Unveiling the recycling characteristics and trends of spent lithium-ion battery: a scientometric study.

The recycling of spent lithium-ion batteries (LIBs) is both essential to sustainable resource utilization and environmental conservation. While spent batteries possess a resource value, they pose an environmental hazard at the same time. Since the start of development to recycle spent LIBs in 1990s, important contributions have been made and a number of achievements have been accomplished by scholars globally. Therefore, it is valuable to summarize the developments on spent LIB recycling and to analyze the characteristics and trends comprehensively. A review of the progress in this field will provide guidance for future development. In this study, recycling characteristics and developing trends including the research foundation, milestone, research hotspot, key technologies, and emerging trends were identified based on visual scientometric analysis followed by a discussion on future research directions in this area. For the analysis, 1041 publications in English were collected, summarized, and categorized. The distribution of scientific publications on spent LIB recycling from 1995 to 2020 displayed an increasing trend in numbers. China made the biggest contribution with 528 publications and basically cooperated with all other countries. The research fields with the highest contributions were "engineering", "chemistry", and "environmental science and technology". The keywords recovery, lithium ion battery, and cobalt appeared in high frequency. "Metal value" was identified as the most frequently used keyword which began to burst in 2005 and ended in 2013.