Key Takeaways
1. Traditional batteries use harmful acids and alkalis, posing environmental risks upon disposal.
2. Researchers have developed a safer water-based battery using neutral magnesium and calcium salts to prevent corrosion.
3. The new battery design features a covalent organic polymer for the negative electrode, allowing for high conductivity and fast ion storage.
4. The battery can deliver 2.2 volts and last over 120,000 charge cycles, potentially lasting more than 300 years.
5. The environmentally-friendly materials allow for safe disposal under strict regulations, though production scalability remains a challenge.
Traditional batteries depend on harsh and corrosive acids and alkalis, which can damage their internal parts and create serious risks for the environment when they are thrown away. To solve this problem, a team of researchers from the City University of Hong Kong and the Southern University of Science and Technology has created a safer, water-based battery option.
Innovative Design
This new battery design swaps out the dangerous liquids for an electrolyte made from neutral magnesium and calcium salts—these are minerals often found in tofu brine. By keeping the pH level at a neutral 7.0, this solution effectively stops internal corrosion from happening. For the negative electrode, the scientists developed Hexaketone-tetraaminodibenzo-p-dioxin, which is a type of covalent organic polymer. This structure resembles plastic and has electron-donating chemical connections, allowing for high conductivity and fast storage of divalent ions. The positive electrode is made from a Prussian blue analog, completing the system.
Impressive Performance
In testing, the full cell showed it could deliver a voltage range of 2.2 volts and specific energy of 48.3 watt-hours per kilogram, considering the total weight of the electrodes and the electrolyte. Most impressively, the battery can remain stable through 120,000 charge cycles at a specific current of 20 amperes per gram. If used with a daily charging schedule, this battery could theoretically last more than 300 years, which is significantly better than typical batteries that usually start to fail after just a few thousand cycles.
Environmental Benefits
The system achieves a specific capacity of 112.8 milliampere-hours per gram. Since the materials used are non-toxic to the environment, the battery can be disposed of safely under strict international regulations like the United States Resource Conservation and Recovery Act and ISO 14001. However, to bring this new battery to market, developers still face hurdles in scaling up the production of the organic polymer and boosting the overall energy capacity in limited spaces.
Source:
Link