Trials achieved up to 60% yields, this is significantly higher than the 30-40% yields currently obtained by spherical producers.
The successful trials are supportive of Black Rock’s strategy of developing a staged low capex mine producing a premium product.
Mahenge spherical graphite returned excellent metrics that exceed lithium-ion battery manufacturer specifications.
John de Vries, interim CEO, commented: “We are delighted that our focus on executing a simple and easy to understand model of a straight forward concentrate business continues to move forward.
“This work validates Mahenge’s product, and reinforces the project’s compelling investment potential.”
Test program summary
The Dorfner Anzaplan test program has delivered exceptional results from Mahenge 99% TGC graphite concentrate, significantly improving upon the 2016 program.
Spherical graphite was made with high yields of up to 60%, a significant improvement on the 30-40% yields currently obtained by the industry.
An adaptation to the current spheronising process has potential to significantly improve yields yet again and this is planned to be trialled.
Importantly the shape, specific surface area and tap densities of the spherical graphite exceed battery maker specifications.
Chemical purification trials exceeded the 99.95% TGC purity levels demanded by battery producers and demonstrated significant reductions in chemical consumption and processing time.
This is attributable to the high initial purity of the precursor Mahenge flake.
Next steps are to distribute bulk quantities of Mahenge concentrates for spheronising testing in commercial plants and provide spherical graphite to end users and provide potential partners with cost and performance data.
The test program validates a critical portion of the process to place Mahenge graphite into the fast growing battery market.
Spherical graphite can be produced, exceeding the strict standards of anode producers and battery manufacturers.
Spherical graphite producers can potentially consistently produce a superior product at higher yields and lower purification costs by using Mahenge graphite.
Black Rock has progressively validated all key aspects of its Mahenge Project including:
- One of the world’s largest graphite resources that simply processes into high purity concentrates;
- A compelling pre-feasibility study with low capex and high margins compared to Tanzanian peers;
- Validation of Mahenge graphite suitability for refractory, expandable and battery use; and
- Validation that Mahenge graphite can make superior battery anodes with higher yields and performance than peers.
These attributes have led to ongoing discussions with end users and potential partners in key markets for product valuation purposes.
Black Rock has also received exceptional feedback from end users regarding the recent 130-cycle battery cell results confirming its graphite has the potential to enable battery manufacturers to produce more stable lithium-ion batteries, at a lower cost with a longer cycle life.