State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Resources, College of Materials Science and Engineering, Hainan University, Renmin Road No.58, Haikou, 570228, PR China; Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin, 300071, PR China.
State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Resources, College of Materials Science and Engineering, Hainan University, Renmin Road No.58, Haikou, 570228, PR China.
Carbohydr Polym. 2020 Oct 15;246:116622. doi: 10.1016/j.carbpol.2020.116622. Epub 2020 Jun 12.
With the advent of gel polymer electrolyte (GPE), a series of safety problems of lithium ion batteries have been resolved. However, poor self-standing property, the low ionic conductivity and Li transference number are still the obstacles that impede the practical application of GPE. Herein, a flexible and eco-friendly GPE is designed using allyl-modified cellulose with methylcellulose through simple UV curing. The crosslinked structure facilitates the integrity of GPE during use, and methylcellulose guarantees the high affinity to liquid electrolyte and improve interfacial compatibility. The specific polar functional groups (OH, OCH and COC) in GPE cooperate to enhance the lithium salt dissociation, anion immobilization and lithium ion transporting and enable the high Li transference number (0.902) and ion conductivity (4.36 × 10 S cm). The assembled Li/GPE/LiFePO coin cells possess high initial discharge capacity of 150.6 mA h g and a high capacity retention of 91.6 % after 100 cycles.
随着凝胶聚合物电解质（GPE）的出现，一系列锂离子电池的安全问题得到了解决。然而，较差的自支撑性能、较低的离子电导率和锂离子迁移数仍然是阻碍 GPE 实际应用的障碍。在此，通过简单的紫外光固化，使用烯丙基改性纤维素和甲基纤维素设计了一种灵活且环保的 GPE。交联结构有助于 GPE 在使用过程中的完整性，而甲基纤维素保证了与液体电解质的高亲和力，并提高了界面相容性。GPE 中的特定极性官能团（OH、OCH 和 COC）协同作用，增强了锂盐的解离、阴离子固定和锂离子传输能力，实现了高锂离子迁移数（0.902）和离子电导率（4.36×10Scm）。组装的 Li/GPE/LiFePO4 扣式电池具有较高的初始放电容量 150.6 mA h g-1和较高的容量保持率 91.6%，在 100 次循环后。
