Lithi
um-ion battery technology has made it so that portable devices can be used for a good portion of a day before needing more juice. Even then, I find myself wanting more. Maybe it’s because I’ve been spoiled by my iPad’s amazing battery life, but I wish that both my smartphone and my laptop could hold at least half a day’s worth of charge without me having to shut off absolutely every useful function on either electronic.
It looks like my hopes and dreams for my electronics might be fulfilled in the near future.
A team of Stanford researchers have found the solution to make lithium-ion batteries hold ten times the charge they currently can. How? By replacing the battery’s anode, usually constructed out of graphite, with silicon. It sounds like a simple fix, but scientists haven't been able to do so until now because the silicon would be quickly destroyed in a process called decrepitation. Even though silicon atoms would allow more lithium ions to bind than carbon atoms, therefore allowing the battery to store more charge, the silicon would expand and retract as ions flowed through the battery. These expansions and retractions caused cracks in the silicon. Another problem is that the lithium ions would sometimes react with the silicon, removing the battery’s ability to charge.
The Stanford team has developed a technique to strengthen the silicon anodes by making them out of nanowires and hollow nanoparticles. The anode is also coated with an outer layer of silicon oxide, a ceramic material that prevents the silicon from expanding.
For now, these batteries are able to operate for more than 6,000 cycles, well beyond current lithium-ion battery cycle life standards.
The team’s given no timetable for when this technology will be commercialized. For now, they’re working on simplifying the process of creating the new silicon anodes and creating better cathodes to match the new silicon anodes on lithium-ion batteries. I can only hope that such technology will trickle down to the consumer level soon.
