Date: Feb 08, 2016 Author: Adrian Potoroaca Source: IEEE Spectrum (
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While improvements in silicon have made hardware more energy-efficient than ever, battery technology has lagged behind, despite numerous efforts to make them store more charge as well as charge faster, not to mention safer and more durable.
Researchers at Cornell University believe they have found a solution to a problem that has been a huge bump in the road for lithium metal batteries. Using lithium in the anode has been shown to result in a tenfold increase in capacity per gram when compared to typical lithium ion batteries (up to 3860 mAh/g vs 380 mAh/g), a big improvement no matter how you look at it.
The problem with lithium metal batteries is that the lithium in the anode is so reactive that, when you recharge the battery, it will form dendrites (or tree-like bumps) that eventually extend through the electrolyte all the way to the cathode, effectively causing a short-circuit which can lead to thermal runaway and some pretty scary safety hazards.
While other researchers have tried using a ceramic membrane as a barrier for lithium dendrite growth, this degrades the performance and requires high temperatures (300-400 degrees Celsius) to work reliably, and that is not exactly suitable for use in your next iPhone.
Chemical and biomolecular engineering professor Lynden Archer's team has created a new membrane "by grafting polyethylene oxide onto silica to form nanoscale organic hybrid materials" - "hairy" nanoparticles that can effectively stop dendrite growth at room temperature.
The researchers claim that this solution does not require a radical redesign in battery technology, and can be "as effective as batteries based on other metals, such as sodium and aluminum, that are more earth-abundant and less expensive than lithium and also limited by dendrites."
If you want a more in-depth reading, you can check the original paper published on Nature Communications.
Source: Cornell via IEEE Spectrum | Images via Cornell University
