Photocured polymer electrolytes for lithium-based batteries

We all desire a long-lasting, non-explosive, flexible and small lithium-ion battery (LIB) for our portable electronic devices and (future) electric vehicles. The use of a solid polymer as electrolyte, instead of a flammable solvent, is currently the most promising solution for thinner and safer LIBs. Poly(ethylene oxide)-based polymers (PEO) are widely used, even commercially, thanks to their good ability to transport lithium ions at temperatures over 60 °C. In our Lab, we focus on the structuring of classic −EO− based backbones by photo-polymerization, a fast, cost-effective and solvent-free technique. Solid polymer electrolytes (SPEs) based on different monomers/oligomers are prepared. By incorporating high amounts of plasticizers and lithium salts, outstanding ionic conductivities are obtained (σ > 10–4 S cm–1 at 20 °C) along with wide electrochemical stability window (>5 V vs. Li+/Li) as well as good interfacial stability. Besides, SPEs have remarkable morphological characteristics in terms of homogeneity, flexibility and robustness. All-solid lithium-based polymer cells show very good cycling behavior in terms of rate capability and stability over a wide range of operating temperatures, which confirms the promising prospects of photocured polymer electrolytes for practical application at ambient/sub-ambient temperatures.