Australia-based Graphene Manufacturing Group (GMG) has reported a significant increase in the energy density of its graphene aluminium-ion battery technology, as it moves closer to commercialisation of ultra-fast charging cells.
In an update released on April 15, GMG said its “G+A CELLS” have nearly doubled their energy density since December 2025, rising from 26 Wh/kg to 49 Wh/kg under testing conducted with the Battery Innovation Center.
The company is developing the technology with the University of Queensland under a joint development agreement with mining group Rio Tinto.
At slower charge rates (1C), GMG reported energy density of 101 Wh/kg when charging to full state of charge—up from 58 Wh/kg in its previous update—alongside a nominal voltage increase to around 3.2 V.
The technology is designed around ultra-fast charging capability, with cells able to charge in approximately six minutes (10C) while maintaining performance over “hundreds of cycles”, according to the company.
GMG is positioning the chemistry as an alternative to high-power lithium-ion variants such as lithium titanate oxide (LTO), which are among the few existing battery types capable of comparable charge rates but are typically sold at a premium.
Bob Galyen, GMG non-executive director and former CTO of CATL, said the technology could alter system-level design assumptions:
“With the possibility of charging from empty to full in around six minutes, this chemistry fundamentally changes how designers can think about electric vehicles, consumer electronics, and stationary storage.”
Graphene aluminium-ion as a lithium alternative
A key aspect of the system is its use of aluminium and graphene rather than lithium-based chemistries. GMG said it has developed a chloride-free, non-corrosive electrolyte alongside new cathode and anode structures that enable stable high-rate charging.
Both electrodes are based on aluminium foil substrates, eliminating the need for copper and potentially reducing cost and weight relative to conventional lithium-ion designs.
The company also indicated that its cells may not require thermal management systems or the fire-resistant metal casings typically associated with lithium-ion packs, opening the possibility of lighter plastic battery enclosures.
GMG is targeting heavy mobile equipment as an initial application, citing key performance thresholds including sub-six-minute charging, energy density above 100 Wh/kg at 1C, and intrinsic safety benefits from the absence of lithium.
The company said it has “largely met” these requirements and is now progressing towards the next stage of development, including customer testing and manufacturing planning.
Craig Nicol, GMG managing director and CEO, described the latest results as a “significant step up” from late 2025, adding that the company is preparing for “the next stages of the battery maturation program”.
The technology currently sits at battery technology readiness level (BTRL) 4, with further validation work required on cycle life, temperature performance and safety testing. GMG expects to begin customer trials in 2026, followed by small-scale commercial production in 2027.
Looking ahead, GMG said it believes that graphene aluminium-ion could reach energy densities above 160 Wh/kg at 1C and more than 80 Wh/kg under six-minute charging with further optimisation.
While still at an early stage, the company argues that its graphene aluminium-ion platform could complement or partially displace lithium-ion systems in applications where rapid charging, high power density and reduced reliance on critical minerals are key design drivers.
