Fast Li-ion conductor additive toward high-rate lithium storage capacity for Li2ZnTi3O8 in lithium-ion batteries

A novel strategy to improve the ionic conductivity of the Li 2 ZnTi 3 O 8 (LZTO) anode is proposed by embedding exfoliation and exchange of Li + montmorillonite (MMT) in LZTO particles. Li 2 ZnTi 3 O 8 and montmorillonite (LZTO-MMT) composites are shown to induce not only a high concentration of Li + in the interlamellar channel of MMT but also a reduction in the distance for Li + migration to ensure fast and stable Li + diffusion kinetics. Furthermore, the thus obtained LZTO and 6 wt% MMT (LZTO-6MMT), composed of fast Li + conductor MMT, exhibits increased Li + conductivities, excellent high-rate Li + storage capacities, and significant improvement in cycle reversibility. The LZTO-6MMT electrode delivers 219.6 mAh g −1 at a current density of 1.0 A g −1 after 500 cycles and shows an excellent high-rate performance of 127.8 and 112.0 mAh g −1 over 2000 cycles at 5.0 and 10.0 A g −1 , respectively. X-ray photoelectron spectroscopy and ex situ Raman spectrum analyses suggest that the chemical bonds and crystal structure remain stable after multiple Li + intercalation/deintercalation processes. To the best of our knowledge, this is the first report on the introduction of fast-ion conductor MMT into LZTO and its application to lithium-ion batteries.