An international team of researchers has revealed an unexpected factor that speeds up the deterioration of lithium-ion batteries, leading to a consistent decrease in charge. This finding enhances our understanding of battery longevity and presents methods to address self-discharge, potentially boosting performance in devices ranging from smartphones to electric vehicles.
An international team of scientists has identified a surprising factor that accelerates the degradation of lithium-ion batteries leading to a steady loss of charge. This discovery provides a new understanding of battery life and offers strategies to combat self-discharge, which could improve performance in various applications from smartphones to electric vehicles.
Artūras Vailionis, a key leader within the X-ray and Surface Analysis group at Stanford University and a visiting professor at the Kaunas University of Technology (KTU) in Lithuania, notes that it has been widely accepted that the self-discharge of a fully charged battery arises from the movement of lithium atoms from the electrolyte to the battery’s cathode.
“However, our research indicates that the self-discharge in batteries is actually caused by the movement of protons (hydrogen ions). The findings from this study suggest potential methods to enhance battery longevity by reducing self-discharge,” Vailionis explains.
Such methods may involve adding additives to the electrolyte that do not contain hydrogen molecules, like CH2, or applying a specialized coating to the cathode’s surface to minimize its interaction with the electrolyte.
Extending battery life for a more sustainable and economical technology
According to Prof. Vailionis, self-discharge diminishes both the calendar and cyclic lifespan of batteries, ultimately leading to a reduction in voltage and capacity. The limited lifespan of lithium batteries has significant environmental and economic implications; hence, it is crucial to comprehend and mitigate this problem.
The revelation of a completely new factor contributing to battery self-discharge could lead to more sustainable, affordable, and dependable technologies.
“When lithium-ion batteries last longer, it means that consumers don’t have to replace their batteries or electronic devices as frequently. Additionally, longer battery life aids in decreasing electronic waste and curbing resource depletion since lithium, cobalt, and nickel are finite resources. This contributes to more sustainable practices,” states Vailionis, a visiting professor at KTU, Lithuania.
Devices with extended battery life, such as smartphones and laptops, can be used longer without needing a recharge. Moreover, in industrial settings with vast battery systems like electric vehicles or energy storage grids, longer battery longevity leads to higher returns on investment, making these technologies more cost-effective. Longer battery life in renewable energy systems, such as solar and wind power, boosts efficiency and reliability in energy storage while stabilizing supply and reducing reliance on fossil fuels.
In sectors such as medical devices, aerospace, and defense, longer battery longevity minimizes the risk of failures during critical situations.
“In essence, extended battery life enhances sustainability, economics, and productivity across various industrial applications,” Vailionis adds.
The result of collaboration among a vast international team of scientists
Prof. Vailionis underscores that the findings stem from the efforts of a large international team of scientists across different fields. His team at Stanford University utilized X-ray diffraction to uncover two distinct structures within the cathode: one on the surface (influenced by hydrogen ions) and one occurring deeper inside. X-ray reflectometry also confirmed the presence of a surface layer containing hydrogen atoms.
Vailionis has served as a visiting professor at KTU, Lithuania for 13 years, where he teaches a course on X-ray diffraction to physics students annually and collaborates on joint projects with KTU scientists.
“Since my departure, Lithuania has transformed remarkably: universities are now receiving significantly better funding for education and have access to European grants. Scientists and PhD students enjoy excellent opportunities to travel to other universities and research institutions for study and to present their findings at conferences,” shares the KTU visiting professor.
He observes that Lithuanian students have also transformed: “They are far more engaged in class compared to when I was a student, and they encounter no issues with the English language.”
