There are other batteries called Green Cell AGM, which are 6 volts and are made of quality materials. AGM-based accumulator, what does this definition mean? The electrolyte is absorbed by a fiberglass separator and largely prevents leakage, and with this method the device can work in different positions and not just vertically. Absorbed Glass Mat is a special type of lead acid battery. OPTIMA batteries are considered as SPIRALCELL AGM batteries.