Progress and prospects of energy storage technology research: Based on multidimensional comparison

The development of energy storage technology (EST) has become an important guarantee for solving the volatility of renewable energy (RE) generation and promoting the transformation of the power system. How to scientifically and effectively promote the development of EST, and reasonably plan the layout of energy storage, has become a key task in successfully coping with energy transformation. However, there are still different understandings among different research forces worldwide regarding the research direction and focus of EST. Therefore, the goal of this study is to explore the spatiotemporal heterogeneity of EST types, research institutions, and key technologies in major economies around the world, and to reveal the evolution laws of EST under different regions and dimensions. This study uses Citespace software and LDA topic modeling method to conduct research on the United States, Japan, Europe, and China as study areas, and 87,717 collected documents as research objects. The results show that, in terms of technology types, the annual publication volume and publication ratio of various energy storage types from high to low are: electrochemical energy storage, electromagnetic energy storage, chemical energy storage, thermal energy storage, and mechanical energy storage. In terms of regional dimension, there are some differences in research types, research stability, and key technologies among different economies. In terms of time dimension, most technology topics show trends of "split", "fusion", "emergence", and "extinction". Finally, this study provides decision-making references for the scientific and technological layout, cooperation and mutual benefit, and resource allocation among various economies.