Wang Chao, Wang Xianfen, Lin Chunfu, Zhao Xiu Song
Institute of Materials for Energy and Environment, College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, China.
School of Chemical Engineering, The University of Queensland, St Lucia, QLD, 4072, Australia.
Small. 2019 Oct;15(42):e1902183. doi: 10.1002/smll.201902183. Epub 2019 Aug 28.
High-rate performance flexible lithium-ion batteries are desirable for the realization of wearable electronics. The flexibility of the electrode in the battery is a key requirement for this technology. In the present work, spinel lithium titanate (Li Ti O , LTO) cuboid arrays are grown on flexible carbon fiber cloth (CFC) to fabricate a binder-free composite electrode (LTO@CFC) for flexible lithium-ion batteries. Experimental results show that the LTO@CFC electrode exhibits a remarkably high-rate performance with a capacity of 105.8 mAh g at 50C and an excellent electrochemical stability against cycling (only 2.2% capacity loss after 1000 cycles at 10C). A flexible full cell fabricated with the LTO@CFC as the anode and LiNi Mn O coated on Al foil as the cathode displays a reversible capacity of 109.1 mAh g at 10C, an excellent stability against cycling and a great mechanical stability against bending. The observed high-rate performance of the LTO@CFC electrode is due to its unique corn-like architecture with LTO cuboid arrays (corn kernels) grown on CFC (corn cob). This work presents a new approach to preparing LTO-based composite electrodes with an architecture favorable for ion and electron transport for flexible energy storage devices.
高倍率性能的柔性锂离子电池对于可穿戴电子产品的实现至关重要。电池中电极的柔韧性是该技术的关键要求。在本工作中,在柔性碳纤维布(CFC)上生长了尖晶石型钛酸锂(LiTi₂O₄,LTO)长方体阵列,以制备用于柔性锂离子电池的无粘结剂复合电极(LTO@CFC)。实验结果表明,LTO@CFC电极在50C时表现出极高的倍率性能,容量为105.8 mAh g,并且在循环过程中具有出色的电化学稳定性(在10C下1000次循环后容量损失仅2.2%)。以LTO@CFC作为阳极,以涂覆在铝箔上的LiNi₀.₅Mn₀.₅O₂作为阴极制备的柔性全电池在10C时显示出109.1 mAh g的可逆容量,具有出色的循环稳定性和良好的抗弯曲机械稳定性。观察到的LTO@CFC电极的高倍率性能归因于其独特的玉米状结构,即LTO长方体阵列(玉米粒)生长在CFC(玉米芯)上。这项工作提出了一种制备基于LTO的复合电极的新方法,该电极具有有利于柔性储能器件离子和电子传输的结构。