Electrochemical Na-Storage Materials and Their Applications for Na-ion Batteries

Abstract

Oncoming large scale electric energy storage(EES) requires battery systems not only to have sufficient storage capac- ity but also to be cost-effective and environmentally friendly. Li-ion batteries for widespread EES applications may be limited due to the constraint of global lithium resource. From the considerations of available resources and environmental impact, Na-ion batter- ies have potential advantages as next generation secondary batteries and an alternative to Li-ion batteries. However, in the present state of the art, the Na-storage cathodes reported so far are still deficient both in energy density and power capability, while the car- bon and alloy anodes for Na-ion batteries have also the problem of insufficient cycling life for battery applications. This paper re- views briefly the recent advances in the development of Na-storage materials, analyses the different structural requirements for the materials in Li-ion and Na-ion batteries and discusses the possible strategies for development of low cost and pollution-free materi- als for rechargeable Na-ion batteries.