Battery grade HPMSM is used to make lithium-ion batteries for electric vehicles.
The Butcherbird project has resources of more than 263 million tonnes of manganese ore.
The recent high-purity manganese flowsheet optimisation test work confirmed the solution showed rapid extraction at ambient temperature and atmospheric pressure, with the reagent used reducing process complexity and carbon intensity.
E25 reported recoveries of up to 97% manganese.
E25 managing director Justin Brown said the resumption of the flowsheet optimisation test program was a critical component of finalising the battery grade manganese sulphate pre-feasibility study scheduled for completion in 2021.
He said the work also confirmed the suitability of the concentrate produced from the stage 1 beneficiation circuit for conversion to HPMSM.
Brown said as part of E25's multi-stage development strategy work was focusing on a stage 2 expansion of the concentrate business, followed by a stage 3 development to convert the concentrate material into HPMSM for electric vehicle batteries.