A flexible battery made from hydrogel can withstand being run over by a car, blows from a hammer and temperatures as low as −77°C (-106.6°F). It could potentially be used in phones or wearable electronics.
Most commercial batteries are solid and based on lithium, but these can be easily damaged in accidents and cope badly at very cold temperatures.
Now, Ximin He at the University of California, Los Angeles, and her colleagues have developed a hydrogel …