摘要
Li_(4)Ti_(5)O_(12)(LTO) anode material demonstrates superior cycling performance due to its stable spinel structure and high lithiation/de-lithiation potential.Herein,a novel energy-saving solid-phase synthesis route for LTO has been successfully designed,employing the cheap industrial intermediate product of metatitanic acid (HTO) as titanium source.Through the in-situ Fourier transform infrared spectroscopy (FTIR)and ex-situ X-ray diffraction (XRD),it is revealed for the first time that the amorphous crystal structure of HTO is more conducive for the Li+insertion,making it possible to prepare LTO at a relatively lower sintering temperature.Utilizing the dehydration carbonization reaction between glucose and sulfuric acid,an ingenious strategy of glucose pre-coating is adopted to avoid the generation of Li_(2)SO_(4) impurity caused by the residual sulfuric acid on the surface of HTO,which meanwhile enhances the conductivity and inhibits the particle growth of LTO.The obtained ALTO@C anode material consequently exhibits excellent electrochemical performance that 132.0 m Ah g^(-1)is remained even at 20 C,and ultra low decay rate of 0.015% per cycle is achieved during 1000 cycles at 2 C.Remarkably,LiCoO_(2)//ALTO@C full cell delivers conspicuous low-temperature property (130.7 m Ah g^(-1)at 0.5 C and almost no attenuation after 300 cycles under-20℃).
基金
financial support from the Major Science and Technology Projects of Sichuan Province(2019KJT0078)
the National Natural Science Foundation of China(51904193)
the Fundamental Research Funds for the Central Universities。
