Engineers in Australia have created a new type of water-based battery that could make it easier and cheaper for households to store energy from rooftop solar panels.
This next-generation “flow battery” uses safe, non-toxic materials and may cost far less than the $10,000 lithium-ion battery systems currently used in many homes.
Flow batteries are not new—they’ve been used for decades to store energy at a large scale. However, they’ve typically been too bulky and slow to charge for household use.
That’s now changing thanks to new research from Monash University, where scientists have redesigned the core part of the battery—a special membrane—to allow much faster charging.
Wanqiao Liang, the lead author of the study and a Ph.D. candidate in materials science, said their membrane design is a game-changer.
“We’ve taken a safe, affordable chemistry and made it fast enough to keep up with rooftop solar in real time,” she explained.
This new design lets the battery charge quickly, perform better, and last longer—all while staying affordable and safe for home use.
What makes Monash’s version special is the balance it strikes between speed, safety, and cost. Liang said the key was improving ion selectivity—the ability to let the useful materials move through the battery while blocking the ones that cause damage.
Their new membrane outperformed the industry-standard Nafion, staying stable and fast even after 600 charge cycles.
The battery stores energy in liquid rather than solid materials, which helps bring the cost down and makes it safer. Unlike lithium-ion batteries, which can catch fire or overheat, these flow batteries are non-flammable and non-toxic.
They’re made from widely available materials, making them more environmentally friendly and easier to produce at scale.
“This is the kind of battery you’d want in your garage,” Liang said. “It’s safe, affordable, and can keep up with the energy your solar panels produce on a sunny day.”
The research team is now 3D printing battery prototypes and testing them in real-world conditions.
If all goes well, these home-friendly water batteries could be available on the market within a few years, offering a promising new way for households to store clean energy.
