
SMF Battery FAQs
VRLA stands for Valve Regulated Lead Acid. This type of technology covers both Gel batteries and AGM batteries. VRLA batteries are also called "recombinant" batteries.
During charge, oxygen is normally produced by the positive plate of a lead acid battery where it is carried up through the liquid electrolyte and out gassed. In a similar fashion hydrogen is released from the negative plate, and along with the oxygen loss results in an overall water loss from the battery.
In a VRLA battery, the oxygen migrates to the negative plate and is "recombined". This prevents hydrogen generation at the negative plate under normal charge conditions and water (H20) is produced instead. The recombining is accomplished by using pressure vents (valves) in the cover of the battery.
This is why a VRLA battery does not vent gases under normal operating conditions and never needs water. This is also why a VRLA battery should never be opened. Opening would add additional oxygen and cause an imbalance in the system. The pressure relief valve could also be damaged and result in future malfunctions. Opening a VRLA battery will void the warranty
Yes. The OKAYA VRLA batteries can be installed in any orientation except inverted position.
For VRLA batteries water top-up is not required. In case of flooded batteries, periodic top-up is to be done with battery grade (de-mineralized) water conforming to IS 1069.
A GEL battery is a VRLA battery that has an internal construction very similar to a traditional flooded lead acid battery. The difference is that a gelling agent is added to the electrolyte and pressure vents are added to the cover of the battery. GEL batteries can bring out gas early in life until the gel dries out and cracks form in the Gel to allow recombination. The gelled electrolyte can also flow which mean there are limitations in mounting orientations.
AGM stands for Absorbed Glass Mat. An AGM battery is a VRLA battery that has its entire amount of electrolyte "absorbed" in the separator material. The separator acts like a sponge and is saturated to approximately 98% (over 100% would mean free acid in the battery). This is why an AGM battery is spill-proof and can be mounted in virtually any position.
Both batteries are sealed and are part of the VRLA family. Gel batteries typically excel in extreme deep cycling applications. Gel batteries do not do particularly well in temperatures less than 32°F due to increased impedance from the Gel and are not appropriate for high power applications. Gel batteries also have a low recharge voltage that prohibits their use unless special charging regimes are followed (typical alternator voltage is too high).
AGM batteries have a lower internal resistance than Gel batteries allowing them to excel in high power and current applications. This lower resistance also gives the AGM battery a significant advantage in delivering its power in very cold temperatures.
A gel cell or gelled electrolyte is a sealed battery containing semi-solid electrolyte and may also be identified as a sealed lead acid, AGM (absorbed glass mat) or VRLA type battery. AGM batteries are sometimes referred to as starved electrolyte because the fiberglass mat contained within the cell is saturated only 95% with acid and there is no excess liquid. Nearly all AGM batteries are VRLA or valve regulated. VRLA batteries are designed with a valve that allows the battery to keep a slight positive pressure.
An AGM battery should have ventilation due to the chance of overcharging thus opening the pressure valves where gases can be expelled. This is a safety precaution that must be adhered to with all lead acid batteries. Moreover, vented areas are required for dissipation of heat which may be generated due to overcharging.
Over years of AGM products and experience in the market place in a wide variety of demanding applications. Some of the applications that use our AGM batteries are automotive, marine, motive power, telecommunications and network backup power to name a few.
The AGM is an acid starved battery that cannot be accessed. Because of the limited electrolyte in the battery special charging guidelines must be followed. If the battery is overcharged, off gassing will occur and the battery can prematurely fail from drying out.
The answer is also similar to why an AGM battery cycles better. The matting material along with compression technology provides a rock solid cell that dramatically improves vibration performance.
One reason is due to the matting material and how the battery is manufactured. The main failure mode from cycling is the paste wear out and shedding away from the grid. The matting material acts like re-bar in concrete and adds support to the paste. This support is enhanced by compressing the cell in manufacturing. Each cell in an AGM battery is compressed 25 - 30% before being inserted into the container. This combination allows the paste to last longer than in a flooded lead acid battery.
An AGM battery has no free electrolyte in the battery. All available acid is absorbed in the matting material.
If the battery was always operated under ideal conditions then the battery could be mounted in any position. But the possibility for overcharging the battery exists. When the battery is overcharged the pressure vents will open. Gases will escape the battery and can condense in certain ambient conditions to form acid. This acid would puddle up if the battery was mounted upside down.
