Before installing the battery system check for physical damage, electrolyte level, state of charge, etc..

Insure that the battery compartment is well vented and will prevent the entrance of water, dirt, etc.. Believe it or not one of the most severe abuses that a deep cycle battery will receive is cleanliness, or lack of it. Dirt, corrosion, water and acid will rob a battery of a full life. A clean well kept battery will extend the useful life of the battery. Remove dirt and dust accumulations from the top of the battery. Wash the top of the battery with clean water and soda solution to neutralize any acid accumulation. Approximately 100 grams to a liter of water is sufficient. Baking soda used in the home is satisfactory. Rinse with clean water and dry. Ensure vent caps are in place and no soda solutions enters the battery.

Before installing the batteries, clean the contact surfaces of the lead terminal post and battery terminals with a wire brush. Apply a thin coat of Vaseline to all contact points and connector bolts. After all connections have been securely tightened, they should be gone over and tightened a second time.

Check the height of the electrolyte twice a month. If necessary replace with approved water only. Many times domestic water is satisfactory. Water with a high mineral content is not satisfactory. Do not use water that is difficult to create a lather when washing your hands with soap and water.

Never fill the cells above the bottom of the vent well (must be at least 1 inch below the top of the vent opening). Over filling will cause loss of electrolyte and reduce the battery capacity. Never add acid to the battery.

Avoid over discharging of the battery as the useful life will be reduced. The rule of thumb is not to exceed 80 percent of the capacity of the battery. On a 12 volt system this would be approximately 11 volts. Remember over discharging or low voltage will also reduce the life of most electrical equipment.

Battery capacity is based on each cell having an electrolyte temperature of 77°F (25° C). Temperatures below 77° F reduce the battery's effective capacity and lengthen the time to restore to full capacity. Temperatures above 77° F will slightly increase capacity, but will also increase self discharge and shorten battery life.

If a battery becomes discharged the electrolyte can freeze. See list below.

Determining state of charge by voltage is more difficult as there must be no load or surface voltage present.

When taking specific gravity measurements, it is important to correct for temperature to get a true reading. As a rule of thumb, specific gravity will change by 0.0003 for each ten degrees Fahrenheit change in temperature above or below 77° F (25° C). Below 77° F subtract from readings and above 77° F add to the readings. As an example a reading of 1.265 at 67° F corrected for temperature would be 1.262 and a reading of 1.265 at 87° F corrected for temperature would be 1.268.

It is recommended that fully charged gravity and voltage readings be taken of each cell every month and compared with readings from the preceding period. The readings will indicate any marked difference in battery condition as well as differences between cells. A good rule of thumb is if there is 0.025 points or less between the high and low cell the battery is not defective. Low readings would indicate the battery being discharged.

Sometimes the battery may be operated between the middle range or it's capacity due to load demands and or lack of charging time. At least once every three to four weeks the battery system must be fully charged. During discharge sulfate is formed. If the sulfate is allowed to remain for too long a period it will become very difficult to remove and the battery system will not accept a charge.

For more information see bulletin #501.

The charging system can have a profound effect on the life of the battery. A high voltage setting can cause excessive gassing and water loss. Eventual damage to the battery system will take place. A low setting will leave the batteries in an under charged condition resulting in a loss of capacity and eventually the battery system may not take a charge. A proper setting will result in a minimum of water consumption and still able to maintain the batteries at full charge.

For more information see bulletin #507.

Remember batteries may expel explosive gases. Keep sparks, flames, burning cigarettes or any other ignition sources away from the battery system at all times.

Always wear a face shield when working near batteries.

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