Advances Process Technology For LFPs
Lithium Australia (ASX:LIT) subsidiary VSPC Ltd has developed an optimised process for the production of lithium-ferro-phosphate (LFP) cathode material which can reduce chemical costs by up to 20%.
The company has also reported that lithium phosphate (LP) raw materials produced using VSPC’s optimised process return excellent electrochemical results, confirming the flexibility of the process for a range of lithium feed materials.
In October 2019, at its Brisbane research and development facility, VSPC initiated a project to develop low-cost raw material options for its proprietary process for cathode material synthesis.
The project is being co-funded by the Australian Manufacturing Growth Centre (AMGC), a not-for- profit organisation established by the Australian federal government to support the development of world-leading advanced manufacturing in Australia.
Project objectives include the following.
* Demonstrate the technical feasibility of producing advanced LFP cathode material via an optimised process that, significantly, requires less chemical reagents (the process has been dubbed ‘VSPC-RC’, where ‘RC’ is an acronym for ‘reduced cost’).
* Evaluate the techno-economic feasibility of LFP synthesis using lower-cost raw materials such as iron sulphate, iron oxides and LP from several sources, among them:
* the Company’s patented SiLeach process (which targets lepidolite);
* the Company’s LieNA® process (which targets fine and/or low-grade spodumene),
and
* mixed metal dust (‘MMD’) derived from spent lithium-ion batteries (‘LIBs’) by Company subsidiary Envirostream Australia Pty Ltd, a mixed- battery recycling entity located in Melbourne, Victoria.
Outcomes
With stage 2 of the project now complete, VSPC is pleased to report the following.
* The VSPC-RC process was operated at laboratory and pilot scale to produce advanced LFP cathode material via a simplified process operation and with consumption of chemical reagents significantly reduced.
Such process refinements could reduce reagent costs by 15-20%, depending on project location, which is significant given that prices for chemical reagents account for more than half the total costs of manufacturing LFP cathode material.
* A further 5-10% reduction in chemical costs was achieved by manufacturing iron oxalate (normally a major reagent cost) from base chemical reagents that included iron sulphate and iron oxide materials.
* The optimised VSPC-RC process was applied to LP from several sources to produce LFP cathode materials. Those sources included:
* refined LP produced via SiLeach;
* LP produced from fine spodumene using LieNA, and
* refined LP produced using Envirostream MMD as feed.
Importantly, the advanced LFP cathode material VSPC produced demonstrated excellent electrochemical performance (equivalent to or exceeding that of VSPC’s standard LFP material); viz:
# specific capacity = 158 milliampere hours per gram (‘mAh/g’) at a 0.1C discharge rate in coin cells (a 0.1C discharge rate means that the discharge current will discharge the entire battery in ten hours), and
# the physical properties for electrode coating were excellent.
Electrochemical discharge curves for the advanced LFP cathode material produced via the VSPC-RC process from SiLeach-generated LP are shown in the graph below (160 mAhg-1 at 0.1C discharge rate).
Lithium Australia MD, Adrian Griffin, said these results further support the cost-competitiveness of the VSPC-RC process, as well as its flexibility in terms of application to several lithium raw materials, including lithium carbonate, lithium hydroxide and LP.
Indeed, LP offers a direct, efficient route from both mineral and recycled sources to the production of LFP cathode material for the fastest growing sector of the LIB market.
“Using easily available and lower-cost base reagents in the manufacture of LFP can have a profound impact on the price of production. It is imperative that VSPC maximises its competitive advantages in terms of both reagent inputs and physical manufacturing costs,” Mr Griffin said.
“The AMGC grant has been the catalyst in evaluating lower-cost options that may not otherwise have been considered. In many cases, such options are location-specific, so the results of this study may well lead to Australia being seen as a more competitive place for the production of LFP batteries.”
