Overcrowded Additive in Electrolyte and Crystalline Li2CO3 Artificial Solid Electrolyte Interphase on TiNb2O7 Anode Enable Long Lifespan Aqueous Lithium-Ion Batteries

• DOI: 10.1021/acsaem.3c00529
• Publication Date: 2023-05-02T15:30:48Z
• Authors: Haoyang Zhao; Jun Zhang; Tianqi Yang; Zheyu Jin; Xinping He; Zhongwei Wang; Yang Xia; Yao Wang; Xinyong Tao; Wenkui Zhang

Aqueous lithium-ion batteries (ALIBs) are attracting intense attention because of the intrinsic nonflammable nature aqueous electrolytes. However, its own narrow electrochemical window has led to numerous problems such as dissolution electrode materials, hydrogen evolution at anode, and poor cycling stability. Here, we report an "overcrowded electrolyte" using 1,4-dioxane additive, which lone pairs electrons on oxygen atom disrupt original water-hydrogen bonding network by forming intermolecular bonds, thereby inhibiting reaction (HER) decreasing water activity. Furthermore, a layer crystalline Li2CO3 is coated onto surface TiNb2O7 anode material supercritical fluid CO2 technology. The dense hydrophobic coating can serve physical protection, effectively blocks direct contact between electrolyte electrode. Under synergistic effect those two aspects, HER greatly suppressed interface stability enhanced. As result, LiMn2O4/TiNb2O7 full cells exhibit high initial coulomb efficiency 95% with capacity retention rate 92% over 500 cycles under 1 C rate. This work provides fundamental understanding interfacial chemistry ALIBs makes important step forward in development high-performance low-cost for practical applications.