Synthesis and electrochemical performance of Li₄Ti₅O₁₂/TiO₂/C nanocrystallines for high-rate lithium ion batteries

Abstract

composites, which can be attributed to high grain boundary density, abundant phase interfaces and in situ formed carbon, for storing extra lithium ions, enhancing rapid lithium insertion/extraction kinetics and improving electron transport rate. Corresponding 14As is well known, the volumic capacity is an important parameter for the practical application of Li 4 Ti 5 O 12 -based materials 37,38 . The capacities of the samples in this work are addressed not only by weight dimensionality (mAh g -1 ) but also by volume (mAh cm -3 ). The densities of the pure composites are calculated to be 3.41, 2.97, 3.52 and 3.26 g cm -3 , respectively. The initial three charge-discharge cycle profiles for pure composite electrodes with a current rate of 0. 5 C (1 C= 175 mA g -1 ) are shown in Fig 7a-d. Agree well with the result of CV curves (Fig. 6), two long flat plateaus at about 1.51 and 1.62 V are observed for all the samples due to the typical lithium insertion/extraction processes of Li 4 Ti 5 O 12 . Moreover, the voltage plateaus at around 1.98 and 1.72 V are verified as the lithium ion insertion/extraction reaction of anatase TiO 2 . 5 The initial discharge capacities of pure composites are 134, 157, 144 and 170 mAh g −1 , corresponding to 455, 466, 506 and 554 mAh cm -3 , respectively. The charge-discharge profiles of all samples are nearly invariable after the second cycle. The reversible capacities of the third cycle for pure composites are approximately 87, 119, 117 and 143 mAh g −1 , corresponding to 297, 353, 411 and 466 mAh cm -3 , respectively.The higher specific capacity of Li 4 Ti 5 O 12 /TiO 2 /C composite is contributed by relatively high theoretical capacity of anatase TiO 2 and carbon, and the extra lithium storage derived from phase interfaces.

Fabrication of Li4Ti5O12-TiO2 Nanosheets with Structural Defects as High-Rate and Long-Life Anodes for Lithium-Ion Batteries

“…6c, including LTO-TiO 2 nanowire arrays 50 , copper-doped LTO-TiO 2 nanosheets 24 , rutile-TiO 2 coated LTO 23 , petal-like LTO-TiO 2 nanosheets 51 , amorphous carbon coated LTO-TiO 2 20 , hierarchical LTO-TiO 2 microsphere 52 , LTO/rutile-TiO 2 composite 53 and LTO-TiO 2 -C nanocrystallines 12 . It is clear that the LTO-RT-AT possesses ultrahigh capacities and remarkable rate capability at various rates.…”

“…A variety of strategies, therefore, have been developed to improve the electrochemical performance of LTO, such as reducing the particle size 9 , doping with foreign atoms 10, 11 and coating with carbon materials 12 . However, as demonstrated in previous studies, it still remains a great challenge to concurrently obtain the LTO anode materials with both high energy density and high power density.…”

Challenges of Spinel Li4Ti5O12 for Lithium‐Ion Battery Industrial Applications

“…Zhu et al [129] compared the difference among Li 4 Ti 5 O 12 /TiO 2 /C, Li 4 Ti 5 O 12 /TiO 2 , Li 4 Ti 5 O 12 /C and pure Li 4 Ti 5 O 12 . Zhu et al [129] compared the difference among Li 4 Ti 5 O 12 /TiO 2 /C, Li 4 Ti 5 O 12 /TiO 2 , Li 4 Ti 5 O 12 /C and pure Li 4 Ti 5 O 12 .…”

Li4Ti5O12−TiO2 Composite Coated on Carbon Foam as Anode Material for Lithium Ion Capacitors: Evaluation of Rate Performance and Self‐Discharge

“…prepared LTO‐TO nanosheets anchored on reduced graphene oxide as self‐supporting electrodes to store Li + ions with a capacity of 86 mAh g −1 at 100 C . Zhu and coworkers reported a LTO/TO/C nanocrystalline composite which delivered a discharge capacity of 88 mAh g −1 at 30 C . However, these studies mainly focus on the improvement of the rate capacity.…”