Last year I wrote an article about 48 volt batteries and that Audi had started to fit them to their SQ7 model. Batteries like other automotive technologies were stuck in a time warp for decades and recent developments have meant that the humble battery has been given some steroids to cope with the ever power-hungry systems on cars.
Mercedes-Benz has announced they will use a 48v system on some of their updated models. They have also announced yet another group of vehicles to be built alongside the A, B, C, E, G, GL, S, SL, V and X class vehicles. I’m sure I have missed some out of that list – it seems the German manufacturers namely Mercedes-Benz, BMW and Audi are determined to make a million different types of car! The new range is called the EQ and will be purely electric powered.
To add to the mix, Mercedes-Benz will use 48v systems on C class hybrids, a new CLS and the new S Class will have the system modified for their petrol and diesel saloons as well. That all sounds great – however on the S Class, the 48v systems are going to be powering the ancillaries and the starter motor/generator rather than the electric motors directly. The AC and the power steering systems will run off this system too.
It looks like this technology is not yet ready for a full blown motor and the C and CLS models will have a “mild” 48v hybrid system. The term “mild” is interesting because the vehicle uses two electrical systems: the 48v for some equipment including the starter motor that also acts as a generator and then a traditional 12v for everything else including the hybrid motor. The higher voltage system uses a converter to feed the lower voltage equipment.
So the generator uses the engine to create power that is then converted to a lower voltage to run the hybrid motor that provides the fuel efficiency required. The downside is that the car has to have extra kit added to make it all work which adds weight to the vehicle. The upside is that we will soon see the hybrid motors running with 48v power and the “old” 12v systems will be removed to become another historical feature of cars!
I would expect the EQ series to be fully 48v very soon without any internal combustion engine at all.