Development strategies for heavy duty electric battery vehicles: Comparison between China, EU, Japan and USA

This paper investigates the development of heavy duty electric battery vehicles through analysing research papers and patents and identifies emerging technology areas by using a generative probabilistic model, Latent Dirichlet Allocation (LDA). The focus of the analysis is on literature and patents published since 2010 up to date, summing up altogether more than 25 000 references. We divide the references into eight topics: operating an electric vehicle, its control, motor operations, thermal management, battery module, battery technologies, electric vehicle (EV) infrastructure and charging EV. Because battery technologies are of strategic importance in technological competition for companies and relate to the areal raw material base, we take a more detailed look at this field. The results from publication analysis are presented for China, Europe, Japan and USA. The distribution of raw materials required for heavy duty vehicles shows interesting correlations with the national development strategies. China holds reserves and/or mine production for all key raw materials categories (battery, magnet and electric cabling) needed in heavy duty electric vehicles. In addition to having an extensive raw materials base, China has protected intellectual property rights in many areas thus defending the raw materials also by controlling the access to the technologies. USA has some raw material reserves and/or production among all three raw material categories also, but their global contribution is significantly lower. Japan, with very narrow natural resource base, has very limited patenting or scientific publishing in any of the studied sub-areas of heavy duty electric vehicle development.