Smartphone and laptop batteries could soon see a ten-fold increase in both the charging speed as well as battery life. Researchers at Northwestern University have developed a lithium-ion electrode that enables conventional lithium-ion batteries to get ten times more capacity and would still run five times as efficient as current batteries after 150 charging cycles or about a year of use.
The boost comes from an adjustment in the charging materials used. Traditional lithium-ion batteries charge by moving electrons from the electrolyte into the anode, which is usually made of graphene. An alternative and more efficient material is silicon, which allows four lithium atoms per one silicon atom while the graphene allows only one lithium atom per six carbon atoms.
Although superior, silicon has a tendency to expand and contract during charging, causing damage to the battery. Hence, to address this, the Northwestern University research team sandwiched clusters of silicon with graphene sheets, which would avoid battery fragmentation.
The researchers also drilled tiny holes of 10- to 20-nm in the sheets to speed up recharging time. The next step for the team is to improve the cathode and electrolyte so that the battery can automatically shut off to prevent fires or explosions should the battery temperature get too high.