Batteries used in things like wheel chairs are essential for every day living and it is not convenient when they die. When you depend on a battery for mobility, it is crucial that the battery is a powerful one.
Batteries designed specifically for electric motors are known as traction batteries. They are constructed is several ways. One is a gel-battery in which electrolyte gel packs are used to avoid spilling common in lead-acid batteries. A newer traction battery on the market is the AGM battery, or absorbed glass mat battery. In this battery, the electrolyte is embedded in between boron-silicate glass mats. Just like gel-batteries they will not spill if broken, but AGM batteries can take much more mechanical abuse from things like shock and vibration.
AGM wheelchair batteries are also more ideal because of their charge and discharge rates. Charging an AGM battery is similar to most standard batteries, so there is no need for a special charger, and there are no problems with incompatible chargers. AGM batteries have a very low self-discharge rate which allows them to sit for periods of time without recharging. AGM batteries also charge quite rapidly.
AGM batteries are a great and safe alternative to the hazardous lead-acid batteries. In cases of mobility, spillage can be a deadly issue. Wheelchair batteries can be quite expensive, but they are long lasting and crucial for those who need them to get around.