“If we succeed in developing this technology, we are facing the ultimate breakthrough for electric cars, because in practice, the energy density of Li-air batteries will be comparable to that of petrol and diesel, if you take into account that a combustion engine only has an efficiency of around 30 per cent,” says Tejs Vegge, senior scientist in the Materials Research Division. The batteries feature a lithium electrode and a porous carbon cathode — during electrical discharge, the battery allows oxygen to react with lithium to create lithium peroxide, and during charging the action is reversed to release the oxygen.
One end of the battery casing is left open so that oxygen can flow freely in and out during the process. Although the battery technology has been proven to work in laboratory situations, the researchers have a handful of hurdles they will need to cross in order to bring this technology to market. They are currently trying to double the energy capacity of the battery, and they have also realized that the battery can get choked by regular air — the researchers have found best results with pure oxygen, which can limit the battery’s supply of air, causing it to stop working. One last hurdle is charging — current Li-air prototypes can only handle 50 charges, and researchers need them to handle upwards of 300 to be commercially viable.
New Graphene Lithium-Air Batteries Increase Energy Density and Decrease Costs
by Brit Liggett
In a not so distant future the concept of electric vehicle range anxiety may completely disappear thanks to research by laboratories across the nation. Technology took a step closer to that future today with the invention of a new type of Lithium-Air batteries made from graphene bubbles that have an energy density so high they could take an electric vehicle 300 miles between charges. In addition to the extended battery life, the batteries are made without precious metals like platinum, which greatly reduces production cost.
In order to create the graphene bubbles the researchers mixed graphene — a form of carbon — with a binding agent. They then released the solution into water and mixed it to create tiny bubbles, and the graphene and the binding agent formed hard shells around the water bubbles. When the bubbles were popped, graphene shells about 10 times smaller than the width of a human hair were left behind. The resulting structures can store 15,000 milliamp hours per gram of graphene – a much higher energy density than is possible with other materials.
However a few obstacles stand in the way of bringing this technology to the market. For one, the batteries perform best in an oxygen-only environment – the moisture in ambient air interferes with the reaction and diminishes the battery capacity. In addition, the technology is not fully rechargeable yet – something the researchers are working hard to remedy. “This hierarchical structure of self-assembled graphene sheets is an ideal design not only for lithium-air batteries but also for many other potential energy applications,” said Dr. Jie Xiao, a leader of the study at PNNL. To top it all off, the lithium-air batteries with graphene bubbles are lighter in weight than current batteries. Less weight, less cost and more energy sounds like the future to us.
New Carbon Network EV Batteries Charge Up to 120x Faster
by Marc Carter
Toyota Developing Revolutionary Solid-State and Lithium-Air Electric Vehicle Batteries, Aims to Launch by 2020
by Taz Loomans
Today’s lithium-ion batteries are expensive and bulky – which is why Toyota is currently developing two new types of ultra-efficient batteries to power its electric vehicles. Toyota is conducting research on solid-state batteries and lithium-air batteries that promise to be more compact and be able to store more energy than lithium-ion batteries – and the automaker plans to switch to these new technologies by 2020.
Two types of lithium-ion batteries are commonly used in electric vehicles: lithium-ion-phosphate batteries and lithium-polymer batteries. The problem with lithium-ion batteries is that more than half of their size is dedicated to materials that don’t even store energy, such as insulators and materials designed to protect and cool the energy-storing components.
Solid-state batteries – one of the battery types that Toyota is researching – provide a host of benefits. They use a solid electrolyte and solid electrodes, unlike most batteries, which use liquid electrolytes. A significant benefit of these batteries is that the lack of liquid enables them to be connected to each other without being placed in their own individual cases, which makes for more compact packaging. Solid-state batteries also have the potential to out-perform lithium-ion batteries, and they can be created using thin films.
Lithium-air batteries have the theoretical potential to store 50 times more energy than typical lithium-ion batteries. Lithium-air batteries use oxygen in the air as a cathode active material. According to Toyota, “they achieve weight savings and better energy density than solid batteries by changing negative-electrode material into metallic lithium from black lead.”Φ
Marc Carter grew up in Los Angeles listening to the sound of vintage Chevys and Fords being tweaked in his parents’ garage. Today he calls San Francisco his home, but his obsession about the automotive world is stronger than ever. Five years ago he founded The Torque Report, the “go-to” destination for late and breaking news on the auto industry.
Brit Liggett is a freelance video producer and a writer. She has worked for Inhabitat.com, Ecouterre.com, Adobe, Comcast, The Lazy Environmentalist, The Washington Post Co., Newsweek.com, CNN, AMC, Entertainment Tonight and the OCRegister.com.
Taz Loomans is a licensed architect who is the principal at an architecture and development company called Blooming Rock Development. She is also a writer and publishes the award-winning Blooming Rock blog which focuses on urbanism, sustainability and architecture.