An important warning to the spread of electric vehicles is the question of what are we going to do with all these car batteries once their time is up. There are also concerns about the environmental impact of lithium mining, not to mention other essential metals such as cobalt and nickel. Let’s take some time to see what happens to electric vehicle batteries, where they go when they’re dead, and whether electric vehicles are still the best option for the environment in the end.
EV batteries are highly recyclable. More than 95% of the components of a lithium-ion battery can be extracted through hydrometallurgy. This involves grinding up the battery components and running them through an acid solution. A number of solvents and electroplating rounds are capable of extracting individual elements from solution. Melt recovery is common, but is more energy consuming and less effective. Pollution caused by this recycling process is insignificant. The problem right now is that we don’t have enough recycling facilities currently operating on the scale needed to meet the deluge of electric vehicle batteries coming out of their end of life. We are currently only recycling about 5% of our lithium ion batteriesbut fortunately the rising value of lithium, cobalt and nickel makes the prospect of recovering it much more attractive.
Making the recycling process profitable can be challenging, depending on the materials you’re targeting, but this study breaks down the economics quite well.
“Most process routes achieve high yields for the valuable metals cobalt, copper and nickel. In comparison, lithium is only recovered in few processes and with a lower yield, although of high economic value. Recovery of the low-value components graphite, manganese and electrolyte solvents is technically feasible but economically challenging.”
Although it is a vital component of batteries, lithium only accounts for about 11% of the total mass of a cell. You can see how it influences battery chemistry here. Australia, Chile and China produce most of the world’s supply of lithium. automotive applications consume about 31% of that supplybut demand is expected to continue a strong upward trajectory.
There are two ways to extract lithium: salt flats and hard rock mining. When hard spodumene ore is mined, it is broken down, separated, subjected to an acid bath, and eventually lithium sulfate can be extracted from the mixture. This is a very traditional mining method with all the usual risks of contaminant build-up in tailings ponds. It is a relatively cheap process compared to salt processing, but it also produces a lower quality product. Australia, with a whopping 46% of global lithium production, relies heavily on hard rock mining. Since this method is so labor intensive, it is not surprising that it produces approximately triple the emissions per metric ton of lithium, compared to salt flats.
Salt flats are created when water is pumped underground and returns to the surface with dissolved minerals. This brine spreads through wide pools to evaporate, leaving behind minerals to be separated and processed. Salt pans are common in a triangle that overlaps Chile, Argentina, and Bolivia. The nearby Andes Mountains have created large deposits not far below the surface thanks to geothermal activity that seeps minerals from the volcanic rock. Higher elevation also promotes faster evaporation in brine pools.
The main cost of lithium extraction in the salt flats is the use of water. However, getting exact numbers is a challenge. Estimates range from 250 gallons of water per pound of lithiumuntil a million gallons. Data from the Chilean government suggest that brine production in the Atacama flats is exceeding the capacity of the aquifer to recharge by approximately 30%. About 65% of the region’s water is used for lithium mining. These operations are being carried out in deserts where water supply is already tenuous for local populations and exercises additional pressure on local agriculture. In addition to dealing with increasingly scarce water in the driest places on Earth, Aboriginal groups living in neighboring areas are also at risk of dealing with abandoned materials Y disturbed ecosystems due to the mining industry. Many have already been subjected to this type of abuse by international mining companies in the past. As a result, they have either strongly opposed new projects or claimed significant ownership of them.
Batteries have a bunch of other materials in them, like nickel, cobalt, and graphite.
Cobalt is mainly mined from the Congo, which produces about half of the world’s supply. Heavy Chinese investment has resulted in many industrial mining operations being built to meet their production demands, but local workers are often excluded from this enterprise. Instead, they are relegated to dig their own artisanal mines with few safety precautions and few resources in case of injuries. They end up selling their cobalt to the same traders that transport industrially mined cobalt to refineries in China.
Nickel production is less tense, but not without its costs. It is widely mined throughout the world, with Indonesia delivering around 30% of total supply. Most of it goes to the manufacture of stainless steel, and only 6% goes to batteries.
Are electric vehicles still better for the environment once you account for battery production and recycling?
Collectively, that might seem like a high cost to make our electric vehicles a reality. Life cycle assessments comparing electric cars to traditional ones show that electric vehicles are burdened with emissions thanks to the cost of batteries. Where that difference is compensated is throughout the useful life of the vehicle. internal combustion engines make cars 60% to 68% more emissive than electric vehicles in the United States. Considering the outsized role that fuel plays in this calculation, cleaning up the power grid is almost as important as putting a bunch of electric vehicles on the road. The average emission savings in Europe can range between 28% and 72% depending on how electric vehicles are charged.
Ultimately, electric vehicles remain a necessary transition to make a dent in global emissions. With that said, those who live near the mines still have their fair share of challenges stacked up against them. They face the ugly environmental effects of mining long before those of climate change. Governments will have to do a better job of holding the mining industry to account for proper site management before we get too cocky about populating a green future filled with electric vehicles.