Qi Xingtao, Huang Zhuqing, Zhang Ze, Wei Junchao, Yang Zhenyu
College of Chemistry, Nanchang University, No.999, Xuefu Road, Nanchang 330031, China.
College of Chemistry, Nanchang University, No.999, Xuefu Road, Nanchang 330031, China; School of Stomatology, Nanchang University, No.49, Fuzhou Road, Nanchang 330006, China.
J Colloid Interface Sci. 2024 Jun;663:716-724. doi: 10.1016/j.jcis.2024.02.188. Epub 2024 Feb 29.
The commercialization of lithium metal batteries (LMBs) is encountering significant challenges due to the electrolyte incompatibility and poor mechanical properties of polyolefin separators, as well as the hazardous growth of lithium dendrites at the anode. Simultaneously, the development of safe and environmentally-friendly separators has become a central focus in rechargeable battery technology. In this study, we introduce a novel Janus separator (CP@SiO), featuring a composite structure with cellulose paper (CP) as the base layer and electrospun polyvinylidene fluoride (PVDF) nanofibers as the top layer. The nanofibers are uniformly coated with mesoporous SiO nanoparticles through hydrogen bonding. The CP@SiO separator leverages its three-dimensional lithium-ion channels and rigid ceramic particles to enhance electrolyte retention and stabilize lithium metal anodes (LMA). Shielded by this separator, LMA exhibits an impressive cycling performance, enduring a current density of 2 mA cm for 350 h without short-circuiting, effectively doubling the cycle life compared to conventional PP separators. Furthermore, the Li/LiFePO cell utilizing the CP@SiO separator demonstrates a high capacity of 101 mAh·g at 5C, with 90 % capacity retention after 1000 cycles. This outstanding electrochemical performance is attributed to the compatible anode/separator interface and the effective inhibition of lithium dendrite growth. The research presented in this work capitalizes on a synergistic configuration design, offering a promising pathway towards the development of high-safety and advanced lithium-ion separators.
锂金属电池（LMBs）的商业化正面临重大挑战，这是由于聚烯烃隔膜存在电解质不相容性和机械性能差的问题，以及阳极锂枝晶的有害生长。同时，开发安全且环保的隔膜已成为可充电电池技术的核心焦点。在本研究中，我们引入了一种新型的双面隔膜（CP@SiO），其具有以纤维素纸（CP）为基层、电纺聚偏二氟乙烯（PVDF）纳米纤维为顶层的复合结构。纳米纤维通过氢键均匀地包覆有介孔SiO纳米颗粒。CP@SiO隔膜利用其三维锂离子通道和刚性陶瓷颗粒来增强电解质保留能力并稳定锂金属阳极（LMA）。在这种隔膜的保护下，LMA展现出令人印象深刻的循环性能，在2 mA cm的电流密度下持续350小时无短路，与传统PP隔膜相比，循环寿命有效延长了一倍。此外，使用CP@SiO隔膜的Li/LiFePO电池在5C时展现出101 mAh·g的高容量，在1000次循环后容量保持率为90%。这种出色的电化学性能归因于相容的阳极/隔膜界面以及对锂枝晶生长的有效抑制。本工作中提出的研究利用了协同配置设计，为开发高安全性和先进的锂离子隔膜提供了一条有前景的途径。
