Sustainable recovery of spent ternary cathode materials via wasted asphalt pyrolysis in closed-loop recycling

Abstract

With the continuous development of the lithium-ion battery (LIB) industry, the number of retired power batteries has been increased rapidly. The ternary cathode materials from spent batteries are rich in valuable elements such as lithium, nickel, and cobalt. It is of great significance to extract and reuse those metal elements. Herein, we proposed a favorable method for disintegrating spent cathode materials under the reductive gas obtained by pyrolysis of spent asphalt at a low temperature of 500 °C. The structure of the spent ternary material was completely decomposed under a mild condition, in which 97.3 wt% of Li was well released to form lithium carbonate. The treated transition-metal salt solution was employed to prepare a precursor through a simple hydrothermal process, and a ternary cathode material (NCM 811) with superior electrochemical performance was achieved. The impact on the economy and environment under this procedure was estimated by the Everbatt model. The greenhouse gas emission in this process was only 50.1 % of that from the pyrometallurgical treatment and 64.5 % of that in the hydrometallurgical process. The proposed green recycling strategy demonstrated the enormous potential for high value-added closed-loop recycling of spent ternary cathode materials.