Ranges, lithium and more: the next generation of batteries for e-mobility
Maximilian Fichtner is an internationally renowned expert in battery technology. Here is his views on the prospects for next-generation electric car batteries, alternatives to the use of cobalt and the benefits of e-mobility to the climate.
The future of electric mobility is tied to the evolution of batteries, something which determines range and reliability. In the coming years, batteries for electric cars will make great strides in two areas in particular: the storage materials that absorb the energy and battery design.
Professor Maximilian Fichtner is a world-famous expert on battery technology. He teaches solid-state chemistry at the University of Ulm and heads the department for energy storage systems at the KIT (Karlsruhe Institute of Technology). This is his vision of the future.
Graphite, silicon and a new design
A composite of graphite and silicon could soon replace pure graphite in the anode. As silicon has a storage density that is ten times higher than graphite, the energy content of the batteries would therefore increase significantly.
In addition, the new battery design could mean they hold significantly more cells while remaining in the same housing. Currently, the actual storage material in a battery system only accounts for 25 to 30 percent of the total content. The rest is made up of the housing, packaging and additives.
“We will see great progress here. Future battery systems will be designed more efficiently and the share of storage material could almost double. This would increase the energy content and reduce the costs of production,” explains Fichtner.
Solid-state batteries
Solid-state batteries offer the option of replacing the graphite at the negative terminal with metallic lithium, which would increase the range by 30 to 40 percent. This is why the technology is regarded as the Holy Grail of battery research.
“I also see opportunities, but uncertainties remain because solid-state batteries do not yet exist in an industrial form, and costs need to be considered,” adds Fichtner. “Today’s lithium-ion batteries are on a classic, falling cost curve. With the introduction of sustainable cathode materials such as lithium iron phosphate, they have already fallen below the benchmark of 100 dollars per kWh, the limit below which an electric car becomes cheaper than a car with a combustion engine. It is not yet possible to say today whether or how quickly this can be achieved with the solid-state battery.”
Range and charging
In the future, the range of electric vehicles will grow dramatically. “Ranges of well over 500 kilometres will soon be a matter of course- Even a range of 1,000 is possible. Overall, the development of the vehicles is on the right track. On the other hand, I see challenges in providing an appropriate charging infrastructure; we need an extensive network of powerful fast-charging stations,” says Fichtner. He also stresses the importance of enabling city dwellers without their own wallbox to conveniently charge their electric cars.
Another element that needs further work is standardised pricing for the public road network. “The electric car has the best carbon footprint of all drive types in the passenger car sector – we should therefore ensure that e-mobility prevails,” emphasises Fichtner.
Raw materials
Cobalt is currently mainly used in mobile phone and notebook batteries, as well as in hard and cutting steels. “In terms of electric mobility, on the other hand, a complete exit seems to be possible – and necessary. Not only because of the human rights problem, but also because of the limited reserves. A good alternative is lithium iron phosphate, a material that is cost-effective, sustainably available and non-toxic. The so-called manganese spinel could also be an option,” explains Fichtner, before making a final reflection on lithium: “There is not yet a convincing replacement for this material. However, I also see the situation here as not so critical since global lithium reserves are much greater than those of cobalt. And there are currently alternatives to lithium extraction from salt lakes.”
Source: Volkswagen Newsroom