||Implantable device is promising for healthcare and bio-industry in future. However, there are many challenges induced by bio-compatibility and toxicity. Therefore, development of materials should be preceded in these problems. Main component of conventional electrodes are transition metal oxide and carbon materials. But transition metal oxide has poor bio-compatibility because of inflammatory reaction and toxicity in the body, while carbon materials have bio-inert property. Especially, in aqueous electrolyte like body fluids, The carbon materials show superior morphology and structure stability. In this study, we proposed pyroprotein materials derived by silk protein with abundant heteroatoms, which can store alkali-ion in body through surface redox reaction of electrode. Additionally, these materials demonstrated excellent bio-compatibility, mechanical properties, and electrochemical performance.