A material under development at Karlsruhe Institute of Technology (KIT) in Germany could reduce the cost and add to the environment sustainability of sodium-ion batteries. The batteries are preferred in some instances to their nickel-metal hydride or lead acid counterparts due to the greater abundance and accessibility of assembly materials.

Carbon materials for batteries are derived from apple waste. Source: KIT/HIU For the KIT battery negative electrode, carbon-based active materials are synthesized from apple biowaste. The hard carbon demonstrates good electrochemical performance, with excellent long-term cycling stability and high specific capacity documented over 1,000 charge/discharge cycles, researchers say.

The positive electrode is composed of layers of sodium oxide, which can be produced without the cobalt frequently used in active materials of commercial lithium-ion batteries. Capacity, voltage and stability properties were comparable to those of a cobalt-containing battery.

The research may be an important step toward the sustainable use and exploitation of organic waste.