In a major development for the electric vehicle (EV) industry, scientists have made a significant discovery that could prevent a harmful and potentially hazardous occurrence during fast charging: lithium plating.
This phenomenon occurs when lithium ions accumulate on the surface of the battery's negative electrode, known as the anode, instead of effectively integrating themselves into it through a process called intercalation.
Consequently, these ions form a layer of metallic lithium that continues to grow on top of the anode. This can result in detrimental effects such as battery damage, reduced lifespan, diminished overall performance, and even the possibility of short-circuits leading to fires or explosions.
Led by Dr. Xuekun Lu from Queen Mary University of London, a team of researchers has discovered that the key to suppressing lithium plating in a graphite anode lies in optimizing its microstructure. This is achieved by carefully adjusting the particle and electrode morphology to ensure a uniform reaction activity and a decreased local lithium saturation.
This breakthrough holds immense promise for the EV industry, as it could pave the way for safer and more efficient fast charging technologies. With the ability to prevent lithium plating, electric vehicle batteries could enjoy improved longevity, enhanced performance, and reduced risks of safety incidents.
“Our research has revealed that the lithiation mechanisms of graphite particles vary under distinct conditions, depending on their surface morphology, size, shape, and orientation. It largely affects the lithium distribution and the propensity of lithium plating” said Dr Lu.
“Assisted by a pioneering 3D battery model, we can capture when and where lithium plating initiates and how fast it grows.”
The full paper can be found in the journal Nature.
The study provides valuable insights into how lithium is redistributed within graphite particles during fast charging, which could potentially lead to the development of more efficient fast charging protocols. Another important finding is that improving the microstructure of the anode can increase the battery's energy density, allowing for longer distances to be covered on a single charge.
Dr. Lu stated that this is a significant breakthrough with the potential to greatly impact the future of electric vehicles. Faster-charging and longer-lasting batteries are crucial for enabling a complete transition to electric mobility.
Overall, the study offers valuable insights into the physical processes of lithium redistribution within the graphite particles during fast charging. Notably, these learnings could enable the development of advanced and more efficient fast charging protocols.
Another finding is equally important: refining the microstructure of the anode can boost the battery’s energy density — meaning, longer distances on a single charge.
“This is a significant breakthrough that could have a major impact on the future of electric vehicles,” Dr Lu noted. And, indeed, faster-charging and longer-lasting EV batteries are critical in enabling our full transition into electric mobility.