An Australian company called Cobre Montana is looking to commercialize a lithium extraction process that it says could end the prospect of supply bottlenecks forever.
The process is less energy-intensive than traditional approaches, making it economically viable for recovering lithium from low-grade ores, found in micas, which are currently ignored by the mining industry.
Adrian Griffin, Cobre’s managing director, believes the additional recoverable deposits from one site, the Cinovec deposit in the Czech Republic, could alone provide 10 million tons of lithium carbonate equivalent, equal to around 20 percent of all the known reserves until now.
“Micas could eclipse all the other resources currently known,” said Griffin, whose company is currently market testing samples from Cinovec.
So far the process has only been tested at pilot level, with an output of 1 to 3 kilos of lithium per hour. But Cobre, which is listed on the Australian Securities Exchange, is in talks with potential partners to build a pilot plant with industrial components.
The company has signed a memorandum of understanding with European Metals Holdings, an Australian mineral exploration and development business, to exploit the Cinovec reserves.
Griffin believes the process being developed by Cobre could throw open the market for lithium, which is currently controlled by a small number of countries and companies.
“As the process is designed to exploit the most abundant lithium minerals, the lithium micas, implementation of this technology on a production scale may well be a disruptive event that changes lithium production strategies on a global scale,” said Cobre in a press release.
Traditionally, lithium has been processed by roasting ores at high temperature before subjecting them to a leaching process.
The roasting is an energy-intensive activity that means it is only economically viable to process high-grade ores such as spodumene, a lithium-aluminium-inosilicate mineral, or petalite, a lithium-aluminium-phyllosilicate rock.
Even with these ores, which can have a lithium oxide content of up to 6 percent, the process results in a price of $3,000 to $5,000 per ton of pure product. It is uneconomical for recovering reserves with less than 5 percent lithium oxide.
Cobre, however, is touting a hydrometallurgical process that can recover product from micas with a lithium content of between 2 percent and 4.5 percent. “Here’s a very abundant source of lithium that’s not used,” said Griffin.
Cobre’s recovery process involves fine-grinding the mica and digesting it in sulfuric acid at around 90 degrees centigrade. This strips all of the metals, including lithium, out of the mica and leaves them in solution, without the need to roast the ores beforehand.
The reaction creates sulfur dioxide, a toxic gas, but this is fed back into the system to create more acid.
The dissolved minerals, meanwhile, are mostly compounds such as aluminum hydroxide or iron and magnesium sulfates, which can either be sold or released into the environment without causing atmospheric pollution.
The creation of sulfuric acid from sulfur is a highly exothermic reaction, providing enough energy to drive the entire metallurgical process, according to Griffin. “You’ll end up with something that’s got a zero-energy footprint,” he said. “You’ve taken the energy out of the equation.”
Sulfur reagent, imported from Vancouver, Canada as a byproduct of crude oil processing, is likely to represent around 30 percent of Cobre’s operating costs. In addition to producing lithium, the process will isolate other minerals that can also be sold commercially.
They include rubidium, strontium, cesium, gallium and, in particular, potassium or potassium sulfate (potash) for the fertilizer market, which can be sold to cover around 20 percent of the operating cost.
Cobre claims it could eventually process 2 percent lithium-oxide micas with a notional operating cost of $1,800 per ton of carbonate.
This significantly undercuts the price of lithium produced from brine deposits, primarily in South American nations such as Argentina, Bolivia and Chile, which can be as low as $2,000 to $2,500 per ton.
Given that the price of lithium is only a minor factor in battery costs, however, Griffin believes the main benefit of Cobre’s process is in opening up raw material supplies.
“Having got the operating costs down, you find there are deposits of these micas all around the world,” said Griffin. “They are quite abundant. They are simply mined and thrown away. So you can get it as a byproduct with no mining cost.”
As one of the three elements believed to have been produced in the cosmological "big bang," lithium is actually very common in nature: there is an estimated 230 billion tons of it in seawater. But because of its reactivity it never occurs freely.
And the kind of high-ore reserves that have been commercially available so far are relatively scarce. According to Griffin, about one-third of the world’s lithium production comes from South America, led by Chile and Argentina.
In Chile, one of the world’s leading lithium providers, production is tightly controlled by the state and half of exports currently go to China, Griffin said. Australian hard-rock spodumene processing is also said to be controlled by Chinese interests.
China itself accounts for about 12 percent of global demand. “You add all of that up and there’s not much available for the free world,” Griffin said.
“At the moment the world consumes, in lithium metal, about 38,000 tons a year, and you’ve got Elon Musk saying, ‘I want another 38,000 tons.’ He’s got to expand that out of something like 6,000 or 7,000 tons of available capacity. Therein lies the fundamental problem with the market. You can’t go and build a 'gigafactory' and just get supply off the street," he said.
While Griffin is aware of the challenges in scaling up the Cobre process, he notes that most of the steps involved, such as sulfuric acid leaching, are already well established in other industrial sectors.
In nickel lateritic ore processing, for example, sulfuric acid leaching takes place at a temperature of up to 270 degrees centigrade. Sources have confirmed that Cobre could be operating at commercial scale within a year.
And Cobre’s breakthrough comes as the battery industry looks increasingly destined to adopt lithium-ion over competing technologies such as lead-acid.
Apart from material supplies, one of the main criticisms of lithium-ion for energy storage so far has been cost, but Tesla pretty much blew that out of the water in May with its Powerwall announcement.
Calculations show the Powerwall working out at $0.05 per kilowatt-hour over a 5,000-cycle lifespan, which is cheaper than an Imergy vanadium flow battery with a 15-year lifespan at current prices.
Another potential problem for lithium-ion has been safety: despite widespread use in consumer electronics, the chemistry has a bad reputation as a fire hazard, which has restricted its acceptance in areas such as New York state.
Again, Tesla has attempted to confront this head-on with the Powerwall. CEO Elon Musk introduced the battery product saying: “It gives you safety.”
Meanwhile, other companies are tackling another safety aspect of lithium-ion chemistry: the production process. In May, Electrovaya claimed to have saved a lithium-ion manufacturing plant in Germany by introducing nontoxic manufacturing techniques.
This, in turn, is expected to further reduce lithium-ion battery production costs.
Meanwhile, energy storage customers such as major U.S. utilities are drawn to lithium-ion because it is a familiar technology and, critically, it is available from established vendors that can provide reliable long-term maintenance guarantees.
In many cases, utilities are happier to take a gamble on a lithium-ion battery from a big, diversified manufacturer such as Panasonic or Samsung than on a superior product from a small company that could go out of business before the warranty period is up.
As a result, lithium-ion is already a favored choice for short-term energy storage. Other technologies are under consideration for longer-term storage, but they may have a hard time competing as lithium-ion continues to progress down the cost curve.
And such progress seems inevitable as lithium-ion technologies become locked into a virtuous circle whereby customers continue to buy the products and manufacturers gain more funds to invest in further research and development.
“Lithium ion is a very versatile technology,” said Roger Lin, director of product marketing at NEC Energy Solutions, a technology-agnostic energy-storage system developer. “There are still a lot of advances that could happen with lithium-ion technologies."
If Cobre Montana’s process can make it to commercialization, then getting hold of the main material, lithium, will no longer be a problem.