290 J. Math. Fund. Sc i., Vo l. 50, No . 3, 2018, 290-302 Received November 6 th , 2017, Revised February 23 rd , 2018, Accepted for publication May 28 th , 2018. Copyright © 2018 Published by ITB Journal Publisher, ISSN: 2337-5760, DOI: 10.5614/j.math.fund.sci.2018.50.3.5 Lithium Titanate (LTO) Synthesis Through Solid State Reaction and Its Performance for LiFePO 4 /LTO Battery Viona Natalia 1 , Anggia Putri Gustami 1 , Fitria Rahmawati 1,3 , Witri Wahyu Lestari 1 & Agus Purwanto 2,3 1 Research Group of Solid State Chemistry & Catalysis, Chemistry Department, Sebelas Maret University, Jl. Ir. Sutami 36 A, Kentingan, Surakarta 57126, Indonesia 2 Chemical Engineering Department, Faculty of Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A, Kentingan Surakarta 57126, Indonesia 3 National Centre for Sustainable Transportation Technology, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia E-mail: fitria@mipa.uns.ac.id Abstract. Lithium titanate, LTO, was synthesized by solid state reaction with Li 2 CO 3 and TiO 2 powder as precursors. The result was characterized to investigate its crystal structure, phase content, cell parameters, surface morphology, electrical conductivity and its performance as electrode in a lithium ion battery. XRD analysis with Le Bail refinement showed that the prepared materials consisted of 4 phases of Li 4 Ti 5 O 12 , Li 2 TiO 3 , anatase TiO 2 and rutile TiO 2 . The surface morphology was still not homogeneous, with an average grain size of 0.533 ± 0.157 µm. When 1% LTO was mixed with graphite and used as anode of an LFP battery, it produced a specific capacity of 130.66 mAhg -1 with Coulombic efficiency of 94.2%. When the composition was 5% of the total anode powder, the specific capacity was 118.74 mAhg -1 and Coulombic efficiency was 92.72%. Keywords: LiFePO 4 ; lithium-ion battery; lithium titanate; solid state reactions. 1 Introduction The use of fossil energy can be reduced by utilizing energy sources such as wind and sunlight. However, to ensure that this energy supply is sustainable, those energy sources need to be connected to energy storage such as batteries [1,2]. Batteries have the ability to store chemical energy that can be converted to electrical energy at a high conversion efficiency and without gas emission [3]. The rechargeable lithium-ion batteries (LiBs) have been widely developed because of their high energy density, long life cycle, and high battery efficiency [4]. Graphite is mostly used as the anode material due to its low cost, its abundance, and high theoretical specific capacity of 372 mAhg -1 [5-7]. However, graphite can undergo volume expansion up to 10% during charging, which can cause severe structural destruction [8]. In addition, dendrites can be formed on the surface of graphite due to its low potential compared to lithium