Designing a Safer Battery for Smartphones (That Won’t Catch Fire) (Published 2016)

SAN FRANCISCO — Mike Zimmerman likes to shock his guests by using a hammer to drive a nail through a solid polymer lithium metal battery. Nothing happens — and that’s a good thing. Mr. Zimmerman’s battery is a new spin on lithium-ion batteries, which are widely used in products from smartphones to cars. Today’s lithium-ion batteries, as anyone who has followed Samsung’s recent problems with flamma