Is the 330i a Mild Hybrid?

VirtualM

Member
Just took possession of a new 330i LCI. When I coast or brake on eco pro mode or comfort mode, there is an indication on my screen that the battery is charging and a picture of the car rear tyre in blue. What does this mean?
 

v1p3r

Well-known member
It's the regenerative braking. So it stores energy in the battery when you brake by using the heat energy released by braking to charge the battery. It's just a visual indication what systems are doing what with regards to the EfficientDynamics functions. You will also notice if your aircon is on that it shows that function activated if you're in Eco Pro
 

Spanky

Well-known member
It's the regenerative braking. So it stores energy in the battery when you brake by using the heat energy released by braking to charge the battery. It's just a visual indication what systems are doing what with regards to the EfficientDynamics functions. You will also notice if your aircon is on that it shows that function activated if you're in Eco Pro

I was also only partially correct - see below!
 
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Benji

Well-known member
Ehm no, technically, there is no recuperation via brakes - this is only possible when an electric motor drives the wheels, so the motor can be used to brake the wheel and store energy. It is more an intelligent alternator strategy, specifically designed to use peak charging when on the over-run and braking. Over-run being the key to switching to maximum charging.

It basically means your alternator only charges your battery when you are decelerating and wont add load to your engine while accelerating. There is no recovery from your brakes

Being a bit of a nerd, an average 12V car battery (100Ah) can store about 1kWh of energy. The kinetic energy of a 2ton car moving at 120km/h is about 300 kWh. So this clever alternator strategy at best, can recover 0.3% of your kinetic energy if the battery is flat and you slow down from 120km/h. So it really doenst make much of a difference, but a small amount consistently can add up I guess.

The above assumes I have mathed correctly (highly unlikely)
 
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Spanky

Well-known member
Ehm no, technically, there is no recuperation via brakes - this is only possible when an electric motor drives the wheels, so the motor can be used to brake the wheel and store energy. It is more an intelligent alternator strategy, specifically designed to use peak charging when on the over-run and braking. Over-run being the key to switching to maximum charging.

It basically means your alternator only charges your battery when you are decelerating and wont add load to your engine while accelerating. There is no recovery from your brakes

Being a bit of a nerd, an average 12V car battery (100Ah) can store about 1kWh of energy. The kinetic energy of a 2ton car moving at 120km/h is about 300 kWh. So this clever alternator strategy at best, can recover 0.3% of your kinetic energy if the battery is flat and you slow down from 120km/h. So it really doenst make much of a difference, but a small amount consistently can add up I guess.

The above assumes I have mathed correctly (highly unlikely)

You are right, there is no harvesting happening, just intelligent alternator engagement/disengagement to recoup energy (kinetic) that would've been wasted under deceleration and coasting.

BMW literature claims up to 3% fuel saving when driving style is adapted to maximise it. Not bad!
 
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