The power of water has been demonstrated in an aqueous, metal-free battery system engineered at Texas A&M University.

To sidestep lithium supply chain challenges, the water battery incorporates polymer-based cathodes and anodes, and water mixed with salts as the electrolyte. The redox-active non-conjugated radical polymers are promising candidates for water-based batteries because of their high discharge voltage and fast redox kinetics. This battery chemistry might be of value in overcoming potential shortages of metals such as cobalt and lithium, as well as in eliminating the potential for battery fires.

Researchers observed significant storage capacity in water-based batteries. Source: Texas A&M University

Redox reactions were analyzed by examining aqueous electrolytes of changing chao-/kosmotropic character using electrochemical quartz crystal microbalance with dissipation monitoring over different timescales. Experiments and simulations confirmed improved performance of the cathode in the presence of specific salts by measuring the influx of water and salt into the battery during operation.

The research published in Nature Materials reports a 1,000% difference in energy storage capacity, depending on the electrolyte selected, due to swelling effects.