Re: Is my battery showing normal aging, or does it have advanced altzimers?
Your battery is dying.
<br /><br />Only holding a 25% charge at 12v.<br /><br />About the average life of batteries in warm/hot climates.<br /><br />Fron
www.batterystuff.com :<br /><br />. Battery life and performance - Average battery life has become shorter as energy requirements have increased. Two phrases I hear most often are "my battery won't take a charge, and my battery won't hold a charge". Only 30% of batteries sold today reach the 48-month mark. In fact 80% of all battery failure is related to sulfation build-up. This build up occurs when the sulfur molecules in the electrolyte (battery acid) become so deeply discharged that they begin to coat the battery's lead plates. Before long the plates become so coated that the battery dies. The causes of sulfation are numerous. Let me list some for you.<br /><br /><br />Batteries sit too long between charges. As little as 24 hours in hot weather and several days in cooler weather.<br /><br /><br />Battery are stored without some type of energy input.<br /><br /><br />"Deep cycling" an engine starting battery. Remember these batteries can't stand deep discharge.<br /><br /><br />Undercharging of a battery, to charge a battery (let''s say) to 90% of capacity will allow sulfation of the battery using the 10% of battery chemistry not reactivated by the incomplete charging cycle.<br /><br /><br />Heat of 100 plus F., increases internal discharge. As temperatures increase so does internal discharge. A new fully charged battery left sitting 24 hours a day at 110 degrees F for 30 days would most likely not start an engine.<br /><br /><br />Low electrolyte level - battery plates exposed to air will immediately sulfate.<br /><br /><br />Incorrect charging levels and settings. Most cheap battery chargers can do more harm than good. See the section on battery charging.<br /><br /><br />Cold weather is also hard on the battery. the chemistry does not make the same amount of energy as a warm battery. A deeply discharged battery can freeze solid in sub zero weather.<br /><br /><br />Parasitic drain is a load put on a battery with the key off. More info on parasitic drain will follow in this document.<br /><br /><br />Here is some from
http://www.uuhome.de/william.darden/carfaq11.htm <br /><br />Here are some tips to increase car or deep cycle battery service life:<br /><br /><br />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.<br /><br /><br />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 should be used because they normally do not produce gas when recharged, but a vented (to the outside) wet lead-acid battery can be used. If a gel cell is installed as a starting battery, the charging system voltages are very critical, may need to be lowered to keep from overcharging the battery.<br /><br /><br />11.2. If possible, recharge a deep cycle battery each 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 lead-acid batteries not in weekly service. (Please see Section 16.)<br /><br /><br />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 example below the "sweet spot" is approximately 22.5% DoD.<br /><br /><br />AGM Life Cycles vs. Percent Depth-of-Discharge (DoD)<br /><br /><br />[Source: Concorde]<br /><br /><br />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 to the plates, separators or case due to the expansion of the frozen electrolyte.<br /><br /><br />11.5. In extremely cold climates, keep the car battery fully charged, the engine and battery warm, and use low viscosity synthetic engine oil. AGM or Ni-Cad batteries work better in sub-zero temperatures and wet lead-acid batteries.<br /><br /><br />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.
