Research on technological evolution and lock-in of all-solid-state lithium batteries from a path perspective

As a next-generation energy storage technology, all-solid-state lithium batteries possess important strategic significance for safeguarding national energy security and realizing independent controllability of industrial chains. Clarifying the technological evolution patterns in this field facilitates the identification of potential path lock-in risks and possible breakthrough directions, thereby supporting the high-quality development and high-level security of relevant national technologies and industries. Based on patent citation data, this paper comprehensively adopts methods such as community detection, main path extraction, and recent scientific publications association analysis to conduct research from the perspectives of technological evolution trajectory, path lock-in and unlocking directions. The results show that the main path of sulfide electrolytes presents obvious lock-in characteristics, with dominant technologies along the identified main path concentrated among Japanese institutional applicants, evolving around the topics of preparation methods, sulfide glass electrolytes, argyrodite-type electrolytes and phosphorus pentasulfide composition. The extracted main path for garnet-type oxide electrolytes also exhibits prominent path lock-in, with recent dominant technologies along this main path originating from American QuantumScape Corporation, focusing on high-temperature solid-state reaction methods, electrolyte doping and sintering processes. The main path of electrode/electrolyte interfaces tends to converge, with Chinese institutional applicants serving as core participants in technological innovation along this path, which encompasses protective layers, buffer layers, composite electrodes, battery structure design and electrolyte modification. Aiming at the path lock-in issue, unlocking strategies can be formulated from two dimensions: trajectory-following innovation paths and technological leapfrogging paths.