Now, 'Smart' lithium-ion battery that warns before it overheats and explodes

Scientists in Stanford University have developed a "smart" lithium-ion battery that gives ample warning before it overheats and bursts into flames.

The battery is designed for conventional lithium-ion batteries now used in billions of cellphones, laptops and other electronic devices, as well as a growing number of cars and airplanes.

Yi Cui, an associate professor of materials science and engineering at Stanford, said that they wanted to create an early-warning system that saves lives and property.

After incidents such as, fire in two aircrafts of the Boeing aircraft company in 2013 and short-circuit in millions of lithium-ion batteries after consumer-laptop the Sony Corporation in 2006, Cui said, they wanted to lower the odds of a battery fire to one in a billion or even to zero.

Manufacturing defects, such as particles of metal and dust, can pierce the separator and trigger shorting, as Sony discovered in 2006. Shorting can also occur if the battery is charged too fast or when the temperature is too low - a phenomenon known as overcharge.

To address the problem, Cui and his colleagues applied a nanolayer of copper onto one side of a polymer separator, creating a novel third electrode halfway between the anode and the cathode.

The copper layer acted like a sensor that allows you to measure the voltage difference between the anode and the separator. When the dendrites grow long enough to reach the copper coating, the voltage drops to zero. That lets you know that the dendrites have grown halfway across the battery. It's a warning that the battery should be removed before the dendrites reach the cathode and cause a short circuit.

You might get a message on your phone telling you that the voltage has dropped to zero, and the battery needs to be replaced and the early-warning technology can also be used in zinc, aluminum and other metal batteries. "It will work in any battery that would require you to detect a short before it explodes.

Study was published in the journal Nature Communications.