Researchers upcycle plastic bags into battery parts

Researchers have reported a new method to convert plastic bags into carbon chips that could be used as anodes for lithium-ion batteries.

Scientists have long recognised that plastic bags could be an inexpensive source of energy-storing carbon, but previous methods to upcycle polyethylene into pure carbon have been inefficient or required expensive, complex processes.

Vilas Pol and colleagues wanted to develop a simpler yet efficient approach to convert plastic waste into useful carbon-containing materials.

 The researchers immersed polyethylene plastic bags in a sulfuric acid and sealed them inside a solvothermal reactor, which heated the sample to just below polyethylene’s melting temperature.

This treatment caused sulfonic acid groups to be added to the polyethylene carbon-carbon backbone so that the plastic could be heated to a much higher temperature without vaporising into hazardous gases.

They then removed the sulfonated polyethylene from the reactor and heated it in a furnace in an inert atmosphere to produce pure carbon.

The team ground the carbon into a black powder and used it to make anodes for lithium-ion batteries, which performed comparably to commercial batteries.