Supercapacitors already have many practical applications, such as in power tools, harbour cranes, and hybrid vehicles. Researchers are looking at an increasing number of application possibilities. In intelligent electricity grids, known as smart grids, they ensure output stability, secure grid reserves and regulate voltage. “Using this technology to manage electricity grids is extremely promising,” explains MEET researcher, Dr Andrea Balducci, coordinator of the project. “To introduce it effectively, we still need to increase the energy density of the supercapacitors.”
The key to higher energy densities whilst still maintaining safety standards is in the electrolyte - the ion conductor. The key focus of this “Innovative Electrochemical Supercapacitors” (IES) joint project is to develop an electrolyte solution based on a mixture of ionic liquids and organic carbonates. Ionic liquids have, among others things, the advantage that they are non-flammable and have high chemical and thermal stability. Scientists will also investigate the composition of the electrolyte required for the supercapacitors to be used at high operating voltages and extreme temperatures. “It may also be necessary to adapt the materials used in the supercapacitors to suit the new electrolyte,” says Dr Balducci.
The two technologies, supercapacitors and batteries, are closely related, however, there are significant differences in the power and energy density of both systems. Supercapacitors have a comparatively lower energy density than batteries, but the power density of supercapacitors is significantly higher. As a result, they can be charged and discharged within a few seconds, which means that they provide energy quickly and have a long service life of more than 500,000 charging cycles.