We have developed a new high-capacity hydrogen titanium oxide material (H₂Ti₁₂O₂₅) for the negative electrodes of lithium ion secondary batteries in collaboration with Ishihara Sangyo Kaisha, Ltd. (ISK). The developed material exhibits the same voltage (approximately 1.55 V vs. Li/Li⁺) as and a higher charge-discharge capacity per mass of oxide (225 mAh/g against 175 mAh/g) than lithium titanate (Li₄Ti₅O₁₂) presently used in negative electrodes. In addition, because the hydrogen atoms in the material form a skeletal structure due to hydrogen bonding, the structure of the material is stable, and is not affected by the lithium insertion and extraction reactions during charging and discharging. The new material displayed an excellent charge-discharge cyclic performance equivalent to that of the conventional lithium titanate, while it maintained a high capacity of over 200 mAh/g even after 50 cycles. Accordingly, the developed H₂Ti₁₂O₂₅ is expected to be one of the high-voltage oxide negative electrodes in advanced lithium-ion batteries.