Promoted kinetics and capacity on the Li2CuTi3O8/C anode by constructing a one dimensional hybrid structure for superior performance lithium ion batteries.

Abstract

Notably, spinel Li2CuTi3O8 with higher theoretical capacity inherits the characteristics of Li4Ti5O12, which is a promising anode material for lithium ion batteries with high energy density. However, the reversible migration of Cu2+ in Li2CuTi3O8 during the discharge process limits the diffusion of Li+, resulting in poor electrochemical performance. Space confinement is a desirable successful strategy to reduce the size of electroactive materials in return for getting improved kinetics and capacity for secondary ion batteries. Here, we develop a strategy by controlling the precursor of Li2CuTi3O8 in the walls of sulfonated polymer nanotubes, and the highly crosslinked copolymer network in the process of pyrolysis caused strong space confinement for the nanoparticles, which effectively prevented the agglomeration of Li2CuTi3O8 during the calcination process. The hybrid porous nanotubes consisting of Li2CuTi3O8 nanoparticles (5-50 nm) embedded in carbon nanotubes exhibit superior performance (402.8 mA h g-1 at 0.2 A g-1, 101 mA h g-1 at 10 A g-1 after 1000 cycles). This work provides a rapid and durable Li2CuTi3O8 electrochemistry, holding great promise in developing a practically viable Li2CuTi3O8 anode and enlightening material engineering in related energy storage and conversion areas.