Hi, Calbai the best way to charge a battery is slowly. I like to use this analogy, would you rather be awakened from a deep sleep with gentle nudging or a violent kick in the rear.
1. Remove battery and check for corroded or damaged terminals clean any dirt, corrosion or electrolyte that is on top of the battery as this will cause premature battery drain, inspect for cracks and swollen/expanded sides which are a sign of overheating and replacement should be seriously considered.
2. Acid plate type batteries should be checked with a hydrometer with recorded readings for each cell to be compared with after charging readings and for sulfation, the cell will appear milky, and incorrect acid level. Fill low levels with distilled water to upper level and remove acid from over filled cells with hydrometer until the level is at the upper mark and dispose of acid in the sink mixed with a quart/litre of water.
3. Connect a voltmeter set on the DC scale to the battery and record the reading for comparison after charging.
4. Attach a drain hose that is not pinched, kinked, or plugged to the nipple on acid plate type batteries and let the other end hang into a plastic or styrofoam cup.
5. Connect a 1-2 amp trickle charger that has automatic charge rate reduction if possible and let charge for 24 hours.
6. After charging recheck each cell with a hydrometer a 100% fully charged cell will have a specific gravity reading of 1.270-1.280 and 1.180-1.190 has only a 25% charge battery should be load tested and considered for replacement if necessary. Reconnect your voltmeter and
any readings in the 10-volt range means you have a dead cell and the battery needs to be replaced. Readings between any 2 cells of 50 points or more indicate the battery has failed and needs to be replaced.
7. No maintenance AGM or GEL batteries need to have a voltmeter reading of 12.8-13 volts for a full 100% charge and 12.2 volts is only a 25% charge and should be load tested and replaced if necessary.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have nice a day.
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