connection area is the width direction of the battery cell body; The first pole tab extends from the side wing to the outside of the shell along the width direction of the battery body.

5. The battery cell according to claim 4, characterized in that: The first pole lug is a T-shaped pole lug.

6. The battery cell according to claim 4, characterized in that: The first pole tab is a straight pole tab, and the first pole tab has a relatively wide width.

7. The battery cell according to claim 3, characterized in that: The direction in which the first transition area extends toward the first connection area is the width direction of the battery cell body, the direction perpendicular to the plane where the side wing is located is the thickness direction of the battery cell body, and the direction perpendicular to both the width direction and the thickness direction of the battery cell body is the length direction of the battery cell body; The second end of the first pole ear extends from the side wing to the outside of the shell along the length direction of the battery body.

8. The battery cell according to any one of claims 3 to 7, characterized in that: The first empty foil area and the second empty foil area are located on the same side of the battery cell body, or the first empty foil area and the second empty foil area are located on both sides of the battery cell body, respectively.

9. The battery cell according to any one of claims 3 to 7, characterized in that: The second end of the first pole lug and the second end of the second pole lug extend out of the housing from the side wing in the same direction. or, The second end of the first pole lug and the second end of the second pole lug extend out of the housing from the side wing in opposite directions.

10. The battery cell according to claim 3, characterized in that: It also includes a first insulating sealant and a second insulating sealant, wherein the first insulating sealant seals the connection between the first pole ear and the side wing, and the second insulating sealant seals the connection between the second pole ear and the side wing, and both the first insulating sealant and the second insulating sealant do not exceed the folded edge.

11. The battery cell according to claim 1, characterized in that: The shell is a packaging bag, and the packaging bag is an aluminum-plastic film.

12. A battery, characterized in that: Comprising the battery cell as claimed in any one of claims 1 to 11.

13. An electrical equipment, characterized in that: comprising the battery of claim 12; and A load, wherein the battery is used to supply power to the load.

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