Dual Phase Li₄Ti₅O₁₂–TiO₂ Nanowire Arrays As Integrated Anodes For High-rate Lithium-ion Batteries

Journal Article · Tue Aug 19 04:00:00 UTC 2014 · Nano Energy, 9:383-391

DOI:https://doi.org/10.1016/j.nanoen.2014.06.032· OSTI ID:1170470

Liao, Jin; Chabot, Victor; Gu, Meng; Wang, Chong M.; Xiao, Xingcheng; Chen, Zhongwei

Lithium titanate (Li₄Ti₅O₁₂) is well known as a zero strain material inherently, which provides excellent long cycle stability as a negative electrode for lithium ion batteries. However, the low specific capacity (175 mA h g^-1) limits it to power batteries although the low electrical conductivity is another intrinsic issue need to be solved. In this work, we developed a facile hydrothermal and ion-exchange route to synthesize the self-supported dual-phase Li₄Ti₅O₁₂–TiO₂ nanowire arrays to further improve its capacity as well as rate capability. The ratio of Li₄Ti₅O₁₂ to TiO₂ in the dual phase Li₄Ti₅O₁₂–TiO₂ nanowire is around 2:1. The introduction of TiO₂ into Li₄Ti₅O₁₂ increases the specific capacity. More importantly, by interface design, it creates a dual-phase nanostructure with high grain boundary density that facilitates both electron and Li ion transport. Compared with phase-pure nanowire Li₄Ti₅O₁₂ and TiO₂ nanaowire arrays, the dual-phase nanowire electrode yielded superior rate capability (135.5 at 5 C, 129.4 at 10 C, 120.2 at 20 C and 115.5 mA h g^-1 at 30 C). In-situ transmission electron microscope clearly shows the near zero deformation of the dual phase structure, which explains its excellent cycle stability.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1170470
• Report Number(s): PNNL-SA-105729; 48170
• Journal Information: Nano Energy, 9:383-391, Journal Name: Nano Energy, 9:383-391
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory