In Situ Polymerized Methacrylate Based Electrolyte for Lithium‐Ion Batteries

Abstract We propose a novel approach for incorporating a polymer electrolyte into lithium‐ion batteries by employing a pre‐polymer electrolyte (PPE). The PPE consists of a conventional carbonate‐based electrolyte that also contains 2‐(trimethylsilyloxy)ethyl methacrylate (TSEMA) as a monomer and 2,2′‐azobis(2‐methylpropionitrile) (AIBN) as an initiator; this combination can form a gel‐type polymer electrolyte after being subjected to an aging process. The results confirm that aging the PPE at 45 °C leads to the successful formation of a gel‐type polymer in the cell through an in‐situ polymerization reaction. The in‐situ‐formed gel‐type polymer electrolyte demonstrates relatively low ionic conductivity compared to conventional electrolytes, but it can still be used in lithium‐ion batteries, since an ionic network is well developed on the electrode. The combination of lithium titanium oxide anode materials and this in‐situ‐formed gel‐type polymer electrolyte is compatible with high temperatures, as the cell cycled with the methacrylate‐based in‐situ‐formed electrolyte exhibits stable cycling retention after 50 cycles.