Tian Yingkang, Chen Xinyang, Gao Xuejie, Wu Hanyan, Cheng Chen, Cai Shuiping, Ren Wenfeng, Yang Xiaofei, Sun Runcang
Center for Lignocellulosic Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
Division of Energy Storage, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
Molecules. 2023 Oct 2;28(19):6905. doi: 10.3390/molecules28196905.
The application of lithium metal batteries is limited by the drawbacks of safety problems and Li dendrite formation. Quasi-solid-state electrolytes (QSSEs) are the most promising alternatives to commercial liquid electrolytes due to their high safety and great compatibility with electrodes. However, Li dendrite formation and the slow Li diffusion in QSSEs severely hinder uniform Li deposition, thus leading to Li dendrite growth and short circuits. Herein, an eco-friendly and low-cost sodium lignosulfonate (LSS)-assisted PVDF-based QSSE is proposed to induce uniform Li deposition and inhibit Li dendrite growth. Li symmetric cells with 5%-LSS QSSE possess a high Li transfer number of 0.79, and they exhibit a long cycle life of 1000 h at a current density/areal capacity of 1 mA cm/5 mAh cm. Moreover, due to the fast electrochemical dynamics endowed by the improved compatibility of the electrodes and fast Li diffusion, the LFP/5%-LSS/Li full cells still maintain a high capacity of 110 mAh g after 250 cycles at 6C. This work provides a novel and promising choice that uses eco-friendly LSS as an additive to PVDF-based QSSE in Li metal batteries.
锂金属电池的应用受到安全问题和锂枝晶形成等缺点的限制。准固态电解质（QSSEs）因其高安全性以及与电极的良好兼容性，成为商用液体电解质最具潜力的替代品。然而，锂枝晶的形成以及锂在QSSEs中的缓慢扩散严重阻碍了锂的均匀沉积，进而导致锂枝晶生长和短路。在此，提出了一种环保且低成本的木质素磺酸钠（LSS）辅助的聚偏氟乙烯基QSSE，以诱导锂的均匀沉积并抑制锂枝晶生长。具有5%-LSS QSSE的锂对称电池具有0.79的高锂转移数，并且在1 mA cm/5 mAh cm的电流密度/面积容量下表现出1000 h的长循环寿命。此外，由于电极兼容性的改善和锂的快速扩散赋予了快速的电化学动力学，LFP/5%-LSS/Li全电池在6C下经过250次循环后仍保持110 mAh g的高容量。这项工作提供了一种新颖且有前景的选择，即在锂金属电池中使用环保的LSS作为聚偏氟乙烯基QSSE的添加剂。
