Tag Archives: SiLeach

Lithium Australia’s VSPC subsidiary achieves world first with mine waste

Lithium Australia’s wholly-owned subsidiary VSPC Ltd has completed a world first; producing lithium-ion battery cathode material and lithium-ion batteries from tri-lithium phosphate that came directly from mine waste.

The feat was achieved using VSPC’s ground-breaking SiLeach® process, which removes the requirement for generation of high-purity lithium hydroxide or carbonate – long seen as one of the most cost-intensive and challenging steps in the manufacture of lithium-ion batteries.

The tri-lithium phosphate was converted to lithium-iron-phosphate cathode material at the advanced electrochemical laboratory and pilot plant facility in Brisbane, Queensland, operated by VSPC.

The cathode material was characterised by X-ray diffraction and scanning electron microscopy and determined to be of similar quality to VSPC-standard lithium-iron-phosphate material. Lithium-ion batteries were subsequently produced and tested under a range of charge and discharge conditions and the cells achieved equivalent performance to VSPC’s advanced cathode powders using lithium carbonate as the manufacturing feed, Lithium Australia reported.

“Battery performance compares very favourably against cells using standard VSPC cathode material produced with industry-standard lithium carbonate,” the company added.

The demonstrated ability to by-pass lithium carbonate and lithium hydroxide as battery precursors provides potential to significantly reduce the cost of battery manufacture, according to Lithium Australia.

“Not only that, the use of mine waste in the battery production cycle can provide greater sustainability to global lithium resources.”

The company is also developing the process for direct production of cathode powders from lithium brines to not only eliminate the requirement to produce high-purity lithium hydroxide or carbonate, but to reduce the requirement for evaporation ponds – one of the more capital-intensive aspects of setting up a lithium brine operation.

Lithium Australia Managing Director Adrian Griffin said: “The most notable aspect of this achievement is its simplicity and ability to streamline the processes and cost required to produce lithium-ion battery cathode materials.

“The broader application to lithium brine exploitation provides enormous potential for that part of the lithium industry, by removing the cost intensive route to lithium hydroxide – the direct use of lithium phosphate to produce cathode powders may do that.”

Lithium Australia’s VSPC subsidiary has been one of the fastest movers in this growing space, completing a large-scale pilot plant to demonstrate its SiLeach process at commercial scale earlier this year.

The company develops processing technology for the manufacture of nano-scale battery cathode powders (via its subsidiary VSPC), the recycling of lithium-ion batteries and low-energy recovery of lithium and other metals from silicates with its 100%-owned SiLeach hydrometallurgical process.

Lithium Australia hoping for SiLeach chemical production this month

The first stage of Lithium Australia’s SiLeach® pilot plant trial at ANSTO’s minerals piloting facility in New South Wales has ended with the production of a lithium-pregnant liquor from lepidolite feed.

Stage two of the pilot will see this liquor processed into lithium chemicals, according to Lithium Australia Managing Director Adrian Griffin.

LIT’s SiLeach process is a halide-accelerated, sulphuric acid digestion system, operated at atmospheric pressure. No roasting is required, significantly reducing the energy footprint when compared with conventional lithium extraction technology. The process also significantly benefits from a range of potential by-product credits.

During stage one of the SiLeach trial, which ran from August 6-16, the plant operated in continuous mode for five days, processing lepidolite concentrate at approximately 4 kg/h through leach, pre-neutralisation and impurity removal stages.

Preliminary data indicate lithium extraction in the leach circuit peaked at 97.5% and averaged 94% for the duration of the trial, according to LIT. Acid addition was 1,300 kg/t and fluorspar addition was 180 kg/t of concentrate feed.

“Leach results exceeded target, supporting the opportunity for concentrate grind size and reagent optimisation during design of the proposed large-scale pilot plant (LSPP, pictured),” the company said.

Operation of the multi-stage impurity removal circuit confirmed the expected rejection of aluminium fluoride (AlF3) in the first stage and encouraged further investigation into the feasibility of recovering an AlF3 by-product from this residue.

The lithium-rich liquor produced during stage one of the trial met purity targets and will be processed through to lithium chemicals in stage two of the trial, due to commence today (September 10). At that stage, calcium and fluorine will be removed and a lithium phosphate produced as a final product.

“Run in an integrated manner, the trial successfully demonstrated continuous operation of Lithium Australia’s proprietary SiLeach process, including full recycle of intermediate process streams.”

The company announced in July it was commencing the first of a two-stage pilot, with the concentrate used as feed for the trial prepared in Perth, Western Australia, under the supervision of Independent Metallurgical Operations. This consisted of lepidolite recovered from mine waste.

Samples of the pregnant solution have been provided to multiple vendors in order to complete solid/liquid separation test work, as well as confirm equipment selection and sizing and support cost estimation for the SiLeach LSPP front-end engineering and design study currently being conducted by CPC Project Design.