Revolutionizing Implantable Technology: Biocompatible Supercapacitors as the Future of Power Sources

Almost all implantable electronic medical devices (IEMDs) are powered by bulky Li-ion batteries (LIBs), limiting their miniaturization and lifespan advancements. In addition, LIBs contain toxic materials and flammable electrolytes that are dangerous if they leak into human organs. In this context, there is an urgent need to explore new approaches and concepts that can address the critical challenges of designing novel electrochemical energy storage systems and gain a mechanistic understanding of the phenomena taking place in diverse scenarios. This review summarizes recent advancements in biocompatible supercapacitors (B-SCs) as a power source for various IEMDs, offering a potential solution to these challenges. Different types of IEMDs and their power requirements are briefly discussed, along with challenges arising from energy storage systems and their applications in IEMDs. Given the importance of electrode materials in determining the electrochemical performance of B-SCs in terms of energy and power densities, different electrode materials and their developments are systematically reviewed. Finally, new insights are offered into potential opportunities and future prospects for the rational design of next-generation B-SCs.