Immature recycling technology

The available data show that the recycling treatment of waste lithium iron phosphate battery can be divided into two types: one is recycling metal, and the other is recycling lithium iron phosphate cathode material.
(1) Wet recovery of lithium and iron
This type of process mainly focuses on lithium recovery. Since lithium iron phosphate does not contain precious metals, the recovery process of lithium cobalt oxide has been modified. Firstly, the lithium iron phosphate battery is disassembled to obtain the cathode material, and then crushed and screened to obtain the powder; Afterwards, the alkaline solution is added to the powder to dissolve aluminum and its oxides, and filtered to obtain filter residue containing lithium, iron, etc; Leaching the filter residue with a mixed solution of sulfuric acid and hydrogen peroxide (reducing agent) to obtain the leaching solution; Precipitate iron hydroxide with alkali and filter to obtain the filtrate; Burning iron hydroxide can obtain iron oxide; Finally, adjust the pH value of the leaching solution (5.0~8.0), filter the leaching solution to obtain the filtrate, and add solid sodium carbonate to concentrate and crystallize to obtain lithium carbonate. [3]
(2) Regenerated lithium iron phosphate
The single recovery of a certain element results in lower economic benefits for the recovery of lithium iron phosphate without precious metals. Therefore, the solid phase method is mainly used to regenerate lithium iron phosphate battery, which has high recovery efficiency and high comprehensive utilization rate of resources.
Firstly, the lithium iron phosphate battery is disassembled to obtain the cathode material, and then crushed and screened to obtain the powder; After heat treatment, residual graphite and binder are removed, and then an alkaline solution is added to the powder to dissolve aluminum and its oxides; Filter the filter residue containing lithium, iron, etc., analyze the molar ratio of iron, lithium, and phosphorus in the filter residue, add iron, lithium, and phosphorus sources, and adjust the molar ratio of iron, lithium, and phosphorus to 1:1:1; Adding a carbon source, ball milling, and calcining in an inert atmosphere to obtain a new lithium iron phosphate cathode material.