Batteries are an essential part of everyday life, powering many useful devices and applications. The rechargeable lithium-ion (Li-ion) battery has revolutionised the technology industry and transformed global communication. As a result, it is now considered the technology of choice for energy storage in a variety of portable electronic devices. However, its application in large-scale storage applications is limited. The sodium-ion (Na-ion) battery is becoming increasingly popular for large-scale energy storage, particularly in the field of renewable energy. In contrast to Li-ion batteries, the chemical processes taking place in Na-ion batteries are poorly understood. Moreover, the materials used as cathodes, anodes and electrolytes in Na-ion batteries are under constant development. The proposed research aims to synthesise and characterise a series of novel Na-based compounds for use in Na-ion batteries. Characterisation techniques capable of probing both the long- and short-range order of a material will be used, including X-ray and neutron powder diffraction and solid-state nuclear magnetic resonance (NMR).