Rechargeable Sodium Aqueous Batteries: Novel Polymer Anodes

Due to the increasing need for large scale energy storage batteries have become a subject of great interest. Sodium aqueous batteries have the potential to deliver the kind of affordable grid scale energy storage needed to assist renewables penetration and power/price stability in the market. Since there are several well known positive electrodes available, more focus is dedicated so finding suitable negative electrodes for aqueous cells. Here we investigated polymer anodes due to their use of abundant elements, good performance, facile synthesis, and insolubility in aqueous electrolytes. Of the three base compounds chosen (anthraquinone, naphthalene diimide, and naphthalimide) only naphthalimide was successfully polymerized. However, the yield was small so the recovered monomers were tested instead. As a result, solubility issues were encountered in organic cell testing as expected, but in the end it was possible to make a fully reversible naphthalene diimide based cell with sodium manganese oxide as the positive electrode. The naphthalene diimide was not soluble in aqueous electrolyte and seemed to display optimistic results, so given the right choice of organic material polymerization may be unnecessary and these compounds seem promising for delivering reliable capacities affordably at a large scale.Electrical Engineering | Sustainable Energy Technolog