At the excellent Electric & Hybrid Vehicle Conference here in Sindlefingen, Germany, 48V mild hybrids are rightly a strong focus. The consensus is that we are quickly moving beyond the opening shots that can reduce carbon dioxide by up to 14%. These tend to involve belt starter generator BSG, no electric drive modes, PO/1 positioning on engine, 480Wh 48V battery and 12 kV supplied. This was described as little more than an upgraded stop-start albeit with cold start, fast start, quietness and fuel economy.
Now it is realised that four pure electric modes with considerable autonomy will happen with 48V mild hybrids moving up to 25kW or more, up to several kWh batteries, giving up to 40% carbon dioxide reduction (Valeo though maybe even more). Ambitions go well beyond an electric supercharger and electric steering being enabled. 48V on steroids will easily power a profusion of electrics from heated catalysts to many new devices improving economy, performance and ride, including active suspension. A few of these things were "whether" two years ago. Now they are all "when".
Daimler, Continental, Valeo, ADD Solution and others tracked their rapid progress on this journey with many other goodies proving possible too such as Borg Warner demonstrating 48V vectored steering of high capability though not the lowest cost. P2 position between engine and transmission is favoured now for the motor-generator because of adding such capabilities as excellent regenerative braking even with engine off, auto park even for manual transmission and pure electric sailing (active cruise), parking and creeping in traffic.
However, P3 and P4 positions for the integrated starter generators ISGs further down the car, often with two of them are also planned now. Another new emphasis is radical improvement of the internal combustion engines for 48V vehicles because currently they are repurposed standard products meant for use alone for rapid torque changes and therefore over-designed because the electric motor-generator increasingly does the heavy lifting despite this being a parallel hybrid configuration. The conference was surprisingly negative about series full hybrids with range extenders. Maybe some of the advanced range extenders will have a place in later 48V mild hybrids?
Optimisation of 48V mild hybrids will lead to further downsizing and down speeding we were told. AVL in a superb extended presentation calculated that the ideal ICE for 48V would add a mere 4.5 kg! This is getting dramatic, now going beyond the initial adoption in premium vehicles, such as Mercedes S Class, to even embrace city cycle and C Segment cars in the plans of the Tier Ones and OEMs. Indeed, at this conference 48V mild hybrids were correctly called conventional vehicles but in future, as they are reinvented, they will have to be referred to as electric vehicles. On IDTechEx projections based on extensive interviews, sales volumes will be formidable for at least ten years.
Bottom line for now is that 48V mild hybrids are first appearing in volume this year, with most of the action in Europe and the USA. They will increasingly steal the clothes of full hybrids with lower cost and easier introduction. However, what is not happening is abandonment of the 12V battery. In addition, lead-acid 48V batteries will not get any significant part of the action. Lead is a four letter word nowadays and so there are both image and technical reasons why 48V lead-acid batteries now offered by many suppliers will be losers. There was even talk of a plug-in 48V mild hybrid but contactless inductive charging of any EV was seen as an extra not a replacement for plugging in because fastest charging is needed. Indeed, charging a car in minutes is expected one day meaning fuel cell vehicles further lose their justification, though Daimler saw them in long distance 30 tonne trucks with high voltage.
For more see the IDTechEx report, Mild Hybrid 48V Vehicles 2017-2027. Beyond 48V, in the progression to PHEV then plug-in and contactlessly charged pure EVs there is a new end game opening up. It is Energy Independent Electric Vehicles (EIV) and for all of that progression attend the unusually futuristic Electric Vehicles: Everything is Changing conference at IDTechEx Show! with its 200 exhibitors, 3000 serious paying delegates, nine parallel conferences and, on the day before and day after, 25 optional masterclasses. For example, there are six EIV presentations from aircraft to cars and boats. Toyota, Daimler and many hot new start-ups will give the future roadmap for all forms.