Repaired and regenerated waste lithium iron phosphate positive electrode material and repairing and regenerating method

• Main Authors: WANG CHAOLEI, TONG HUI, GUO XUEYI, DING ZHIYING, TIAN QINGHUA, YU WANJING, LI YI
• Format: Patent
• Language: Chinese; English
• Published: 02.11.2021
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS THEREOF; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention discloses a repaired and regenerated waste lithium iron phosphate positive electrode material and a repairing and regenerating method. The method comprises the following steps of: (1) uniformly mixing a waste lithium iron phosphate positive electrode material with a material A, a carbon source and metal added ions to obtain a mixed material B, the material A comprising lithium carbonate and lithium hydroxide which are uniformly mixed; and (2) carrying out low-temperature roasting on the mixed material B in an inert or reducing atmosphere, and cooling to obtain a repaired and regenerated waste lithium iron phosphate material. The repaired and regenerated waste lithium iron phosphate positive electrode material is of a core-shell coating structure, a coating layer is a carbon layer, and lithium iron phosphate doped with metal additive ions is coated with the carbon layer. According to the low eutectic salt principle, lithium supplementation regeneration is carried out on a waste lithium iron phosp