Pole piece, pole core and battery

Abstract

The utility model belongs to the technical field of batteries, and particularly relates to a pole piece, a pole core and a battery, the pole piece comprises a body, a pole lug and a protective layer, the body comprises a main body part and a connecting part, the main body part is in a long strip shape, the connecting part is connected to the long edge of the main body part, a notch is formed in the connecting part, and the protective layer is arranged in the notch. One end of the pole lug extends into the notch and is connected to the long edge of the main body part, the two side surfaces of the main body part in the thickness direction are both coated with active substances, the two side surfaces of the connecting part in the thickness direction are both provided with the protective layers, and the protective layers can separate the connecting part from the diaphragm of the pole core. The protective layer not only can separate the connecting part from the diaphragm of the pole core to prevent burrs generated in the die cutting process from being in contact with the diaphragm so as to prevent the burrs from puncturing the diaphragm and improve the safety of the pole core, but also can prevent burrs from being generated on the die cutting edge of the body in the die cutting process.

Description

Technical Field

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

[0002] An existing battery includes a shell and a pole core installed in the shell. The pole core includes a diaphragm and multiple pole pieces. When the pole piece is produced, one end of the foil needs to be die-cut to form a pole ear. The remaining part of the foil serves as the pole piece body connected to the pole ear. Both sides of the pole piece body in the thickness direction are coated with active material. The multiple pole pieces of the battery are stacked, and the pole piece bodies of any two adjacent pole pieces are separated by a diaphragm. Then, the pole ears on each pole piece are bent to form a pole ear bundle, and hard pole ears are connected to the pole ear bundle. Finally, the pole core is formed by winding or lamination.

[0003] In existing batteries, burrs are easily left on the electrode pieces after die-cutting, and the burrs can easily pierce the diaphragm, resulting in poor safety. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that, in view of the problem that burrs are easily left on the pole pieces after die-cutting in existing batteries, and the burrs are easy to pierce the diaphragm, resulting in poor safety, a pole piece, a pole core and a battery are provided.

[0005] To solve the above technical problems, on the one hand, the embodiment of the present invention provides a pole piece, comprising a body, a pole ear and a protective layer, wherein the body comprises a main body portion and a connecting portion, the main body portion is in the shape of an elongated strip, the connecting portion is connected to the long side of the main body portion, a notch is provided on the connecting portion, one end of the pole ear extends into the notch and is connected to the long side of the main body portion, and both sides of the main body portion in the thickness direction are coated with an active material;

[0006] The protective layer is provided on both sides of the connecting portion in the thickness direction, and the protective layer can separate the connecting portion from the diaphragm of the pole core.

[0007] Optionally, the protective layer is a flexible film.

[0008] Optionally, the protective layer is an insulating coating coated on both side surfaces of the connecting portion in a thickness direction.

[0009] Optionally, the insulating coating is a ceramic coating.

[0010] Optionally, the protective layer provided on one side surface of the connecting portion in the thickness direction is a flexible film, and the protective layer provided on the other side surface of the connecting portion in the thickness direction is an insulating coating.

[0011] Optionally, the protective layer is provided on both sides of the tab in the thickness direction.

[0012] Optionally, the width of the connecting portion is W0, 0.1 mm ≤ W0 ≤ 5 mm.

[0013] Optionally, the width of the notch is W1, 1mm≤W1≤50mm;

[0014] The width of the tab is smaller than the width of the notch. Gaps are provided on both sides of the tab and the notch in a width direction. The width of the gap is W2, and 0.5 mm ≤ W2 < 25 mm.

[0015] Optionally, a plurality of the tabs are provided, a plurality of the notches are provided, the plurality of notches are arranged at intervals along the length direction of the connecting portion, and the plurality of tabs are arranged in one-to-one correspondence with the plurality of notches.

[0016] According to the pole piece of the embodiment of the present invention, compared with the prior art, protective layers are provided on both sides of the thickness direction of the connecting portion. The protective layers can not only separate the connecting portion and the diaphragm of the pole core, avoiding the burrs generated during the die-cutting process from contacting the diaphragm, thereby avoiding the burrs from piercing the diaphragm and improving the safety of the pole core, but also can avoid the generation of burrs on the die-cutting edge of the main body during the die-cutting process. In addition, the setting of the notch can also provide an accommodation space for the subsequent folding of the pole ear of the pole core, avoiding occupying the width of the main body, which is beneficial to improving the energy density of the battery.

[0017] On the other hand, an embodiment of the present invention provides a pole core, including a positive pole sheet, a negative pole sheet and a separator, wherein the positive pole sheet and the negative pole sheet are the above-mentioned pole sheets, both sides of the main body of the positive pole sheet in the thickness direction are coated with positive pole active material, and both sides of the main body of the negative pole sheet in the thickness direction are coated with negative pole active material, and the separator is sandwiched between the adjacent positive pole sheet and negative pole sheet.

[0018] On the other hand, an embodiment of the present invention provides a battery, comprising a housing and the above-mentioned pole core, wherein the pole core is arranged in the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic structural diagram of a pole piece provided in one embodiment of the present utility model.

[0020] The figures in the specification are as follows: 1. body; 11. main body; 12. active material; 13. connecting part; 14. notch; 2. tab; 3. protective layer; 31. ceramic coating. DETAILED DESCRIPTION

[0021] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] like Figure 1 As shown, an embodiment of the present invention provides a pole piece, including a body 1, a pole ear 2 and a protective layer 3, the body 1 includes a main body 11 and a connecting portion 13, the main body 11 is a long strip, the connecting portion 13 is connected to one of the long sides of the main body 11, a notch 14 is provided on the connecting portion 13, one end of the pole ear 2 extends into the notch 14 and is connected to one of the long sides of the main body 11, and active material 12 is coated on both sides of the main body 11 in the thickness direction.

[0023] The protective layer 3 is provided on both sides of the connecting portion 13 in the thickness direction. The protective layer 3 can separate the connecting portion 13 from the diaphragm of the electrode core.

[0024] Specifically, during the production process, the active substance 12 can be coated on the foil and the protective layer 3 can be set, and then the foil can be die-cut. The protective layer 3 can be set on the foil first to protect the foil during the die-cutting process and reduce the burrs on the die-cutting edges. The foil can also be die-cut first, and then the active substance 12 can be coated on the foil and the protective layer 3 can be set. The protective layer 3 can be set later to separate the connecting part 13 and the diaphragm of the pole core, avoiding contact between the burrs and the diaphragm, thereby avoiding the burrs piercing the diaphragm and improving the safety of the pole core.

[0025] In one embodiment, the protective layer 3 is an insulating coating applied to both sides of the connecting portion 13 in the thickness direction. The insulating coating is a ceramic coating 31. The insulating coating is easy to apply and simple to operate, which helps reduce the difficulty of construction. The ceramic coating 31 is strong and can effectively protect the connecting portion 13, thereby improving the protective strength.

[0026] In one embodiment, the protective layer 3 is provided on both sides of the tab 2 in the thickness direction.

[0027] Specifically, a protective layer 3 is provided on both sides of the pole tab 2 in the thickness direction. The protective layer 3 is an insulating coating formed by a ceramic coating 31, which can form a protective layer on the pole tab 2 to prevent burrs generated on the edge of the pole tab 2 from piercing the diaphragm of the pole core, thereby further improving the safety of the pole core.

[0028] In one embodiment, the connecting portion 13 is square, the width of the connecting portion 13 is W0, 0.1mm≤W0≤5mm, the notch 14 is square, the width of the notch 14 is W1, 1mm≤W1≤50mm, the width of the tab 2 is smaller than the width of the notch 14, and a gap is provided on both sides of the tab 2 and the notch 14 in the width direction, the width of the gap is W2, 0.5mm≤W2<25mm.

[0029] Specifically, the connecting portion 13 is square, and the notch 14 is provided on the connecting portion 13. The notch 14 is provided through the connecting portion 13 along the width direction of the connecting portion 13. The width of the notch 14 is W1, 1mm≤W1≤50mm, and the width of the connecting portion 13 (depth of the notch 14) is W0, 0.1mm≤W0≤5mm, thereby providing sufficient accommodation space for the subsequent folding ear 2 process.

[0030] In one embodiment, there are multiple tabs 2 and multiple notches 14 , and the multiple notches 14 are arranged at intervals along the length direction of the connecting portion 13 . The multiple tabs 2 and the multiple notches 14 are arranged in a one-to-one correspondence.

[0031] Specifically, there are multiple tabs 2 and multiple notches 14, and the multiple notches 14 are spaced apart on the edge of the length direction of the connecting portion 13. The number of tabs 2 is consistent with the number of notches 14, and the tabs 2 correspond to the notches 14 one by one. The tabs 2 pass through the notches 14 and are connected to one side of the length direction of the main body. The provision of multiple tabs 2 can provide multiple external ports for the battery, thereby improving the charging efficiency and discharging efficiency of the battery and meeting the requirements of fast charging and discharging.

[0032] In the production process of the pole piece of the embodiment of the present invention, the active material 12 can be first coated on the foil and the protective layer 3 can be set, and then the foil can be die-cut. The protective layer 3 can be first set on the foil to protect the foil during the die-cutting process and reduce burrs on the die-cutting edges. The foil can also be die-cut first, and then the active material 12 can be coated on the foil and the protective layer 3 can be set. The protective layer 3 can be set later to separate the connecting portion 13 and the diaphragm of the pole core to prevent the burrs from contacting the diaphragm, thereby preventing the burrs from puncturing the diaphragm.

[0033] According to the pole piece of the embodiment of the present invention, a protective layer 3 is provided on both sides of the connecting portion 13 in the thickness direction. The protective layer 3 can not only separate the connecting portion 13 and the diaphragm of the pole core, preventing the burrs generated during the die-cutting process from contacting the diaphragm, thereby preventing the burrs from piercing the diaphragm and improving the safety of the pole core, but also can prevent burrs from being generated on the die-cutting edge of the main body 1 during the die-cutting process.

[0034] In addition, one embodiment of the present invention provides a pole core, including a positive pole sheet, a negative pole sheet and a separator, the positive pole sheet and the negative pole sheet are the above-mentioned pole sheets, both sides of the thickness direction of the main body 11 of the positive pole sheet are coated with positive active material, and both sides of the thickness direction of the main body 11 of the negative pole sheet are coated with negative active material, and the separator is sandwiched between the adjacent positive pole sheet and negative pole sheet.

[0035] In addition, an embodiment of the present invention provides a battery, comprising a housing and the above-mentioned pole core, wherein the pole core is disposed in the housing.

[0036] In other embodiments, the protective layer 3 is a flexible film made of a strong insulating material, which can effectively protect against burrs. The flexible film is adhered to the connecting portion 13 .

[0037] In other embodiments, the protective layer 3 provided on one side surface of the connecting portion 13 in the thickness direction is a flexible film, and the protective layer 3 provided on the other side surface of the connecting portion 13 in the thickness direction is an insulating coating, which is a ceramic coating 31. The flexible film is made of an insulating material with relatively high strength and can provide effective protection against burrs. The flexible film is bonded to the connecting portion 13.

[0038] In other embodiments, there are two connecting parts 13, which are respectively connected to the long sides of the main body 11 on both sides. A notch 14 is provided on the connecting part 13, and a pole ear 2 is provided on both sides of the width direction of the main body 11. One end of the pole ear 2 extends into the notch 14 and is connected to the long side of the main body 11.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pole piece, characterized in that: The invention comprises a body (1), a tab (2) and a protective layer (3), wherein the body (1) comprises a main body portion (11) and a connecting portion (13), wherein the main body portion (11) is in the shape of an elongated strip, the connecting portion (13) is connected to the long side of the main body portion (11), a notch (14) is provided on the connecting portion (13), one end of the tab (2) extends into the notch (14) and is connected to the long side of the main body portion (11), and active material (12) is coated on both sides of the main body portion (11) in the thickness direction; The protective layer (3) is provided on both sides of the connecting portion (13) in the thickness direction, and the protective layer (3) can separate the connecting portion (13) from the diaphragm of the pole core.

2. The pole piece according to claim 1, characterized in that: The protective layer (3) is a flexible film.

3. The pole piece according to claim 1, characterized in that: The protective layer (3) is an insulating coating applied on both side surfaces of the connecting portion (13) in the thickness direction.

4. The pole piece according to claim 3, characterized in that: The insulating coating is a ceramic coating (31).

5. The pole piece according to claim 1, characterized in that: The protective layer (3) provided on one side of the connecting portion (13) in the thickness direction is a flexible film, and the protective layer (3) provided on the other side of the connecting portion (13) in the thickness direction is an insulating coating.

6. The pole piece according to claim 1, characterized in that: The protective layer (3) is provided on both sides of the tab (2) in the thickness direction.

7. The pole piece according to claim 1, characterized in that: The width of the connecting portion (13) is W0, 0.1 mm ≤ W0 ≤ 5 mm.

8. The pole piece according to claim 1, characterized in that: The width of the notch (14) is W1, 1mm≤W1≤50mm; The width of the tab (2) is smaller than the width of the notch (14), and gaps are provided on both sides of the tab (2) and the notch (14) in the width direction, with the width of the gap being W2, 0.5 mm ≤ W2 < 25 mm.

9. The pole piece according to claim 1, characterized in that: A plurality of the tabs (2) are provided, and a plurality of the notches (14) are provided. The plurality of notches (14) are arranged at intervals along the length direction of the connecting portion (13), and the plurality of tabs (2) and the plurality of notches (14) are arranged in a one-to-one correspondence.

10. A pole core, characterized in that: The invention comprises a positive electrode sheet, a negative electrode sheet and a separator, wherein the positive electrode sheet and the negative electrode sheet are the electrode sheets according to any one of claims 1 to 9, both sides of the main body (11) of the positive electrode sheet in the thickness direction are coated with positive electrode active material, and both sides of the main body (11) of the negative electrode sheet in the thickness direction are coated with negative electrode active material, and the separator is sandwiched between the adjacent positive electrode sheet and negative electrode sheet.

11. A battery, characterized in that: It comprises a shell and the pole core according to claim 10, wherein the pole core is arranged in the shell.

Images