Advanced Liquid Metal Battery Technology
The primary limitation of renewable energy sources is the storage capacity of current batteries. Conventional batteries consist of solid materials that limit the amount of current that can flow through their components. These batteries do not have the ability to retain a charge for extended periods. However, a Massachusetts Institute of Technology team led by Professor Donald Sadoway may have discovered the solution to the problem. Liquid metal battery technology is the latest attempt to make a practical, long-term energy storage device for the intermittent energy generated by the sun and wind.
Anatomy of a Liquid Battery
A liquid metal battery has a rigid external housing with a positive and negative terminal just like a conventional battery. The difference is the internal components. A conventional battery has anodes and cathodes that consist of solid metal plates that are immersed in an electrolyte solution or gel. A liquid metal battery does not have these solid plates.
In the new battery, liquid metal is poured into the bottom of the container. An electrolyte solution consisting of a molten salt is added and finally another liquid metal is poured on top. The original prototypes used antimony, sodium sulfide and magnesium. The density of the three liquids keeps the solutions separated.
The Flow of Electricity
As with a standard battery, electrons flow from the anode through the electrolyte to the cathode and back depending upon whether the battery is being charged or discharged. During the charging process, the electrolyte expands and the molten metals contract. As the battery discharges its stored energy, the levels of the three molten solutions return to their original levels.
The advantage of a liquid metal battery is that there are no metal plates to corrode or disintegrate over time. This enables the newer battery to last longer. The flow of electrons is also easier, enabling the liquid metal battery to store more energy for an extended period. When this technology is commercialized, it is expected to provide a lower cost solution to the current limitations that hamper solar and wind power. These innovative batteries could make wind and solar the primary source of energy and reduce the reliance on fossil fuels.
Contact your local battery retailer for assistance and more information on locating the correct battery for your particular application.
