Environmental life cycle assessment of emerging solid-state batteries: A review

•This review summarizes the LCA studies on solid state batteries (SSBs) with the available inventory data, scope of the assessment as well as the life cycle impact assessment results for the SSBs.•Discrepancies involved in existing LCA studies has been pointed out with available LCAs on SSBs.•Unification methodology framework has been proposed for the comparative assessment of different LCA studies.•This study provides useful insights for the future LCA studies on SSBs.