Zhou Wanhai, He Jian, Zhu Ding, Li Jinchi, Chen Yungui
Institute of New-Energy and Low-Carbon Technology, Sichuan University, Chengdu, Sichuan 610065, China.
Engineering Research Center of Alternative Energy Materials & Devices, Ministry of Education, College of Materials Science and Technology, Sichuan University, Chengdu, Sichuan 610065, China.
ACS Appl Mater Interfaces. 2020 Aug 5;12(31):34931-34940. doi: 10.1021/acsami.0c08205. Epub 2020 Jul 23.
Zn-based aqueous batteries are enjoying the hotspots of worldwide research as their significant merits in economic cost and safety. However, the lack of a robust cathode (positive electrode) owning excellent rate ability, high capacity, and stability challenges their practical application. Herein, we propose hierarchical NiSe nanosheet arrays as a robust cathode toward high-performance Ni-Zn aqueous batteries. Attributed to anion exchange and Kirkendall effects, the nanosheet arrays are hierarchically constructed by NiSe nanoparticles and abundant mesopores, which fully expose the active sites and accelerate the electrode kinetics. This unique structure endows the NiSe electrode with remarkable specific capacity (245.1 mAh g) and extraordinary high-rate ability (maintains 58% at 72.8 A g) together with 10,000 cycles without any obvious capacity degeneration. As a result, based on the total active weight, our NiSe//Zn battery is capable of record-high power density (91.22 kW kg/639.1 mW cm), imposing energy density (328.8 Wh kg/2.303 mWh cm), and ultralong lifespan (only 8.3% capacity loss after 10,000 cycles), surpassing most of the aqueous batteries and supercapacitors recently reported. Moreover, this NiSe//Zn battery is also affordable (US$40 per kWh) and safe. These results open a new avenue for developing superdurable and ultrafast high-energy Ni-Zn batteries toward affordable and practical energy storage.
锌基水系电池因其在经济成本和安全性方面的显著优点而成为全球研究的热点。然而，缺乏具有优异倍率性能、高容量和稳定性的坚固正极（阳极）挑战了它们的实际应用。在此，我们提出将分级NiSe纳米片阵列作为高性能镍锌水系电池的坚固正极。由于阴离子交换和柯肯达尔效应，纳米片阵列由NiSe纳米颗粒和丰富的中孔分级构建而成，这充分暴露了活性位点并加速了电极动力学。这种独特的结构赋予NiSe电极显著的比容量（245.1 mAh g）和非凡的高倍率性能（在72.8 A g下保持58%），以及10000次循环且无明显容量衰减。因此，基于总活性重量，我们的NiSe//Zn电池能够实现创纪录的高功率密度（91.22 kW kg/639.1 mW cm²）、高能量密度（328.8 Wh kg/2.303 mWh cm²）和超长寿命（10000次循环后容量损失仅8.3%），超过了最近报道的大多数水系电池和超级电容器。此外，这种NiSe//Zn电池价格实惠（每千瓦时40美元）且安全。这些结果为开发超耐用、超快的高能量镍锌电池以实现经济实惠且实用的能量存储开辟了一条新途径。
