High-energy-density pole piece and battery cell

Abstract

The utility model relates to a high-energy density pole piece and a battery cell, the high-energy density pole piece comprises an insulating layer, two side surfaces of the insulating layer are respectively provided with an anode film and a cathode film, one side of the anode film far away from the insulating layer is provided with an anode coating, and one side of the cathode film far away from the insulating layer is provided with a cathode coating. According to the high-energy-density pole piece provided by the utility model, the anode film and the cathode film are respectively formed on the two sides of the insulating layer, and the mass of the current collector is reduced through the composite action of the anode film, the cathode film and the insulating layer, so that the weight of a battery cell can be reduced, and the energy density is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a high energy density electrode sheet and an electric core. Background Art

[0002] Silicon-carbon anode has the advantages of high energy density and suitable discharge platform, and is one of the potential next-generation anode materials. In the past few years, due to reasons such as high product price and immature supporting industrial chain, the industrialization progress of silicon-carbon anode has fallen short of expectations. However, since 2021, enterprises such as Tesla and CATL have successively started mass-producing power battery products using silicon-carbon anodes, and some anode enterprises have also started investing in the construction of silicon-carbon anode production lines. The application of silicon-carbon anodes has gradually become mature. However, due to the relatively high weight ratio of the current collector used in the production process of the electrode sheet, it is difficult to improve the energy density, and the cruising range of the whole vehicle is limited, so it is urgent to improve. Content of the Utility Model

[0003] Based on this, in view of the technical problem that the energy density is difficult to improve and the cruising range of the whole vehicle is limited due to the relatively high weight ratio of the current collector used in the production process of the electrode sheet, the utility model provides a high energy density electrode sheet and an electric core.

[0004] A high energy density electrode sheet provided by the utility model includes an insulating layer, an anode film and a cathode film are respectively arranged on both sides of the insulating layer, an anode coating is arranged on the side of the anode film away from the insulating layer, and a cathode coating is arranged on the side of the cathode film away from the insulating layer.

[0005] The high energy density electrode sheet provided by the utility model realizes the reduction of the mass of the current collector by forming the anode film and the cathode film on both sides of the insulating layer respectively, and through the composite action of the anode film, the cathode film and the insulating layer, so as to be able to reduce the weight of the electric core, realize the improvement of the energy density, and thus increase the cruising range of the whole vehicle.

[0006] As a further improvement of the above scheme of the utility model, the thickness of the insulating layer is 2-4μm.

[0007] As a further improvement of the above scheme of the utility model, the insulating layer adopts a PE film.

[0008] As a further improvement of the above scheme of the utility model, the thickness of the anode film is 1-3μm.

[0009] As a further improvement of the above scheme of the utility model, the anode film adopts a copper film.

[0010] As a further improvement of the above scheme of the utility model, the thickness of the cathode film is 1-3μm.

[0011] As a further improvement of the above scheme of the utility model, the cathode film adopts an aluminum film.

[0012] A battery cell provided by the present utility model includes a plurality of negative electrode plates, a plurality of separators, and a plurality of positive electrode plates. The negative electrode plates and the positive electrode plates are alternately arranged, and a separator is provided between each positive electrode plate and each negative electrode plate. The negative electrode plate includes the high-energy density electrode plate and a negative electrode tab as described above, and the negative electrode tab is electrically connected to the anode film of the high-energy density electrode plate.

[0013] As a further improvement of the above solution of the present utility model, the positive electrode plate includes the high-energy density electrode plate and a positive electrode tab as described above, and the positive electrode tab is electrically connected to the cathode film of the high-energy density electrode plate.

[0014] As a further improvement of the above solution of the present utility model, the negative electrode tab is made of a copper tab, and the positive electrode tab is made of an aluminum tab.

[0015] Compared with the prior art, the present utility model has the following beneficial effects:

[0016] The high-energy density electrode plate provided by the present utility model forms an anode film and a cathode film on both sides of the insulating layer respectively. Through the composite action of the anode film, the cathode film and the insulating layer, the positive and negative electrode materials are coated on both sides, which greatly reduces the mass of the battery cell and effectively improves the energy density of the battery cell, thereby increasing the cruising range of the whole vehicle; the high-energy density electrode plate provided by the present utility model has a simple structure, is easy to implement and has a low cost, meeting the actual production requirements.

[0017] When the high-energy density electrode plate provided by the present utility model is produced, since the positive and negative electrodes can be coated simultaneously, the production process can be completed by using one coater, reducing the procurement requirements of equipment and saving costs. Description of the Drawings

[0018] Figure 1 It is a schematic structural diagram of a high-energy density electrode plate proposed by an embodiment of the present utility model;

[0019] Figure 2 It is a schematic structural diagram of a battery cell proposed by an embodiment of the present utility model.

[0020] Reference numerals: 1, insulating layer; 2, anode film; 3, cathode film; 4, anode coating; 5, cathode coating; 6, separator; 7, negative electrode tab; 8, positive electrode tab. Detailed Embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] Referring Figure 1 , this embodiment provides a high energy density electrode sheet, including an insulating layer 1, an anode film 2, a cathode film 3, an anode coating 4, and a cathode coating 5.

[0023] The insulating layer 1 is made of a PE film with a thickness of 2 - 4 μm, mainly serving as an insulator.

[0024] The anode film 2 and the cathode film 3 are respectively disposed on both side surfaces of the insulating layer 1. In this embodiment, the anode film 2 is made of a copper film with a thickness of 1 - 3 μm. In this embodiment, the cathode film 3 is made of an aluminum film with a thickness of 1 - 3 μm. Specifically, in this embodiment, the anode film 2 and the cathode film 3 can be respectively disposed on both side surfaces of the insulating layer 1 through the following steps: taking the insulating layer 1 material, using magnetron sputtering to deposit a copper material bottom layer of about 20 nm on one side of the insulating layer 1, and then using vacuum evaporation to thicken the copper coating on this side to the target thickness; rolling up the material roll with the copper layer deposited, and using vacuum evaporation to deposit an aluminum layer on the other side.

[0025] The anode coating 4 is disposed on the side of the anode film 2 away from the insulating layer 1. The anode coating 4 can be formed by coating the anode film 2 with a known negative electrode active paste. In this embodiment, the paste of the anode coating 4 is prepared from a silicon carbon + graphite composite material and an auxiliary conductive agent. The coating width of the anode coating 4 is 128 mm, and the coating surface density is 205 g / m 2 . Of course, in other embodiments, the paste of the anode coating 4 can also be prepared from graphite or a graphite + silicon oxide composite material and an auxiliary conductive agent, and the coating width and coating surface density of the anode coating 4 can also be reasonably designed according to actual situations.

[0026] The cathode coating 5 is disposed on the side of the cathode film 3 away from the insulating layer 1. The cathode coating 5 can be formed by coating the cathode film 3 with a known positive electrode active paste. In this embodiment, the paste of the cathode coating 5 is prepared from a 9 - series nickel - cobalt - manganese ternary material and an auxiliary conductive agent. The coating width of the cathode coating 5 is 124 mm, and the coating surface density is 353 g / m 2 . Of course, in other embodiments, the paste of the cathode coating 5 can also be prepared from a ternary material + lithium manganese iron phosphate material and an auxiliary conductive agent, and the coating width and coating surface density of the cathode coating 5 can also be reasonably designed according to actual situations.

[0027] The high-energy density electrode provided by this embodiment forms an anode film 2 and a cathode film 3 on both sides of the insulating layer 1 respectively. Through the composite action of the anode film 2, the cathode film 3 and the insulating layer 1, and by using a composite copper-aluminum foil as the carrier, the quality of the current collector is reduced, thereby reducing the weight of the battery cell and achieving an increase in energy density, and thus increasing the cruising range of the whole vehicle.

[0028] Referring to Figure 2 , based on the above high-energy density electrode, this embodiment further provides a battery cell, which includes a plurality of negative electrodes, a plurality of separators 6, and a plurality of positive electrodes. The negative electrodes and the positive electrodes are arranged alternately, and a separator 6 is provided between each positive electrode and each negative electrode. The negative electrode includes the above high-energy density electrode and a negative electrode tab 7. The negative electrode tab 7 is a copper tab and is welded to the anode film 2 of the high-energy density electrode. The positive electrode includes the above high-energy density electrode and a positive electrode tab 8. The positive electrode tab 8 is an aluminum tab and is welded to the cathode film 3 of the high-energy density electrode. The separator 6 of this embodiment adopts a known separator 6 in the art and will not be elaborated here.

[0029] The energy density of the soft-pack battery cell of this embodiment is 353 wh / kg. Compared with the traditional production process, the energy density is increased by about 40 wh / kg. It can be applied to multiple fields such as digital products, automobiles, and daily necessities. Through the structural innovation of the battery cell composition and the optimization of the production method, the energy density of the battery cell is increased, the cruising range is increased, and it is ensured that the product use meets the customer expectations.

[0030] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0031] The above-described embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the utility model patent should be subject to the appended claims.

Claims

1. A high energy density pole piece, characterized in that: It comprises an insulating layer (1), wherein an anode film (2) and a cathode film (3) are respectively arranged on two side surfaces of the insulating layer (1), an anode coating (4) is arranged on the side of the anode film (2) away from the insulating layer (1), and a cathode coating (5) is arranged on the side of the cathode film (3) away from the insulating layer (1).

2. The high energy density pole piece according to claim 1, characterized in that: The thickness of the insulating layer (1) is 2-4 μm.

3. The high energy density pole piece according to claim 1, characterized in that: The insulating layer (1) is made of PE film.

4. The high energy density pole piece according to claim 1, characterized in that: The thickness of the anode film (2) is 1-3 μm.

5. The high energy density pole piece according to claim 1, characterized in that: The anode film (2) is a copper film.

6. The high energy density pole piece according to claim 1, characterized in that: The thickness of the cathode film (3) is 1-3 μm.

7. The high energy density pole piece according to claim 1, characterized in that: The cathode film (3) is made of aluminum film.

8. A battery cell comprising a plurality of negative electrode sheets, a plurality of separators (6), and a plurality of positive electrode sheets, wherein the negative electrode sheets and the positive electrode sheets are arranged alternately and a separator (6) is arranged between each positive electrode sheet and each negative electrode sheet, characterized in that: The negative electrode plate comprises a high energy density electrode plate as described in any one of claims 1 to 7 and a negative electrode tab (7), and the negative electrode tab (7) is electrically connected to the anode film (2) of the high energy density electrode plate.

9. The battery cell according to claim 8, characterized in that: The positive electrode plate comprises a high energy density electrode plate as described in any one of claims 1 to 7 and a positive electrode tab (8), and the positive electrode tab (8) is electrically connected to the cathode film (3) of the high energy density electrode plate.

10. The battery cell according to claim 9, characterized in that: The negative electrode tab (7) is made of copper, and the positive electrode tab (8) is made of aluminum.

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