[ninja_geezer]

ok maybe im missing something on this new car .

so i suspected the battery not fully topped up when i got the car as i thought what was the battery doing between may ( finish build )

and early october collected,i do a lot of short journeys in town also i never use stop start always disable .

a couple of times on starting seemed a tad lethargic so i thought it would top it up .

left it on my smart charger at an indicated 8.5 amps for 6 hours so far today and battery only read 12.2 volts.....still charging it says at 8.5 amps.....i was under the impression a fully charged AGM battery was 13v correct me please if i am incorrect.

i then thought i would see what the voltage would go to when engine running so i tested with multimeter again and still 12.2 v at the battery,,,,on all my other cars it has always jumped up to 14v + when charging via alternator....like i said maybe this is a different beast to my other cars.

[BG42]

So one thing is if its colder out direct injection can take a second to start. Not sure your current weather situation but could be part of it.

[ninja_geezer]

Originally Posted by BG42

So one thing is if its colder out direct injection can take a second to start. Not sure your current weather situation but could be part of it.

current temps been between 5c and 11c

[danallxt]

Yes, This is not like "traditional" vehicles.
BMW has been using a technology called IGR (Intelligent Alternator Control) for many years. Simply put, it "generally" does not charge the battery to its full potential. It maintains a lower SoC. The alternator is decoupled from operation during most driving. It's much too complex to get into here, but some basics:

It uses an energy management system that only charges in a conventional way when the SoC (State of Charge) is below a specific threshold. Other than that, the alternator only supports the battery SoC as it is, unless we have overruns, coasting, braking, within our driving, when SoC is increased. In contrast to conventional charge control, the intelligent battery control avoids a 100% charge.

From BMW tech article:
IGR-Medium takes place in the phase between (60% and 80% SoC). The alternator only provides sufficient energy for the electrical loads in the drive phases. The battery is no longer charged. The voltage in the electrical system is maintained.

IGR operates to its full extent as soon as the (80%) limit is exceeded. This means the load on the alternator is fully relieved during the drive phases (IGR-High), neither the battery is charged nor is the electrical system supported. The alternator charges the battery with maximum possible power (IGR-Low) during the overrun phase and is able to charge the battery far beyond (80% *).

Three basic IGR conditions
IGR-Low: The vehicle is in the overrun (coasting) phase, electrical energy is fed to the battery.

IGR-Medium: The battery charge has reached a sufficiently high level, battery discharge is avoided, the energy required for the electrical loads is provided by the alternator.

IGR-High: The vehicle is accelerated, the energy required for operation of the electrical loads is provided by the battery.

What this means is that after "normal" driving you will never see your battery at 13.1 volts, as the norm is 60-80% SoC Also "normal" even state steady speed driving will not generally be providing charge to the battery. And yes, short trips will result in a pretty low battery SoC.
I most often see mine generally around 12.2 volts at rest.

Reasons for the above?
1) More efficient operation with alternator being decoupled most of time...gas mileage and performance benefits.
2) Supposed longer battery life by not always bringing it to full charge, which is partly why such a large battery?

[ninja_geezer]

Originally Posted by danallxt

Yes, This is not like "traditional" vehicles.
BMW has been using a technology called IGR (Intelligent Alternator Control) for many years. Simply put, it "generally" does not charge the battery to its full potential. It maintains a lower SoC. The alternator is decoupled from operation during most driving. It's much too complex to get into here, but some basics:

It uses an energy management system that only charges in a conventional way when the SoC (State of Charge) is below a specific threshold. Other than that, the alternator only supports the battery SoC as it is, unless we have overruns, coasting, braking, within our driving, when SoC is increased. In contrast to conventional charge control, the intelligent battery control avoids a 100% charge.

From BMW tech article:
IGR-Medium takes place in the phase between (60% and 80% SoC). The alternator only provides sufficient energy for the electrical loads in the drive phases. The battery is no longer charged. The voltage in the electrical system is maintained.

IGR operates to its full extent as soon as the (80%) limit is exceeded. This means the load on the alternator is fully relieved during the drive phases (IGR-High), neither the battery is charged nor is the electrical system supported. The alternator charges the battery with maximum possible power (IGR-Low) during the overrun phase and is able to charge the battery far beyond (80% *).

Three basic IGR conditions
IGR-Low: The vehicle is in the overrun (coasting) phase, electrical energy is fed to the battery.

IGR-Medium: The battery charge has reached a sufficiently high level, battery discharge is avoided, the energy required for the electrical loads is provided by the alternator.

IGR-High: The vehicle is accelerated, the energy required for operation of the electrical loads is provided by the battery.

What this means is that after "normal" driving you will never see your battery at 13.1 volts, as the norm is 60-80% SoC Also "normal" even state steady speed driving will not generally be providing charge to the battery. And yes, short trips will result in a pretty low battery SoC.
I most often see mine generally around 12.2 volts at rest.

Reasons for the above?
1) More efficient operation with alternator being decoupled most of time...gas mileage and performance benefits.
2) Supposed longer battery life by not always bringing it to full charge, which is partly why such a large battery?

Many thanks that has helped a lot.......

[Stanim]

Originally Posted by danallxt

Yes, This is not like "traditional" vehicles.
BMW has been using a technology called IGR (Intelligent Alternator Control) for many years. Simply put, it "generally" does not charge the battery to its full potential. It maintains a lower SoC. The alternator is decoupled from operation during most driving. It's much too complex to get into here, but some basics:

It uses an energy management system that only charges in a conventional way when the SoC (State of Charge) is below a specific threshold. Other than that, the alternator only supports the battery SoC as it is, unless we have overruns, coasting, braking, within our driving, when SoC is increased. In contrast to conventional charge control, the intelligent battery control avoids a 100% charge.

From BMW tech article:
IGR-Medium takes place in the phase between (60% and 80% SoC). The alternator only provides sufficient energy for the electrical loads in the drive phases. The battery is no longer charged. The voltage in the electrical system is maintained.

IGR operates to its full extent as soon as the (80%) limit is exceeded. This means the load on the alternator is fully relieved during the drive phases (IGR-High), neither the battery is charged nor is the electrical system supported. The alternator charges the battery with maximum possible power (IGR-Low) during the overrun phase and is able to charge the battery far beyond (80% *).

Three basic IGR conditions
IGR-Low: The vehicle is in the overrun (coasting) phase, electrical energy is fed to the battery.

IGR-Medium: The battery charge has reached a sufficiently high level, battery discharge is avoided, the energy required for the electrical loads is provided by the alternator.

IGR-High: The vehicle is accelerated, the energy required for operation of the electrical loads is provided by the battery.

What this means is that after "normal" driving you will never see your battery at 13.1 volts, as the norm is 60-80% SoC Also "normal" even state steady speed driving will not generally be providing charge to the battery. And yes, short trips will result in a pretty low battery SoC.
I most often see mine generally around 12.2 volts at rest.

Reasons for the above?
1) More efficient operation with alternator being decoupled most of time...gas mileage and performance benefits.
2) Supposed longer battery life by not always bringing it to full charge, which is partly why such a large battery?

What is the avg battery life for the vehicle under normal conditions?

[danallxt]

Originally Posted by Stanim

What is the avg battery life for the vehicle under normal conditions?

I have no idea, this model has not been out long enough to get a meaningful "average". Plus it will vary a lot by driving conditions etc. Heat is a real killer of batteries so you would have climatic variations.

Normally i would expect 5-7 years, but this is not a normal situation.