Safer Batteries

Ever since we heard about the first exploding phone, another major focus of battery research has been safety. Lithium-ion batteries are constructed from toxic and flammable materials, meaning that even small defects can result in safety hazards from overheating. But another team of researchers recently developed a battery that’s virtually indestructible. Not only can it be cut, shot, bent and soaked without interrupting power, it’s also fireproof.

In traditional lithium-ion batteries, overheating is basically due to the electrolyte, which can break down over time and create a short circuit. When the heat from such a reaction comes into contact with an oxygen-rich cathode, the result is a flaming battery. Their solution is a water-based electrolyte that’s mixed with a polymer to create a soft plastic. This allowed them to increase the electric potential from about 1.2 volts (typical of current aqueous batteries) to 4 volts, which is comparable with current lithium-ion batteries.

The soft-flexible battery opens up a host of new uses such as integrating it into fabric to create wearable electronics. It’s also usable for underwater applications. The next step will be to finetune the electrolyte chemistry to improve the battery life, which is currently only about 100 charge cycles.