German OEM Volkswagen will not switch to a single 48V power supply system in mild hybrids in the near future, according to Florian Kühnetz, development engineer at Volkswagen.
Volkswagen will focus on a dual voltage power supply comprising a 12V lead-acid battery and a 48V lithium-ion battery, said Kühnetz at the 2nd 48V automotive power supply conference in Düsseldorf, Germany.
“It’s too complex to shift entirely. You will always need two energy sources for redundancies,” said Kühnetz and added that a lot of car components are not ready yet for a total switch. The company will introduce a new 48V mild hybrid “within weeks.”
At the 48V conference, European automotive industry engineers discussed the feasibility of using 48V power supply systems in cars in order to reduce CO2 emissions.
Most of the German carmakers are developing a dual voltage architecture with a 48V lithium-ion battery and experiment with flywheels, supercapacitors and a 12V lead-acid battery. Moritz Märgner from Continental said that the main target should be to eliminate the need for a 12V battery.
In 2011, the five major German OEMs, Volkswagen, BMW, Daimler, Opel and Ford-Werke have agreed on the 48V development scheme “LV-148” in which the 48V level and test procedures are specified. The German Association of the Automotive Industry (Verband der Automobilindustrie) defined the initiative as a standard in December 2013. But progress has been slower than expected and the initiative is looking for more OEMs as well as Tier 1 automotive suppliers, to work with.
Prana Natarajan, researcher at Frost & Sullivan UK, said that while the five German OEMs are sticking with their decision to switch to a 48V system, several carmakers are still evaluating the advantages and disadvantages of the low-voltage system.
Christian Kunstmann, senior manager at General Motors Europe, said that there has to be economies of scale in sight to agree on industrial standardisation, otherwise the company will stick to its already applied internal standards.