[DNK76]

You can do your own research with bmw with equipment
AGM, (S1CCA AUTO START STOP FUNKTION), (S1CDA BRAKE REGENERACJA ENERGII )
Plug the voltmeter into the lighter and study the voltage as it changes
from driving mode:
- from the battery charge level (ie not charged is the voltage in the range of 14.7 - 14.9V sometimes even 15V
As the battery is low, the voltage is below 13.8V
- from the temperature you can see the temperature is falling, and the voltage is rising
Read about BSD and ibs in ISTA
- The voltage changes depending on the motor load
 Any engine braking increases the voltage to store energy
The same sudden acceleration is to affect the least possible load on the engine, thus lower fuel consumption, then the tension decreases,
Such a BSD principle
In addition, each charger does not charge with DC, it in conjunction with the battery, straightens the current, so while charging, the battery charges the accumulated energy, so it is desirable to increase the charging voltage
and 13.8V chargers have to keep the battery charged
The loading capacity of the AGM is 14.5V dp 14.9V
All bmw chargers have a voltage setting of 14.8V
on the charger on the terminal it is 14.6V at low current
Sore for weak English