School of Chemistry and Chemical Engineering, Qingdao University , Qingdao, Shandong Province 266071, People's Republic of China.
Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences , Qingdao, 266101, People's Republic of China.
ACS Appl Mater Interfaces. 2017 Feb 1;9(4):3694-3701. doi: 10.1021/acsami.6b14352. Epub 2017 Jan 19.
High-voltage lithium-ion batteries have become a major research focus. As a major part of lithium batteries, the separator plays a critical role in the development of high-voltage lithium batteries. Herein, we demonstrated a sustainable and superior heat-resistant alginate nonwoven separator for high-voltage (5 V) lithium batteries. It was demonstrated that the resultant alginate nonwoven separator exhibited better mechanical property (37 MPa), superior thermal stability (up to 150 °C), and higher ionic conductivity (1.4 × 10 S/cm) as compared to commercially available polyolefin (PP) separator. More impressively, the 5 V class LiNiMnO (LNMO)/Li cell with this alginate nonwoven separator delivered much better cycling stability (maintaining 79.6% of its initial discharge capacity) than that (69.3%) of PP separator after 200 cycles at an elevated temperature of 55 °C. In addition, the LiFePO/Li cell assembled with such alginate nonwoven separator could still charge and discharge normally even at an elevated temperature of 150 °C. The above-mentioned fascinating characteristics of alginate separator provide great probability for its application for high-voltage (5 V) lithium batteries at elevated temperatures.
高压锂离子电池已成为主要研究焦点。作为锂离子电池的重要组成部分，隔膜在高压锂离子电池的发展中起着关键作用。在此，我们展示了一种可持续且具有优异耐热性的海藻酸钠无纺隔膜，用于高压（5 V）锂电池。结果表明，与市售的聚烯烃（PP）隔膜相比，所得的海藻酸钠无纺隔膜具有更好的机械性能（37 MPa）、更优异的热稳定性（高达 150°C）和更高的离子电导率（1.4×10 S/cm）。更令人印象深刻的是，在 55°C 的高温下经过 200 次循环后，使用这种海藻酸钠无纺隔膜的 5 V 级 LiNiMnO（LNMO）/Li 电池比使用 PP 隔膜（69.3%）具有更好的循环稳定性（保持其初始放电容量的 79.6%）。此外，即使在 150°C 的高温下，使用这种海藻酸钠无纺隔膜组装的 LiFePO/Li 电池仍能正常充电和放电。海藻酸钠隔膜的上述迷人特性为其在高温下用于高压（5 V）锂电池提供了很大的可能性。
