Abstract
Ever-increasing
energy needs demand for sustainable energy from natural materials. An abundant
natural material, protein possesses significant functional groups and great
potential for various energy storage applications. Firstly, the complex
compositions and structures of protein enabling the interaction with ions,
along with the excellent mechanical properties make it promising for fabricating
solid electrolytes. Via manipulating protein configuration, we fabricated an
advanced protein-based solid electrolyte showing good performances in ionic
conductivity, modulus and transference number (0.94). Secondly, unique
protein-coated ceramic nanofillers were created to enable faster ion-conduction
to enhance the poly(ethylene oxide)-based solid electrolyte. The resulting
composite electrolyte shows further improvement in ionic conductivity and
mechanical properties. Additionally, eco-efficient electrodes for advanced
batteries, such as Li-S battery, were studied. Simulation results prove that
the rich functional groups and unique spatial configuration of protein offer
strong polysulfide-trapping capability. Based on this, we developed a robust
and multifunctional protein-based binder for high-loading sulfur cathodes,
which deliver high areal capacity and stable cycling performance. Moreover, a
protein-functionalized conductive interlayer with assembled porous structure
was fabricated to effectively alleviate the shuttle effect and promote the
ion-transport. Consequently, the electrochemical performances of the Li-S
battery are notably improved.