First, let’s talk about the similarities in the two:
- Both are maintenance free, require no water to be added, and can be mounted in any position.
- Both use lead plates and similar chemistries for charging.
- Both are acceptable for unrestricted travel.
The differences start in manufacturing. Gel batteries have lead plated with traditional leaf separators between cells. Silicates are added to the liquid electrolyte allowing it to become gelled. AGM uses a process where the lead plates have a separator made from an absorbent glass mat (hence its name), permitting 100% of the electrolyte to be captivated and soaked into this material.
This AGM technology creates a dramatically improved cycle life and offers a lower cost per cycle for the end user. In fact, today’s better AGM batteries now nearly double the cycle life of Gel batteries. Also, the Gel battery normally takes 10-20 cycles of use before it starts to perform at its rated capacity, whereas the AGM reaches 95-100% capacity from the start.
The bottom line is this: High quality AGM batteries are cheaper to buy initially and last through more cycles (discharge and recharge) than comparable quality Gel cell batteries. Seems like a “no-brainer” to me!