landyacht318 wrote:
Many modern Autos intentionally keep the battery discharged to the point that when the driver lets off the gas, or hits the brakes, the battery can then accept higher amps when the voltage regulator commands 14.5+ volts. This acts as a poor regenerative braking MPG enhancer and a battery that basically is Never fully charged
This results in the continuous partial state of charge cycling of starter batteries, and short lifespans and not long after, whining customers demanding new batteries under warranty which then eats into profits.
I am a retired (12 years) automotive engineer. I worked on Powertrain Control Systems. "Smart charging" System were just becoming "standard' when I retired so things may have changed since then.
#1 smart charging systems goal is to
improve fuel economy. #2 is to extend battery life in the midst of multiple short high current loads.
Now a days, voltage regulators are "dumb". All they do is turn on and off
(or regulate) the field current at the direction of the PCM. Check any car built in the past ten years. Turn the headlights on for 5 minutes and then start the car. Connect a DMM to the battery and watch the voltage. It will start high (>14V) but over the course of 5-10 minutes it will drop down to <13.5V. This is all being controlled by the PCM.
Many current cars have battery "state of charge" and/or true battery load
(current) sensors feeding data to the PCM.
Multiple re-starts from a "start-stop" system will have very little impact on the flood starting battery.
