Cui Jinghao, Meng Hongliang, Li Wei
Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control, College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China.
Polymers (Basel). 2025 Apr 28;17(9):1203. doi: 10.3390/polym17091203.
Cellulose-based separators with good electrolyte wettability and thermal stability have attracted extensive attention in the area of lithium metal battery (LMB) applications. However, their low mechanical strength in an electrolyte has seriously hindered their cycling performance of assembled LMB. Herein, a silane-crosslinked propionylated cellulose-based separator (PBF-GPTMS) was prepared. The resulting separator exhibited high wet strength (18.7 MPa) and electrolyte uptake (312 wt%). Molecular simulation revealed that Young's modulus of the silanized propionylated cellulose model was 14.64 GPa under EC/DMC/DEC conditions, which was higher than that of the propionylated cellulose model (6.89 GPa). In particular, the XPS spectra of the Li foil in the PBF-GPTMS-assembled battery after cycling suggested a lower amount of HF formed during cycling. Accordingly, the assembled Li/Separator/LiFePO cell showed excellent cycle performance with capacity retention of 94.5% after 300 cycles at 0.5 C and 93.6% after 160 cycles at 1 C, respectively. This idea would provide novel insights into the design of bio-based separators for long-life LMBs.
具有良好电解质润湿性和热稳定性的纤维素基隔膜在锂金属电池（LMB）应用领域引起了广泛关注。然而，它们在电解质中的低机械强度严重阻碍了其组装LMB的循环性能。在此，制备了一种硅烷交联的丙酰化纤维素基隔膜（PBF-GPTMS）。所得隔膜表现出高湿强度（18.7 MPa）和电解质吸收率（312 wt%）。分子模拟表明，在EC/DMC/DEC条件下，硅烷化丙酰化纤维素模型的杨氏模量为14.64 GPa，高于丙酰化纤维素模型（6.89 GPa）。特别地，循环后PBF-GPTMS组装电池中锂箔的XPS光谱表明循环过程中形成的HF量较低。因此，组装的Li/隔膜/LiFePO电池表现出优异的循环性能，在0.5 C下300次循环后容量保持率为94.5%，在1 C下160次循环后容量保持率分别为93.6%。这一想法将为长寿命LMBs的生物基隔膜设计提供新的见解。
