See the way those smooth, amorphous blobs rapidly transform into textured honeycombs? Something similar is probably happening right now inside your laptop or smartphone’s battery, providing you with portable power.
But the cherished efficiency and portability of those compact lithium-ion batteries comes with a cost: each cycle of discharge/recharge degrades the material’s essential structure and ultimate longevity – you’ve probably noticed that your older electronics just don’t hold a charge like they used to. Preventing this persistent degradation requires insight into a process that plays out on the elusive scale of just billionths of a meter.
Fortunately, Brookhaven scientists just demonstrated a breakthrough transmission electron microscopy technique that captures live action lithium-ion reactions with nanoscale precision.
“We’ve opened a fundamentally new window into this popular technology,” said physicist and lead author Feng Wang. “The live, nanoscale imaging may help pave the way for developing longer-lasting, higher-capacity lithium-ion batteries. That means better consumer electronics, and the potential for large-scale, emission-free energy storage.”
These real-time experimental observations, including the movie above, revealed that the lithium ions swept rapidly across the surface of iron fluoride nanoparticles in a matter of seconds. The transformation then moved slowly through the bulk in a layer-by-layer process that split the compounds into distinct regions (similar to spinodal decomposition).
Imagine watching a fire spread across the surface of a log and then steadily eating its way through the layers of wood—only rather than smoke, the lithium ion reaction forms trails of new molecules. Just as burnt wood reveals fundamental characteristics of fire, the changes in morphology and structure in these individual nanoparticles provided crucial information about the lithium reaction mechanisms.
Get the full story at the official press release.