How to Add Water to a Deep-Cycle Battery

by Larry Simmons
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A lead-acid deep-cycle battery is often found in operations where renewable energy batteries are in use. Used in a variety of vehicles from golf carts to RVs, and as backup power, deep-cycle batteries can be regularly charged and discharged without damage. Providing a deep-cycle battery with the proper maintenance should give you trouble free use for years. Refilling the battery is one of the more important procedures of the maintenance cycle. You need to check the water and refill it every six to 12 months, as needed.

Step 1

Examine the battery for current water levels. Look for a small square lead plate in each cell of your battery. This plate should be completely submerged in liquid. If it isn't, you need to add water to the cell.

Step 2

Disconnect the battery, removing any cables by loosening the bolts that hold the cable clamps in place using an adjustable wrench, and then pulling the cable from the battery post. Remove the negative cable first, followed by the positive cable. Examine the battery posts to which the cables are connected to determine which is the positive cable, marked with a "+" sign and which is negative cable, marked by a "-" sign.

Step 3

Unscrew and remove the fill cap on the top of the battery cell that needs refilling. Set the cap aside.

Step 4

Carefully pour the distilled water into the battery, submerging the lead plate in the battery cell completely.

Step 5

Fill the battery cell to the marked fill line on the side of the battery housing. Fill lines are usually located about an inch from the top of the battery cell.

Step 6

Screw the fill cap firmly back onto the battery.

Step 7

Reconnect the cables to the battery, starting with the positive cable, followed by the negative.

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