by noseoil » Sun Feb 07, 2016 10:24 am
Brian, not sure where you were looking, but I'm not seeing this type of result in my looks online. The AGM batteries do cost more, but it sounds like you got a "salesman" and not someone who knows the technology & systems in general. It sounds like you're getting frustrated with your search, so here's my take on things based on what you've found. (Note: IMHO, the typical salesman is a cross between a used car salesman & Hannibal Lecter, from Silence of the Lambs. After the sale you take the money, eat the customer's liver & have no remorse).
Two of the biggest problems people have with any electrical system is with the initial design & ongoing maintenance issues. Many people don't check fluid levels in a flooded battery. They don't monitor state of charge & leave the battery to sit for too long. They won't check cable ends for corrosion or look at things regularly to make sure things are still good. This makes for a short battery life, so the battery gets blamed for the problem. Shoot the messenger.
Again, just in my opinion, the initial design should include these things to work properly:
1 - Good battery location for service, maintenance, & replacement when necessary. If the battery is buried in the design, it's too hard to check & service.
2 - Loads on the battery are properly calculated for duration & a reserve capacity is built into the system. Not discharging the battery too deeply or too often will give the battery a much longer life.
3 - Charging rate should keep up with the loads, so the battery isn't cycled too deeply each time or allowed to stay discharged for long periods of time.
The best battery in the world will not last in a badly designed system. A cheap battery which is used in a well balanced system will last a long time, good bang for the bucks. A very good battery used in a very well designed system will last a long time. Just my $.02 worth.