Battery cell and lithium battery

Abstract

The utility model discloses a battery cell and lithium battery, the battery cell includes main part, tab and first gummed paper, the main part has first end face and second end face, the tab is provided on the first end face, the first gummed paper includes first covering part and two second covering part, the first covering part is provided with a first end face and a second end face, and the second covering part is provided with a second end face. The first covering part is located between the two second covering parts, the first covering part is attached to the first end face, and the two second covering parts are attached to the positions, on the two sides of the first end face, of the surface of the main body part; a slot position hole is formed in the first covering part, and the tab penetrates through the slot position hole. The lithium battery disclosed by the utility model comprises the battery cell. According to the utility model, the first gummed paper and the second gummed paper are respectively adhered to the two ends of the battery cell main body part, namely the first end surface and the second end surface, so that the problem of poor contact between the pole pieces caused by loose adhesion between the pole pieces on the outer side due to lack of binding force on the outer side of the existing battery cell is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, and in particular mainly to a battery core and a lithium battery. Background Art

[0002] The cell of a lithium battery is made of positive electrode sheets, negative electrode sheets and diaphragms through a lamination process or a winding process. The cells after lamination or winding are bare cells. The electrodes closer to the center of the bare cell are tightly wrapped, so they are subject to greater force and fit more tightly to each other. The electrodes closer to the outside or outer ring of the bare cell are relatively loosely fitted to each other due to the lack of external binding force. At the same time, the binding force between the electrodes at the head and tail of the cell is smaller than that of the electrodes in the middle of the cell, so the electrodes at the head and tail of the cell fit more loosely.

[0003] In addition, electrolyte needs to be added during the battery cell packaging process. The electrolyte infiltrates between the electrode and the diaphragm of the bare battery cell, which further deteriorates the bonding effect between the electrode near the outside or outer circle of the bare battery cell. During long-term cyclic use, poor contact between the positive and negative electrode sheets will lead to black spots and lithium precipitation inside the battery cell, reducing the service life of the product.

[0004] In view of this, it is necessary to improve the cell structure of existing lithium batteries. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model provides a battery cell and a lithium battery to solve the problem of poor contact between pole pieces caused by lack of binding force on the outside and loose fitting of the outer pole pieces in the prior art battery cells, thereby increasing the service life of the battery cell.

[0006] The utility model discloses a battery cell, comprising a main body, a pole ear and a first adhesive tape, wherein the main body has a first end face and a second end face, the pole ear is arranged on the first end face, the first adhesive tape comprises a first covering portion and two second covering portions, the first covering portion is located between the two second covering portions, the first covering portion is attached to the first end face, and the two second covering portions are attached to the surface of the main body on both sides of the first end face; a slot hole is provided on the first covering portion, and the pole ear passes through the slot hole.

[0007] Preferably, the battery cell includes a second adhesive tape, the second adhesive tape includes a third covering part and two fourth covering parts, the third covering part is located between the two fourth covering parts, the fourth covering part is attached to the second end face, and the two fourth covering parts are attached to the surface of the main body on both sides of the second end face.

[0008] Preferably, the first covering portion is provided with a plurality of first liquid-permeable holes, and the third covering portion is provided with a plurality of second liquid-permeable holes.

[0009] Preferably, the width of the first covering portion is not less than the thickness of the main body portion, and the width of the third covering portion is not less than the thickness of the main body portion.

[0010] Preferably, two pole tabs are provided, two slot holes are opened, and the two pole tabs pass through the two slot holes respectively.

[0011] Preferably, the first adhesive tape and the second adhesive tape both include a substrate and an adhesive layer, the adhesive layer covers the surface of the substrate, and the first adhesive tape and the second adhesive tape both contact the main body through the adhesive layer.

[0012] Preferably, the substrate comprises one or more of thermoplastic polyester, polyethylene, polypropylene, and polyvinyl chloride; and the adhesive layer comprises one or more of acrylic resin, polycarbonate, polyurethane, and rubber.

[0013] Preferably, the width of the first adhesive tape and the second adhesive tape is between 6 mm and 80 mm, and the thickness is between 6 um and 80 um.

[0014] Preferably, the slot hole has a length between 3 mm and 20 mm, and a width between 10 um and 200 um.

[0015] The utility model discloses a lithium battery, comprising any one of the above-mentioned battery cells.

[0016] The beneficial effects of the utility model are:

[0017] By affixing the first adhesive tape and the second adhesive tape to the two ends of the battery cell body, i.e., the first end face and the second end face, respectively, the two adhesive tapes generate a preset tensioning force between the two outer side faces of the battery cell body, so that the first adhesive tape and the second adhesive tape can generate a binding force on the outer side of the battery cell body, so that the pole pieces on the outer side of the battery cell body can be more closely attached, avoiding the phenomenon of insufficient ion exchange capacity caused by poor contact between the pole pieces, thereby solving the lithium plating problem;

[0018] In addition, the first liquid-permeable hole formed on the first adhesive tape and the second liquid-permeable hole formed on the second adhesive tape are both conducive to the penetration of electrolyte, thereby providing a binding force for the battery cell body and improving the infiltration effect of the electrolyte.

[0019] Therefore, the utility model solves the problem of poor contact between pole pieces caused by lack of binding force on the outside of the existing battery core and loose fitting of the outer pole pieces, thereby increasing the service life of the battery core. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 It is a schematic diagram of the overall structure of the battery cell of the utility model, from a first viewing angle;

[0022] Figure 2 This is a schematic diagram of the overall structure of the battery cell of the present invention, from a second viewing angle.

[0023] Explanation of the reference numerals: 1. Main body; 101. First end face; 102. Second end face; 2. Tab; 3. First adhesive tape; 31. First covering portion; 311. Slot hole; 312. First liquid-permeable hole; 32. Second covering portion; 4. Second adhesive tape; 41. Third covering portion; 411. Second liquid-permeable hole; 42. Fourth covering portion. DETAILED DESCRIPTION

[0024] In order to further understand the content, features and effects of the utility model, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0025] Reference Figure 1 and Figure 2 , is a battery cell disclosed in the utility model, comprising a main body 1, a pole ear 2, a first adhesive tape 3 and a second adhesive tape 4, wherein the main body 1 comprises a positive electrode sheet, a negative electrode sheet and a separator, the three of which are stacked or wound on each other to form a main body 1 with a rectangular flat structure; the two opposite faces of the main body 1 in the length direction are a first end face 101 and a second end face 102, and the thickness of the main body 1 is the width of the first end face 101 or the second end face 102; the pole ear 2 is a metal long sheet structure, and two pole ears 2 are provided, the two pole ears 2 are respectively a positive pole ear 2 and a negative pole ear 2, and the two pole ears 2 are both installed on the first end face 101 and extend from the first end face 101 to the outside of the main body 1.

[0026] Reference Figure 1 and Figure 2The first adhesive tape 3 is a rectangular structure. The first adhesive tape 3 has a length and a width. The first adhesive tape 3 includes three mutually parallel rectangular areas. The three rectangular areas are divided along the length direction of the first adhesive tape 3, including a first covering portion 31 and two second covering portions 32. The first covering portion 31 is located between the two second covering portions 32. The width of the first covering portion 31 is not less than the thickness of the main body 1. The first covering portion 31 is attached to the first end surface 101, and the two second covering portions 32 are attached to the first end surface 101 respectively. 1; the first covering portion 31 is provided with two slot holes 311, the slot holes 311 are rectangular through holes, and the two tabs 2 respectively pass through the two slot holes 311 to extend to the other side of the first adhesive tape 3. In addition, the first covering portion 31 is also provided with a plurality of first liquid-permeable holes 312, which are densely distributed on the first covering portion 31, and are through holes. When the battery cell package is filled with electrolyte, the first liquid-permeable holes 312 are conducive to the infiltration of the electrolyte.

[0027] Reference Figure 1 and Figure 2 The second adhesive tape 4 is a rectangular structure. The second adhesive tape 4 has a length and a width. The width of the second adhesive tape 4 is smaller than the width of the main body 1. The second adhesive tape 4 includes three mutually parallel rectangular areas. The three rectangular areas are divided along the length direction of the second adhesive tape 4, including a third covering portion 41 and two fourth covering portions 42. The third covering portion 41 is located between the two fourth covering portions 42. The width of the third covering portion 41 is not less than the thickness of the main body 1; the third covering portion 41 is attached to the second end surface 102, and the two fourth covering portions 42 are respectively attached to the surface of the main body 1 on both sides of the second end surface 102; a plurality of second liquid-permeable holes 411 are opened on the third covering portion 41, and the plurality of second liquid-permeable holes 411 are densely distributed on the third covering portion 41. The second liquid-permeable holes 411 are through holes. When the battery cell is filled with electrolyte, the second liquid-permeable holes 411 are conducive to the infiltration of the electrolyte.

[0028] Reference Figure 1 and Figure 2 , the first adhesive tape 3 and the second adhesive tape 4 both include a substrate and an adhesive layer, the adhesive layer covers one side surface of the substrate, the substrate includes one or more of thermoplastic polyester, polyethylene, polypropylene, polyvinyl chloride, and the adhesive layer includes one or more of acrylic resin, polycarbonate, polyurethane, and rubber; the first adhesive tape 3 and the second adhesive tape 4 are both in contact with the main body 1 of the battery cell through the adhesive layer. The first adhesive tape 3 can form a pre-set tension between the two side surfaces of the main body 1 of the battery cell through its two second covering parts 32, and similarly, the second adhesive tape 4 can also form a pre-set tension between the two side surfaces of the main body 1 of the battery cell through its two fourth covering parts 42, so that the first adhesive tape 3 and the second adhesive tape 4 can jointly generate a binding force on the main body 1 of the battery cell, so that the pole pieces on the outside of the main body 1 of the battery cell fit more closely to each other.

[0029] Reference Figure 1 and Figure 2 Specifically, the width of the first adhesive tape 3 and the second adhesive tape 4 is between 6mm and 80mm, and the thickness is between 6um and 80um. The length of the second adhesive tape 4 can be freely set according to the length of the battery cell; the length of the slot hole 311 on the first adhesive tape 3 is between 3mm and 20mm, and the width is between 10um and 200um.

[0030] The utility model discloses a lithium battery, comprising the above-mentioned battery core.

[0031] The implementation principle and beneficial effect of the utility model are that by sticking the first adhesive tape 3 and the second adhesive tape 4 on the two ends of the battery cell main body 1, namely the first end face 101 and the second end face 102 respectively, the two adhesive tapes generate a preset tensioning force between the two outer side faces of the battery cell main body 1, so that the first adhesive tape 3 and the second adhesive tape 4 can generate a binding force on the outer side of the battery cell main body 1, so that the outer pole pieces of the battery cell main body 1 can be more closely fitted, avoiding the phenomenon of insufficient ion exchange capacity caused by poor contact between the pole pieces, thereby solving the lithium plating problem; therefore, the utility model solves the problem of poor contact between the pole pieces of the existing battery cells due to lack of binding force on the outer side and loose fitting of the outer pole pieces, thereby improving the service life of the battery cells.

[0032] The above is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A battery cell, characterized in that: The invention comprises a main body (1), a pole ear (2) and a first adhesive tape (3); the main body (1) has a first end face (101) and a second end face (102); the pole ear (2) is arranged on the first end face (101); the first adhesive tape (3) comprises a first covering part (31) and two second covering parts (32); the first covering part (31) is located between the two second covering parts (32); the first covering part (31) is attached to the first end face (101); the two second covering parts (32) are attached to the surface of the main body (1) on both sides of the first end face (101); a slot hole (311) is arranged on the first covering part (31); the pole ear (2) passes through the slot hole (311).

2. The battery cell according to claim 1, characterized in that: The battery cell comprises a second adhesive tape (4), the second adhesive tape (4) comprises a third covering portion (41) and two fourth covering portions (42), the third covering portion (41) is located between the two fourth covering portions (42), the fourth covering portion (42) is attached to the second end surface (102), and the two fourth covering portions (42) are attached to the surface of the main body (1) on both sides of the second end surface (102).

3. The battery cell according to claim 2, characterized in that: The first covering portion (31) is provided with a plurality of first liquid-permeable holes (312), and the third covering portion (41) is provided with a plurality of second liquid-permeable holes (411).

4. The battery cell according to claim 2, characterized in that: The width of the first covering portion (31) is not less than the thickness of the main body portion (1), and the width of the third covering portion (41) is not less than the thickness of the main body portion (1).

5. The battery cell according to any one of claims 1 to 4, characterized in that: Two pole lugs (2) are provided, two slot holes (311) are opened, and the two pole lugs (2) pass through the two slot holes (311) respectively.

6. The battery cell according to any one of claims 2 to 4, characterized in that: The first adhesive tape (3) and the second adhesive tape (4) both comprise a substrate and an adhesive layer, wherein the adhesive layer covers the surface of the substrate, and the first adhesive tape (3) and the second adhesive tape (4) both contact the main body (1) via the adhesive layer.

7. The battery cell according to claim 6, characterized in that: The substrate includes one of thermoplastic polyester, polyethylene, polypropylene and polyvinyl chloride; the adhesive layer includes one of acrylic resin, polycarbonate, polyurethane and rubber.

8. The battery cell according to any one of claims 2 to 4, characterized in that: The width of the first adhesive tape (3) and the second adhesive tape (4) is between 6 mm and 80 mm, and the thickness is between 6 um and 80 um.

9. The battery cell according to any one of claims 1 to 4, characterized in that: The slot hole (311) has a length between 3 mm and 20 mm, and a width between 10 um and 200 um.

10. A lithium battery, characterized in that: A battery cell comprising any one of claims 1 to 9.

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