Faq's

Basically there are two types of batteries, starting (cranking), and deep cycle (marine/golf cart/Fork-lift trucks). The starting battery (SLI starting lights ignition) is designed to deliver quick bursts of energy (such as starting engines) and have a greater plate count. The plates will also be thinner. The deep cycle battery has less instant energy but greater long-term energy delivery. Deep cycle batteries have thicker plates and can survive a number of discharge cycles.
Battery capacity (how many amp-hours it can hold) is reduced as temperature goes down, and increased as temperature goes up. The standard rating for batteries is at room temperature 25 degrees C. Battery charging voltage also changes with temperature.
Self discharge of plates and premature capacity loss; excessive float charge current and improper polarization of plates; shorts through separator, mossing or dendrite growth; overcharging of battery from high current and subsequent excessive gassing; excessive heat and loss of water; antimony transfer; low cold cranking performance; poor charge acceptance; inadequate high rate discharge performance.
A lead-acid battery is composed of a series of plates immerse in a solution of sulphuric acid. Each plate consists of a grid upon which is attached the active material (lead dioxide on the negative plates, pure lead on the positive plates.) All of the negative plates are connected together, as are all of the positive plates. When the battery is discharged (when it is subjected to an electrical load), acid from the electrolyte combines with the active plate material. This releases energy and converts the plate material to lead sulfate. The chemical reaction between constituent parts of the electrolyte and the spongy lead of the negative plates and The lead dioxide at the positive plates turns the surface of both plates into lead sulphate. As this process occurs the hydrogen within the acid reacts with the oxygen within the lead dioxide to form water. The net result of all this reaction is that the positive plate gives up electrons and the negative plate gains them in equal numbers, thereby creating a potential difference between the two plates. The duration of the reactions producing the cell voltage is limited if there is no connection between the two plates and the voltage will remain constant.
The capacity of a battery to store charge is often expressed in ampere hours (1 Ah = 3600 coulombs). If a battery can provide one ampere (1 A) of current (flow) for one hour, it has a real-world capacity of 1 Ah. If it can provide 1 A for 100 hours, its capacity is 100 Ah. Battery manufacturers use a standard method to determine how to rate their batteries. The battery is discharged at a constant rate of current over a fixed period of time, such as 10 hours or 20 hours, down to a set terminal voltage per cell. So a 100 ampere-hour battery is rated to provide 5 A for 20 hours at room temperature. The efficiency of a battery is different at different discharge rates.
Rechargeable batteries can be re-charged after they have been drained. This is done by applying externally supplied electrical current, which causes the chemical changes that occur in use to be reversed. Devices to supply the appropriate current are called chargers or recharges.