hulio516

My 12v 7 amp gel cell starter battery is on the dead side. How long should I charge it back up using the 600 mah wall charger?

hulio

CGRetired

My Feedback: (1)

Do the math, Hulio. 7 amps is 7,000 milliamps. If your charger is a 600 milliamp charger, well, 600 goes into 7000 11.66 times. Add about 15% for overhead (heat dissipation, and other overhead consumption) you get about 13.5 hours.

CGr.

Rodney

If you have let it discharge to deeply, you may have damaged it beyond restoring. Always recharge any Pb based 12 volt (6 cell) battery as soon as it drops to 11.9 volts. Two things will kill your gel cell quickly, deep discharge or to fast a charge. Never charge at more than 0.1C (700 milliamperes in your case) unless you are monitoring the battery temperature where you can stop the charge as soon as the temperature rises appreciably. If you are using the proper charger, a limited current/maximum voltage charger, you can leave the charger connected all the time as it will automatically cut off as the voltage rises to the set limit.

hulio516

I charged up my 7 amp gel cell battery for 13.5 hours with the 600 mah charger and it works fine. Now it will turn over my 75ax engine with no problem! Unlike last year it wouldn't even turn over any of my engines with the starter. Last year I was only giving it about an 8 hour charge and the 12v battery is 5 years old. I guess the 13.5 hour charge did the trick rather than just an 8 hour charge.

Thanks for the help,

hulio

jester_s1

Lead batteries don't like to be pulled down. Top it off every time you fly. Better yet, buy a battery tender to keep it topped off all the time.

hulio516

My gel cell 12v battery was so low before I charged it back up that it wouldn't even turn my starter over one time and it wasen't even up against an engine. So, the 13.5 hour 600 mah charge made it like new again after being 5 years old.

hulio