Preparation method of lithium ion phosphate power battery cathode plate

Abstract

The invention provides a preparation method of a lithium ion phosphate power battery cathode plate. The method comprises the following steps: (1) adding an adhesive for preparing a cathode material to a solvent, and stirring and fully dissolving the adhesive to prepare a solution; (2) adding a conductive agent, an additive and lithium ion phosphate to the solution prepared in the step (1) respectively, and stirring the conductive agent, the additive and the lithium ion phosphate evenly at a high speed to prepare cathode slurry; (3) coating a cathode current collector with the slurry prepared in the step (2) to form a cathode material layer; and (4) coating the cathode material layer with a coating layer for improving the safety of the cathode plate, and carrying out drying, rolling and slitting to prepare the lithium-ion battery cathode plate. The additive is prepared from the following raw materials in percentage by weight: 1%-20% of ethanol, 10%-30% of N-methylpyrrolidone and 50%-85% of ethylene carbonate. The preparation method can obviously improve dusting of the lithium ion phosphate cathode plate and improves gram volume development of the lithium iron phosphate; the cost is low; and the operation is simple and easy.

Description

technical field [0001] The invention relates to the technical field of lithium batteries, in particular to a method for preparing a positive electrode sheet of a lithium iron phosphate power battery. Background technique [0002] At present, with the rapid development of portable electronic devices such as mobile phones, digital cameras, and notebook computers, the market demand for high-power, high-energy-density batteries is increasing. Lithium-ion battery is the battery with the highest voltage and the largest energy density among the batteries that have been practical so far, and has a good development prospect. [0003] Lithium iron phosphate battery is a new type of lithium ion battery that has attracted widespread attention in recent years. Because lithium iron phosphate (LiFePO4) material has high specific energy, long cycle life, stable structure, good safety performance, and low cost, it has high quality as a power battery. High specific energy, low unit price / lif...

AI Technical Summary

Problems solved by technology

However, during the coating process, a large amount of gas containing NMP is discharged into the air, polluting the environment, and at the same time, the cost of NMP is high, which increases the production cost of the battery

Therefore, the formulation of the water-based system can avoid environmental pollution and reduce production costs and has been widely used. However, since the positive electrode sheet made of LA series water-based adhesives such as LA132 in the water-based system is relatively hard, it is very easy to process in the cutting process. There is a phenomenon of powder falling, and the gram capacity of the positive active material is also lower than that of the oily system