Graphene Manufacturing Group (GMG), located in Brisbane, Australia, developed graphene aluminum-ion battery cells that the company claims charge 60 times faster than the best lithium-ion cells, and can hold three times the energy of the best aluminum-based cells.
The graphene aluminum-ion cells were created using breakthrough nanotechnology from the University of Queensland’s (UQ) Australian Institute for Bioengineering and Nanotechnology. The battery cells use nanotechnology to insert aluminum atoms inside tiny perforations in graphene planes. The specific aluminum-ion battery composition consists of an aluminum foil anode, a graphene cathode, and an aluminum-chloride electrolyte. No lithium, copper, manganese, or cobalt are used in the design.
If GMG’s research proves fruitful, the graphene aluminum-ion batteries could provide an answer to a lot of the concerns surrounding EV car batteries. They would provide a longer range and charge much faster. They would also be a more sustainable solution, as the batteries are easier to recycle due to their stable base materials. The new graphene aluminum batteries are also safer, with no upper ampere limit to cause spontaneous overheating.
The peer-reviewed publication, Advanced Functional Materials, concluded the cells had “outstanding high-rate performance (149 mAh g−1 at 5 A g−1), surpassing all previously reported AIB cathode materials.” Testing also shows the coin-cell validation batteries last three times longer than lithium-ion versions.
Though GMG’s cells are not the only graphene aluminum-ion cells under development, according to GMG Managing Director Craig Nicol they were easily the strongest, most reliable and fastest charging. “It charges so fast it’s basically a super capacitor,” Nicol said. “It charges a coin cell in less than 10 seconds.”
Nicol also says the new battery cells deliver far more power density than current lithium-ion batteries, without the cooling, heating, or rare-earth problems that lithium batteries commonly face. “So far there are no temperature problems. Twenty percent of [the space taken up in] a lithium-ion battery pack [in an EV] has to do with cooling them,” said Nicol. “There is a very high chance that we won’t need that cooling or heating at all. It does not overheat and it nicely operates below zero so far in testing.”
The new cell technology could also be industrialized to fit inside current lithium-ion housings — like the Volkswagen Group’s MEB architecture — heading off problems with car-industry architectures that tend to be used for up to 20 years. Currently the focus is on coin cells because GMG has a readily available manufacturing system and end product specification to sell as an interchangeable battery to existing lithium batteries. After making coin cells, the company plans to focus on pouch packs, as the company believes they will have an advantage over existing lithium pouch packs with the very fast charging time of the aluminum-ion cells.
“We intend to make an interchangeable battery (same voltage and form factor/shape) as the lithium batteries and hence they can be swapped out and use grandfather electronics and charging infrastructure reducing the adoption risk, timeline and cost for the intended market,” said Nicol.
Aluminum-Ion Battery Development Boom
Around the world projects to develop aluminum-ion batteries are in full swing. This includes a collaboration between China’s Dalian University of Technology and the University of Nebraska, and others from Cornell University, Clemson University, Stanford University, the Zhejiang University’s Department of Polymer Science and the European Alion industrial consortium.
The differences between the various R&D projects are highly technical, but the GMG cells use graphene made from its proprietary plasma process, rather than traditional graphite sourcing. According to the company, their result is three times the energy density of the next-best cell, which was developed at Stanford. GMG in collaboration with UQ report an energy density of 150-160 with a power density measuring approximately 7,000 W/kg. In comparison, Stanford’s natural graphite aluminum-ion technology delivers around 68.7 Wh per kg and 41.1 W/ kg and its CVD graphitic foam aluminum technology goes up to 3000 W/kg.
“This is a real game-changing technology which can offer a real alternative with an interchangeable battery technology for the existing lithium-ion batteries in almost every application with GMG’s graphene and UQ’s patent-pending aluminum ion battery technology, ” said Dr. Ashok Nanjundan, chief scientific officer at GMG. “The current nominal voltage of our batteries is 1.7 volts, and work is being carried out to increase the voltage to directly replace existing batteries, which leads to higher energy densities.”
Aluminum Battery Technology Could Replace Lithium
When a cell recharges, aluminum ions return to the negative electrode and exchange three electrons per ion, lithium does the same exchange but at the rate of only one per second. Nicol describes GMG/UQ’s aluminum ion technology as a direct replacement (for lithium ion technology) that charges so fast it could be compared to a super capacitor. “Some lithium-ion cells can’t do more than 1.5-2 amps or you can blow up the battery, but our technology has no theoretical limit,” he said.
The aluminum-ion cells use hardly any exotic materials, and the environmental, financial, and safety benefits make this technology a viable alternative to lithium-ion. Lithium prices have risen from $1460.00 per metric tonne in 2005 to $13,000 in May 2021, while aluminum prices only changed from $1,730.00 to $2,078.00 in the same time period. Furthermore, unlike lithium-ion cells, as mentioned the graphene aluminum-ion cells do not require the use of copper, which costs around $8,470.00 per tonne.
Since GMG manufactures their own graphene, they are confident that they will be able to make it in the future at the required costs to make the graphene aluminum battery economically. The company says their process allows for lower manufacturing costs, as they take very low-cost readily available natural gas to manufacture the graphene.
“There are approximately 15 kg of carbon atoms in every gigajoule (GJ) or mmbtu in natural gas (depending on your gas composition), and in most countries in the word — 1 GJ or 1 mmbtu is less than $10 — delivered to where you need in an existing pipeline,” said Nicol.
GMG plans to bring graphene aluminum-ion coin cells to market late this year or early next year, with automotive pouch cells planned to roll out in early 2024.