The Weird Batteries That Could Store Renewable Energy

The world of energy storage has long been dominated by lithium-ion batteries. However, a new generation of innovators is pushing the boundaries of what’s possible with unconventional materials and technologies. Researchers and engineers in various parts of the globe are experimenting with novel approaches to harness renewable energy and store it for later use.

One such innovation is the “liquid air” cryobattery developed by Highview Power in Manchester. This system captures surplus renewables during the day and stores them as liquid air at -196C. When needed, the liquid air expands through a turbine to generate electricity without emissions. The implications are significant: this technology could store energy for hours, days, or even weeks.

In Nevada’s desert, the Crescent Dunes scheme has been harnessing solar power to heat a reservoir of potassium and sodium nitrate to 560C. This molten salt can be maintained for 10 hours after sunset, providing a clean source of energy that can be converted into electricity when needed. The use of molten salt storage is not new; it’s being used in guided missiles and nuclear weapons to provide a reserve battery.

A notable example of large-scale molten salt battery technology is Denmark’s 1GWh project, which stores clean electricity for up to two weeks by heating the salts to approximately 600C. In southern Finland, sand batteries are being used to store energy in the form of heat. The small town of Pornainen has invested in a massive sand battery that can cover almost a month’s heat demand during the summer months and close to a week during winter.

In Japan, researchers at Tokyo University have developed wearable patches that generate electricity directly from human sweat. This technology solves the problem of powering sensors in wearable devices without bulky batteries. The increasing urgency to decarbonize economies and reduce emissions is driving companies and researchers to think outside traditional battery technologies.

Traditional lithium-ion batteries are expensive and rely on critical minerals like lithium, cobalt, and nickel that have raised concerns for environmental protection and vulnerable communities. As the world transitions towards a low-carbon economy, we can expect more experiments with unconventional materials and technologies. The implications are far-reaching: from powering homes to industries, and even wearable devices, the possibilities are endless.

However, scaling up these new technologies will require significant investment and infrastructure development. Moreover, their environmental impact needs to be carefully assessed to ensure they don’t create new problems in the process of solving old ones. As the energy landscape continues to evolve, one thing is clear: innovators who are redefining power storage today will shape the course of our collective future tomorrow.