Carboxymethyl cellulose as an artificial solid electrolyte interphase for stable zinc-based anodes in aqueous electrolytes
Phonnapha Tangthuam, Wathanyu Kao‐ian, Jinnawat Sangsawang, Catleya Rojviriya, Prae Chirawatkul, Jitti Kasemchainan, Falko Mahlendorf, Mai Thanh Nguyen, Tetsu Yonezawa, Soorathep Kheawhom
Abstract
Zinc (Zn) is viewed as a promising anode material for large-scale secondary batteries. However, due to parasitic reactions and uneven Zn distribution during repeated stripping/plating cycles, Zn anodes show inferior performance and stability. To overcome such drawbacks, carboxymethyl cellulose (CMC) as an artificial solid electrolyte interphase (ASEI) is fabricated on a Zn sheet and Zn-graphite composite anode. The roles of CMC-ASEI are examined using X-ray tomography, X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). Results show that the carboxyl group in CMC can regulate the flux and local concentration of Zn ions at the surface, allowing uniform Zn dissolution/deposition, and can suppress corrosion by reducing water activities on the anode’s surface. At 5 mA cm−2, the Zn-iodine battery having CMC-ASEI can cycle up to 2,000 cycles. This work provides a simple and scalable solution for advanced Zn anodes for Zn-based batteries.