Solid-state synthesis of Li4Ti5O12 for high power lithium ion battery applications

• Published in: Journal of alloys and compounds 2013-09, Vol.570, p.144-149
• Main Authors: Han, Seung-Woo, Ryu, Ji Heon, Jeong, Joayoung, Yoon, Dang-Hyok
• Format: Article
• Language: English
• Subjects: Anatase; Applied sciences; Beads; Charge; Direct energy conversion and energy accumulation; Discharge; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy storage materials; Exact sciences and technology; High energy milling; Li4Ti5O12; Lithium ion battery; Lithium-ion batteries; Phase transformations; Solid-state reaction; Titanium dioxide; Zirconium dioxide
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2013.03.203

•High energy milling using 0.30 and 0.45mm beads for Li4Ti5O12 synthesis.•Synthesis of 162nm-sized pure Li4Ti5O12 by solid-state reaction.•Spray drying using fine starting materials to confer paste tackiness.•High capacity of 174mAh/g and adequate rate properties for high power LIBs applications. Li4Ti5O12 was synthesized by a solid-state reaction between Li2CO3 and anatase TiO2 for applications to high power lithium ion batteries. The starting materials underwent 6h of high energy milling using ZrO2 beads with two different sizes, 0.30 and 0.45mm. The smaller ZrO2 beads resulted in finer starting materials. Spray drying was also performed on the 0.30mm beads-treated particles to enhance the screen printability of a paste containing this powder. The finer starting materials showed a pure 162nm-sized Li4Ti5O12 due to the decreased diffusion length for a solid-state reaction, whereas the 0.45mm beads-treated starting materials resulted in a 242nm-sized Li4Ti5O12 phase containing 2wt.% of rutile TiO2 that had transformed from the anatase phase during heat treatment at 800°C for 3h. The finer Li4Ti5O12 showed higher charge capacity and better charge/discharge rates than the coarser particles, which highlights the importance of the primary particle size on the electrochemical properties of Li4Ti5O12 for high power applications. The fine Li4Ti5O12 particles had a discharge capacity of 174mAh/g at 0.1C and capacity retention of 80% at 10.0C.