Cobalt is an essential component for electric vehicle batteries; we delve into that
There is a degree of familiarity with the materials cars are made of: although most of us don’t think much of steel, aluminium, glass and plastic, we generally know what they are and where they come from. The same goes for the gasoline and diesel that have fueled vehicles for the last century or so.
Electric cars are somewhat of a different proposition, as their batteries are made from materials that may not be so familiar. These include lithium, manganese, and nickel, as well as cobalt, an element that has been the subject of a great deal of media scrutiny in recent years.
Here, we delve into what cobalt is, why it’s used in electric vehicle batteries, and why there’s been some controversy surrounding it.
What is cobalt?
Cobalt is a metallic element (symbol Co) that is found in the earth’s crust, although not always alone: in most cases it is a by-product of the extraction of nickel and copper.
Used for millennia as a dye for glass and ceramics (hence cobalt blue), cobalt has been used more recently to create alloys from which jet engine turbine blades are built, and more recently , even in lithium ion batteries. These are commonly found in smartphones and laptops, and now power nearly every electric car in the world.
Why do EV batteries need cobalt?
Lithium-ion batteries provide the electricity that powers an electric car’s motor when lithium ions move from the battery’s negatively charged anode to its positive cathode.
Cobalt comes into play because it is very energy dense, meaning it can handle a lot of electricity relative to the amount used, and because it has excellent heat resistance properties, which is important from a safety perspective. It is for these reasons that lithium-ion battery cathodes are made up of approximately 10-30% cobalt, with each EV requiring 6-12kg of the element.
Why is cobalt controversial?
It all has to do with where it comes from and where it goes before it reaches the batteries. Around 60% of the world’s cobalt is found in the Democratic Republic of the Congo, where unregulated ‘artisanal’ mines (some of which employ child labourers) produce between 20 and 40% of the country’s cobalt.
Cobalt cannot be put directly into a battery once it has been mined from the ground, however it must first be processed into a refined form. About 80% of the world’s cobalt is processed in China, which some consider a suboptimal geopolitical arrangement.
What are automakers doing about it?
A 2018 survey of automakers found a general awareness of cobalt-related issues, with corporate social responsibility programs aimed at reducing or eliminating the use of what some companies call “conflict materials.”
Will EV batteries always need cobalt?
There has also been a concerted effort to reduce the amount of cobalt used in lithium-ion batteries, with many manufacturers switching to 8:1:1 chemistries, which use one part cobalt and one part manganese for every eight parts of lithium. This is half the amount found in older 6:2:2 chemistries, which use two parts of cobalt. Research is also underway to produce batteries that do not require cobalt, although this technology appears to be some way off.
However, it is worth noting that while cobalt is not the only problematic element used in the manufacture of batteries for electric vehicles (about half a million tons of water is required to produce a ton of lithium, for example), oil production is far from exempt. problem, either: The gasoline and diesel our cars run on are linked to oil spills and other environmental problems, while oil refineries are a major contributor to greenhouse gas emissions.