Researchers from the University of Colorado Boulder have made a significant breakthrough in understanding battery degradation. This discovery has major implications for enhancing lithium-ion batteries, particularly in electric vehicles (EVs) and renewable energy storage. By identifying the role of hydrogen molecules in the degradation process, the research could lead to more sustainable and long-lasting batteries.
Uncovering Battery Aging
Over time, batteries lose their capacity, a common problem that causes older devices to lose power more quickly. An international research team, led by Michael Toney from the University of Colorado Boulder, has uncovered the molecular mechanisms behind this degradation. Their findings, published in the Science journal, and highlighted in a Science News report, may pave the way for designing more durable batteries.
The Science of Self-Discharge
In lithium-ion batteries, lithium ions move between the anode and cathode to generate electric power. While charging, these ions return to the anode. However, researchers found that hydrogen molecules from the electrolyte interfere with this process, reducing the number of lithium ions that can bind to the cathode. This weakens the electric current, leading to capacity loss over time.
Implications for EVs and Renewable Energy
Lithium-ion batteries are key to the transition from fossil fuels to renewable energy, but they still face challenges like self-discharge and reliance on expensive materials like cobalt. This study sheds light on why current cobalt-free alternatives, such as those using nickel or magnesium, tend to degrade faster. With a better understanding of the causes of self-discharge, engineers can now work on solutions to extend battery life and improve efficiency.
The Future of Battery Technology
As the largest source of US greenhouse gas emissions, the transportation sector is under pressure to adopt EVs. However, the limited driving range and shorter lifespan of EV batteries remain significant hurdles. Toney believes that improving the design of low-cobalt batteries can offer both a larger driving range and longer life, potentially lowering costs and addressing ethical concerns related to cobalt mining.