Battery expert Eckhard Karden said car makers are considering new platform architectures for battery electric vehicles (BEVs) that may eliminate 12V lead batteries.
In a briefing note for BEST, Karden – who until last October worked for auto maker Ford’s engineering and research division in Germany – notes current automotive battery production makes up about half the global lead-battery GWh production capacity.
He is now working as a battery consultant, including for the Consortium for Battery Innovation (CBI).
Legacy OEMs as well as Chinese startups use the established 12V power supply architecture in their BEVs, he said. “Like conventional cars, these vehicles have a 12V battery – often smaller than classic starter batteries, and very often lead batteries.”
Besides their low cost ($40-70/kWh), he said lead batteries are enormously robust even under extreme environmental or abuse conditions.
“This is a huge advantage, particularly if you require emergency supply for safety-critical loads out of this battery,” he said, with steer-by-wire and autonomous driving as examples.
He said Tesla and Rivian, by contrast, have recently announced 48V zonal architectures for their future platforms – of which only Tesla’s low-volume Cybertruck is already in production.
Karden said it is currently undecided whether the mainstream car industry worldwide (not just premium brands) will flip toward zonal architectures in the next 3-5 years too – and whether that then might eliminate many 12V batteries.
“Such architectures are an option for battery electric-only platforms, not for mixed platforms, where part of the production volume still has engines, starters, ignitions and all that stuff,” he said.
For markets still committed to internal combustion engine vehicles, such as India and Brazil, large volumes of lead batteries will be required for a long time to come anyway, he said.
As for mainstream BEVs, Karden said: “Let the OEM architecture teams do their job, but not stop our work. If they decide to keep 12V batteries, particularly for the cost-sensitive volume market, we need appropriate off-the-shelf products ready, and to support their system integration.”
If sized or managed improperly, 12V lead batteries have sometimes caused warranty issues, he noted. “But a few engineering rules and tools assure robust solutions at extremely low cost.”
Several pre-competitive workstreams are already looking at this in international standardisation groups and the CBI, he said.
