Yang Zhiwei, Chen Ting, Chen Dequan, Shi Xinyu, Yang Shan, Zhong Yanjun, Liu Yuxia, Wang Gongke, Zhong Benhe, Song Yang, Wu Zhenguo, Guo Xiaodong
College of Chemical Engineering, Sichuan University, Chengdu, 610065, P. R. China.
School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, P. R. China.
Angew Chem Int Ed Engl. 2021 May 25;60(22):12539-12546. doi: 10.1002/anie.202102048. Epub 2021 Apr 26.
The continuous growth of the solid-electrolyte interface (SEI) and material crushing are the fundamental issues that hinder the application of Ge anodes in lithium-ion batteries. Solving Ge deformation crushing during discharge/charge cycles is challenging using conventional carbon coating modification methods. Due to the chemical stability and high melting point of carbon (3500 °C), Ge/carbon hybridization at the atomic level is challenging. By selecting a suitable carbon source and introducing an active medium, we have achieved the Ge/carbon doping at the atom-level, and this Ge/carbon anode shows excellent electrochemical performance. The reversible capacity is maintained at 1127 mAh g after 1000 cycles (2 A g (2-71 cycles), 4 A g (72-1000 cycles)) with a retention of 84 % compared to the second cycle. The thickness of the SEI is only 17.4 nm after 1000 cycles. The excellent electrochemical performance and stable SEI fully reflect the application potential of this material.
固体电解质界面（SEI）的持续生长和材料破碎是阻碍锗阳极在锂离子电池中应用的基本问题。使用传统的碳涂层改性方法来解决锗在充放电循环中的变形破碎具有挑战性。由于碳的化学稳定性和高熔点（3500°C），在原子水平上实现锗与碳的杂化具有挑战性。通过选择合适的碳源并引入活性介质，我们实现了原子级的锗/碳掺杂，这种锗/碳阳极表现出优异的电化学性能。在1000次循环（2 A g（2 - 71次循环），4 A g（72 - 1000次循环））后，可逆容量保持在1127 mAh g，与第二个循环相比保留率为84%。1000次循环后SEI的厚度仅为17.4 nm。优异的电化学性能和稳定的SEI充分体现了这种材料的应用潜力。
