The future of EV batteries
Last year, two British start-ups AMTE and Britishvolt announced plans to build the UK’s first large-scale EV battery factory, investing £4bn and focusing on lithium-ion battery production.
It’s clear why lithium-ion is the top choice for electric car usage – it’s efficient and charges at a fast rate. But there are many downsides – socially and economically. For example, lithium-ion battery production can result in toxic chemical leaks capable of destroying wildlife habitats.
As a result, there are trials taking place across the industry to find a better long-term solution.
One positive development with lithium-ion in recent years however is that costs have reduced. Back in 2015 the battery accounted for 50% of the cost of an electric vehicle, in 2019 it was around 33% of the cost, and looking at the cost today in comparison to 2010, the price of an average lithium-ion battery pack has dropped by over 80%.
Removing Cobalt from lithium-ion batteries
A large societal issue with current lithium-ion batteries is the amount of Cobalt, a rare earth metal, used in their production – the majority of which is sourced from the Democratic Republic of Congo where it’s often mined by children in unregulated conditions. Manufacturers are now committing to reducing the use of Cobalt in the production process – or in Tesla’s case, removing it completely.
Researchers at the University of Texas are working on developing an EV battery that uses a high percentage of nickel (paired with manganese and aluminium) instead of Cobalt for the cathode.
Additionally, SVOLT, a company based in China, has confirmed the development of Cobalt free batteries for the EV market, claiming that they have a higher energy density, and could help EV ranges get up to 800km (500 miles), while also increasing the life and safety of the battery.
Silicon anode may replace carbon within lithium-ion batteries
The hope is that silicon will gradually replace carbon as the anode material in lithium-ion batteries, as its capacity is ten times higher. However, silicon is currently facing big challenges due to its unstable material properties. Researchers at University of Eastern Finland have developed a method to produce a hybrid anode, using mesoporous silicon microparticles and carbon nanotubes – where the material is sustainably produced from barley husk ash.
The development of solid-state batteries
US-based EV battery start-up QuantumScape has been making waves with their exploration of a solid-state automotive battery, which would remove a lot of the environmental dangers with existing lithium-ion batteries, and even make them lighter, cheaper and more efficient and enable a charge to 80% in less than 15 minutes.
Lithium-sulphur batteries are a way away yet – perhaps 2030 at the earliest, but the benefits could be great – they aren’t toxic, are 100% recyclable, cheap, and sulphur will replace the nickel, cobalt and manganese, saving up to 50% of the weight. Sony is said to have been working on it for years, with off-road vehicles and aeronautical applications likely to take advantage of these batteries first.
Lithium-sulphur also produces 40-50% more range, due to energy density.
Ultra-fast Carbon electrode
NAWA Technologies has created an ‘Ultra Fast Carbon Electrode’ and intends to put it to use for electric vehicles by 2023. It is said to boost battery power ten-fold, increase energy storage by a factor of three and increase the lifecycle of a battery five times. NAWA believes a 1000km range could become standard, with charging times cut to 5 minutes to get to an 80% charge.
In the more distant future (perhaps up to 15 years from now) we may see the arisal of a compostable, organic lithium-oxygen battery. This ‘organic’ battery is described as graphene-based with a water-based electrolyte and said to be dense and capable of very fast charging.
Use of Sodium-ion
Sodium-ion was developed at the same time as lithium-ion, and is coming back as a consideration for EVs as lithium prices are so high. It has slightly better extreme temperature performance.
CATL, a Chinese battery manufacturer which provides batteries to many car makers recently announced a new generation of sodium-ion batteries, with plans to improve energy density to about 200-Watt hours per kilogram, which is at least competitive with lithium-ion.
A step closer to extreme fast-charging – asymmetric temperature modulation
Research has been able to demonstrate a charging method that may make XFC – extreme fast charging a reality – delivering around 200 miles of range in 10 minutes with 400kW.
Electric will soon be able to take you further
We already have many models claiming to offer a range of 250+ miles. And attempts to push the boundaries are already in progress, with Tesla looking to offer a range of 620 miles with their upcoming Roadster 2.
Wireless & self-charging technology development
If Light Year One is anything to go by, we may start seeing more EVs with solar panel features, to allow for off-grid self-charging – which could further decrease costs.
Wireless charging infrastructure is also under exploration – involving charging ‘pads’ positioned underground – allowing for wireless charge-ups while parked. Trials have already begun, with the Department of Transport having installed wireless ‘pads’ in taxi ranks in Nottingham.