Tan Liwen, Li Zhenxing, Shi Ran, Quan Fengyu, Wang Bingbing, Ma Xiaomei, Ji Quan, Tian Xing, Xia Yanzhi
School of Materials Science and Engineering, Qingdao University, Qingdao 266071, China.
State Key Laboratory of Bio-Fibers and Eco-Textiles, Collaborative Innovation Center of Marine Biobased Fiber and Ecological Textile Technology, Institute of Marine Biobased Materials, Qingdao University, Qingdao 266071, China.
ACS Appl Mater Interfaces. 2020 Aug 26;12(34):38175-38182. doi: 10.1021/acsami.0c10630. Epub 2020 Aug 17.
The membrane is one of the key inner parts of lithium-ion batteries, which determines the interfacial structure and internal resistance, ultimately affecting the capacity, cycling, and safety performance of the cell. In this article, an alginate-based fiber composite membrane was successfully fabricated from cellulose and calcium alginate with flame-retardant properties via a traditional papermaking process. In the membrane, the calcium alginate plays a bridging role and the cellulose acts as a filler. After 100 cycles, lithium-ion batteries by the alginate-based fiber separator exhibited better capacity retention ratios (approximately 90%) compared with those of commercial PP separators. Furthermore, the alginate-based fiber separator demonstrated fine thermal stability and electrochemical properties, showing a stable charge-discharge capability and no hot melt shrinkage at higher temperatures, which is a breakthrough in improving the safety of the cell. This research affords a new way for the large-scale fabrication of safe lithium-ion battery separators.
隔膜是锂离子电池关键的内部部件之一，它决定了界面结构和内阻，最终影响电池的容量、循环性能和安全性能。在本文中，通过传统造纸工艺成功制备了一种具有阻燃性能的基于海藻酸钠的纤维复合隔膜，该隔膜由纤维素和海藻酸钠制成。在隔膜中，海藻酸钠起到桥接作用，纤维素作为填料。经过100次循环后，与商用聚丙烯隔膜相比，基于海藻酸钠的纤维隔膜的锂离子电池表现出更好的容量保持率（约90%）。此外，基于海藻酸钠的纤维隔膜表现出良好的热稳定性和电化学性能，在较高温度下显示出稳定的充放电能力且无热熔收缩现象，这在提高电池安全性方面是一个突破。该研究为大规模制备安全的锂离子电池隔膜提供了一种新方法。
