Synthesis and electrochemical characterization of carbonaceous electrodes for potassium batteries

The transition towards renewable energy production is a process already underway, but its future growth depends on the development of cutting-edge technologies that are also environmentally friendly for the storage of electrical energy. One of these technologies, which is increasingly attracting the interest of researchers, is based on the unique properties of potassium. It could be used as a substitute for lithium in batteries to reduce their cost, environmental impact, and to make them better technologies to complement renewable sources. In this thesis work, anodes made of activated carbons derived from lignin have been studied. These anodes undergo a synthesis process that focuses on their economic sustainability and environmental impact. The obtained anodes possess promising characteristics for use in potassium batteries. They exhibit a high surface area (surface areas of over 2000m^2/g have been achieved) and low degree of graphitization. These anodes have demonstrated exceptional cyclic stability, maintaining good capacities even after a high number of cycles. The sample referred to as C2.5L-KOH, which is the most efficient, retained a capacity of 120 mAh/g after 600 cycles.