Batteries are very important to store the energy obtained from different sources like solar, wind etc. rechargeable li-ion batteries are used as energy storage devices. na-ion batteries are attractive beyond li-ion batteries due to low cost and earth-abundant precursors. different types of materials and electrolytes are made for na-ion battery application depending on the experience gained from li-ion batteries. there are mainly two types of cathode materials used for rechargeable sodium ion batteries: layer oxides and polyanionic compounds. layer oxides show high capacity, but they suffer from air stability and unsuitable for long term cyclability due to capacity loss causing from structural degradation over charging and discharging. polyanionic compounds show lower capacity compared to layered oxides but they show redox activity at higher voltage and stable for long term cyclability. sodium super ionic conductors (nasicon) are a group of polyanionic compounds with general formula (naymm’(xo4)3, y = 0-4; m, m’ = early and mid-transition metals mainly; x = p, si, s). we have synthesized a series of nasicon materials formulating na3+yv2-ymny(po4)3 (y = 0, 0.25, 0.5, 0.75, 1). from this series we have observed na3.75v1.25mn0.75(po4)3 shows highest capacity (105 ma h g-1 at c/10 current rate) and retain the capacity at higher current rates (1c and 5c current rates) compared to other materials of this series. then we substituted a little amount of redox inactive elements (al and mg) in nvmp to obtain a better material with capacity retention at high current rates. al-nvmp was observed as the best material with 96% capacity retention at 1c rate after 100cycles. the diffusion of na was observed higher for al-nvmp compared to unsubstituted one by galvanostatic intermittence titration technique. we are trying to dope with different elements in nasicon to get better capacity and high-capacity retention at high current rates.