The American company Fourth Power has developed a thermal battery capable of storing energy in molten tin at temperatures up to 2400°C. Engineers estimate that the new technology will be ten times cheaper than lithium-ion batteries and could even compete with gas power plants.
Unlike conventional chemical batteries, the Fourth Power battery uses a two-stage process: during the day, excess electricity from solar panels heats up graphite blocks, and when needed, the system passes liquid tin through them. The superheated metal emits light, which thermophotovoltaic cells capture and convert back into electricity.
The main advantages of the innovation are low cost, durability, and high energy density. Experts predict the cost of storage will be around $25 per kilowatt-hour, significantly lower than current market solutions. Furthermore, the battery is designed for daily cycles lasting eight hours or more, and energy losses due to special insulation do not exceed 1% per day.
The company has already raised $20 million to create the first demonstrator battery with a capacity of 1 megawatt-hour. If tests are successful, the commercial launch of the technology is possible by 2028.
