The original link about this news brief.
29 August 2014 — Lithium ion batteries are an essential component of technologies like electric cars and could help to store energy from renewable, yet intermittent sources of energy like wind. But cycles of charging and discharging lead to failures, limiting their useful life.
“As batteries charge and discharge, a fascinating interplay of mechanics and chemistry occurs at the nanoscale,” graduate student Andrew Ulvestad said.
Lithium ions strain the material as they shuttle between electrodes and can even alter its structure, which lead to defects. Designs for more resilient electrodes will rely on fundamental understanding of the interactions between lithium ions and electrodes within the structure of a battery, but that has proved elusive until now.
Using a novel technique called coherent X-ray diffractive imaging, Ulvestad, Andrej Singer and colleagues mapped the three-dimensional strain in nanoparticles in within the electrodes of operating coin cell batteries, like those found in watches. In two papers recently published in Nano Letters, they report evidence that the history of charge cycles alters the patterns of strain in single particles of the electrode material.
This new approach will help to reveal fundamental processes underlying the transfer of electrical charge, insight that could help to guide the design of economical batteries with longer useful lives.
Hyung-Man Cho and Jong Woo Kim, graduate students in materials science and engineering, Jörg Maser and Ross Harder of Argonne National Laboratory and Jesse Clark of SLAC National Accelerator Laboratory contributed to this work, which was directd by Shirley Meng, professor of nanoengineering and Oleg Shpyrko professor of physics. The U.S. Department of Energy and a UC San Diego Chancellor’s Interdisciplinary Collaboratories Award provided financial support. —Susan Brown