The life of a lead-acid storage battery depends on the use to which it is put and on the care it receives. With good care, it will last several years; with little or no care, it may be ruined in a month. The important rules for battery care are as follows:
1. Test storage batteries periodically. Always wear eye and clothing protection to shield yourself from battery acid.
2. If a battery is completely discharged, recharge it immediately.
3. When charging a battery, select a charging rate consistent with the time available for charging. When time is available, use the normal rate indicated in the product manufacturer’s literature.
4. If it is necessary to charge a battery at a very high rate, keep a careful check on the temperature of the electrolyte and never let it exceed 110°F. If cells release gas freely, reduce the charging rate to the normal rate.
5. Never try to charge batteries to a definite specific gravity. Maintain the charge until the same specific gravity reading is indicated at three successive half-hour intervals.
6. By the regular addition of distilled water only, maintain the level of the electrolyte above the top of the separators according to the manufacturer’s specifications. Rapid deterioration of a battery will result if the electrolyte level is allowed to remain below the top of the separators. Usually, maintenance-free batteries do not require the addition of water.
7. Add distilled water immediately before recharging a lead-acid battery. In the process of charging a traditional battery, the water in the electrolyte is changed into hydrogen gas and oxygen gas that escape through the vent holes. This water must be restored so that the level of the electrolyte is maintained. Maintenance-free batteries do not experience this electrolyte loss.
8. Never use a match to provide light when checking the electrolyte level. Hydrogen and oxygen mixed together are highly volatile. The area used for recharging must be well ventilated.
9. Never disconnect the leads to a battery while it is on charge. The spark that occurs at the terminals may ignite the gas and cause an explosion. Many times, a battery is to be charged while permanently mounted in position, such as in an automobile, where the negative terminal may be connected to a frame or an engine. To reduce the chance of an explosion, the negative lead of the charger should be connected to the frame instead of to the terminal.
10. Never take a specific gravity reading just after adding distilled water to a battery. Addition of distilled water dilutes the electrolyte and lowers the specific gravity. A reading then would indicate a state of charge below the actual condition of the battery.
11. Avoid spilling electrolyte when testing a battery with a hydrometer.
12. Never add acid or electrolyte to a battery unless it has been definitely determined that some electrolyte has been lost. If it is ever necessary to prepare electrolyte, remember that acid must be added to water, and must be added slowly.
13. When placing a battery on charge, do not remove the vent plugs. The plugs prevent acid spray from reaching the top surface of the battery and allow the gases to escape as noted in number 7 previously.
14. Remove deposits that may form on the terminals of a storage battery so that the metal will not be eaten away. The presence of a greenish-white deposit on battery terminals indicates corrosion. Remove this material by thoroughly cleaning the affected parts with a wire brush. Apply a strong solution of baking soda and water to all corroded parts to neutralize any acid that remains. Wash the battery with fresh water and dry with compressed air or a cloth. Finally, coat the terminals with petroleum jelly or other suitable material.
15. Do not draw a heavy discharge current except for short intervals of time. If high current is needed for a long period, use additional batteries connected in parallel.
16. Test storage batteries more frequently in very cold weather than in warm weather. A discharged battery freezes easily.