KRICT adds graphitic carbon nitride to lithium-ion cathodes, lifting power delivery in early tests

The Korea Times reported the work, which was described by TechRadar. In a lithium-ion cell, charging drives lithium ions out of the cathode, through an electrolyte, to the anode; discharging sends the ions back in the other direction.

One route to storing more energy in a battery of the same size and weight is to make the cathode thicker, but doing so also makes it harder for lithium ions to move through the electrode and deliver all the energy the cell holds. The KRICT team's additive is aimed at that trade-off.

The researchers reported that adding graphitic carbon nitride to the cathode produced a 166% increase in capacity during high-rate discharge, with power density rising by up to 2.85 times. The figures do not represent a larger capacity in milliamp-hour terms, but more of the stored charge delivered under heavy load and for longer. In lithium-ion cells, drawing energy quickly reduces the total capacity obtained compared with drawing the same amount of energy slowly.

In an electric vehicle, that would mean harder acceleration sustained for longer without eroding total range as much. A home battery paired with appliances that drain power quickly, such as washing machines, would hold up better. Drones, which pull large bursts of power to lift off, and gaming or workstation laptops, whose draw varies with workload, fall into the same category.

The researchers say the approach could in turn allow thicker cathodes that do yield more milliamp-hour capacity in the same space, but that was not tested in this study. The next challenge is to scale up and expand the technology, which remains at an early stage.

Shin Seok-min, president of KRICT, said the alternative approach to lithium-ion batteries could potentially be used across electric vehicles, energy storage systems and robotics, making it broadly applicable, particularly to devices and systems that can accommodate physically larger batteries.