Synthesis of hexa-methoxy-cyclo-tri-phosphazene and studies of its use as a flame retardant additive in Li-ion electrolytes

The flame retardant (FR) additive hexa-methoxy-cyclo-tri-phosphazene [NP(OCH/sub 3/)/sub 2/]/sub 3/ was synthesized using the literature procedures. The electrochemical and thermal properties of Li-ion electrolytes containing hexamethoxy-cyclo-tri-phosphazene additive were measured using cyclic voltammetry and accelerating rate calorimetery. The effect of this additive on the electrochemical performance of Li-ion cells was investigated in Li/sub x/C/Li/sub 1-x/Ni/sub 0.8/Co/sub 0.2/O/sub 2/ type coin cells.