Electrochemistry and Solid-State Chemistry of NaMeO_2 (Me = 3d Transition Metals)

摘要

Sodium 3d transition metal oxides for Na-ion batteries have attracted attention of battery researchers because of their new chemistries and abundant material resources in the earth. Some companies have also developed Na-ion battery prototypes mainly consisting of a layered oxide as a positive electrode material and hard carbon as the negative one for practical use. In this article, progress of Na-containing layered transition-metal oxides is reviewed in terms of fundamental chemistry and technology aspects for future batteries as a post Li-ion battery. To realize practical positive electrode materials is still challenging and the practical issues are discussed. In this context the authors propose strategies for designing layered transition-metal oxide materials toward realization of practical Na-ion batteries.