Product story

Going the extra mile: how Graphite and Carbon black make electric cars go the distance

Environmental regulation might be driving the trend for increased manufacturing of electric cars, but high-quality ingredients in their batteries are ensuring drivers reach their destinations safely and reliably.

Electric car being charged

When the EU Commission unveiled its mobility strategy in December 2020, its ambition to get 30 million electric cars on European roads within 10 years served as a good indication of the continuing rapid growth of plug-in vehicles.

The earliest electric motor documented was in the late 1820s, and rechargeable batteries for automobiles first appeared in 1859 – but it’s only in the past decade that sales have really accelerated, from around 12,5001 electric cars globally in 2010 to more than 10 million2 today.

Some projections put the worldwide number of electric vehicles by 2030 at 200 million. 

Electric cars help reduce our carbon footprint

Research suggests that, across its entire lifecycle, an electric car has less impact on climate change than gasoline cars, producing fewer direct emissions. Tough regulations to reduce the carbon footprint of the transport sector will mean a significant gear change for manufacturers of lithium-ion batteries – and it’s the high quality of minerals and other ingredients in these batteries that are making electric vehicles a more attractive proposition.

The key role of carbon black & graphite in lithium-ion batteries

Minerals do not produce energy, but they enable all other active components in the battery to do just that. 

Marcello Coluccia, Imerys’ Application Director for Lithium-ion and Conductive Polymers, refers to carbon black and graphite, which Imerys produces in Belgium and Switzerland respectively, as the “salt and pepper in the main dish”. 

Added in tiny amounts – less than 1% of the total raw materials – they are critical to supporting an electronically conductive path.

On the positive side of the battery (the cathode) are metal oxides, and the graphite is on the negative side (the anode). It is compulsory to use carbon black or graphite on the cathode, but it is not always necessary on the anode.

“Without it, you would have materials that have the potential to deliver a lot of energy, but their electrons wouldn’t be able to find the way to those particles,” Marcello explains. “Carbon black exploits that energy within the battery by building a network – an electrically conductive path – for the electrons to reach the metal oxide particles.”

The higher-performing the additive in enabling electrical conductivity, the fewer battery-makers need to use.  

How does electric car battery technology meet drivers’ needs?

Ten years ago, people were concerned about the battery capacity.

“Typical battery performance meant the distance that could be travelled on one charge was limited,” says Marcello. “People had a fear of being stranded – it’s called range anxiety. Also, there were safety incidents related to the battery. If people are worried a car might catch fire, they are not going to buy it.”

So what are drivers looking for in an electric car?

Improved driving range

Today’s lithium-ion batteries take you further – around 400 kilometres on one charge. That’s about four times the distance of early electric vehicles. The range is a consequence of energy density – achieved either by bigger batteries or higher-performing elements within them.

A quick-charging car

If your battery is running low, you don’t want to have to plug it in at a public service station for several hours to charge it sufficiently to get you to your destination. The design and raw materials – including minerals – play a critical role in the development of electric car batteries capable of charging to around 80% in 20 minutes.

 A safe vehicle

Accidents relating to batteries catching fire have been well-publicized. With the number of electric vehicles on the road growing rapidly, their reputation as a credible mode of transport relies on the number of safety incidents not increasing.

“Safety relies on the combination and cleanliness of ingredients in the battery management system”, insists Marcello. “In pushing the performance of a battery, you can’t compromise the quality of raw materials and, therefore, safety aspects.“ 

The purity of carbon black and graphite is essential to give the optimum safety performance. We are talking about impurity levels on a scale of parts per billion. Every contaminant has the potential to cause a circuit failure and kill the battery.

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Imerys site in Bodio (Switzerland)
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Imerys site in Willebroek, Belgium

Continuous improvement in green technology

Electric vehicles have made tremendous improvements in a relatively short time, but, like most green technologies, are not at the point where they have a lower CO2 output than the alternatives.

“In the long-term, electric cars will be better for the environment,” concludes Marcello. Imerys is committed to developing sustainable technologies, including lithium-ion batteries, that reduce CO2 emissions and dependency on fossil fuels.

“It’s been a long journey of innovation for the electric car – nearly 200 years – but we are just at the start of what these vehicles can achieve.”

 

1 This is an estimated figure for the end of 2020. Source: https://singularityhub.com/2019/04/29/electric-cars-are-estimated-to-be-cheaper-than-regular-cars-by-2022/

2 This is an estimated figure for the end of 2020. Source:  https://www.ev-volumes.com