In 2022, BMW is rumored to launch the second generation 3 Series plug-in hybrid which is expected to be a highly revolutionary project. The intermediate step is the 2016 BMW 3 Series Hybrid which will arrive in showrooms next summer.
According to Autocar, BMW is not only embarking in a radical engineering of its hybrid tech, but also for all future models, including the Rolls Royce.
The new architecture of BMW cars moved away from the welded steel bodies and engines that drive the rear wheels via conventional transmissions, and onto platforms made from a mix of steel, aluminum and composites and powertrains that use electric motors as the primary drive source.
These materials are variously bonded, glued, screwed and riveted together. Using composites in strategic structural areas, such as the roof pillars and sills, allows thinner-skinned steel pressings to be used, saving weight and improving rigidity.
The internal combustion engine is said to spend most of its time acting as a generator and running at peak efficiency.
BMW will also look at significantly improving the car’s aerodynamics, as well as looking at connected technology with 3D navigation allowing the car to anticipate hills and use downhill coasting to reduce energy use and recharge its batteries. An innovative suspension is also planned, with a lower ride height on the highway and active aerodynamic air intakes.
All these changes are as strategic as they are imposed by the EU fuel consumption regulations. In 2021, car makers have to hit a fleet average CO2 output of 95g/km, with a range of between 85g/km and 110g/km for the various brands. Then in 2025, a new CO2 target will be set, rumored to be even stricter.
Most likely, the “35up” or CLAR architecture is the one being referenced by BMW. The new platform is lightweight and modular, allowing to make all of its cars from the 3 Series upwards plug-in hybrids. The new hybrid powertrain uses two electric motors, one on the rear axle and one mounted directly behind the engine.
The large battery pack sits in the center tunnel with the front-mounted combustion engine acting as a generator in most driving situations.
The front electric motor is key to the new powertrain since in normal use, it drives the front wheels via a still-secret new type of transmission. At speeds above 50mph or so, the engine ‘assists’ the electric motor by attaching itself to the new transmission and helping to drive the front wheels at motorway speeds.
BMW has yet to reveal the full details, but the engineers hint that the combustion engine would probably be driving the front wheels only about 10 per cent of the time in a typical journey. The engineers said this allows them to run the engine at ‘Lambda 1’ for 90 percent of the time, leading to higher fuel efficiency.
With the engine working less time mechanically, its construction can be simplified and less expensive to build than today’s motors.
To retain its Ultimate Driving Machine slogan, BMW will offer a tight package underneath the car. The heavy battery is placed low down and in the center of the car and the new generator/motor will often be lighter and mounted farther back in the front. So we expect to see the same exceptional 50-50 balance.
One interesting point brought is the potential change in monikers. With performance dictated mainly by the electric motors, BMW could switch badging to reflect torque output, so ‘345’ would be a 3 Series with 450Nm.
What You Might See In 2022
Citing BMW engineers, Autocar also says that a new-generation BMW engines might drop the turbocharger and the accompanying intercooler system or the Valvetronic system, since the torque will mostly be provided by the two electric motors. This ties into an emission control system being less complex and a lighter engine, so therefore a lighter car.
The new transmission is unlikely to have more than three ratios and could be a mechanical planetary system.
Since electric range is the key to the BMW electric vehicles, a larger battery pack is needed. This will fit neatly in space freed up by the removal of the propshaft and the use of a smaller fuel tank.
The rear differential might also be dropped, while the braking system can be smaller and lighter, thanks to the braking capability of electric motors.
At least 100kg are expected to be shed from the upcoming 3 Series hybrid to the next one.
This new hybrid powertrain offers part-time and permanent all-wheel drive and can be scaled across all models, from a 3 Series to an X5 and even to Rolls Royce family.
The future of cars is changing and the next ten years will be significant for the entire industry. Technology is growing by leaps, bounds to change the future for the automakers and its new customers.