| For years, I have been advocating the necessity | | | | without the need to recalibrate, or purchase |
| of battery backup sump pump systems for | | | | special chargers. There are no charge or discharge |
| homeowners serious about waterproofing their | | | | current limits. With AGM's low internal resistance, |
| basements. A backup system by itself, however, | | | | the buildup of heat is almost non-existent, during |
| is not the only necessary measure. Another | | | | normal and heavy charged and discharged |
| factor that may be just as important, if not more | | | | currents. Other gelled batteries have the potential |
| is the battery. The best backup system in the | | | | to lose capacity if overcharged due to voids |
| world may be completely useless if the actual | | | | developing in the gel. |
| battery is one of poor quality. | | | | With the AGM battery's low self-discharge of one |
| Deep-cycle, no-maintenance marine batteries are | | | | to three percent average per month, they are |
| the best designed battery for supplying DC | | | | able to be stored for a longer period of time |
| currents to battery backup sump pump systems. | | | | without charging versus other batteries. Even if |
| Most large rechargeable batteries are lead-acid | | | | discharged for more than 30 days, an AGM |
| type, as opposed to NiCads, which are generally | | | | battery can be recharged to almost full capacity. |
| more expensive. The acid in a lead-acid type | | | | Through electrolysis, AGM batteries preserve |
| marine battery will generally contain 30% sulfuric | | | | water as they charge. This is possible because of |
| acid at a full charge. Through my 22 plus years | | | | the recombining of hydrogen and oxygen, thus |
| experience as a supplier of battery backup sump | | | | converting to water while inside the battery. |
| pump systems to contractors around the United | | | | Water loss in other gelled batteries, especially in |
| States and Canada, the most effective battery is | | | | hotter climates, is quite common and often leads |
| AGM - Absorption Glass Mat. | | | | to the premature death of a battery after a few |
| Most typical gelled batteries contain the | | | | short years. With the AGM battery, water loss is |
| combination of acid and silica gel. AGM batteries | | | | not a problem, making it maintenance-free. |
| provide all the advantages that come with gelled | | | | Because of the mounted plates, acid will not leak |
| batteries. They do not, however, exhibit the | | | | or spill from AGM batteries. Because the plates |
| disadvantages of gel batteries. The acid in an | | | | are packed tightly, they can withstand shock and |
| AGM battery is contained by the fiberglass mat, | | | | vibration. AGM batteries are completely |
| and yet is still available for the battery's plates, | | | | non-hazardous, making them a more viable (and |
| resulting in faster migration of acid. This gives the | | | | cheaper) option for shipping. |
| battery a higher rate of delivery and absorption | | | | When considering the purchase of a battery |
| of amperage. Most typical gelled batteries must | | | | backup sump pump system, insisting that the |
| be charged at a slower rate to prevent cell | | | | pump uses an AGM battery would be the wisest |
| damage from excess gas. | | | | choice in order to maximize the effectiveness of |
| AGM batteries can be charged at normal voltages, | | | | the sump pump. |