Fabrication of high Li:water molar ratio electrolytes for lithium-ion batteries

• 作 者: Miaofeng Huang Jiajie Yang Siron Zhen Chubin Wan Xiaoping Jiang Xin Ju
• 机 构: University of Science and Technology Beijing, Beijing 100083, China;Qilu University of Technology, S
• 出 处: 中国化学快报（英文版）
• 发表日期: 2021年2期
• 关键词: Aqueous electrolyte Wide potential window Aqueous Li-ion battery Solid electroly

Hydrous electrolytes with high electrochemical potentials were obtained by hydrating water molecules into solutes to form high Li:water molar ratio electrolytes (HMRE).Solid polyethylene glycol (PEG) were employed to enhance the molar ratio of Li+ to water in the electrolytes while reducing the consumption of Li-salt.The obtained mole ratio of Li+ to water molecules in the hydrous electrolytes was greater than 1∶1;however,the mass fraction of Li-salt was reduced to 61％ (approximately 5.5 mol/kg,based on water and PEG).Compared with that of water-in-salt electrolytes,the mass fraction of Li-salt could be remarkably reduced by adding solid PEG.The electrochemical stability of the electrolytes improved considerably because of the strong hydration of Li+ by the water molecules.A beneficial passivation effect,arising from the decomposition of the electrolyte,at a wide potential window was observed.