Testing shows Talga graphene silicon boosts capacity of Li-ion battery anode; Safevolt project
25 October 2018
Australian advanced materials technology company Talga Resources Ltd announced positive initial test results from the development of its graphene silicon lithium-ion anode in the UK.
The results are the first under Talga’s UK Government funded “Safevolt” project—a Talga-led program run in conjunction with consortia partners, Johnson Matthey, the University of Cambridge and manufacturing research group, TWI. Under Safevolt, Talga is developing a high energy graphene silicon anode product, termed Talnode-Si, targeting significantly higher capacity than state of the art commercial graphite anodes.
Highlights of initial test results include:
~50% higher reversible capacity (~550mAh/g) than commercial graphite (~350mAh/g) • Coloumbic efficiency of 99.3% - 99.8%
95% reversible capacity (after 45 cycles - tests ongoing)
Major Li-ion battery manufacturers are requiring higher energy density via increasing amounts of silicon in graphite anodes, however silicon use is hindered by a range of battery life and stability problems. These test results show Talnode-Si with graphene is effective in stabilizing the silicon as it expands, maintaining battery life while enabling much higher energy density.
The Safevolt project is an enabler for industry wanting higher Li-ion battery capacity above the level of standard graphite (exceeding maximum 372 mAh/g).
In theory, a silicon anode is capable of providing approximately 10 times the gravimetric (or 3 times the volumetric energy) of the standard graphite anode Li-ion battery. However, silicon experiences drastic volume change during charge and discharge cycles, causing sharply shorter battery life and/or failure.
The three keys to solving silicon anode life issues are stabilising the silicon as it expands, maintaining conducting percolation and solid electrolyte interface control.Further cycling tests and optimization of Talnode-Si is underway at Talga’s battery material facility in the Maxwell Centre at Cambridge University in the UK. Interim samples are being prepared for delivery to end users in Asia under confidentiality and material transfer agreements. Progress on the other Faraday projects, “Scale-up” and “Sodium” is continuing according to plan and updates will be provided as the programs proceed through their individual project stages.
Talga Resources Ltd is an advanced materials technology company enabling stronger, lighter and more functional products for the multi-billion dollar global coatings, battery, construction and polymer composites markets via graphene and graphite products.