Bottling the Sun: UCSB Scientists Create Rechargeable Solar Battery

Imagine a world where you can harness the power of the sun and store it for later use, without the need for bulky batteries or electrical grids.

TL;DR
• UCSB scientists have developed a new material that captures sunlight and stores it within chemical bonds.
• The material, called pyrimidone, can release the stored energy as heat on demand.
• This breakthrough could revolutionize off-grid heating and more.

Summary
Scientists at UC Santa Barbara have developed a new material that captures sunlight, stores it within chemical bonds, and releases it as heat on demand. This bio-inspired molecule, called pyrimidone, is a modified organic molecule that outperforms lithium-ion batteries. It has an energy density of more than 1.6 megajoules per kilogram, roughly double that of a standard lithium-ion battery.

The molecule works by twisting into a strained, high-energy shape when hit with sunlight, staying locked in that shape until a trigger releases the stored energy as heat. The team demonstrated that the heat released from the material was intense enough to boil water, a significant achievement in the field. This capability opens the door for practical applications ranging from off-grid heating to residential water heating.

The research team, led by Associate Professor Grace Han, drew inspiration from DNA and designed a synthetic version of a component found in DNA that can undergo reversible structural changes. The team's new molecule is a heavy hitter, with a compact and lightweight design that prioritizes energy storage and release. Key benefits of this technology include:
• High energy density
• Reusable and recyclable material
• Potential for practical applications in off-grid heating and residential water heating
• Ability to boil water under ambient conditions

The research was supported by the Moore Inventor Fellowship, which Han received in 2025 to pursue the development of these 'rechargeable sun batteries.' The team's breakthrough was translating high energy density into a tangible result, demonstrating the material's potential for real-world applications.

As we continue to explore new ways to harness the power of the sun, we must also consider the potential impact on our environment and our daily lives.