Are Batteries All They’re Charged Up to Be?

by Daniel Huffman

In the midst of Tesla’s rise and the larger electric vehicle market’s recent growth, the automobile industry is beginning to shift away from traditional internal combustion engine vehicles — and for good reason. Transportation accounts for 29% of the United States’ greenhouse gas emissions as of 2017. Electric vehicles provide nearly all the functionality of a gas-powered vehicle, without emitting greenhouse gases during daily use. In an era of dangerous air quality and rampant climate change, electric vehicles are aimed at providing a way for individuals to reduce their own carbon footprints, as well as that of the transportation sector as a whole. Upon deeper inspection, however, things are not so black and white. The technology employed within these vehicles, although cleaner than internal combustion engine vehicles, is marred with environmental and human costs associated with its production. Perhaps the most crucial component of such a vehicle, the battery, carries with it an assortment of environmental repercussions and must be further developed in order to become as clean and efficient as possible.

In most modern electric vehicles, as well as other devices such as smartphones, lithium-ion batteries are the chosen power source. Although lithium is relatively abundant compared to other rare metals required for electric vehicle production, such as neodymium and praseodymium, the processes behind its mining and extraction are often problematic. For one, lithium extraction in South American countries, such as Chile, requires substantial amounts of water. The process of mining lithium in these areas involves the pumping up of brine to the surface followed by a series of filtrations and evaporations to acquire lithium carbonate. In addition to consuming about 500,000 gallons of water per ton of lithium, this process can also contaminate the water supply through the release of toxic chemicals involved in the extraction process. Standard lithium mining from ore has also been shown to damage soil and landscapes, involving the clearing of large swathes of land and the consumption of significant quantities of energy.

Another crucial component of lithium-ion batteries is cobalt, which is a component of the battery’s cathode found predominantly in the Democratic Republic of Congo and central Africa. Like lithium, cobalt has its own drawbacks. Cobalt is toxic even as an ore, thus, mining the metal is often dangerous — especially when protective equipment is not used. Compounding upon this danger is the fact that child labor is often employed in the mining process, adding further ethical concerns to the production of lithium-ion batteries.

Lithium and cobalt are merely two of the many components comprising lithium-ion batteries, and the mining process of the other metals utilized are similarly imperfect. In regards to greenhouse gas emissions, research has shown that the manufacturing process of lithium-ion batteries carries a greater carbon footprint than mining and refining the constituent metals. Currently, the manufacture of lithium-ion batteries in factories relies on a lot of electricity, often generated from nonrenewable sources. One 2017 study by Hao et al. suggested that the production of lithium-ion batteries in China for use in electric vehicles caused the greenhouse emissions associated with the production of such vehicles to be 30% greater than those that result from the production of internal combustion vehicles. 

However, there is room for improvement on this front as battery production has been shown to be more efficient recently, and as industries transition more fully to cleaner sources of energy, the associated carbon emissions will accordingly decrease. Due to the drawbacks of current battery production procedures, scientists and researchers are actively working to optimize the technology we use to store energy. One potential avenue toward cleaner battery technology is devising a more sustainable route of securing the lithium and other materials utilized in battery production. For instance, scientists theorize that lithium could be harvested from seawater through cleaner means. However, the mechanical extraction process would likely expend significantly more energy. Alternatively, some researchers are trying to develop new batteries that replace lithium and cobalt for safer and more readily available substances without compromising on energy density or cost. To accomplish this, some scientists are looking to incorporate nanomaterials, substances between 1 and 100 nanometers in length, into battery technology. Since these types of materials have a far greater surface area per mass ratio than traditional battery components, they can store a larger number of ions and electrons and hence more energy. Additionally, the multitude of nanomaterials that would be present in such a theoretical battery would allow for ions and electrons to travel much faster, rather than having to channel through fewer but larger particles as they travel between electrodes. 

Environmental concerns in regards to lithium-ion batteries continue until the end of their lifecycle, with only a small proportion of these batteries being recycled. As a result, some researchers are searching for more sustainable methods of disposing of these batteries, including potentially using bacteria to safely process the volatile materials found within the lithium-ion battery. While these are just a few examples, it is clear that scientists are concerned with the compromises associated with current batteries and are committed to further improving their efficiency and sustainability.

Despite these environmental costs involved in production, electric vehicles still possess a smaller carbon footprint over their lifetime, compared to standard vehicles, due to the lower emissions associated with their daily use. Consequently, electric vehicles, whether they are personal automobiles or public forms of transportation, will likely have a role in a cleaner future post-fossil fuels. Anticipating this, scientists and engineers continue to research and develop cleaner, more sustainable methods of producing the battery technology required for these vehicles. At the same time, the general public can play a role in reducing their own battery-induced environmental footprint by opting, when possible, for non-polluting means of transport, such as walking or biking, or more public forms of transportation, which spread the environmental costs among a greater number of individuals. Through these actions, society can pave a way forward for cleaner transportation and a carbon-free future that is humane and sustainable.