School of Chemical Engineering, Northwest University , Xi'an, Shaanxi 710069, China.
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Collaborative Innovation Center of Advanced Microstructures, Institute of Materials Engineering, Nanjing University , Nanjing 210093, China.
ACS Appl Mater Interfaces. 2017 Aug 2;9(30):25250-25256. doi: 10.1021/acsami.7b04635. Epub 2017 Jul 20.
The energy and power densities of rechargeable batteries urgently need to be increased to meet the ever-increasing demands of consumer electronics and electric vehicles. Alloy anodes are among the most promising candidates for next-generation high-capacity battery materials. However, the high capacities of alloy anodes usually suffer from some serious difficulties related to the volume changes of active materials. Porous supports and nanostructured alloy materials have been explored to address these issues. However, these approaches seemingly increase the active material-based properties and actually decrease the electrode-based capacity because of the oversized pores and heavy mass of mechanical supports. In this study, we developed an ultralight porous nickel to scaffold with high-capacity SnSb alloy anodes. The porous-nickel-supported SnSb alloy demonstrates a high specific capacity and good cyclability for both Li-ion and Na-ion batteries. Its capacity retains 580 mA h g at 2 A g after 100 cycles in Li-ion batteries. For a Na-ion battery, the composite electrode can even deliver a capacity of 275 mA h g at 1 A g after 1000 cycles. This study demonstrates that combining the scaffolding function of ultralight porous nickel and the high capacity of the SnSb alloy can significantly enhance the electrochemical performances of Li/Na-ion batteries.
可充电电池的能量和功率密度迫切需要提高，以满足消费电子产品和电动汽车日益增长的需求。合金负极是下一代高容量电池材料最有前途的候选材料之一。然而，合金负极的高容量通常会遇到一些与活性材料体积变化相关的严重问题。多孔支架和纳米结构的合金材料已经被探索来解决这些问题。然而，由于过大的孔和机械支架的巨大质量，这些方法似乎提高了基于活性材料的性能，实际上降低了基于电极的容量。在本研究中，我们开发了一种超轻多孔镍支架，用于高容量 SnSb 合金负极。多孔镍支撑的 SnSb 合金在锂离子和钠离子电池中表现出高比容量和良好的循环稳定性。在锂离子电池中，其容量在 2 A g 下经过 100 次循环后保留 580 mA h g。对于钠离子电池，复合电极在 1 A g 下经过 1000 次循环后甚至可以提供 275 mA h g 的容量。本研究表明，将超轻多孔镍的支架功能与 SnSb 合金的高容量结合起来，可以显著提高锂离子/钠离子电池的电化学性能。
