Technology minerals company, Talga Resources Ltd (“Talga” or “the Company”) recently provided an update on its UK battery development programs in Warwick Manufacturing Group’s (“WMG”) Energy Innovation Centre and at Talga’s Cambridge product development labs.
Following successful initial anode results using the Company’s micrographite, and then graphene nanoplatelet (“GNP”) materials, Talga expanded testwork of its graphitic carbons as the active material of Lithium-ion (“Li- ion”) battery anodes (Fig 1).
Talga has received highly encouraging results from 1,200 hours of testwork on a new Li-ion battery anode formulation that combines both its micrographite and GNP materials. The anode exhibited outstanding electrochemical performance across a range of key industry measures, including reversible capacity of ~420mAh/g over a 100 cycle average with a retention of 99.5% and coulombic efficiency of 99.9%.
The capacity measure reflects a ~20% increase in capacity performance compared to commercially available graphite anodes (usually around 330mAh/g). This is significant as increased battery energy density translates into increased range for electric cars and more usage time for a mobile device.
Further, Talga’s WMG test data has enabled the Company to participate in consortia based applications for UK government funding programs and enter a development partnership with Recruit R&D Co Ltd, a major Japanese technology company with extensive experience of the Li-ion battery manufacturing sector.
Talga Managing Director Mark Thompson commented:
“Talga continues to receive strong results from its battery material testwork, utilising our unique ore source with in-house processing and material technologies. The duration of our cycling tests is becoming significant and we are attracting industry attention with our data. This fits our strategy to access more valuable downstream opportunities in the battery value chain in addition to raw material supply. We are exceptionally well placed to benefit in the short term from the booming demand for battery and related conductive materials”.
Following encouraging initial benchmarking tests of Talga’s micrographite and then graphene nanoplatelet (“GNP”) materials in separate coin cell anode test programs (ASX:TLG 10th October 2016 and 7th June 2017), Talga has compiled data from testwork on a new anode formulation trialled at WMG.
The new Li-ion battery anode formulation employs a combination of Talga’s micrographite and graphene (GNP) materials from Talga’s test facility in Germany. The formulation was trialled in coin cells using WMG’s standard N-Methyl-2-pyrrolidone (“NMP”) based anode materials, coated onto copper foils and tested with lithium metal as the counter and reference electrode. The electrodes for the cell were prepared by punching discs from the graphitic carbon coated copper foil and lithium foil. Various components of the cell were then assembled after the addition of the electrolyte. The cells were tested using an industry standard constant current charge discharge technique at a rate of 0.2C.
Figure 1 (Left) Schematic of prismatic or “pouch” cell Li-ion battery showing main components including anode and (Right) graphite-based anode for prismatic Li-ion battery at WMG.
Talga’s anode exhibited outstanding electrochemical performance across a range of key industry measures. Significantly, the anode showed capacity of ~420mAh/g over a 100 cycle average with a retention of 99.5% and coulombic efficiency of 99.9%
The results show a ~20% increase in capacity compared to the theoretical maximum capacity of graphite at 372mAh/g. This outcome is significant given the testwork was conducted using WMG’s standard processes and materials.
Importantly, it can also be seen that the anode charge-discharge profile remained nearly identical at initial cycling and after 1,200 hours of testing with no long term deterioration. In real terms this demonstrates that Talga’s anode could support a Li-ion battery to last longer in between recharge cycles, to enjoy a longer life and to charge and discharge efficiently with minimal loss of energy.
- Highly encouraging endurance test results from new Talga Li-ion battery anode formulation
- New anode successfully cycled for over 1,200 hours while retaining 99.5% capacity
- Talga’s latest combined graphene/micrographite formula shows higher capacity and efficiency than conventional spherical graphite and Talga’s previous anode materials
- Results attract partners across the battery supply chain in Europe via consortia programs targeted at UK government electric vehicle (EV) funding initiatives
- Talga enters partnership with Recruit R&D Co Ltd in Japan to jointly develop Li-ion battery materials for EV markets in Europe and Asia
- Results reinforce Talga’s product strategy which includes the energy sector as a key near-term market