Battery charging voltage?

[ebruhn]

Have not seen much chatter here about battery charger voltage settings. I understand there are different setting for different type batteries. I am most concerned about wet cell, lead acid batteries. I read on the solar threads about 14.8 volts being required by battery manufactures for fully charged batteries, but no one seems to comment on chargers and weather they do indeed do fully charge to 14.8 volts as recommecded by manufacters.

My interest in this stems from checking my Magnum inverter/charger model MS2812 settings and found out it was factory default set at 14.5 volts.

i would be interested in comments.

Earl

[Shadowcatche]

The best source of information is the battery manufacturer themselves and one resource that demystifies the whole process and tells you who actually manufactures your battery is Car and Deep Cycle Battery FAQ, Battery Manufacturers and Brand Names List
Another source which shows the battery charging algorithms Battery Basics - Batterytender.com
The Solar that really works in the boondocking thread has a very complete discussion on this subject.

[wa8yxm]

If your converter is factory set to a SINGLE voltage, then the one thing I know for a fact is that it is the WRONG voltage... Because there is no SINGLE voltage that is correct.

Most modern converter/chargers are 3-state, In the first stage (BULK) they watch voltage but limit current (IE: if it is an 80 amp converter, you don't want to be putting out 100 amps for long) This is called BULK or BOOST mode depending on the company. In this mode the battery is fairly rapidly brought up to around 90% charge

Once the voltage hits a "Roof" it switches to monitoring current and limiting voltage, this is called Absorption Current is now much lower, but this is where the last 10% is done... Once that's achieved the voltage drops to Float. In this mode IDEALLY not battery current flows (in practice there is a tiny flow)

So if your converter is a single stage (Voltage) type.. Upgrade. If the voltage is high enough to achieve full charge it will over charge and damage your batteries, and if it's not, well that's not good either.