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[schoppy]

I guess I have never checked the voltage of my vehicles batteries when they are running but my volt meter on the dash doesn't show 14 volts. I have checked voltage on batteries when I have had smart chargers on them and they were right around 13.2 to 13.4 volts which is just about right for a fully charged battery.

Finally got my whole house air to air heat exchanger running today after just hanging there for 4 years. We'll see if it reduces the humidity like I'm hoping.

[juddspaintballs]

From what I remember, a fully charged automotive type battery should read 12.7 volts.  12.0 volts is heavily discharged.  To charge a battery to 12.7 volts, the alternator needs to exceed that voltage to the tune of at least 0.5v, or right around 13.2 volts.  Most alternators for 12 volt systems put out between 13.4 and 14.4 volts to charge the battery fully, and often newer vehicles will sense the voltage at the battery and regulate the voltage down as the battery nears a full charge.  This is why the reading you'll see on your dash quite often is in the low 13's (that, and the point in the electrical system where they test the voltage).  The excess voltage doesn't hurt the battery since it takes more than the fully charged voltage to charge each cell due to efficiency losses.  The water and acid help keep things cool in the cells, but eventually all batteries will die.  The lead and acid will react with each other enough that they can't react as strongly anymore and you'll get a battery that can't hold full charge or a dead cell that will allow you to read proper voltage but will not pass enough amperage to start a motor.