Battery minerals company Lithium Energy (ASX:LEL) reports it has started drilling program at the Burke Tenement (EPM 25443), with the objective to upgrade the Burke deposit from a JORC Inferred Mineral Resource to a higher standard JORC Indicated Mineral Resource category.
The company reports the drilling program will comprise a combination of reverse circulation (RC), diamond core and geotechnical holes totalling 2,000m across 20 RC holes, to a maximum depth of 110m and 600m across 6 diamond holes, to maximum depths of 120m.
The diamond holes have been planned to provide a sufficient representative core sample of the Burke deposit, which will form the basis of an extensive metallurgical and Purified Spherical Graphite (PSG) testwork and development program, to support a planned engineering study for the Burke Project.
Lithium Energy has also received all environmental and Heritage and Cultural permits and approvals to undertake a drilling program at the Corella Tenement (EPM 25696), which will test the extent of graphite mineralisation identified through the previously conducted Electro Magnetic (EM) surveys anode testwork recently conducted by CSIRO has shown that graphite from the Burke Graphite Project in Queensland has ‘excellent’ lithium-ion battery potential.
The company also announces the results of anode testwork recently conducted by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and provide an update on further development of its 100% owned Burke Graphite Project.
This project was made possible through the CSIRO Kick-Start, an initiative that provides funding and support for innovative Australian start-ups and small businesses to access CSIRO’s research expertise and capabilities to help grow and develop their business.
The company says the Burke Graphite project was made possible through the CSIRO Kick-Start initiative which provides funding and support for innovative Australian start-ups and small businesses to access CSIRO’s research expertise and capabilities to help grow and develop their business.
Lithium Energy Executive Chairman William Johnson says: “The current round of testwork conducted by CSIRO is highly encouraging as it establishes the potential of graphite from Burke to be refined into a high-value anode material suitable for use in lithium-ion batteries.
With the imminent commencement of drilling at the Burke tenement and subsequently at the Corella tenement, Lithium Energy is rapidly accelerating the development of the highly attractive graphite side of its battery minerals business.”
Lithium Energy reports CSIRO has undertaken characterisation, purification and spheronisation testwork on natural Burke Graphite to determine its suitability for use as a battery anode material.
In depth characterisation of Burke Graphite concentrate produced from previous drill core samples taken from the Burke Tenement using laboratory floatation was first conducted by CSIRO to determine the concentration of various impurities elements via XRF, as well as using an automated mineralogy analyser to determine the mineralogy of the residual impurities within the natural graphite concentrate over 95% total graphitic carbon (TGC).
The 4 major impurities in the Burke Graphite concentrate identified were micas, feldspars, clay minerals and silica which the company says is ‘typical’ for graphite deposits.
CSIRO then conducted several different purification techniques and processes on the Burke Graphite concentrate to remove these impurities with preliminary results achieving a purity of 99.94% TGC which closely compares to ‘typical’ industry requirements of over 99.95% TGC for anode material.
Spheronising testwork was conducted on unpurified Burke Graphite in a bench scale NARA NHS-0 Hybridiser, producing spheronised graphite particles with a d501 of between 15um to 17um and a Tap density of 0.92g/cm-cubed which the company says is equivalent to the ‘typical’ industry benchmark for Tap Density f anode ready material for this size distribution.
This unpurified spheronised material was then used for the preparation of natural graphite anodes for electrochemical testing. These electrodes showed electrochemical capacity of 344mAh/g to 356mAh/g at 0.1C-square cycle rate, which compares with the typical commercial electrode baseline results of over 350mAh/g.
Lithium Energy reports these preliminary results achieved by the CSIRO testwork are considered ‘highly encouraging’ as they closely approach or meet the relevant industry benchmarks typically required for lithium-ion battery anode material. Furthermore, the company considers these results are positive given the electrochemical testing of natural graphite anodes were made from spheronised Burke Graphite without the benefit of final purification or any coating material being applied, both of which would typically improve cell performance even further.
Based on these preliminary results, the company is planning further anode development testwork with the objective of producing samples of purified spherical graphite (PSG) material which meet or exceed relevant industry performance benchmarks for prospective customers to evaluate for use as anode material in lithium-ion batteries.
The company also reports following the completion of the drilling program at the Burke Tenement, it has proposed an initial drilling program at the Corella Tenement of around 2,000m of reverse circulation (RC) and around 200m of diamond drilling.
This program has been designed to test the extent of graphite mineralisation with the objective of delineating a maiden inferred mineral resource at Corella, which will build upon a previous surface sampling program that indicated multiple occurrences of ‘high-grade’ graphite up to 14.8% TGC together with a ground electromagnetic (EM) survey that identified the potential for ‘significant’ graphite mineralisation.
Subject to the Queensland wet season and drill rig availability, the Corella drilling program is expected to be completed in Q1 2023.
Lithium Energy is an ASX-listed minerals company developing its flagship Solaroz Lithium Brine Project in Argentina and the Burke Graphite Project in Queensland.
The Burke Graphite Project is located in the Cloncurry region of north central Queensland and contains a defined inferred mineral resource of 6.3 million tonnes @ 16% TGC for 1 million tonnes of contained graphite.
Within the mineralisation envelope, there is an included ‘higher grade’ material of 2.3 million tonnes @ 20.6% TGC for 464,000 tonnes of contained graphite which will be investigated further.
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