Wang Zijian, Yang Luyi, Liu Jiajie, Song Yongli, Zhao Qinghe, Yang Kai, Pan Feng
School of Advanced Materials, Peking University, Shenzhen Graduate School, Shenzhen 518055, People's Republic of China.
ACS Appl Mater Interfaces. 2020 Oct 28;12(43):48677-48683. doi: 10.1021/acsami.0c15015. Epub 2020 Oct 16.
Exhibiting superior safety features and low costs, solid-state sodium (Na)-ion batteries have been proposed as an attractive candidate for energy storage. However, the poor rate capability of solid-state batteries has limited their applications. In this work, an all-solid-state Na-ion battery is fabricated, delivering an unprecedented rate capability (60% capacity retention at a C-rate of 100 C with an areal loading of 1.5 mg cm), which far exceeds other reports so far. More importantly, it is further demonstrated that instead of the Na-ion conductivity of the solid electrolyte, the rate-limiting factors are determined to be charge-transfer resistance at electrode/solid electrolyte interfaces and lack of percolation pathways in the electrode, which can be optimized by tuning the electrode design and testing protocols.
固态钠离子（Na）电池具有卓越的安全特性和低成本，已被视为储能领域颇具吸引力的候选者。然而，固态电池较差的倍率性能限制了它们的应用。在这项工作中，制备了一种全固态钠离子电池，其展现出前所未有的倍率性能（在100 C的电流倍率下，面积负载为1.5 mg cm时容量保持率为60%），这远远超过了迄今为止的其他报道。更重要的是，进一步证明了速率限制因素并非固体电解质的钠离子电导率，而是电极/固体电解质界面处的电荷转移电阻以及电极中缺乏渗流路径，这些可通过调整电极设计和测试方案来优化。
