Quasi-Solid-State Electrolyte Using an In Situ Click Reaction for Safety-Enhanced Lithium-Ion Batteries

Lithium-ion batteries with high energy density have been used widely as electrochemical energy storage devices to power mobile electronics, electric vehicles and large-sized energy storage systems. However, there are still safety concerns related to the highly flammable liquid electrolytes. As a highly safe electrolyte, we synthesized a three-dimensional quasi-solid-state electrolyte with high ionic conductivity of 2.1 × 10−3 S cm−1 using an in situ click reaction. Perfluoroether diacrylate with high oxidative stability was synthesized and used in in situ click reaction along with pentaerylythritol tetrakis(3-mercaptoptopionate) as the cross-linking agents. The lithium-ion cell composed of a graphite anode, a quasi-solid-state electrolyte and a LiNi0.6Co0.2Mn0.2O2 cathode was assembled, and its cycling characteristics and thermal stability were investigated. Our results reveal that the quasi-solid-state lithium-ion battery exhibits good capacity retention and superior thermal safety to conventional liquid electrolyte-based cells.