Aqueous batteries with water-based electrolytes have been around since the birth of electrical energy storage. Lead-acid batteries with their sulfuric-acid / water electrolyte revolutionized the energy market a century ago, and are still going strong. However that said, the role of aqueous batteries in bulk energy storage is still limited. Organic polymer electrodes could help close this gap, perhaps with a polymer electrode for water-based batteries from Tohoku University in Japan.
How Aqueous Batteries Use Water in Their Electrolytes
Water-based batteries use water as the basis for their electrolytes, instead of the organic solvents in many conventional batteries. There are several distinct advantages in this approach, that attracted attention at Tohoku University:
- Water does not burn, unlike the organic solvents in lithium-ion batteries.
- Water is abundant, making aqueous batteries an affordable alternative.
- Electrodes may include abundant affordable zinc, iron, and manganese.
- Water is a great conductor, opening the door to more powerful batteries.
Polymer Electrodes in Water-Based Batteries
Organic redox, polymer electrodes could be just the trick for water-based batteries, but for one thing. This promising material is hydrophobic, meaning it repels water and does not mix with it.
The Japanese scientists concluded they needed a polymer that was hydrophilic instead, that attracts to water and even dissolves in it. They focused their attention on a polyallylamine polymer, comprising repeating hydrophilic allylamine units.
They then combined this compound with hydroquinone – an effective polymer stabilizer with a useful role in redox reactions – using condensation. This blend produced a novel polymer electrode for water-based batteries, with reversible and thorough charge storage properties.
Polymer is a plastic derivative. The scientists at Tohoku University knew they needed to include a recycling strategy in their proposal. They discovered their novel material easily reduced to its constituent materials using acid hydrolysis. This could be a break through for battery recycling!
More Information
Aqueous Redox Flow Battery Could Be The Key
A Polymer Electrolyte For All Batteries
