Heterometallic Metal-Organic Cage Doped Peo Composite Electrolyte for Solid Lithium Ion Battery

Abstract

PEO (polyethylene oxide)-based electrolytes, which is characteristic of the advantages such as good film-forming properties, ease of mechanical processing, and non-reactivity with lithium metal, have been extensively studied. However, there still exist some certain issues related to energy and lifespan of all-solid-state lithium-ion batteries (ASSLIBs). The Cd-In cage [Cd2In3L2Cl5(H2O)9]Cl2 (L = 2,2',2''-(nitrilotris(methylene))tris(1H-benzo[d]imidazole-5-carboxylic acid) in this research can greatly disperse into PEO without significant agglomeration. The intrinsic cavities from the Cd-In cages form channels for lithium ion transport but inhibiting the transport of the corresponding counter anions, thereby protecting the electrode interface by reducing the interfacial reaction. For LFP||PEO-LiTFSI/Cage||Li cell at a fixed current density of 1.0 C, the specific capacity maintained a consistent level of 136 mA•h/g over a span of 100 cycles. This value was higher than those of cells prepared with pristine PEO electrolyte.

Keywords: heterometallic metal-organic cage, PEO composite electrolyte, solid lithium ion battery