The transition from fossil fuel-based power plants to clean, renewable energy sources is accelerating as both wind and solar power get cheaper and increasingly become cost-competitive with traditional power sources. The biggest stumbling block both energy sources face is that they cannot always supply power on demand but require the sun to shine and the wind to blow.
As a result, there is the need for effective ways to store electrical energy when it is generated for use when it is needed. Rechargeable batteries are increasingly viewed as the primary way to store energy, but it is not certain what kind of battery technology is best for storing energy on the grid. Lithium ion batteries are the mainstay for electric cars and they are gradually being used for the grid as well, but they are not necessarily the ideal solution.
Researchers at Stanford University have developed a new battery that uses a manganese salt dissolved in water to run a reversible chemical reaction that stores electrons in the form of hydrogen gas.
When current is introduced into the battery, the manganese sulfate dissolved in the water reacts to form manganese dioxide and hydrogen gas. The hydrogen gas can subsequently be used to generate electricity. When depleted, the battery can be recharged with additional current, which reacts the manganese dioxide with the water and replenishes the manganese sulfate. The researchers believe the recharging process can be repeated thousands of times over a decade lifespan.
The prototype battery is very low power, but the researchers believe it can be scaled up for utility use. They believe it can achieve much lower cost than lithium ion battery technology and be the ideal storage technology for a renewables-based electric grid.
Photo, posted December 21, 2012, courtesy of Ineke Huizing via Flickr.