Solid−state lithium battery technology is an emerging field expected to overcome the current development bottlenecks of lithium−ion batteries and achieve "revolutionary innovation", which represents a critical area for major nations competing for dominance in "next−generation lithium battery technology". By analyzing global patent trends in solid−state lithium batteries, we can effectively grasp the international competitive landscape, identify key technological barriers and development opportunities, thereby providing support for the high−quality development and high−level security of China's related technologies and industries. Based on retrieval results from the IncoPat patent database, this paper integrates text mining with KeyBERT algorithm, CiteSpace visualization analysis, and Cooperative Patent Classification (CPC) analysis to conduct an in−depth investigation from perspectives of patent quantity, quality, and technology themes. The results indicate that patents in this field primarily originate from China, Japan, the United States, and the republic of Korea. China holds an absolute leading position in the quantity of technological achievements, but there remain deficiencies in technological integration and technological impact. The scope of legal protection remains relatively narrow, and the stability of patent rights needs to be improved. Furthermore, the patent deployment of Chinese entities is largely restricted to the domestic market, with limited adequacy in international patent deployment and constrained influence over the global market. The research focus and development pathways of major countries exhibit distinct priorities. Finally, recommendations for promoting the technological innovation and development of solid-state lithium battery in China are put forward from three aspects: clarify the directions of key technological breakthroughs and secure strategic positions in technological competition; strengthen patent deployment and standard formulation to enhance international discourse power; expand cooperation and exchange to aggregate innovation resources.