[Courtesy of KIST]
SEOUL -- A joint team of researchers developed a new type of electrodes using carbon fiber paper to increase the durability of high-capacity lithium metal secondary batteries commonly used in electric vehicles. The new paper-type batteries could prevent battery combustions that could trigger catastrophic accidents.
Lithium-ion batteries' anode material plays a crucial role in the operation of the power bank by storing ions from the cathode inside the battery and discharging them to generate electric current. Theoretically, lithium metal anode materials can greatly improve the capacity of batteries by up to 1,000 percent.
However, the lithium-based electrodes can form lithium dendrites, an uneven deposition of lithium crystals, which can damage the separator membrane to cause combustions. It is virtually impossible to put out lithium-ion battery fires and the best way is to wait until all lithium is burnt off.
The Korea Institute of Science and Technology (KIST) said that its researchers formed a joint team with other researchers from the Gwangju Institute of Science and Technology (GIST) and developed the carbon fiber-based paper electrode. The anode consists of thin carbon fiber paper film containing lithium metal. The film was coated with sodium carbonate and amorphous carbon nanoparticles to prevent lithium dendrites from forming.
Through tests, a conventional lithium anode wrapped in a thin copper film was short-circuited after about 100 charge-discharge cycle tests but the new carbon fiber paper anode was stable after more than 300 test cycles. The energy density was increased from the conventional lithium-ion battery's 240 watt-hours per kilogram to 428 watt-hours per kilogram.
"The anode material developed by the joint research team is a great achievement that can accelerate the commercialization of durable and lightweight lithium metal batteries considering that the density of carbon is about five times less than that of copper and its price is also cheaper," KIST researcher Lee Sung-ho said in a statement on February 28.
reporter
Park Sae-jin
swatchsjp@ajunews.com
