A sophomore at the University of Maryland, Baltimore County, says he has come up with a way to build a better battery just by bouncing a soccer ball.
Samuel Bendek, who is originally from Colombia, said he got the idea when he was 16 years old and working at a soccer ball manufacturing company. He was bouncing one of the balls with the intention of studying how it returned energy — the kinetic energy of a ball made from natural rubber — and then figured out how to put it in a battery.
Now 21 years old, Bendek is the CEO of a company called Elastic Energy, which takes that rubber tree sap and makes an elastic band into the main fuel source for the battery, which weighs about 200 pounds and is the size of a large suitcase.
“When the battery is charging, we elongate that elastic band up to eight to nine times its original length,” he said. “We elongate with a motor when it’s charging and when you need the energy, we just do the reverse process. The elastic band recovers while moving a generator, converting elastic potential energy into electricity.”
He envisions his batteries working as backup sources of power for buildings like hospitals, data centers and other facilities that can’t afford to be in the dark, but might be looking for a better price.
“The initial price (for other batteries) is very high, and they don’t last too much — six to eight years,” Bendek said, adding that “you have to throw this battery away” after it’s been depleted.
His design will cost less initially, and then save even more in the future.
“What we do is that in five, four years, you just replace the elastic band,” Bendek said. “That is around a little bit less than 20% of the total initial cost. You just replace it and the batteries can work another four years, like if it was new.”
His battery is also less combustible than lithium-ion batteries, and minerals or other elements that leave waste behind don’t need to be extracted. Instead, Bendek said, it’s almost like extracting maple syrup from a tree.
“Tree sap is extracted from the tree without any harm to them,” he said. “Very similar process. You don’t need to cut them, do any harm.”
You just make a rubber band out of it.
Bendek’s company has investors but it isn’t ready to go to market yet.
For now, the goal is to work with a research and development funding program offered by the Department of Energy to further develop the product, and eventually have it ready for mass market in 2027.
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