Evans Jack D, Sun Yige, Grant Patrick S
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PU, U.K.
The Faraday Institution, Quad One, Becquerel Avenue, Harwell Campus, Didcot OX11 0RA, U.K.
ACS Appl Mater Interfaces. 2022 Aug 3;14(30):34538-34551. doi: 10.1021/acsami.2c03828. Epub 2022 Jul 22.
A porous, spray-deposited AlO-based separator was developed to enable the direct deposition of an electrode/separator/electrode Li-ion battery full cell assembly in a single operation. The optimized sprayed separator consisted of 50 nm AlO particles, 1 wt % poly(acrylic acid), and 5 wt % styrene-butadiene rubber, deposited from an 80:20 vol % suspension of water and isopropanol. Separators between 5 and 22 μm thick had consistent and similar porosity of ∼58%, excellent wettability, thermal stability to at least 180 °C, adequate electrochemical stability and high effective ionic conductivity of ∼1 mS cm at room temperature in an EC/DMC electrolyte, roughly double that of a conventional polypropylene separator. A sequentially deposited three-layer LiFePO/AlO/LiTiO full cell, the first of its kind, showed similar rate performance to an identical cell with a conventional polypropylene separator, with a capacity of ∼50 mAh g at 30 C. However, after cycling at 2 C for 400 cycles, AlO separator full cells retained 96.3% capacity, significantly more than conventional full cells with a capacity of 79.2% remaining.
开发了一种多孔的、喷雾沉积的基于AlO的隔膜，以实现电极/隔膜/电极锂离子电池全电池组件在单次操作中的直接沉积。优化后的喷雾隔膜由50 nm的AlO颗粒、1 wt%的聚丙烯酸和5 wt%的丁苯橡胶组成，由水和异丙醇体积比为80:20的悬浮液沉积而成。厚度在5至22μm之间的隔膜具有一致且相似的约58%的孔隙率、优异的润湿性、至少180°C的热稳定性、足够的电化学稳定性以及在EC/DMC电解液中室温下约1 mS cm的高有效离子电导率，约为传统聚丙烯隔膜的两倍。首个依次沉积的三层LiFePO/AlO/LiTiO全电池表现出与具有传统聚丙烯隔膜的相同电池相似的倍率性能，在30 C下容量约为50 mAh g。然而，在2 C下循环400次后，基于AlO隔膜的全电池保留了96.3%的容量，明显高于剩余容量为79.2%的传统全电池。
