After taking my battery to the auto parts store to have it recharged, I found out it was fried. After the guy looked at it he told me my alternator was putting out too much power and I might need to have it replaced. This was after making the observation that the sides of the battery where solid and bulging. I have never heard of this. My doubts come from the fact that the same battery and alternator have been in the car for 2 years. Is it possible my alternator fried my battery?
You can destroy the battery if the alternator overcharges the battery. This has to do with the regulation circuit going bad.
Perhaps the most common external causes of premature car battery failure are (long term) undercharging and overcharging. I wouldn’t use the term “power;” I think it’s more accurate to say the alternator delivered excessive voltage. While the battery’s condition may be a clue to this, I would certainly measure the charging voltage with a test meter before condemning the alternator.
Power and voltage are interrelated. If the regulator circuit puts out more amps than the battery can absorb the voltage will spike due to the internal resistance of the battery. Voltage is easier to measure.
This excessive can and will cause gassing and boiling of the electrolyte and can destroy it.
We had a car in last week with this problem. Charging at 18V and had boiled away most of the electrolyte. New alternator and battery was the fix.
Back in the day, voltage regulators were seperate from generators and they could cause your problem. Since I have no idea how old your car is, it’s hard to say, but if the internal voltage regulator went bad, it could cause the problem.
When an auto battery starts going bad, the car’s computer can increase the voltage put out by the alternator in an effort to compensate. Some cars require a computer scan and reprogramming to force the voltage back down after the battery is replaced.