Method for recovering lithium in waste lithium iron phosphate battery

• Main Authors: ZHONG FAPING, XIONG YIZHI, TAN SHUIFA, CHEN JIE, JIANG SUBIN, HE CHIHUAN, LIU HONGBING, ZHU JIQUN
• Format: Patent
• Language: Chinese; English
• Published: 26.07.2024
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM,RUBIDIUM, CAESIUM, OR FRANCIUM; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention provides a method for recycling lithium in a waste lithium iron phosphate battery, which comprises the following steps of: putting positive electrode black powder of the waste lithium iron phosphate battery into a roasting treatment furnace filled with protective gas for roasting reaction, and adjusting the flow of input chlorine gas based on a mixture in the roasting treatment furnace so as to control the roasting reaction temperature, the roasting reaction temperature is 50-300 DEG C; carrying out water immersion on the roasted product after the roasting reaction to obtain a roasted product solution; carrying out suction filtration on the roasted product solution to obtain filtrate; and evaporating and concentrating the filtrate, and drying to obtain the lithium chloride crystal. According to the method, one-step roasting is carried out at low temperature, the roasting reaction temperature is controlled by adjusting the flow of the filled chlorine, the lithium element in the waste lithium iron