Electric Vehicle (EV) battery prices have fallen dramatically and will continue to fall as engineers and scientists focus on design improvements and innovation. We hear much in the press about Cobalt and Lithium, less about Nickel and Copper, (Copper being a little trickier to obtain at the moment) but combinations of these are typically critical to battery manufacture.
It’s not just the battery itself but supporting technologies which are critical. Liquid cooling protects the batteries and helps with heating and cooling. Heat exchangers help extend range. Clever packaging and manufacture of the batteries also have their part to play to improve performance and reduce costs.
However there are some issues commonly raised about EV batteries around mining, re-use and recycling. I look at each in turn.
The oil industry is a dirty business, with many cited catastrophes and alleged human rights abuses. However the battery industry is also under the spotlight as it requires very large quantities of specific materials (mainly lithium and cobalt) which are mined in conditions which endanger the environment and human rights.
According to the US Geological Survey (USGS) the worldwide resources of lithium are some 80 million tons. The top four producers, Australia, Chile, China and Argentina have some 14 million tons in reserve. USGS estimates US deposits to be 6.8 million tons and British Geological Survey (BGS) found there are extensive deposits in UK but how much is commercially mineable is unknown.
The extraction process is mainly pumping brine from mixed salt deposits and evaporating for months before separating out the lithium using toxic chemicals like hydrochloric acid. This uses 500,000 gallons of water to produce a ton of lithium. Water use and environmental impact can be reduced by using the Direct Lithium Extraction (DLE) method but this is costlier and takes longer. A promising development being pioneered in California and Cornwall is geothermal lithium extraction which also creates geothermal power.
Two thirds of cobalt production comes from the Democratic Republic of Congo (DRC), the majority produced by large open cast mines. A recent BBC documentary highlighted two separate issues: mining companies workers were not paid well and worked in poor conditions; unofficial artisanal workers had even worse conditions but relied on the meagre income. One report showed that artisanal mining accounted for 30% of production. In 2019 a new government in the DRC created a group to help organize and improve the operation of artisanal miners so that they can support and feed their families but have reduced risks. However even today many people are killed and injured.
One solution is changing chemistry to use less or even no cobalt although this would impact the livelihoods of many in the DRC. Some EVs including Tesla already use a cobalt free battery. Another solution is public pressure to improve the conditions of cobalt miners.
Re-use of batteries
An EV battery is deemed at the end of its life at about 70% of the original charge capacity. Some owners continue to use their EV beyond this limit. Either way the vehicle will have done a considerable number of miles by then. However 70% of a big battery is still a lot of power. Some companies are already using batteries removed from crashed or worn out vehicles in battery storage facilities and at grid scale. This is an important part of the future of a green economy and extremely cost effective as the carbon footprint is ‘already spent’. Used EV batteries are also targeted to be used for powering homes (power walls) rather than using new batteries used today. There is also a thriving cottage industry of people who make power walls from used batteries from EVs and other sources.
If an EV battery is not re-usable then recycling can mitigate the environmental impact. The large majority of materials in a battery can be recycled and it can be profitable if at scale. There are several UK companies that specialize in metals recovery, working to be ready for when there is enough volume of batteries at end of life.
Over time recycling will help limit the level of mined product so is a vital part of the future of the battery industry overall. Adding EV batteries to the volume of recycling will make the recycling of batteries from tablets, computers, mobile phone and toys (which currently have erratic and low volumes) more viable.
But there are many ways to recycle, this industry is still developing and some challenges to overcome. Graphite in batteries is one area where the quality is too low to reuse after recycling in a standard battery. There are many challenges to recycling. Recycling plants will be needed around the world and as yet we are a long way from that. One manufacturer, MG, is working to address this and has been piloting recycling in India, although not at any scale.
Many of the negative claims against the EV and battery industries are valid. However it is also a rapidly changing landscape with the commercial drivers helping stimulate solutions to the sourcing, re-use and recycling of materials. The carbon footprint and environmental benefits of the EV are now generally accepted as being significant but the recyclability of the EV battery may end up being one of its strengths as technology is rapidly advancing.
Whilst outside the scope of this article, more radical solutions also being researched. Some are not necessarily going to win but some will. Aluminum air batteries are one intriguing development as are Iron Air batteries for infrastructure storage (grid, charge points etc.).