High lithium storage performance of Ni_(0.5)Fe_(0.5)O_(1-x)Nx thin film with Nio-type crystal structure

The large voltage hysteresis of the NiO anode,which owes much to the intermediate product Li_(2)NiO_(2),is one of the main obstacles to its practical application in lithium-ion batteries.In this work,we show that the incorporation of Fe-and N-ions in the Nio lattice can suppress the formation of intermediate product Li_(2)NiO_(2)and thus greatly reduces the voltage hysteresis of the Nioanode from~1.2 to~0.9 V.In comparison with the pure Nio electrode,the Nio.5Feo.5O1-xNx anode exhibits significantly enhanced reversible specific capacity(959 mAh·g^(-1)at 0.3 A·g^(-1)),cycling stability(capacity retention of 96.1%at 100th cycle relative to the second cycle)and rate capability(442 at 10 A·g^(-1)).These results provide a practical method to enhance the lithium storage performance of the Nio anode and more importantly a new solution to the large voltage hysteresis of conversion-type anodes.