Polymer-templated mesoporous lithium titanate microspheres for high-performance lithium batteries

Abstract

The spinel Li₄Ti₅O₁₂ (LTO) is a promising lithium ion battery anode material with the potential to supplement graphite as an industry standard, but its low electrical conductivity and Li-ion diffusivity need to be overcome. Here, mesoporous LTO microspheres with carbon-coatings were formed by phase separation of a homopolymer from microphase-separated block copolymers of varying molar masses containing sol-gel precursors. Upon heating the composite underwent a sol-gel condensation reaction followed by the eventual pyrolysis of the polymer templates. The optimised mesoporous LTO microspheres demonstrated an excellent electrochemical performance with an excellent specific discharge capacity of 164 mA h g^-1, 95% of which was retained after 1000 cycles at a C-rate of 10.