**6.6 Sodium based batteries**

Long life cycle, high efficiency, fast response, and high energy density characteristics, make these type of batteries to be suitable for on grid applications; but it require high temperature and extra insulation and active heating. Sodium nickel chlorides are used at small level in on grid and off grid applications, but with the research advancement their recharge power and life cycle can be enhanced and that will result in reduction of their cost [9].
