What?s the difference between a Sealed Lead Acid battery, a Gel Cell Battery, an Absorbed Electrolyte Battery, a Valve Regulated Battery, and why does it matter?
These are many different types of Lead-Acid rechargeable battery, and there is some confusion. Quite often customers refer to a battery as a “Gel Cell”, when in fact it’s another type of SLA battery. There is not much difference in discharge performance, but there is often a difference in recharge voltage limit. Sealed Lead Acid is a generic term for all lead acid batteries which have fixed tops, so the electrolyte is supplied with the battery when it?s manufactured, and it’s not intended that the battery ever be opened or topped up in the field. These are also sometimes known as “maintainance free” batteries. Sealed Lead Acid (SLA) has become a popular generic term, and is widely used in the industry. It’s actually a rather misleading term, since all lead acid batteries must have vents to allow any excess gas pressure to escape from the battery casing, especially if cells become overcharged under fault conditions such as a shorted cell. Lead acid batteries should, in general, never be
