Uncovering collaboration and knowledge areas in lithium-ion battery recycling

Schlehuber, Simon; Hemmelder, André; von Delft, Stephan

Abstract

The ongoing adoption of lithium-ion batteries (LIBs) in electric vehicles (EVs) and portable electronics has created an urgent need to address the looming challenge of managing the drastic increase in end-of-life batteries through effective recycling solutions. However, the battery recycling landscape remains complex due to the lack of a dominant recycling solution, primarily attributed to differences in battery chemistries and designs. This study contributes a comprehensive patent analysis in this field to track the evolving technological landscape across three time periods, spanning from 1990 to 2024, identify emerging trends and guide strategic decision-making in the rapidly growing battery recycling market. The patent analysis is structured as follows: first, a co-occurrence network analysis of patent assignees is performed to elucidate collaboration in the field. Second, key knowledge areas in LIB recycling are identified through clustering and subsequent natural language processing of co-occurring Cooperative Patent Classification (CPC) class networks. Third, these results are consolidated into two-mode networks to link each patent assignee to its knowledge stocks. The findings reveal a notable lack of international collaboration, which is particularly problematic for Western countries that currently hold minimal presence in the patent landscape. The results also assist in pinpointing the knowledge stocks of different patent assignees and may facilitate the discovery of new research topics and potential collaborators or competitors.