Positive electrode slurry, positive electrode plate and lithium battery

Abstract

The invention discloses a positive electrode slurry, a positive electrode plate and a lithium battery, the positive electrode slurry comprises a binder, the binder comprises polyvinylidene fluoride and an additive, the chemical formula of the additive is shown in the specification, R1 comprises-H, CH3 or-OH, and R2 comprises-NHCH2CH3, N (CH2CH3) 2,-NH2 or-OH. By adopting the positive electrode slurry, the problems that a positive electrode plate is hard and brittle and the positive electrode slurry is too thick and cracked due to the positive electrode slurry only using PVDF as the binder in the prior art can be effectively solved, and by adopting the binder for the positive electrode slurry, the coating thickness of the positive electrode slurry can be improved while the flexibility of the positive electrode plate is improved; and meanwhile, hydrogen bond acting force can be formed between the positive electrode slurry and the positive electrode current collector, and the PVDF is subjected to cross-linking reaction in the coating and baking stages, so that the cohesion and stripping force of the positive electrode plate are improved, powder falling is reduced, and the cycle performance and safety performance of the battery are further improved.

Description

technical field [0001] The invention belongs to the field of lithium batteries, and particularly relates to a positive electrode slurry, a positive electrode pole piece and a lithium battery. Background technique [0002] With the development of lithium batteries, reducing the cost of lithium batteries on the premise of ensuring the safety of cells has become a hot spot. At present, the main means of reducing the cost of cells include increasing the coating thickness of the pole piece, increasing the compaction density of the pole piece, and developing lower-cost raw materials. Low-cost raw materials have the risk of long development time, large investment and performance uncertainty. Therefore, increasing the coating thickness of the pole piece and increasing the compaction density of the pole piece have become important means to reduce the cost of lithium batteries. However, the use of PVDF binder in the current positive electrode slurry leads to the hard and brittle posi...

AI Technical Summary

Problems solved by technology

For this reason, an object of the present invention is to propose a kind of positive electrode slurry, positive electrode sheet and lithium battery, and this positive electrode slurry can effectively solve the positive electrode sheet that only uses PVDF as the positive electrode slurry of binder in the prior art. Hard and brittle and the problems of over-thickness and cracking of the positive electrode slurry coating, and the positive electrode slurry composed of the present application can improve the flexibility of the positive electrode sheet while increasing the coating thickness of the positive electrode slurry, thereby increasing the thickness and thickness of the positive electrode sheet. At the same time, the hydrogen bond force can be formed between the positive electrode slurry and the positive electrode current collector, and the PVDF binder can be cross-linked during the coating and baking stage, improving the cohesion and peeling force of the positive electrode sheet, reducing the Powder, thereby improving the cycle performance and safety performance of the battery

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