Lithium Australia has been in the lithium space for about five years. It is regarded as a founding member of Australia’s modern lithium sector, built largely around a cluster of spodumene deposits in Western Australia (WA). During that time, the lithium sector has been transformed by burgeoning demand from the global lithium-ion battery (LIB) market. Australian miners have responded by establishing a number of conventional hard-rock lithium mines in anticipation of a massive surge in battery consumption globally.
Lithium Australia, however, has taken a long-lens view of development in the sector. Having noted that active producers discard high levels of lithium mica material as waste, the company began developing an innovative technology to effectively process that mica.
“Mining for other commodities, such as tin, tantalum and tungsten, also produces quite substantial streams of lithium that are discarded as waste – not as spodumene waste but as lithium micas,” says Adrian Griffin, managing director of Lithium Australia.
“One reason for this is the fact that micas contain lower grades of lithium than spodumene, and those lower grades haven’t until now been capable of covering the operating costs required for conventional processing.
“We saw an opportunity to develop a processing technology that could capitalise on lower-grade lithium materials … which drove us to focus on mineral processing rather than exploration,” he explains.
As a consequence, Lithium Australia has evolved into a technology play with a very clear mindset – ‘Let the miners explore and extract; we’ll handle the crucial processing stage’ – and the aim of supplying enough battery chemicals to meet growing demand.
That said, Lithium Australia’s SiLeach® technology is backed by one of the largest lithium exploration portfolios in the world, which begs the question: is Lithium Australia a process developer, an explorer or both?
Griffin responds by explaining Lithium Australia’s current strategy: gaining access to waste streams lessens exposure to mining costs, because someone else has already removed the material and would otherwise discard it as waste.
Although Lithium Australia can cut attractive deals with miners for their tailings, however, reliance on third-party feed, particularly non-lithium feeds such as tantalum, means that any price volatility could have a significant impact on supply.
“We decided the best way around this potential problem was to develop an exploration portfolio as an insurance policy. If you take the view that there’s more lithium going to waste than ever gets into the supply chain, then there’s no justification for digging another hole – but you certainly can justify being a primary producer if your supply is interrupted.”
With that in mind, Lithium Australia has assembled a diverse exploration portfolio spread across major lithium provinces globally.
“We’re very heavily invested in Australia and that’s not surprising, given that this country currently produces about 40% of the world’s lithium,” explains Griffin. Lithium Australia has formed joint ventures with a number of Australian lithium companies and has stakes of various sizes in several WA-based projects, along with a few in Queensland and South Australia and one in the Northern Territory.
Lithium Australia also has a controlling interest in a substantial lithium clay project in Mexico and has entered into a joint venture with Tin International AG on a project in Germany. That project is estimated to contain an inferred mineral resource of 25 million tonnes at 0.45% lithium oxide, making it an enticing prospect – the lithium is contained in mica, liberated during the extraction of tin.
Having taken the long view in the Australian lithium space, Lithium Australia observed that conventional processing of spodumene concentrate incorporated an energy-intensive roasting stage.
Roasting has also been considered the only way to refine hard-rock lithium material into usable chemicals such as lithium carbonate. Until recently, the process has been undertaken exclusively in China but this is about to change, with a new refinery under construction in Perth.
The current method of producing lithium chemicals is as follows. Spodumene is mined in, say, Australia and shipped to China, where it is roasted at a high temperature, baked in sulphuric acid and then leached with water. Subsequent chemical steps refine the solution until eventually lithium carbonate is produced.
“When we looked at the roasting method we concluded that, although the price of lithium carbonate was much lower then than it is today, you can’t roast with a feed grade that’s only half that of spodumene, because you can’t pay the energy bill,” says Griffin.
“So, the first thing was to ensure that the process we developed had a low energy footprint. Then we looked at whether it’s possible to pull anything else, apart from lithium, out of the resulting process solutions.”
The company concluded that the only way to achieve both ends was by way of a hydrometallurgical flowsheet, and that is how SiLeach® was conceived.
In a nutshell, the SiLeach® process involves slowly mixing lithium minerals with calcium fluoride before sulphuric acid is added to dissolve the mix into a recoverable form that contains several types of product, including the sought-after lithium chemicals.
As well as being a significantly cheaper means of producing battery-grade lithium, the SiLeach® process for treating micas also creates a number of valuable by-products, including potassium sulphate. In fact, lithium micas typically contain 10-12% potassium oxide, which is greater than that of contained lithium oxide which is generally 2-4%.
“It’s important to capitalise on this potassium by-product credit. We do that by precipitating potassium as potassium sulphate, which goes straight into the fertiliser industry, and that alone covers around 20-30% of the operating costs.”
Additional by-product credits to be gained through use of the hydrometallurgical process include various aluminium chemicals and sodium silicate, with a few lesser-known chemicals also adding depth to the project economics.
To summarise, the low energy profile of the SiLeach® process is bolstered by the range of commercially viable by-products that can be extracted alongside the lithium chemicals – a sweet combination for Lithium Australia.
Griffin believes that once by-product credits are factored in, the company could become one of the cheapest lithium producers in the world, even competing with the brine producers in the fabled lithium triangle of South America.
Lithium Australia has developed a way of effectively processing ‘waste’ material into lithium chemicals, but the purity of the end product remains an important consideration. Therefore, it is not unreasonable for potential end-market users to question the purity of Lithium Australia’s product: anything below the industry benchmark of 99.5% hinders the chemical’s performance in lithium-ion batteries.
With that in mind, Lithium Australia has conducted a series of test-tube and bench-scale tests for its SiLeach® process, as well as operating a pilot plant designed and built by the Australian Nuclear Science and Technology Organisation. As a result of those continuous pilot tests, says Griffin, the company has verified its ability to produce ‘battery-grade’ lithium carbonate on a continuous basis.
Lithium Australia is now ploughing ahead with a large-scale pilot plant (LSPP) designed on a ratio of 1:10 to the eventual full-scale plant.
The LSPP, to be constructed in WA, will take in feed from the Lepidolite Hill deposit located just South of Coolgardie. Lithium Australia has a joint venture with Focus Minerals at Lepidolite Hill, but the plant will also take in feed from another source currently being negotiated by the parties concerned.
Access to the plant site, where the infrastructure required is already in place, including power, water and gas supplies and road and rail access, is another matter under discussion.
“We’re also negotiating the acquisition of long-lead-time items for the plant,” reveals Griffin. “Construction will take around 18 months, but that time frame is dictated by the delivery of those long-lead-time items. We anticipate seeing first production of lithium chemicals in 2020.”
In other major news for Lithium Australia, the company has recently confirmed it will move into cathode manufacturing and battery recycling on the basis of its acquiring 99.7% of the Very Small Particle Company (VSPC), an outfit Griffin believes is one of the most advanced cathode-powder manufacturing entities in the world.
VSPC was founded by a small group of academics with considerable intellectual acumen. For 14 years, they researched cathode powder production technology before setting up a world-class facility in Brisbane, Australia, to demonstrate cathode-powder manufacture.
“We took some of those cathode powders, used them to produce new batteries and had the batteries independently tested against industry standards in a lab in Germany. They outperformed industry standards.
“We think there’s enormous value in VSPC, and we’re rebuilding the company with a view to re-commissioning VSPC’s Brisbane pilot plant in the next couple of months,” Griffin reveals.
Perhaps most interestingly, after some number crunching with respect to the logistics of battery manufacturing, Griffin believes the most profitable part of the process lies in the final stage, in which lithium carbonate becomes cathode powder.
“It’s the sweet spot in the value chain, and we certainly hope we can capitalise on that. Under those conditions [the venture with VSPC], we’ll become the only company capable of taking mine waste right through to cathode powder.”
During the last five years, then, Lithium Australia has developed an innovative processing technology capable of transforming waste products into lithium chemicals for the voracious battery market, along with several valuable by-products.
In addition, the company is developing an ability to transform lithium chemicals into cathode powder through its purchase of VSPC, a move that will make it one of only a few fully integrated lithium cathode powder producers in the world.