XL Batteries is using petrochemical infrastructure to store solar and wind power

Summary

Plenty of materials — from sulfur and sodium to manganese and organic molecules — have tried to topple the ubiquitous lithium-ion battery. And, so far, they’ve all failed. Organic batteries, which are built from some of the most abundant chemicals here on Earth, including carbon, oxygen, and nitrogen, has been perhaps the most frustrating failure. They should be cheaper than today’s batteries that use metals. Yet no one has been able to crack the organic battery. Until now, perhaps. A young startup called XL Batteries has a new take on the chemistry, that it says should be cheaper, safer, and more durable than previous organic batteries and, crucially, lithium-ion batteries themselves. “The capital cost should be ultra low,” Tom Sisto, co-founder and CEO of XL Batteries, told TechCrunch. Don’t expect to find the company’s products in a next-generation electric vehicle. The liquid that XL Batteries uses to store electricity is bulkier and heavier than today’s lithium-ion batteries. That’s why the company is targeting grid-scale storage, which cares more about scale, cost, and safety than weight or density. And the scale of XL Batteries’ installations can be, well, extra large. The company exclusively told TechCrunch that it has commissioned a demonstration unit for Stolthaven Terminals, a company that specializes in petrochemical storage. The first unit will be small, relatively speaking, but once it works the kinks out, the company can quickly build larger batteries, Sisto said. Part of the reason Sisto is so optimistic is because a key component of the battery is nothing more than a storage tank. “If we took two of [Stolthaven’s] biggest tanks, it’d be a 700 megawatt-hour battery,” Sisto said. That’s enough to power around 25,000 homes for a entire day. “I believe they have 400 tanks on their site in Houston.” XL Batteries is building what are known as flow batteries. A basic flow battery consists of two tanks connected to pumps that flow two fluids past a membrane...