Batteries are a defining component of electrified vehicles and will need to halve in cost and double in energy density in the next two decades without using unsustainable materials or manufacturing processes, says Dave Greenwood— professor of advanced propulsion of the Warwick Manufacturing Group.
And in the long term, it can’t be done without outside industry input, the academic said.
In a wide-ranging report covering all aspects of future vehicle development, the Automotive Council of the UK’s ‘Roadmap report’ looks into all technologies that will be needed for vehicles for the mid-century.
The short-term focus centres on optimising existing lithium-ion cells and pack technologies to meet the imminent demand for electrified vehicles. The challenges listed in the short term are largely manufacturing ones, with incremental technical innovations such as fine-tuning the chemical composition of anodes and cathodes as well as managing the health of battery packs.
As time progresses, and the potential pathways for satisfying future performance requirements diverge, more profound technical and manufacturing challenges arise, Greenwood said.
Perhaps the most important long term change is that future improvements in battery packs will shift from improving in-use performance to the total life cycle impact of battery manufacturing. This will not only drive the automotive industry to scale-up recycling facilities but also ensure the chemicals used in batteries are sustainably sourced and manufactured.
Greenwood said: “What’s clear is that for the automotive industry to address these battery challenges, we need help from adjacent industries. We hope that these research and development challenges will help facilitate discussions between interested companies and aid those organisations in other sectors wishing to navigate the automotive battery landscape.”
Existing lithium-ion batteries* are likely to dominate the market throughout the current vehicle cycle and the next. In order to reach the challenging roadmap targets set for 2035, better cell chemistry, battery management and manufacturing processes will have to be developed and commercialised to improve energy density, power density and cost.
Whether the cells are traditional lithium-ion or next-generation chemistries, they need to be assembled into modules and packs to make them usable for original OEMs, so pack-level innovations are equally important for the industry to progress. Manufacturers will also need to develop packs that can accept the higher charging rates being developed, without considerably degrading pack performance.
One of the biggest long term challenges in establishing a sustainable battery supply chain is minimising the life cycle impact of battery manufacturing. A key risk identified in the roadmap is the current absence of a sustainable, high-volume solution for end-of-life recycling.
*The importance of both capacitors and batteries is recognised when considering electrical energy storage for automotive propulsion. The roadmap focuses mainly on energy storage devices, as these are initially required to provide zero-emissions capability, potentially supported by capacitors under transient driving conditions.