"We know the interest of states, but more support is needed to promote lithium research"

Laura Vera and Walter Torres are researchers at the Center for Research and Development in Advanced Materials and Energy Storage in Jujuy (CIDMEJu). They study sustainable ways to extract lithium and how to develop batteries with greater capacity.

Like many young researchers, Laura Vera and Walter Torres arrived in Jujuy a few years ago to work at the Center for Research and Development in Advanced Materials and Energy Storage in Jujuy (CIDMEJu).

The CIDMEJu, which belongs to Conicet, the National University of Jujuy, and the provincial government, is only six years old. It was created with the goal of studying the lithium chain in one of the epicenters of this mining activity. The founding seed was Victoria Flexer, an Argentine researcher and recognized specialist in electrochemistry, the discipline behind several processes in the lithium chain. Lithium batteries can be a key tool to accelerate the energy transition and thus help curb climate change.

'Currently, there are 20 people working at the center. We are few, considering that we are tackling the entire lithium chain: from sustainable extraction to how to recycle batteries that are no longer useful, through the development of new types of batteries,' Walter acknowledges.

Laura adds, 'We know the interest of states in this issue, but more support is needed to promote lithium research.'

- What are the main sustainability issues associated with the current lithium extraction technique?

Laura: 'The current process is done by evaporation with solar radiation. It's very slow, as it can take between 10 and 24 months. These times don't allow for responding to a change in context, like during the pandemic, or due to an economic crisis. Another problem is that the industry only pays attention to lithium. All the other elements in the brine are considered waste. On average, it's estimated that there are about 100 tons of waste for every ton of lithium carbonate produced. These are small mountains accumulated by the side of the salt flat that, in the presence of rain, seep into the soil and change its properties. But the most well-known problem of this process is the loss of water. If you talk to companies, they will say that the brine is not water because it’s highly saline and cannot be used for drinking or irrigation. The reality is that around 800 m3 of water evaporate per ton of lithium carbonate.'

- How can these sustainability issues be mitigated with the new extraction technologies you are developing?

Laura: 'We are applying a technology that is already used in other industries and solves these three problems. It's applied in the chlor-alkali process to produce chlorine in the industry through water electrolysis. We adapted it to apply it to brines. The goal is to recover lithium, but also the other elements in this brine, such as calcium and magnesium of high purity, which have commercial value. We eliminate the solid waste. At the end of this process, we obtain low-salinity water. Because of its quality, it could easily be used for irrigation, which can be an important resource in these arid areas where salt flats are located. Additionally, the process is faster, taking just a few days, as an electric current is applied to extract these components. For this reason, we don’t use chemical reagents, so we avoid the environmental impact of transporting supplies to these places.'

- What is the connection between your center and the industries in the sector?

Laura: 'Thanks to small national companies, we've managed to take our laboratory knowledge to the pilot scale. We went from working with five liters of brine to processing 100 liters in a pilot plant. We also manage scholarships with the private sector. The support of companies is important. We cannot limit ourselves to academic research. It’s necessary to interact with people in the market, who understand not only the economic part but also the large-scale technical aspects, because there’s a big gap between basic science and what ends up being industry. Interaction with industries is not only essential for funding, but also for obtaining that valuable feedback.'

- What are the challenges in accelerating the implementation of these new technologies at an industrial scale?

Laura: 'This is a technology that is already developed for other industries. Then, there are all the adaptations we make to process brines. Many mining companies are already testing similar technologies. The next step would be to develop a prototype to test it in the Puna, but another problem arises: how do we supply electricity to these systems without generating a carbon footprint equal to or greater than the one generated by the current process? The alternative is to attach photovoltaic solar panels directly to the electrochemical processes to keep it sustainable. However, it's still in development, so the economic costs don't add up yet. In other words, there are still details to refine before it can replace the evaporation techniques currently used.'

- What timeline do you envision for the development of new lithium extraction technologies?

Laura: 'We hope that these technologies will be available in the short term because there is a huge social pressure. There is an urgency to mitigate climate change, which is increasingly present in discussions. But there is also an industrial need to shorten production times. Having production in much less than 24 months would be a huge gain for the company. Additionally, by not using chemical reagents, they would reduce production costs.'

New batteries on the way

- Downstream from lithium extraction, how can batteries be made more sustainable?

Walter: 'A battery consists of two electrodes (a cathode and an anode) between which chemical reactions occur, and these reactions are what store the energy. In the current lithium-ion battery, lithium moves between the two electrodes, but it’s a rather limited process. Its capacity can’t be improved by more than 20%. These batteries are limited for use in electric vehicles. The average range of an electric vehicle is 200 kilometers, which is very little for a country like Argentina. Additionally, these electrodes are only part of the battery, not more than 50% or less. The lithium-ion battery contains an addition of heavy metals, which are highly polluting. What’s being sought is to avoid using these components. We’re also working on other materials to create batteries that have five to seven times more capacity in the same volume and weight as current batteries. This involves another technology: lithium-oxygen or lithium-sulfur batteries.'

- When do you envision these technologies being applied in the industry?

Walter: 'Today, this technology has many inconveniences, but lithium-ion batteries had them too when they were first developed 30 years ago. With the new generation, there are several issues to solve, so it won’t be available within 5 years. Science still needs to refine things, for example, to understand what chemical reactions are occurring and what parasitic reaction causes safety or lifespan issues.'

- What is the lifespan of a battery and how can it be recycled?

Walter: 'The lifespan of batteries is short, even shorter than solar panels, which last 20 years. A battery could last up to 10 years, depending on the technology used. Today, most batteries are discarded. At the institute, we’re studying how to recycle batteries, not just to recover lithium, but also other components. The goal is to disassemble it as an electronic waste.'