New graphene derivative advances the supercapacitor’s energy storage advantage With a new scalable graphene derivative, researchers hope to create supercapacitors that can store comparable energy to batteries while also offering superior rapid charging capabilities. Energy © Dr. Me, Shutterstock The world is in the midst of an energy transition. But as we move away from fossil fuels and towards renewable sources, we must address the challenge of energy storage. One possible solution is the supercapacitor. According to ScienceDirect, supercapacitors are “electrochemical energy storage devices that store and release energy by reversible adsorption and desorption of ions at the interfaces between electrode materials and electrolytes.” One advantage supercapacitors have over other energy storage solutions, such as batteries, is a significantly longer lifespan. Whereas batteries can typically handle between 2 000 and 3 000 charge/discharge cycles, supercapacitors can handle more than 1 million rapid charges – resulting in a major reduction in materials and costs. Despite their charge/discharge advantage, supercapacitors cannot compete with the battery’s far superior energy storage capabilities. But this could soon change, thanks to a new graphene derivative being developed by the EU-funded UP2DCHEM project. “By replacing activated carbon with a novel graphene derivative, we can create supercapacitors capable of storing comparable energy to a typical battery, while maintaining superior, rapid charging capabilities,” explains Michal Otyepka, head of the nanomaterial division of the Czech Advanced Technology and Research Institute, part of Palacký University Olomouc, which hosted the UP2DCHEM project. Scaling up Graphene is a thin layer of pure carbon, tightly packed and bonded in a hexagonal honeycomb lattice. “It is widely regarded as a ‘wonder material’ because it is endowed with an abundance of astonishing traits – from being the thinnest known compound and the best known conductor,” reports Graphene-info. “It also has amazing strength and light absorption traits and is even considered ecologically friendly and sustainable.” It was these traits that attracted Otyepka to the material in the first place. In a previous project, Otyepka designed new functional materials derived from graphene, one of which showed very promising results in labs. In the UP2DCHEM project, which was supported by the European Research Council, he aimed to upscale the material’s synthesis from milligrams to kilos and to verify its utilisation in energy storage devices. “In the laboratory, we normally prepare and test rather small samples, often quantities of less than a gram,” remarks Otyepka. “However, commercial partners need orders of magnitude larger quantities, more than a half a kilogram, to assemble device prototypes.” Yet scaling up from small to large quantities proved more challenging than expected, especially as the synthesis requires one chemical to be used as an airbag propeller. “Initially, it was quite hard to find a company willing to collaborate on such a potentially ‘explosive’ project,” adds Otyepka. Ultimately, the project found a company that managed the synthesis, allowing Otyepka to confirm that it is possible to synthetise such quantities and that the material still exhibits the required properties under these conditions and volumes. Not only does this finding allow Otyepka to further optimise the synthesis, it has also opened the door to supercapacitor devices and further evolution of the project. “We are now working to transform these new materials into devices that contribute to solving the ever-increasing demand for stable, cheap and sustainable energy,” concludes Otyepka. Researchers are currently collaborating with several companies and universities to create graphene-based supercapacitor prototypes. Keywords UP2DCHEM, graphene, supercapacitor, energy storage, battery, batteries, charging, sustainable energy
