11. CAN I INCREASE THE LIFE OF MY BATTERY?

Last Updated on July 11, 2004

The typical overall life of a good quality, well maintained battery is:

EXPECTED BATTERY SERVICE LIFE

Here are some tips to increase car or deep cycle battery service life:

11.1. Protect your car battery from high under hood temperatures with a heat shield or cover, keeping it full charged at all times, and well maintained are the easiest ways to extend it's life. In hot climates and during the summer, the electrolyte levels need to be checked more frequently. In a study conducted by the Society of Automotive Engineers (SAE), the under hood temperature has increased more than 30% since 1985.

Chrysler studies have shown that relocating the battery outside the engine compartment has increased the average battery life by eight months. Relocating the starting battery to the trunk or passenger compartment, as Mazda did in their Miata a number of years ago, is becoming more popular by the car manufacturers to protect the starting battery from the high under hood temperatures. However, sealed VRLA AGM or Gel Cell type batteries must be used because they normally do not produce gas when recharged. If a gel cell is used as a starting battery, the charging system voltages are very critical, may need to be lowered to keep from overcharging the battery.

11.2. If possible, recharge a deep cycle battery every day it is used and as soon as possible after each use. When not in use, maintaining the battery's State-of-Charge at 100% by continuous float charging is best way to prevent permanent lead sulfation. If continuous float charging is not possible, recharge before the State-of-Charge drops below 80%. Permanent sulfation kills approximately 85% of all deep cycle batteries. (Please see Section 16.)

11.3. Reducing the average DoD (Depth-of-Discharge) by proper deep cycle battery sizing will significantly increase a deep cycle battery life. For example, a battery with an average of 50% DoD will last twice as long or more as an 80% DoD; a 20% DoD battery can last five times longer than one with a 50% DoD. Golf cart batteries will typically have an average 225 cycles at 80% DoD and 750 cycles at 50% DoD. Avoid DoDs that are greater than 80%. The "sweet spot" (optimum DoD for the greatest amount of power produced over the service life) is generally somewhere between 20% DoD and 60% DoD. For the AGM battery below the "sweet spot" is approximately 22.5% DoD.

AGM Life Cycles vs. Percent Depth-of-Discharge (DoD)

[Source: Concorde]

11.4. Never discharge below 10.5 volts. An adjustable low voltage disconnect set for an 80% DoD or less can limit the maximum Depth-of-Charge and protect the batteries and electrical appliances. Leaving your lights or other accessories on and fully discharging a car battery can ruin it, especially if it is a sealed, wet Maintenance Free (Ca/Ca) type or it is frozen. If this should occur, you should let your battery thaw, if frozen, fully recharge it with an external charger, remove the surface charge, and test the battery and charging system to determine if there is any latent or permanent damage.

11.5. In extremely cold climates, keep the car battery fully charged, the engine and battery warm, and use low viscosity synthetic engine oil. Use AGM or Ni-Cad batteries in sub-zero temperatures.

11.6. In hot climates use the "hot climate or "South" versions of car batteries. They have special plate and connecting strap formulations, lower Specific Gravity levels or increased the amounts of electrolyte to provide more "cooling". Using non-sealed Low Maintenance (Sb/Ca) car batteries is encouraged because you can add water. "Watering" is required more often and add only distilled, demineralized or deionized water or, in a emergency, rain water. The plates must be covered at all times to prevent an internal battery explosion or sulfation. Do not overfill, and keep the top of the battery clean. Do NOT add electrolyte (battery acid) to a battery unless some electrolyte has spilled. If the Specific Gravity levels are increased beyond the battery manufacturer's recommended limit, there will be a higher capacity level, but more maintenance and a shorter service life.

11.7. Turning off all unnecessary accessories, rear window heater, climate control, and lights before starting your car will decrease the load on the battery while cranking, especially when it is cold.

11.8. Reducing the parasitic (key-off) load to below 75 milliamps.

11.9. In cold climates, increasing the diameter of the battery cables will reduce the voltage loss.

11.10. If required, equalize wet and some AGM batteries. (Please see Section 9.)

11.11. For vehicles not used at least once every two weeks, continuously float charge the car battery. (Please see Section 13.)

11.12. Provide adequate ventilation. High ambient temperatures above 80° F (or 26.7° C) will shorten battery life because it increases positive grid corrosion, growth and VRLA "thermal runaway".

11.13. Recharging slowly using the manufacturer's recommended voltages (compensated of temperature) and current.

11.14. Avoid shallow (below 10%) discharges of deep cycle batteries because lead dioxide builds up on the positive plates. In other words, you should discharge a deep cycle battery between 10% DoD and 80% DoD.

11.15. Use batteries with thicker plates and reduce the number of discharge-charge cycles.

11.16. Apply the correct battery type for the application, that is, starting for starting applications and deep cycle for motive and stationary deep cycle applications.

<<<Previous     [Home]     [Top]     Next>>>