UCSB scientists develop ‘liquid battery’ that stores sunlight as heat
Scientists at U.C. Santa Barbara have developed a new kind of “liquid battery” that can capture sunlight and release it later as heat, a breakthrough researchers say could help solve one of renewable energy’s biggest challenges — storing solar energy after the sun goes down.
The discovery, published this week in the journal Science, comes from a research team led by UCSB chemist Grace Han, whose group engineered a bio-inspired molecule capable of storing solar energy inside chemical bonds rather than traditional electrical batteries.
Solar panels stop generating power at night, forcing most renewable energy systems to rely on lithium-ion batteries that can be expensive, bulky and degrade over time. The UCSB material instead stores energy chemically, functioning more like a rechargeable fuel that can hold sunlight for later use.
“We typically describe it as a rechargeable solar battery,” said Han Group doctoral researcher Han Nguyen, the study’s lead author. “It stores sunlight, and it can be recharged.”
To create this molecule, UCSB’s media release stated, the team looked to a surprising source: DNA. “The pyrimidone structure is similar to a component found in DNA that, when exposed to UV light, can undergo reversible structural changes.”
Researchers collaborated with UCLA chemist Ken Houk to model why the molecule remains stable while holding energy for long periods without significant loss.
Researchers say the material can store about twice as much energy as a typical lithium-ion battery. In testing, it even generated enough heat to boil water — a sign the technology could eventually work in real-world settings.
“Boiling water is an energy-intensive process,” Nguyen said. “The fact that we can do that is a big achievement.”
Because the material dissolves in water, researchers say future systems could circulate the liquid through rooftop solar collectors during the day and store it in tanks, releasing heat at night for uses such as residential water heating, off-grid energy systems or backup heating during outages.
“With solar panels, you need an additional battery system to store the energy,” said co-author Benjamin Baker. “With molecular solar thermal energy storage, the material itself stores that energy.”
California leads the nation in rooftop solar adoption, according to the school, but long-term energy storage remains one of the biggest barriers to expanding renewable power. Technologies that store sunlight without large battery systems could reduce costs and improve reliability during periods when electricity demand remains high after sunset.
Scientists say the technology remains experimental but represents a significant step toward long-duration solar energy storage.
Copyright 2026 Nexstar Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
For the latest news, weather, sports, and streaming video, head to KTLA.