Kweon Hyukmin, Kim-Shoemaker William
Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA.
BenSci Inc., 2321W 10th Street, Los Angeles, CA 90006, USA.
Polymers (Basel). 2022 Oct 16;14(20):4359. doi: 10.3390/polym14204359.
To mitigate lithium dissolution and polysulfide shuttle effect phenomena in high-energy lithium sulfur batteries (LISBs), a conductive, flexible, and easily modified polymer composite layer was applied on the anode. The polymer composite layer included polyaniline and functionalized graphite. The electrochemical behavior of LISBs was studied by galvanostatic charge/discharge tests from 1.7 to 2.8 V up to 90 cycles and via COMSOL Multiphysics simulation software. No apparent overcharge occurred during the charge state, which suggests that the shuttle effect of polysulfides was effectively prevented. The COMSOL Multiphysics simulation provided a venue for optimal prediction of the ideal concentration and properties of the polymer composite layer to be used in the LISBs. The testing and simulation results determined that the polymer composite layer diminished the amount of lithium polysulfide species and decreased the amount of dissolved lithium ions in the LISBs. In addition, the charge/discharge rate of up to 2.0 C with a cycle life of 90 cycles was achieved. The knowledge acquired in this study was important not only for the design of efficient new electrode materials, but also for understanding the effect of the polymer composite layer on the electrochemical cycle stability.
为了减轻高能锂硫电池（LISB）中的锂溶解和多硫化物穿梭效应现象，在阳极上施加了一层导电、柔性且易于改性的聚合物复合层。该聚合物复合层包括聚苯胺和功能化石墨。通过在1.7至2.8 V下进行高达90次循环的恒电流充放电测试以及使用COMSOL Multiphysics模拟软件，研究了LISB的电化学行为。在充电状态下未出现明显的过充电现象，这表明多硫化物的穿梭效应得到了有效抑制。COMSOL Multiphysics模拟为优化预测LISB中使用的聚合物复合层的理想浓度和性能提供了一个平台。测试和模拟结果表明，聚合物复合层减少了LISB中多硫化锂物种的数量，并降低了溶解锂离子的数量。此外，实现了高达2.0 C的充放电速率以及90次循环的循环寿命。本研究中获得的知识不仅对于设计高效的新型电极材料很重要，而且对于理解聚合物复合层对电化学循环稳定性的影响也很重要。
