Preparation method of positive and negative conductive liquid storage layer slurry and thick electrode

Abstract

The invention discloses a preparation method of positive and negative conductive liquid storage layer slurry and a thick electrode. Positive / negative electrode conductive liquid storage layer slurry is prepared, a current collector (3) is coated with the positive / negative electrode slurry, the positive / negative electrode conductive liquid storage layer slurry is sprayed after drying, a layer of positive / negative electrode slurry is coated after drying, and the positive / negative electrode pole piece of the sandwich structure of the active layer (1), a conductive liquid storage layer (2) and theactive layer (1) is obtained through cold pressing and slitting after drying. Through the introduction of the conductive liquid storage layer, the problem of poor dynamics caused by the thickening ofthe existing electrode is solved, the direct-current internal resistance and the high-rate capacity are greatly improved when the same coating surface density is achieved, and the dynamics performance is better; when the surface density is increased by 15%, the similar dynamic performance is still kept; and moreover, the energy density of the prepared battery is improved by 1-1.5% compared with that of a conventional battery under the same positive electrode surface density (520-600g / m<2>).

Description

technical field

[0001] The invention relates to the technical field of lithium ion batteries, in particular to a method for preparing positive and negative conductive liquid storage layer slurry and thick electrodes. Background technique

[0002] As the energy density requirements of lithium-ion batteries increase year by year, related technical research is also getting deeper and deeper. From the perspective of existing technical reports, improving the energy density mainly starts from two aspects: (1) increasing the gram capacity of the positive and negative electrode materials. At present, the research has encountered a bottleneck, and the mature positive and negative electrode materials are close to the theoretical gram capacity. There is little chance of continued improvement or significant damage to other properties. Therefore, the material system must be completely replaced to achieve a qualitative breakthrough. In the short term, it is still very difficult; (2) Incr...

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