It can sometimes feel a little depressing wandering the halls of the world's biggest tech show and find so little designed to tackle our planet's biggest problems. Every time I attend CES, I keep my eyes peeled for technology that has the potential to make its mark on society in a more profound way, and at this year's show, I discovered a humdinger. (Here are some more of the most eye-popping finds.)Read more: The Official Best of CES 2025 Winners, Awarded by CNET GroupSingaporean startup Flint makes rechargeable paper batteries, which CNET chose as the winner of the Best of CES Sustainability award on Thursday. They're fully flexible and can be shrunk down to the size of a coin battery or embedded in a smartwatch strap.Flint's paper batteries share a structure with traditional lithium-ion batteries, but that's where the similarities end. Their key component is cellulose, which acts as a natural medium for ion transfer between the anode and cathode, a critical chemical exchange necessary for batteries to work. CES 2025: We're Obsessed With These 28 New Products So Far See all photos The mining and production of lithium-ion batteries are responsible for significant CO2 emissions, leaking toxic chemicals and depleting waterways, all of which contribute to the wider climate crisis. With our battery requirements growing rather than diminishing, solutions like Flint's are key to reducing the environmental impact of our tech obsession."Our supply chain is very abundant, and we don't require rare earth or toxic material and scarce materials," said Flint Co-Founder Carlo Charles. Some of them, like zinc and manganese, can even be found in your food and body, he added.Disposing of traditional batteries also puts a huge strain on the environment, but paper batteries can biodegrade within six weeks. Charles tells me that in the team office in Singapore, they compost their used batteries to nourish the office plants. Flint's batteries biodegrade and can be used to further feed plants feed plants. Katie Collins/CNETRight now, the company is focused on making smaller batteries for smaller consumer electronics, but there's no reason why one day these can't scale up. "We want to go even further and see how we can embed our products in your smartphones," said Charles. "Folding smartphones could have folding batteries in them there's so much potential."Much further down the line, the paper battery could be scaled to fit into the door of an electric door or wing of an electric plane. As the batteries are so thin, they can be layered, and they also don't pose the same fire hazard as their lithium-ion predecessors.In the week before CES, Flint secured $2M of funding that the company plans to use to build a pilot production facility in Singapore. Establishing the pilot in a country with none of the cobalt, lithium or other minerals traditionally used to make batteries will help prove that the battery industry can be decentralized, says Charles. CES Proves It's Still Deeply Weird With These Bonkers Gadgets See all photos The company already has plans to return to CES next year with an even bigger presence -- although this year's booth was an impressive feat of sustainable engineering in and of itself. The entire thing was constructed from cardboard that could be packed down into a single box.It's with all of this that Flint has planted a flag at CES 2025. We're excited to see where the company's paper batteries go next.