A battery delivers its energy to an external circuit via its anode electrode.The anode’s material affects its ability to do so. Scientists at Seoul National University have developed more powerful silicon anodes, that could store up to 10 times more energy than graphite.
Is Powerful Silicon An Ideal Battery Anode?
Silicon is the second-most abundant material in earth’s crust, making it a go-to option for battery anodes. But that has only been in theory until now, because silicon swells and cracks each time it charges and discharges.
But the Seoul scientists appear to have altered this shortcoming, using what they call ‘precise nanoscale crystal design’. Here’s what they mean by that:
- They put 32-nano-meter-size lithium fluoride crystals into silicon oxide.
- Then they added a special coating to limit swelling and enable fast charging.
- The compound delivered high energy density, and 1,000+ fast-charge cycles.
- The report that we link to below hints at a 650-mile electric vehicle driving range.
This research matters, because the ability of an electric car to compete, depends on its driving range. And that range, in return, depends on its battery pack. The key factors include the performance of the battery anodes, and how quickly they recharge.
More powerful silicon anodes could help a battery receive a charge faster, and deliver that energy more efficiently. If we can achieve this with silicon anodes, then they could be ten-times more efficient than their graphite counterparts.
What Made This Research More Powerful
This silicon anode research is more powerful than what went on before. Because the Seoul scientists set anode strength to one side, and focused on resistance to repeated volume changes.
In the end, and here’s the key point, they restricted silicon expansion during cycling to 18,9%. This is a remarkable improvement to the 300% expansion of conventional silicon.
Their prototype silicon anode operated stably over more than 1,000 cycles, when between 10 and 80% state of charge. This discovery definitely could bring us closer to high-energy-density, fast-charging batteries.
More Information
What is Silicon Doing in Batteries?
Double Layer Anodes in Silicon Batteries
Preview Image: Roll of Silicon Anode
