A nano-granular Sn impregnated NiTi alloy matrix anode for high voltage Li-ion pouch cells

Abstract

A well-characterized nano-granular Sn impregnated inactive NiTi alloy matrix has been synthesized through a viable and facile mill-heat method as a suitable anode matrix for Li-ion batteries. These polycrystalline grains of Sn in a NiTi alloy matrix exhibit an average size of ∼25 nm. The distinct advantages of Sn active site(s) hosting intercalated Li species are better electronic properties, favorable elastic features, in particular a Poisson ratio akin to the Sn-NiTi matrix, and cycling stability facilitating EV and HEV applications. The optimum anode composition Sn_0.70Ni_0.20Ti_0.10 vs. LiNi_1/3Mn_1/3Co_1/3O₂ : LiNi_0.5Mn_0.5O₂ composite cathode (wt% of 75 : 25), when used in a rolling in smart-design Li-ion pouch cell fabricated in the lab, yields a high voltage (>4.2 V) and its application was proven by the demonstration of running a toy-car with a load of 1.1 W h on a coarse bitumen road.