According to Autocar magazine, BMW has filed a patent for a hybrid car that actually uses a split engine for its powertrain.
What is this exactly?
Ok, a 'traditional' hybrid car basicly has a gasoline engine mated to an electric motor. The electric motor will either add extra power to the gasoline engine, or actually sometimes take over from the gasoline engine and run the car on its own.
But in BMW's 'split hybrid' setup there would be a traditional gasoline-electric combination and a third regular gasoline engine. The third engine would sit dormant unless even more power was needed and then it turns on and gives more juice.
The actual displacements and cylinder sizes haven't been revealed, but one would assume each engine would be low displacement with only 2 or 3 cylinders.