Challenges of Stable Ion Pathways in Cathode Electrode for All-Solid-State Lithium Batteries: A Review

摘要

For energy storage devices, high energy density, high power density, cycle stability,and safety are the development goals. Solid-state lithium metal batteries,with both safety and high performance, have become a hot topic in recentresearch. Although each component of these batteries has been studied fordecades, and their individual performance has been improved markedly, theperformance of their combination is still far less than expected. Without theaid of a liquid electrolyte, the ion pathways within and between solid elementsare tortuous or even disconnected, making the cathode development in solidstatelithium metal batteries more challenging than for those in lithium-ionbatteries with liquid electrolytes. This review focuses on the ion pathways inthe cathode for all-solid-state lithium batteries with different dimensions, coveringtheir types, characteristics, and challenges. The design and modificationmethods of the ion pathways, including element doping, coating, compositepathways, and new functional structures, are also discussed.