Korean researchers developed battery lasting five times longer

A Korean research team has developed a new battery manufacturing technology that can extend the battery life of mobile phones by more than five times.

Kim Do-gyeong, a professor of the Materials Science and Engineering Department at the Korea Advanced Institute of Science and Technology (KAIST) and Choi Jang-wook, a professor of the KAIST Graduate School of Energy, Environment, Water and Sustainability, announced Tuesday that they developed a “lithium-sulfur battery” that is more efficient than the existing lithium-ion battery.

This lithium-sulfur battery (weight: 1 kg, output: 387W) developed by the KAIST research team can last for five hours and 24 minutes on a full charge. Given that a lithium-ion battery used in a cell phone can last only one hour in the same weight and output, the research team explains the lithium-sulfur battery’s life is 5.4 times longer than the lithium-ion battery.

In order to enhance the battery efficiency, thin sulfur nano-wires as thick as 75 nm (1 nm = 1/1,000,000,000 m) and as long as 15 μm (1 μm = 1/1,000,000 m) were used as electrodes.

In addition, the problem of battery capacity being lowered by repetitive charging and discharging was solved. Sulfur nano-wires were coated with carbon on surface to prevent sulfur from being melted within a battery, and as a result the battery capacity was maintained at 99.2 percent after 300 times of charging and recharging and over 70 percent after 1,000 times of charging and recharging. If a mobile phone adopts this battery and is charged once a day, the battery capacity will stay at a sustainable level for more than three years. Professor Kim said, “(The technology) will not only extend the battery life of portable electronics, but also be used as a source of power for electric vehicles or pilotless airplanes.”

The research results have been published Tuesday on the front cover of “Advanced Materials,” an international journal on materials science.