Electric vehicles accounted for 10% of vehicle sales worldwide in 2022. By 2030, they will likely account for 30%. Sometime before 2040, electric cars will outsell gas cars. We’re going to need a lot more electric car batteries, but they present some issues.
The European Union and some states in the US have enacted laws that ban the sale of new gasoline-powered cars starting in 2035. While electric vehicles don’t emit greenhouse gases, they are not free from their own environmental concerns. We need to be planning now how to minimize them.
Making batteries requires mining and processing metals. Mining always has a bad environmental impact. Both mining and processing also have social and geopolitical implications that we must keep in mind. The typical American attitude that bigger is better can only aggravate these problems.
Basic facts about electric car batteries
Batteries in general comprise a negative pole (anode) and a positive pole (cathode) separated by an electrolyte. During use, current flows from the anode through the electrolyte to the cathode. Recharging a battery reverses the flow.
Most lithium-ion car batteries use a liquid electrolyte, a graphite anode and a metal cathode. Excluding steel and aluminum, electric vehicles require six times as much mineral content by weight as gasoline vehicles. The issues with electric cars chiefly concern the batteries. These minerals are not renewable resources. Mining and processing them cause harm to the environment and the health of people who work with them.
One of the most common versions of lithium-ion car batteries uses a nickel/manganese/cobalt cathode. Five metals account for nearly half their weight:
- Lithium (3.2%)
- Cobalt (4.3%)
- Manganese (5.4%)
- Nickel (15.7%)
- Aluminum (18.9%)
The aluminum in the battery is in addition to the aluminum in the car’s frame and body.
Environmental and geopolitical electric car battery issues
Poor countries have some of the most productive mines and the largest proven reserves of some of these metals. They have no monopoly. China and Australia, for example, are leading sources of lithium. But poor countries can’t adequately regulate the mines, which often exploit workers, pollute the environment, and endanger the health and livelihood of the nearby population.
Wherever metals come from, China controls nearly all of the processing infrastructure for manganese and more than half for all the other metals except nickel.
Sales of electric vehicles are expected to surpass sales of gasoline and diesel vehicles by 2040. Manufacturers achieve greater range by supplying vehicles with larger batteries. And let us not forget that the energy storage batteries now used to make wind and solar energy viable depend on the same metals. Cell phones and other electronic gadgets also run on lithium-ion batteries.
Meeting increased demand will require more land devoted to mining, land that most likely will displace agricultural land or forests. Geopolitical and diplomatic consequences are more difficult to predict, but China is no friend of Western nations, where demand for batteries is so strong.
Is it possible to recycle lithium-ion batteries? Sort of. As with nearly everything else, technology for recycling and participation rates lag behind manufacturing and sales. So far, electric car battery recycling is hardly economically viable, although research continues to explore solutions.
Alternatives to today’s batteries
Manufacturers have made strides in finding alternatives to the standard lithium-ion car batteries. They are also looking for ways to improve lithium-ion batteries, mostly by exploring alternatives to the nickel/manganese/cobalt cathode. The lithium iron phosphate battery looks promising. Using something else besides graphite for the anode could reduce weight, increase energy density, and make charging faster. So far, silicon anodes have not worked adequately, but Mercedes-Benz hopes to start using them in 2025.
Some companies are working on sodium-ion batteries. Lithium (atomic weight 3) is the lightest of all solid elements. Sodium (atomic weight 11) is the third lightest. Although heavier, sodium has the advantage of being less expensive and easier to work with. So far, it is not clear that sodium-ion batteries can compete with lithium-ion for range and charging time in car batteries. They can more likely displace lithium for grid-storage batteries, which would at least keep lithium prices from rising as fast.
Solid-state batteries replace the liquid electrolyte with ceramics or other solids. Michael Farraday invented them in the 1830s, but until recently, no one figured out how to make them work well enough to be practical. Quantumscape, which went public in 2020, has promised to supply Volkswagen with solid-state car batteries by 2025.
The need for restraint
Issues with electric car batteries include their size. How big is big enough and how can we keep from squandering resources?
The average American driver drives only 37 miles a day. Anyone who lives in a single-family dwelling can recharge an electric car overnight in their own garage. Manufacturers are promising electric cars with a range of hundreds of miles. To do so will require very large batteries, which, in turn, will require a lot of the various metals. Most of the time, drivers won’t need nearly that much capacity.
Small batteries that can be recharged quickly without major power usage are more practical and better for the environment.
Of course, the average American driver probably plans to make longer road trips from time to time. These trips will probably comprise less than 5% of their annual milage. For these trips, and only for these trips, they will need larger batteries than normal. Are any automotive designers even thinking about this issue?
The obsession with EV range is all wrong / Shannon Osaka, Washington Post. July 7, 2023
The underbelly of electric vehicles / Aaron Steckelberg et al., Washington Post. April 27, 2023
What’s next for batteries / Casey Crownhart, MIT Technology Review. January 4, 2023