Translations:Lead acid battery/13/en

In the 1970's valve-regulated lead acid batteries began to enter the market. These batteries solved many of the major faults with flooded lead acid batteries: they are maintenance-free, they do not have a liquid acid electrolyte that can be spilled, and they do not expel significant amoutns of hydrogen. There are trade-offs though: they are less durable because they are not as tolerant of deep discharges, they have a shorter cycle life and they cost significantly more than flooded lead acid batteries. There are two primary sub-categories of VRLA batteries: Absorption glass mat (AGM) and Gel.