Battery Overcharging

[Bill Drent]

When I bought my 1980 Cat 22 a few days ago, the battery was discharged. The boat has a portable solar panel which had a corroded plug that wasn't passing electricity. I repaired the plug and after one day, the voltage had risen to about five volts, after two days to about ten volts. I returned today, after two days and got a reading of about 1 volt. The solar panel is still putting out 23 - 26 volts. Is it possible I overcharged the battery and killed it? Has anyone had experience with overcharging with solar panels?

 

[Stu Jackson C34 1986 #224]

Solar Panel on C22

BillPart of the answer is how big your solar panel is and how big the battery is. How old is the battery?The solar panels should have regulators to avoid over-voltage to the batteries, if the size of the panel exceeds 1 1/2% of the battery capacity in amp hours.See the West Marine Advisor, a very good, quick writeup about solar panels.Scroll down to electrical and click on solar panls. Also read about battery charging.Stu

 

[Don Flowers]

Bad Battery

If you measured battery voltage at 5 volts and 10 volts the battery was already bad. Once the voltage was allowed to get below around 10 volts the battery was trash. I am not sure about the solar charger, but that voltage of 23 to 26 volts sounds high. I can accept a voltage in the high teens, but not in the mid twentys. Don Flowers Rockport, Tx.

 

[Bill Drent]

Thanks for the info

I'm not sure my voltmeter wasn't part of the problem (bad battery there too). I pulled the battery and brought it home to charge. After 24 hours the charger says it is charged. Will put it back into the boat tomorrow to see if it is OK, or if I need a new battery, or if there is an electrical problem draining it.Thanks to everybody for your responses...