Prototype batteries could make consumer electronics last twice as long

Original press release was issued by MIT, written by Rob Matheson
We all know the drill. you charge up your smartphone overnight, make a couple of phone calls during the day, play a generic game for a few minutes on a lunch break, and surprise, surprise, by the time you make it back to bed, the batteries are prone to be charged again. Life expectancy of batteries is just as frustrating as it is tricky to prolong. However, SolidEnergy Systems, winner at the MIT $100K Entrepreneurship Competition’s Accelerator Contest, founded by Qichao Hu ’07, MIT alumnus and former postdoc, managed to develop a prototype lithium metal battery, that is twice as energy-dense, yet just as safe and long-lasting as the lithium ion batteries that power many of today’s consumer electronics, drones and electric cars among them.

“With two-times the energy density, we can make a battery half the size, but that still lasts the same amount of time, as a lithium ion battery. Or we can make a battery the same size as a lithium ion battery, but now it will last twice as long,” says Hu.

Researchers sought to make batteries like that for decades. “It is kind of the holy grail for batteries,” says Hu. Their prototype essentially swaps out a common battery anode material, graphite, for very thin, high-energy lithium-metal foil, which can hold more ions — and, therefore, provide more energy capacity.  Due to chemical modifications, the lithium metal batteries are also made rechargeable and safer to use. SolidEnergy plans to bring the batteries to smartphones and wearables in early 2017, and to electric cars in 2018. But the first application will be drones, coming this November.

The road to creating the prototype was a bumpy one. Hu’s team needed to address some major issues such as shrinking the battery in size and also making it work at room temperature. They developed an innovative ultrathin lithium metal foil for the anode, which is about one-fifth the thickness of a traditional lithium metal anode. That shrunk the battery in half. Furthermore, the battery only worked at 80 degrees Celsius or higher. To tackle this issue, Hu developed a solid and liquid hybrid electrolyte solution. He coated the lithium metal foil with a thin solid electrolyte that doesn’t need to be heated to function.

“Industry standard is that electric vehicles need to go at least 200 miles on a single charge. We can make the battery half the size and half the weight, and it will travel the same distance, or we can make it the same size and same weight, and now it will go 400 miles on a single charge.” proposes Hu.

Back in 2012, the landscape didn’t look good for battery companies. A123 Systems, The well-known MIT spinout developing advanced lithium ion batteries filed for bankruptcy. However, SolidEnergy was blessed with the opportunity to use the A123’s then-idle facilities — which included dry and clean rooms, and manufacturing equipment — to create the prototype. When A123 was acquired by Wanxiang Group in 2013, SolidEnergy signed a collaboration agreement to continue using A123’s resources. After three years of sharing A123’s space, SolidEnergy moved its headquarters to a brand new facility this month, with aims of ramping up production for their November launch.