Current collector, pole piece, pole core and battery

Abstract

The utility model belongs to the technical field of batteries, and particularly relates to a current collector, a pole piece, a pole core and a battery, the current collector is divided into a main body part and a pole lug part, two side surfaces of the main body part in the thickness direction are suitable for being provided with active material layers, the main body part is provided with a first side edge, and the pole lug part comprises a connecting area, a first folding area and a second folding area, the connecting area is connected to the first side edge, the connecting area is provided with a first side edge and a second side edge, the first folding area is connected to the first side edge, and the second folding area is connected to the second side edge. The first folding areas of the current collectors in the pole pieces with the same polarity in the pole core are folded towards the outer side of the pole piece on one side of the pole pieces with the same polarity and are welded with the surface of the pole piece, and the second folding areas of the current collectors in the pole pieces with the same polarity in the pole core are folded towards the outer side of the pole piece on the other side and are welded with the surface of the outer side of the pole piece with the same polarity; the current collectors of the pole pieces with the same polarity in the pole core are connected together, and the installation steps are simplified.

Description

Technical Field

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

[0002] The main function of the current collector is to collect the current generated by the active substances of each pole piece in the battery cell and output it to the external circuit.

[0003] An existing pole core structure includes a plurality of pole pieces. Each pole piece includes a current collector and active substances arranged on both sides of the current collector. Different pole pieces are stacked together. The current collector includes a polymer material base film in the middle part, and metal layers are plated on both the upper and lower surfaces of the base film. The metal layers on both sides of the same current collector need to be electrically connected through a conductive sheet, and finally the current collectors of each pole piece are welded together to form the pole ear bundle of the pole core.

[0004] For the existing pole core structure, it is necessary to weld a conductive sheet on each current collector, which is troublesome to install and has low working efficiency. Summary of the Invention

[0005] The technical problem to be solved by the utility model is: aiming at the problem that the existing pole core structure needs to weld a conductive sheet on each current collector and is troublesome to install, a current collector, a pole piece, a pole core and a battery are provided.

[0006] To solve the above technical problem, on the one hand, an embodiment of the utility model provides a current collector, which includes a base film, a first metal layer and a second metal layer. The first metal layer is arranged on one surface of the base film in the thickness direction, and the second metal layer is arranged on the other surface of the base film in the thickness direction. The current collector is divided into a main body part and a pole ear part. Both surfaces of the main body part in the thickness direction are suitable for arranging active substance layers;

[0007] The main body part has a first side edge. The pole ear part includes a connection area, a first folding area and a second folding area. One side of the connection area is connected to the first side edge of the main body part. The dimension of the connection area along the first side edge is smaller than the length of the first side edge of the main body part. The connection area has a first side edge and a second side edge which are oppositely arranged and connected to the first side edge of the main body part. One end of the first folding area is connected to the first side edge of the connection area and extends in a direction away from the first side edge. One end of the second folding area is connected to the second side edge of the connection area and extends in a direction away from the second side edge.

[0008] Optionally, the first folding area and the second folding area are on the same straight line.

[0009] Optionally, the connecting area is rectangular, the first folding area and the second folding area are rectangular, the first folding area is perpendicular to the first side edge of the connecting area, and the second folding area is perpendicular to the second side edge of the connecting area.

[0010] Optionally, the distance between one end of the first folding area away from the first side edge of the connecting area and one end of the second folding area away from the second side edge of the connecting area is less than the length of the first side edge of the main body portion;

[0011] The main body portion has a second side edge and a third side edge which are oppositely arranged. The second side edge is connected to one end of the first side edge, and the third side edge is connected to the other end of the first side edge. One end of the first folding area away from the first side edge of the connecting area does not extend beyond the second side edge, and one end of the second folding area away from the second side edge of the connecting area does not extend beyond the third side edge.

[0012] Optionally, the first folding area is parallel to the first side edge of the main body portion, and the second folding area is parallel to the first side edge of the main body portion;

[0013] The distance between one end of the first folding area away from the connecting area and the first side edge is less than the width of the connecting area, and the distance between one end of the second folding area away from the connecting area and the second side edge is less than the width of the connecting area.

[0014] According to the current collector of the embodiment of the present invention, when assembling the electrode core, the first folding areas of the current collectors in the same-polarity electrode sheets in the electrode core can be folded to the outside of the electrode sheets located on one side of all the electrode sheets of this polarity, and welded to the outer surface of this electrode sheet. The second folding areas of the current collectors in each of these polarity electrode sheets in the electrode core can be folded to the outside of the electrode sheets located on the other side of all the electrode sheets of this polarity, and welded to the outer surface of this electrode sheet, so as to connect the current collectors of the same-polarity electrode sheets in the electrode core together. Compared with the prior art, there is no need to design a conductive sheet, which simplifies the installation steps and improves the installation efficiency.

[0015] On the other hand, the embodiment of the present invention provides an electrode sheet, including an active material layer and the above-mentioned current collector, and the active material layer is disposed on both surfaces of the main body portion in the thickness direction

[0016] On the other hand, the embodiment of the present invention provides an electrode core, including a plurality of the above-mentioned electrode sheets.

[0017] Optionally, it further includes a separator. The plurality of electrode plates are divided into positive electrode plates and negative electrode plates. The separator is clamped between the positive electrode plates and the negative electrode plates. The active material layer on the positive electrode plate is a positive electrode active material layer, and the active material layer on the negative electrode plate is a negative electrode active material layer.

[0018] Optionally, the positive electrode plates and the negative electrode plates are alternately arranged, and the positive electrode plates, the separator, and the negative electrode plates are stacked. The distances between the first folding regions and the first side edges of the electrode plates with the same polarity are different, and the distances between the second folding regions and the first side edges of the electrode plates with the same polarity are different.

[0019] Define the two positive electrode plates located on both sides of all the electrode plates as the first side positive electrode plate and the second side positive electrode plate respectively. The first folding region of each positive electrode plate is folded towards the side of the connection region of the first side positive electrode plate facing away from the second side positive electrode plate and is connected to the surface of the connection region of the first side positive electrode plate facing away from the second side positive electrode plate. The second folding region of each positive electrode plate is folded towards the side of the connection region of the second side positive electrode plate facing away from the first side positive electrode plate and is connected to the surface of the connection region of the second side positive electrode plate facing away from the first side positive electrode plate.

[0020] Define the two negative electrode plates located on both sides of all the electrode plates as the first side negative electrode plate and the second side negative electrode plate respectively. The first folding region of each negative electrode plate is folded towards the side of the connection region of the first side negative electrode plate facing away from the second side negative electrode plate and is connected to the surface of the connection region of the first side negative electrode plate facing away from the second side negative electrode plate. The second folding region of each negative electrode plate is folded towards the side of the connection region of the second side negative electrode plate facing away from the first side negative electrode plate and is connected to the surface of the connection region of the second side negative electrode plate facing away from the first side negative electrode plate.

[0021] On the other hand, an embodiment of the present invention provides a battery, including a housing and the above-mentioned electrode core, and the electrode core is disposed in the housing. Description of the Drawings

[0022] Figure 1 It is a schematic structural diagram of a current collector provided by an embodiment of the present invention;

[0023] Figure 2 is Figure 1 another perspective;

[0024] Figure 3 It is a schematic structural diagram of an electrode plate provided by an embodiment of the present invention;

[0025] Figure 4Structural schematic diagram of the electrode core provided by an embodiment of the present utility model;

[0026] Figure 5 is Figure 3 partial enlargement Figure 1 ;

[0027] Figure 6 is Figure 3 partial enlargement Figure 2 .

[0028] The reference numerals in the specification are as follows: 100, current collector; 1, main body part; 2, second side edge; 3, third side edge; 4, electrode tab; 5, connection area; 6, first side edge; 7, first folding area; 8, second side edge; 9, second folding area; 10, first metal layer; 11, base film; 12, second metal layer; 13, electrode sheet; 14, active material layer; 15, positive electrode sheet; 16, positive electrode active material layer; 17, first side positive electrode sheet; 18, second side positive electrode sheet; 19, separator; 20, negative electrode sheet; 21, negative electrode active material layer; 22, first side negative electrode sheet; 23, second side negative electrode sheet; 24, first side edge. Detailed implementation manners

[0029] In order to make the technical problems, technical solutions and beneficial effects solved by the present utility model clearer and more understandable, the present utility model will be 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 utility model and are not used to limit the present utility model.

[0030] As Figure 1 and Figure 2 shown, an embodiment of the present utility model provides a current collector 100, which includes a base film 11, a first metal layer 10 and a second metal layer 12. The first metal layer 10 is disposed on one surface of the base film 11 in the thickness direction, and the second metal layer 12 is disposed on the other surface of the base film 11 in the thickness direction. The current collector 100 is divided into a main body part 1 and an electrode tab 4, and both surfaces of the main body part 1 in the thickness direction are adapted to be provided with an active material layer 14.

[0031] The main body portion 1 has a first side edge 24. The tab portion 4 includes a connection region 5, a first folding region 7, and a second folding region 9. One side of the connection region 5 is connected to the first side edge 24 of the main body portion 1. The dimension of the connection region 5 along the first side edge 24 is smaller than the length of the first side edge 24 of the main body portion 1. The connection region 5 has a first side edge 6 and a second side edge 8 which are oppositely arranged and are in contact with the first side edge 24 of the main body portion 1. One end of the first folding region 7 is connected to the first side edge 6 of the connection region 5 and extends away from the first side edge 6. One end of the second folding region 9 is connected to the second side edge 8 of the connection region 5 and extends away from the second side edge 8.

[0032] In one embodiment, the first folding region 7 and the second folding region 9 are on the same straight line.

[0033] The first folding region 7 and the second folding region 9 have the same width and are on the same straight line, which is convenient for cutting.

[0034] In one embodiment, the connection region 5 is rectangular, the first folding region 7 and the second folding region 9 are rectangular, the first folding region 7 is perpendicular to the first side edge 6 of the connection region 5, and the second folding region 9 is perpendicular to the second side edge 8 of the connection region 5.

[0035] The connection region 5 is square, the first folding region 7 and the second folding region 9 are both rectangular. The width end of the first folding region 7 is connected to the first side edge 6 of the connection region 5, and the width end of the second folding region 9 is connected to the second side edge 8 of the connection region 5. The first folding region 7 is perpendicular to the first side edge 6 of the connection region 5, and the second folding region 9 is perpendicular to the second side edge 8 of the connection region 5. The first folding region 7, the second folding region 9, and the connection region 5 are all rectangular, with a relatively regular structure, which is convenient for cutting and connection.

[0036] In one embodiment, the distance between the end of the first folding region 7 away from the first side edge 6 of the connection region 5 and the end of the second folding region 9 away from the second side edge 8 of the connection region 5 is smaller than the length of the first side edge 24 of the main body portion 1.

[0037] The main body portion 1 has a second side edge 2 and a third side edge 3 which are oppositely arranged. The second side edge 2 is in contact with one end of the first side edge 24, and the third side edge 3 is in contact with the other end of the first side edge 24. The end of the first folding region 7 away from the first side edge 6 of the connection region 5 does not extend beyond the second side edge 2, and the end of the second folding region 9 away from the second side edge 8 of the connection region 5 does not extend beyond the third side edge 3.

[0038] The distance between one end of the first side edge 6 of the first folding area 7 away from the connection area 5 and one end of the second side edge 8 of the second folding area 9 away from the connection area 5 is less than the length of the first side edge 24 of the main body portion 1. The total length of the connection area 5, the first folding area 7, and the second folding area 9 along the first side edge 24 is less than the length of the first side edge 24, which is beneficial to reducing the area of the tab portion 4 and improving the energy density of the battery.

[0039] In one embodiment, the first folding area 7 is parallel to the first side edge 24 of the main body portion 1, and the second folding area 9 is parallel to the first side edge 24 of the main body portion 1.

[0040] The distance between one end of the first folding area 7 away from the connection area 5 and the first side edge 6 is less than the width of the connection area 5, and the distance between one end of the second folding area 9 away from the connection area 5 and the second side edge 8 is less than the width of the connection area 5.

[0041] The first folding area 7 and the second folding area 9 are parallel to the first side edge 24 of the main body portion 1. The first folding area 7 is connected to the waist of the first side edge 6 of the connection area 5, and the distance between the first folding area 7 and the first side edge 24 is greater than half of the length of the first side edge 6 of the connection area 5. The second folding area 9 is connected to the waist of the second side edge 8 of the connection area 5, and the distance between the second folding area 9 and the second side edge 2 is greater than half of the length of the second side edge 8 of the connection area 5. The length of the first folding area 7 is less than the width of the connection area 5, and the length of the second folding area 9 is less than the width of the connection area 5.

[0042] For the current collector 100 in the embodiment of the present invention, its working principle is as follows: When assembling the electrode core, the first folding areas 7 of the current collectors 100 in each same-polarity electrode plate 13 in the electrode core can be folded towards the outside of the electrode plates 13 on one side among all the electrode plates 13 of this polarity and welded to the outer surface of this electrode plate 13. The second folding areas 9 of the current collectors 100 in each of these electrode plates 13 in the electrode core can be folded towards the outside of the electrode plates 13 on the other side among all the electrode plates 13 of this polarity and welded to the outer surface of this electrode plate 13, so as to connect the current collectors 100 of the same-polarity electrode plates 13 in the electrode core together.

[0043] Compared with the prior art, there is no need to design a conductive sheet, which simplifies the installation steps and improves the installation efficiency.

[0044] In other embodiments, the first folding area 7 and the second folding area 9 are arranged in an interleaved manner.

[0045] In other embodiments, the first folding area 7 is arranged obliquely on the first side edge 6 of the connection area 5, and the second folding area 9 is obliquely connected to the second side edge 8 of the connection area 5.

[0046] In other embodiments, the first folding region 7 and the second folding region 9 may also be triangular.

[0047] In addition, an embodiment of the present utility model provides a pole piece 13, as Figure 3 shown, including an active material layer 14 and the current collector 100 described above, and the active material layer 14 is disposed on both surface sides of the main body portion 1 in the thickness direction.

[0048] In addition, an embodiment of the present utility model provides a pole core, as Figures 4 to 6 shown, including a plurality of the above-mentioned pole pieces 13.

[0049] The pole core further includes a separator 19. The plurality of pole pieces 13 are divided into a positive pole piece 15 and a negative pole piece 20. The separator 19 is clamped between the positive pole piece 15 and the negative pole piece 20. The active material layer 14 on the positive pole piece 15 is a positive electrode active material layer 16, and the active material layer 14 on the negative pole piece 20 is a negative electrode active material layer 21.

[0050] The positive pole piece 15 and the negative pole piece 20 are alternately arranged, and the positive pole piece 15, the separator 19 and the negative pole piece 20 are stacked. The distances between the first folding region 7 of each pole piece 13 with the same polarity and the first side edge 24 are different, and the distances between the second folding region 9 of each pole piece 13 with the same polarity and the first side edge 24 are different.

[0051] The two positive pole pieces 15 located on both sides among all the pole pieces 13 are respectively defined as a first-side positive pole piece 17 and a second-side positive pole piece 18. The first folding region 7 of each positive pole piece 15 is folded towards the side of the connection region 5 of the first-side positive pole piece 17 facing away from the second-side positive pole piece 18, and is connected to the surface of the side of the connection region 5 of the first-side positive pole piece 17 facing away from the second-side positive pole piece 18 (the first metal layer 10 on the connection region 5 of the current collector 100 of the first-side positive pole piece 17). The second folding region 9 of each positive pole piece 15 is folded towards the side of the connection region 5 of the second-side positive pole piece 18 facing away from the first-side positive pole piece 17, and is connected to the surface of the side of the connection region 5 of the second-side positive pole piece 18 facing away from the first-side positive pole piece 17 (the second metal layer 12 on the connection region 5 of the current collector 100 of the second-side positive pole piece 18), so as to connect the current collectors 100 of each positive pole piece 15 together.

[0052] Define the two negative electrode plates 20 located on both sides among all the electrode plates 13 as the first-side negative electrode plate 22 and the second-side negative electrode plate 23 respectively. The first folding regions 7 of each negative electrode plate 20 are folded towards the side of the connection region 5 of the first-side negative electrode plate 22 facing away from the second-side negative electrode plate 23, and are connected to the surface of the connection region 5 of the first-side negative electrode plate 22 facing away from the second-side negative electrode plate 23 (the first metal layer 10 on the connection region 5 of the current collector 100 of the first-side negative electrode plate 22). The second folding regions 9 of each negative electrode plate 20 are folded towards the side of the connection region 5 of the second-side negative electrode plate 23 facing away from the first-side negative electrode plate 22, and are connected to the surface of the connection region 5 of the second-side negative electrode plate 23 facing away from the first-side negative electrode plate 22 (the second metal layer 12 on the connection region 5 of the current collector 100 of the second-side negative electrode plate 23), so as to connect the current collectors 100 of each negative electrode plate 20 together.

[0053] In addition, an embodiment of the present invention provides a battery, including a housing and the above-mentioned electrode core, and the electrode core is arranged in the housing.

[0054] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A current collector, characterized in that: The current collector (100) comprises a base film (11), a first metal layer (10) and a second metal layer (12), wherein the first metal layer (10) is arranged on one side surface of the base film (11) in the thickness direction, and the second metal layer (12) is arranged on the other side surface of the base film (11) in the thickness direction. The current collector (100) is divided into a main body portion (1) and a lug portion (4), and both side surfaces of the main body portion (1) in the thickness direction are suitable for arranging an active material layer (14); The main body (1) has a first side edge (24); the pole ear (4) comprises a connection area (5), a first folding area (7) and a second folding area (9); one side of the connection area (5) is connected to the first side edge (24) of the main body (1); the size of the connection area (5) along the first side edge (24) is smaller than the length of the first side edge (24) of the main body (1); the connection area (5) has a first side edge (6) and a second side edge (8) which are arranged opposite to each other and connected to the first side edge (24) of the main body (1); one end of the first folding area (7) is connected to the first side edge (6) of the connection area (5) and extends in a direction away from the first side edge (6); one end of the second folding area (9) is connected to the second side edge (8) of the connection area (5) and extends in a direction away from the second side edge (8).

2. The current collector according to claim 1, characterized in that: The first folding area (7) and the second folding area (9) are on the same straight line.

3. The current collector according to claim 2, characterized in that: The connecting area (5) is rectangular, the first folding area (7) and the second folding area (9) are rectangular, the first folding area (7) is perpendicular to a first side edge (6) of the connecting area (5), and the second folding area (9) is perpendicular to a second side edge (8) of the connecting area (5).

4. The current collector according to claim 3, characterized in that: The distance between one end of the first folding area (7) away from the first side edge (6) of the connecting area (5) and one end of the second folding area (9) away from the second side edge (8) of the connecting area (5) is less than the length of the first side edge (24) of the main body (1); The main body (1) has a second side edge (2) and a third side edge (3) which are arranged opposite to each other, the second side edge (2) is connected to one end of the first side edge (24), the third side edge (3) is connected to the other end of the first side edge (24), the end of the first folding area (7) away from the first side edge (6) of the connecting area (5) does not exceed the second side edge (2), and the end of the second folding area (9) away from the second side edge (8) of the connecting area (5) does not exceed the third side edge (3).

5. The current collector according to claim 4, characterized in that: The first folding area (7) is parallel to the first side edge (24) of the main body (1), and the second folding area (9) is parallel to the first side edge (24) of the main body (1); The distance between one end of the first folding area (7) away from the connecting area (5) and the first side edge (6) is smaller than the width of the connecting area (5), and the distance between one end of the second folding area (9) away from the connecting area (5) and the second side edge (8) is smaller than the width of the connecting area (5).

6. A pole piece, characterized in that: It comprises an active material layer (14) and a current collector (100) according to any one of claims 1 to 5, wherein the active material layer (14) is arranged on both side surfaces of the main body (1) in the thickness direction.

7. A pole core, characterized in that: Comprising a plurality of pole pieces (13) as claimed in claim 6.

8. The pole core according to claim 7, characterized in that: The invention also comprises a separator (19), wherein the plurality of electrode sheets (13) are divided into a positive electrode sheet (15) and a negative electrode sheet (20), the separator (19) is sandwiched between the positive electrode sheet (15) and the negative electrode sheet (20), the active material layer (14) on the positive electrode sheet (15) is a positive electrode active material layer (16), and the active material layer (14) on the negative electrode sheet (20) is a negative electrode active material layer (21).

9. The pole core according to claim 8, characterized in that: The positive electrode sheets (15) and the negative electrode sheets (20) are arranged alternately, the positive electrode sheets (15), the separator (19) and the negative electrode sheets (20) are arranged in a stacked manner, the distance between the first folding area (7) and the first side edge (24) of each electrode sheet (13) of the same polarity is different, and the distance between the second folding area (9) and the first side edge (24) of each electrode sheet (13) of the same polarity is different; The two positive electrode sheets (15) located on both sides of all the electrode sheets (13) are respectively defined as a first side positive electrode sheet (17) and a second side positive electrode sheet (18); the first folding area (7) of each positive electrode sheet (15) is folded toward the side of the connection area (5) of the first side positive electrode sheet (17) facing away from the second side positive electrode sheet (18), and is connected to the side surface of the connection area (5) of the first side positive electrode sheet (17) facing away from the second side positive electrode sheet (18); the second folding area (9) of each positive electrode sheet (15) is folded toward the side of the connection area (5) of the second side positive electrode sheet (18) facing away from the first side positive electrode sheet (17), and is connected to the side surface of the connection area (5) of the second side positive electrode sheet (18) facing away from the first side positive electrode sheet (17); The two negative electrode sheets (20) located on both sides of all the electrode sheets (13) are respectively defined as a first side negative electrode sheet (22) and a second side negative electrode sheet (23); the first folding area (7) of each negative electrode sheet (20) is folded toward the side of the connection area (5) of the first side negative electrode sheet (22) facing away from the second side negative electrode sheet (23), and is connected to the side surface of the connection area (5) of the first side negative electrode sheet (22) facing away from the second side negative electrode sheet (23); the second folding area (9) of each negative electrode sheet (20) is folded toward the side of the connection area (5) of the second side negative electrode sheet (23) facing away from the first side negative electrode sheet (22), and is connected to the side surface of the connection area (5) of the second side negative electrode sheet (23) facing away from the first side negative electrode sheet (22).

10. A battery, characterized in that: It comprises a shell and the pole core as described in any one of claims 7 to 9, wherein the pole core is arranged in the shell.

Images