Sun Qiushi, Chen Xiao, Xie Jian, Xu Xiongwen, Tu Jian, Zhang Peng, Zhao Xinbing
State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University Hangzhou 310027 P. R. China
Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou 310027 P. R. China.
RSC Adv. 2019 Dec 19;9(72):42183-42193. doi: 10.1039/c9ra08677c. eCollection 2019 Dec 18.
Rechargeable lithium batteries with high-voltage/capacity cathodes are regarded as promising high-energy-density energy-storage systems. Nevertheless, these systems are restricted by some critical challenges, such as flammable electrolyte, lithium dendrite formation and rapid capacity fade at high voltage and elevated temperature. In this work, we report a quasi-solid-state composite electrolyte (QCE) prepared by polymerization reactions. The electrolyte consists of polymer matrix, inorganic filler, nonflammable plasticizers and Li salt, and shows a good thermal stability, a moderate ionic conductivity of 2.8 × 10 S cm at 25 °C, and a wide electrochemical window up to 6.7 V. The batteries with the QCE show good electrochemical performance when coupled with lithium metal anode and LiCoO or LiNiMnCoO cathodes. Pouch-type batteries with the QCE also exhibit stable cycling, and can tolerate abuse testes such as folding, cutting and nail penetration. The formed fluorides and phosphides from the plasticizers stabilize the interfaces between the QCE and electrodes, which enables stable cycling of Li metal batteries.
具有高压/高容量阴极的可充电锂电池被视为有前景的高能量密度储能系统。然而，这些系统受到一些关键挑战的限制，例如易燃电解质、锂枝晶形成以及在高电压和高温下容量快速衰减。在这项工作中，我们报道了一种通过聚合反应制备的准固态复合电解质（QCE）。该电解质由聚合物基体、无机填料、不可燃增塑剂和锂盐组成，具有良好的热稳定性，在25℃时离子电导率适中，为2.8×10 S cm，电化学窗口宽达6.7V。采用QCE的电池在与锂金属阳极和LiCoO或LiNiMnCoO阴极耦合时表现出良好的电化学性能。采用QCE的软包电池也表现出稳定的循环性能，并且能够耐受诸如折叠、切割和针刺等滥用测试。增塑剂形成的氟化物和磷化物稳定了QCE与电极之间的界面，这使得锂金属电池能够稳定循环。
