Electric vehicles have skyrocketed in popularity over the last few years thanks to Tesla ushering in EVs en masse and legacy automakers like Ford, Volkswagen and BMW fully embracing the new technology. EVs are often seen as a more eco-friendly and alternative to gas-powered cars, and they often appeal to those with a more environmentally conscious mindset. That said, EVs come with their own environmental drawbacks. We're going to detail what some of those drawbacks are and their impact on the environment.
The current state of electric car battery production is rife with ethical quandaries — specifically related to materials sourcing and pollution. Lithium, cobalt, nickel, and a number of other rare earth metals must be mined, processed and refined and then turned into an electric car battery. The process is energy-intensive and is often referred to as an EV's "indirect emissions," so named because they don't come from using the car on a day-to-day basis, but the processes employed to manufacture it.
The negative impact of battery production starts before their materials even come out of the ground. Almost 60% of the world's lithium is sourced from South America — the so-called Lithium Triangle covers parts of Argentina, Bolivia and Chile — in arid areas where water is scarce. Lithium mining uses significant amounts of water, with Euronews estimating that nearly 600,000 gallons are needed to produce one ton of lithium. This demand diverts water resources away from nearby communities, and the toxic chemicals needed to produce lithium can pollute both the air and local water supply.
While an exact understanding of how lithium-ion batteries are made isn't necessary, it is important to know how the process results in pollution. Lithium, cobalt, nickel and other rare earth metals are extracted from the ground and refined into the cathode of the battery, while the anode is usually made from a form of carbon. (Anodes and cathodes are the negative and positive parts of the battery, respectively.) The cathode and anode each start as a slurry of their raw components, which is then dried, turned into a thin film, and coated with a foil that is baked onto their surfaces. The film is then either wound or stacked depending on the ultimate cell shape of the battery. This process forms the basis for a lithium-ion battery.
As you might expect, carbon dioxide and other pollutants, if applicable, are emitted at various stages of this process. According to the Massachusetts Institute of Technology, the carbon dioxide emitted from the production of an 80-kilowatt-hour (kWh) battery in something like a Tesla Model 3 would range anywhere from roughly 2.5 tons to just over 17.5 tons. MIT also notes that for every metric ton of lithium mined, as much as 15 tons of carbon dioxide are emitted into the atmosphere. It's possible that these numbers will come down as companies that produce batteries refine their processes, but for now it remains a relatively dirty operation.
Battery disposal and recycling
As with your laptop, phone or any other mobile device, the battery in an EV won't last forever. Though the viable lifespan of an EV battery can be 10 years — and potentially more depending on how frequently it's used and a user's charging habits — eventually these batteries will need to be disposed of. But battery disposal, if done improperly, does present some environmental hazards.
Damaged batteries can also pose a significant fire risk. When a battery reaches a critically high temperature or the pack is punctured, certain chemical reactions can occur inside the battery, eventually resulting in a short circuit. Once this happens, the battery begins generating more heat than it can shed, in a process called thermal runaway. Essentially, the battery acts as both its own fuel and oxygen source, meaning the fire can burn until the fuel source is completely used.
Burning batteries release carbon monoxide and hydrogen cyanide among other toxic fumes. The burning batteries release hydrogen fluoride, a toxic gas that, if inhaled by humans, results in bone loss and other health defects. Dealing with a battery that has caught fire is one of the main challenges when it comes to their safe disposal, and it's what makes recycling them an important part of their life cycle.
Battery recycling has its own drawbacks. Batteries are typically recycled via one of two processes: pyrometallurgy and hydrometallurgy. While they are better solutions than simply letting used batteries decompose over time, both processes come with environmental drawbacks. Both pyro- and hydrometallurgy produce waste and emit greenhouse gases. There's also direct recycling, where batteries are discharged and physically disassembled. While more of the battery material can be used and recycled with direct recycling, and there are far less emissions with this method, there have been challenges deploying it on a commercial scale.
It's important to properly dispose of batteries, and the processes can become more ecologically friendly over time. But there's also an opportunity now for automakers and battery recycling companies to come up with new, more efficient and environmentally conscious ways of giving batteries a second life.
Electricity generation and infrastructure
While electric cars can charge using electricity generated by clean, renewable sources, the reality is that the U.S. grid still generates the majority of its electricity from the burning of fossil fuels — primarily, natural gas and coal. While this is certainly a concern, this is where we have to compare electric vehicles to gas cars to get a better idea of their true environmental impact.
According to the U.S. Department of Energy, on average, a gas-powered car will emit 12,594 pounds of carbon dioxide from its tailpipe every year. When accounting how an EV gets the energy it uses to charge up (whether that be from natural gas sources, hydroelectric sources, coal burning or other methods), the average EV emits 2,817 pounds of carbon dioxide each year. But in states like California where a cleaner mix of energy sources is available, EVs only emit 1,473 pounds of carbon dioxide per year. In some states like Washington, which uses hydroelectric power for most of its grid, yearly emissions for EVs plummet to just 705 pounds per year.
In this sense, the damage EVs do to the environment is minimal, especially when compared to vehicles with an internal combustion engine (ICE). Yes, there is some impact that EVs have because of where they get their electricity. But their emissions are several magnitudes lower than an ICE vehicle.
The manufacturing of anything new, be it a phone, laptop or electric vehicle, will always come with some sort of environmental cost. Until manufacturing processes become greener and more eco-conscious (across all industries), it's almost unavoidable. Electric cars come with their own drawbacks, but we know that automakers are taking control of their supply chains in an attempt to make them greener and companies are working on new ways to recycle EV batteries. We are still at the relative nascence of the electric car, and things will certainly improve over time.