What is a Starting battery?
Starting batteries (sometimes called SLI, for starting, lighting, ignition) are commonly used to start and run engines. Engine starters need a very large starting current for a very short time. Starting batteries have a large number of thin plates for maximum surface area. The plates are composed of a Lead "sponge", similar in appearance to a very fine foam sponge. This gives a very large surface area, but if deep cycled, this sponge will quickly be consumed and fall to the bottom of the cells. Automotive batteries will generally fail after 30-150 deep cycles if deep cycled, while they may last for thousands of cycles in normal starting use (2-5% discharger).
What are the advantages of the AGM battery?
The advantages of AGM batteries are no maintenance, sealed against fumes, hydrogen, leakage, or non-spilling even if they are broken, and can survive most freezes. AGM batteries are "recombinant" which means the Oxygen and Hydrogen recombines inside the battery. These use gas phase transfer of oxygen to the negative plates to recombine them back into water while charging and prevent the loss of water through electrolysis. The recombining is typically 99+% efficient, so almost no water is lost. Charging voltages for most AGM batteries are the same as for a standard type battery so there is no need for special charging adjustments or problems with incompatible chargers or charger controls. Since the internal resistance is extremely low, there is almost no heating of the battery even under heavy charger and discharger currents. AGM batteries have a very low self-discharger rate (from 1% to 3% per month). So they can sit in storage for much longer periods without charging. The plates in AGM's are tightly packed and rigidly mounted, and will withstand shock and vibration better than any standard battery.
What is an OHM?
OHM is a unit for measuring electrical resistance or impedance within an electrical circuit.
Can batteries freeze?
In a partially discharged state, the electrolyte in a lead acid battery may freeze. At a 40% state of charger, electrolyte will freeze if the temperature reaches approximately ?6.0°F. The freezing temperature of the electrolyte in a fully charged battery is -92.0°F.
