Zhang Lu, Zhang Xiaohua, Tian Guiying, Zhang Qinghua, Knapp Michael, Ehrenberg Helmut, Chen Gang, Shen Zexiang, Yang Guochun, Gu Lin, Du Fei
Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), State Key Laboratory of Superhard Materials, College of Physics, Jilin University, 130012, Changchun, China.
Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education, Northeast Normal University, 130024, Changchun, China.
Nat Commun. 2020 Jul 13;11(1):3490. doi: 10.1038/s41467-020-17233-1.
Conventional lithium-ion batteries embrace graphite anodes which operate at potential as low as metallic lithium, subjected to poor rate capability and safety issues. Among possible alternatives, oxides based on titanium redox couple, such as spinel LiTiO, have received renewed attention. Here we further expand the horizon to include a perovskite structured titanate LaLiTiO into this promising family of anode materials. With average potential of around 1.0 V vs. Li/Li, this anode exhibits high specific capacity of 225 mA h g and sustains 3000 cycles involving a reversible phase transition. Without decrease the particle size from micro to nano scale, its rate performance has exceeded the nanostructured LiTiO. Further characterizations and calculations reveal that pseudocapacitance dictates the lithium storage process and the favorable ion and electronic transport is responsible for the rate enhancement. Our findings provide fresh impetus to the identification and development of titanium-based anode materials with desired electrochemical properties.
传统的锂离子电池采用石墨阳极,其工作电位低至金属锂,存在倍率性能差和安全问题。在可能的替代材料中,基于钛氧化还原对的氧化物,如尖晶石LiTiO,受到了新的关注。在此,我们进一步拓展视野,将钙钛矿结构的钛酸盐LaLiTiO纳入这一有前景的阳极材料家族。相对于Li/Li,该阳极的平均电位约为1.0 V,表现出225 mA h g的高比容量,并经历了3000次涉及可逆相变的循环。在未将粒径从微米级减小到纳米级的情况下,其倍率性能超过了纳米结构的LiTiO。进一步的表征和计算表明,赝电容决定了锂存储过程,良好的离子和电子传输是倍率提高的原因。我们的发现为识别和开发具有所需电化学性能的钛基阳极材料提供了新的动力。