That will allow Renascor to tap into high-value industrial markets during Siviour's first phase of production.
Flowsheet parameters of the mineral processing plant were increased to take production of size fractions bigger than 150 microns up to about 60% of total production from a projected 17% to 27%.
Siviour is the upstream part of Renascor's planned Battery Anode Material project in South Australia.
The adjustment to the flowsheet parameters was based on locked-cycle tests.
The change will reduce Renascor's reagent costs.
The company has also adjusted the scope of front-end engineering works to incorporate the revised product mix.
Renascor managing director David Christensen said the revisions were part of a plan to optimise and accelerate the production of graphite from the Siviour project in alignment with projected near-term shortages in supply.
"As we look to conclude favourable agreements with offtake partners and advance to a final investment decision, we intend to take advantage of our favourable cash position to continue to accelerate the development of Siviour with a view to minimising the planned construction period and to develop an early mover advantage as a secure, long-term provider of Australian graphite products," he said.