In the battle of the batteries, lithium-ion technology is the reigning champion, powering that cell phone in your pocket as well as an increasing number of electric vehicles on the road. Charging an electric car costs much less than paying for an equivalent amount of gasoline. Electric cars can be built with a fraction of moving parts, which makes them cheaper to maintain.
So why aren’t electric cars everywhere already? It’s because batteries are expensive, making the upfront cost of an electric car much higher than a similar gas-powered model. And unless you drive a lot, the savings on gasoline don’t always offset the higher upfront cost. In short, electric cars still aren’t economical.
Sand battery gives three times more battery life
This alternative type of lithium-ion battery uses silicon to achieve three times better performance than current graphite li-ion batteries. The battery is still lithium-ion like the one found in your smartphone, but it uses silicon instead of graphite in the anodes.
Scientists at the University of California Riverside have been focused on nano silicon for a while, but it's been degrading too quickly and is tough to produce in large quantities. By using sand it can be purified, powdered then ground with salt and magnesium before being heated to remove oxygen resulting in pure silicon. This is porous and three-dimensional which helps in performance and, potentially, the life-span of the batteries. We originally picked up on this research in 2014 and now it's coming to fruition.
Silanano is a battery tech start up that's bringing this technique to market and has seen big investment from companies like Daimler and BMW. The company say that its solution can be dropped into existing lithium-ion battery manufacturing, so it's set for scalable deployment, promising 20 per cent battery performance boost now, or 40 per cent in the near future.
Capturing energy from Wi-Fi
While wireless inductive charging is common, being able to capture energy from Wi-Fi or other electromagnetic waves remains a challenge. A team of researchers, however, has developed a rectenna (radio wave harvesting antenna) that is only several atoms think, making it incredibly flexible.
The idea is that devices can incorporate this molybdenum disulphide-based rectenna so that AC power can be harvested from Wi-Fi in the air and converted to DC, either to recharge a battery or power a device directly. That could see powered medical pills without the need for an internal battery (safer for the patient), or mobile devices that don't need to be connected to a power supply to recharge.
Energy harvested from the device owner
You could be the source of power for your next device, if research into TENGs comes to fruition. A TENG - or triboelectric Nano generator - is a power harvesting technology which captures the electric current generated through contact of two materials.
A research team at Surrey's Advanced Technology Institute and the University of Surrey have given an insight into how this technology might be put into place to power things like wearable devices. While we're some way from seeing it in action, the research should give designers the tools they need to effectively understand and optimise future TENG implementation.
Gold nanowire batteries
Great minds over at the University of California Irvine have cracked nanowire batteries that can withstand plenty of recharging. The result could be future batteries that don't die.
Nanowires, a thousand times thinner than a human hair, pose a great possibility for future batteries. But they've always broken down when recharging. This discovery uses gold nanowires in a gel electrolyte to avoid that. In fact, these batteries were tested recharging over 200,000 times in three months and showed no degradation at all.
Solid state lithium-ion
Solid state batteries traditionally offer stability but at the cost of electrolyte transmissions. A paper published by Toyota scientists writes about their tests of a solid state battery which uses sulphide superionic conductors. All this means a superior battery.
The result is a battery that can operate at super capacitor levels to completely charge or discharge in just seven minutes - making it ideal for cars. Since its solid state that also means it's far more stable and safer than current batteries. The solid-state unit should also be able to work in as low as minus 30 degrees Celsius and up to one hundred.
The electrolyte materials still pose challenges so don't expect to see these in cars soon, but it's a step in the right direction towards safer, faster-charging batteries.
Scientists in Japan are working on new types of batteries that don't need lithium like your smartphone battery. These new batteries will use sodium, one of the most common materials on the planet rather than rare lithium – and they'll be up to seven times more efficient than conventional batteries.
Research into sodium-ion batteries has been going on since the eighties in an attempt to find a cheaper alternative to lithium. By using salt, the sixth most common element on the planet, batteries can be made much cheaper. Commercialising the batteries is expected to begin for smartphones, cars and more in the next five to 10 years.
But a novel manganese and sodium-ion-based material developed at The University of Texas at Dallas, in collaboration with Seoul National University, might become a contender, offering a potentially lower-cost, more eco-friendly option to fuel next-generation devices and electric cars.
"Lithium is a more expensive, limited resource that must be mined from just a few areas on the globe," Cho said. "There are no mining issues with sodium -- it can be extracted from seawater. Unfortunately, although sodium-ion batteries might be less expensive than those using lithium, sodium tends to provide 20 percent lower energy density than lithium."
The energy density, or energy storage capacity, of a battery determines the run time of a device.