A novel calcium-ion solid polymer electrolyte based on crosslinked poly(ethylene glycol) diacrylate

A solid polymer electrolyte (SPE) for calcium-ion conduction was produced and characterized. Poly(ethylene glycol) diacrylate was photocrosslinked under blue light in the presence of calcium salt to form a stable network with high thermal stability and promising conductivity. An ionic conductivity of 3.4 × 10−4 S/cm at 110 °C and 3.0 × 10−6 S/cm at room temperature was achieved, which is similar to early-stage lithium SPEs. The electrolytes evaluated under thermogravimetric analysis (TGA) remained stable up to temperatures of approximately 140 °C. XRD confirmed no salt precipitation within the polymer matrix, and Raman analysis indicated the complexation of the calcium ions to the PEGDA network. This study is a contribution towards suitable polymer electrolytes for solid-state calcium-ion batteries.