Charging Instructions for a Deep Cycle Battery

by Cassandra Tribe
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Deep cycle batteries are designed to withstand discharging of up to 80 percent of their stored energy over a period of time. They are not, like regular batteries, designed to provide a high burst of charge for uses such as cold starting. Typically you can find deep cycle batteries in use with golf carts or as RV house batteries, where power is needed but not in powerful starting bursts. The charging instructions for a deep cycle battery are not complicated, but there are a few tips to keep in mind.

Step 1

Disconnect the deep cycle battery (if necessary; stored batteries most likely are not connected to anything) and move it to a clean dry place that is well ventilated.

Step 2

Use a flat head screwdriver to remove the covers of the battery cells so you may check the electrolyte levels of each cell. Even if your deep cycle battery is "sealed," you can still remove the cell covers. The covers will either be in the form of individual cell plugs or one large cap that covers all the cells. Pry up on the cap to remove it. Make sure you are wearing rubber gloves and protective eye glasses in case any of the interior acid splashes out of the cell.

Step 3

Insert the tip of your hydrometer into a cell and draw fluid into the hydrometer. Read the hydrometer according to the instructions provided with it. Some types of hydrometers use floating balls to indicate whether the cell is low on water, and some will have a needle gauge. A certain level of water is necessary to support the electrolytes in the battery and allow the battery to work properly. If the cell is low, add distilled water. After you have tested each cell, recap the cells.

Step 4

Set your battery charger to a slow or trickle charge and select whether you are charging a 6, 12 or 24 volt deep cycle battery. If your battery charger has the option to set the voltage for the charge, set it to 20 percent of the rated amp per hour rate of the battery you are charging. The amp per hour rate will be written on the top or side of the battery. Deep cycle batteries charge best when the charge flow is at its lowest.

Step 5

Connect the cables from the charger to the terminal posts on the battery. Make sure that you connect the positive cable to the positive terminal first. The positive sides of each are normally indicated with either a red color wire or cover or a plus sign. Then connect the negative cable, indicated with a minus sign, to the negative terminal.

Step 6

Turn the charger on. Wait 20 minutes and then check the charge meter on your battery charger. It will take this long for the charger to get an accurate reading of the actual charge still existing in the battery. If your battery charger has a voltage regulator, you can leave the battery and come back at your convenience as the charger will automatically shut down when the correct voltage is reached. If your charger does not have a regulator, monitor the charge meter on an hourly basis until the full charge is reached and then disconnect the charger.

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