A High‐Temperature Na‐Ion Battery: Boosting the Rate Capability and Cycle Life by Structure Engineering
Yanping Zhou, Xianghua Zhang, Xianghua Zhang, Yanjing Liu, Xinxin Xie, Xianhong Rui, Xiong Zhang, Xiong Zhang, Yuezhan Feng, Xiaojun Zhang, Xiaojun Zhang, Yan Yu, Kama Huang
Abstract
Abstract High‐temperature sodium ion batteries (SIBs) have drawn significant heed recently for large‐scale energy storage. Yet, conventional SIBs are in the depths of inferior charge/discharge efficiency and cyclability at elevated temperatures. Rational structure design is highly desirable. Hence, a 3D hierarchical flower architecture self‐assembled by carbon‐coated Na 3 V 2 (PO 4 ) 3 (NVP) nanosheets (NVP@C‐NS‐FL) is fabricated via a microwave‐assisted glycerol‐mediated hydrothermal reaction combined with a post heat‐treatment. The growth mechanism of NVP@C‐NS‐FL is systematically investigated, by forming a microspherical glycerol/polyglycerol‐NVP complex initially and then converting into flower‐like architecture during the subsequent annealing at a low temperature ramping rate. Benefiting from the integrated structure, fast Na + transportation, and highly effective heat transfer, the as‐obtained NVP@C‐NS‐FL exhibits an excellent high‐temperature SIB performance, e.g., 65 mAh g −1 (100 C) after 1000 cycles under 60 °C. When coupled with NaTi 2 (PO 4 ) 3 anode, the full cell can still display superior power capability of 1.4 kW kg −1 and long‐term cyclability (2000 cycles) under 60 °C.