Why Your Batteries Keep Dying: The Shocking Truth Revealed!
Batteries Lose Power Answer
Why Do Batteries Lose Power? Scientists Find the Answer
Researchers have unveiled a key mechanism behind battery degradation that could transform the future of lithium-ion battery design, potentially extending the driving range and lifespan of electric vehicles (EVs) and advancing sustainable energy storage technologies. The study highlights the role of hydrogen molecules in interfering with lithium ions, providing critical insights that may pave the way for more sustainable and economically viable battery solutions.
Batteries Lose Power Answer: Deciphering the Aging Process in Batteries
Over time, batteries lose their ability to hold a charge, which explains why older smartphones deplete faster. Yet, this widely observed phenomenon remains only partially understood.
An international consortium of researchers, spearheaded by an engineer from the University of Colorado Boulder, has now uncovered the underlying mechanism driving this degradation. This breakthrough holds the promise of enabling scientists to create superior batteries, thereby allowing EVs to travel further and last longer, and propelling energy storage innovations that could speed up the shift towards clean energy.
These findings were published today (September 12) in the journal Science.
Repercussions for Renewable Energy and Electric Vehicles
“We are advancing lithium-ion battery technology by understanding the molecular processes that lead to their degradation,” explained Michael Toney, the study’s lead author and a professor in the Department of Chemical and Biological Engineering. “Improving battery performance is crucial for transitioning our energy systems from fossil fuels to more sustainable alternatives.”
Engineers have long been developing lithium-ion batteries—the predominant type of rechargeable battery—without using cobalt, a costly and rare mineral tied to severe environmental and human rights abuses. In the Democratic Republic of Congo, which provides over half of the world’s cobalt, many miners are children.
Researchers have attempted to replace cobalt with elements such as nickel and magnesium. However, these alternatives have resulted in even higher rates of self-discharge, a process in which internal chemical reactions deplete stored energy and degrade battery capacity over time. Due to self-discharge, most EV batteries currently have a lifespan of about seven to ten years before requiring replacement.
Probing the Causes of Self-Discharge in Batteries
Toney, also a fellow at the Renewable and Sustainable Energy Institute, and his team set out to investigate self-discharge. In a standard lithium-ion battery, lithium ions—carrying electrical charges—move from the anode to the cathode through an electrolyte medium, generating an electric current that powers devices. Charging reverses this flow, returning ions to the anode.
Previously, scientists suspected that self-discharge occurred because not all lithium ions returned to the anode during charging, diminishing the available charged ions needed to generate current.
Utilizing the Advanced Photon Source, a powerful X-ray instrument at the U.S. Department of Energy’s Argonne National Laboratory in Illinois, the researchers discovered that hydrogen molecules from the electrolyte migrate to the cathode, occupying sites where lithium ions would typically bind. Consequently, fewer binding sites for lithium ions on the cathode lead to a weaker electric current and reduced battery capacity.
Batteries Lose Power Answer: Future Directions for Electric Vehicle Batteries
Transportation remains the largest source of greenhouse gas emissions in the U.S., contributing 28% of the nation’s total emissions in 2021. To curb these emissions, many automakers have pledged to phase out gasoline vehicles in favor of EVs. However, EV manufacturers face significant hurdles, including limited driving ranges, high production costs, and shorter battery lifespans compared to conventional cars. Currently, a standard all-electric vehicle in the U.S. market can travel approximately 250 miles on a single charge, roughly 60% of a gasoline car’s range. According to Toney, this new research could help address these issues.
“All consumers desire cars with longer ranges. Some of these low-cobalt batteries could potentially offer greater range, but we also need to ensure they remain durable over time,” Toney noted, emphasizing that reducing cobalt could lower costs and address human rights and energy justice concerns.
Approaches to Prolonging Battery Life
Armed with a deeper understanding of self-discharge mechanisms, engineers can now explore strategies to mitigate this process, such as coating the cathode with special materials to block hydrogen molecules or using alternative electrolytes.
“With this knowledge of what causes battery degradation, we can guide the battery chemistry community on necessary improvements in battery design,” Toney said.
Reference
“Solvent-mediated oxide hydrogenation in layered cathodes,” Science, September 12, 2024. DOI: 10.1126/science.adg4687.
