ABSTRACT
Electrical energy plays an important role in our everyday life as it can be stored and applied for general energy demands. Various types of electrochemical power sources are available for employing chemical compounds for conversion media and making use of redox reactions to yield or to store electrical energy. Generally, these power sources are divided into two types: energy storage (e.g., batteries and supercapacitors) and conversion (e.g., solar cell) systems. Considerable effort has been directed toward advanced technologies for more efficient energy storage systems in a wide range of applications, from microelectrochemical devices to portable electronics and even to transportation and grid storage. Among viable alternatives, batteries are preferable to fuel cells for specific applications that require moderate power density, and to supercapacitors applications that require higher energy density.
