The last thing any electric car owner wants want is to have to constantly be recharging it, especially since many places don't have a lot of charging stations. The range of electric car batteries is getting longer every year, and a new development could majorly increase how far you can drive on a charge.
Researchers at the Center for Energy Storage Research of the Korea Institute of Science and Technology (KIST) announced on Friday that they've developed silicon anode materials that could double the range of an electric vehicle. Their research was published in the journal Nano.
An anode is a positively charged electrode found in electric vehicle batteries, phone batteries and more. Today's electric cars have graphite anodes, which work well enough, but researchers have been working on perfecting silicon anodes for years because they can hold about 10 times more electrons than graphite anodes. The problem has been that these silicon anodes absorb too many lithium ions and expand to the point of cracking, while graphite doesn't have this issue. This new research apparently shows how we can overcome that problem.
The researchers were able to create carbon-silicon composites by dissolving starch in water and silicon in oil and then mixing them at a relatively high temperature. This composite they were able to create can hold four times as many electrons as graphite and doesn't expand to the point of cracking as they were trying to avoid. They claim it can allow a battery to charge to 80 percent capacity within only five minutes. Imagine charging your car, your laptop or your phone that quickly.
Dr. Jung, the lead researcher of the KIST team, said in a statement that this simple process produced amazing results.
"We were able to develop carbon-silicon composite materials using common, everyday materials and simple mixing and thermal processes with no reactors," Jung said. "The simple processes we adopted and the composites with excellent properties that we developed are highly likely to be commercialized and mass-produced. The composites could be applied to lithium-ion batteries for electric vehicles and energy storage systems (ESSs)."
A lot of other researchers and companies are working on their own processes for perfecting the silicon anode. Sila Nanotechnologies, which has partnered with BMW and Daimler, has been raising a ton of money thanks to its development of a working silicon anode. Its anode has silicon within a porous scaffolding that allows it to expand and contract without breaking the anode. Sila's anode has a 20 percent higher energy density than a graphite anode.
Everyone is racing to make silicon work so batteries can be greatly improved, and it's not clear which technique will end up being the industry favorite, but what is clear is that we're soon going to have batteries for our cars, phones and more that hold more of a charge, charge faster and generally make our lives easier. I think it's safe to say we'll all be happy with spending less of our lives charging devices.
Abstract: Silicon has a great potential as an alternative to graphite which is currently used commercially as an anode material in lithium-ion batteries (LIBs) because of its exceptional capacity and reasonable working potential. Herein, a low-cost and scalable approach is proposed for the production of high-performance silicon–carbon (Si–C) hybrid composite anodes for high-energy LIBs. The Si–C composite material is synthesized using a scalable microemulsion method by selecting silicon nanoparticles, using low-cost corn starch as a biomass precursor and finally conducting heat treatment under C3H6 gas. This produces a unique nano/microstructured Si–C hybrid composite comprised of silicon nanoparticles embedded in micron-sized amorphous carbon balls derived from corn starch that is capsuled by thin graphitic carbon layer. Such a dual carbon matrix tightly surrounds the silicon nanoparticles that provides high electronic conductivity and significantly decreases the absolute stress/strain of the material during multiple lithiation-delithiation processes. The Si–C hybrid composite anode demonstrates a high capacity of 1800 mAh g–1, outstanding cycling stability with capacity retention of 80% over 500 cycles, and fast charge–discharge capability of 12 min. Moreover, the Si–C composite anode exhibits good acceptability in practical LIBs assembled with commercial Li[Ni0.6Co0.2Mn0.2]O2 and Li[Ni0.80Co0.15Al0.05]O2 cathodes.