Can AGM batteries be drawn down further than FLA without serious impact on longevity?

[john61ct]

not wrong but too general, huge variations from one model to the other within each grouping

[HighTemp]

Originally Posted by contrail

J
There is a lead acid AGM, named the Firefly, and which uses Carbon Foam construction, that can take a very deep discharge, but while often worth it, this still shortens the number of cycles it will endure. Importantly, however, it handles the partial state of charge side of the equation very well. But, it's about the only one that does.

I recently installed 5 Firefly AGM's in my boat. Firefly claims 3 to 4X the life at 50% DOD over standard AGM's, and that they can be drawn down to more than 80% DOD without damaging them. I have no plans to see if the latter is true, but so far, we are very happy with them. Time will tell, but with only a slight cost increase over standard AGM's, the claimed superiority in performance made them worth trying in my opinion. So far the only downside was the wait for them to become available. They can't seem to keep them in stock.

[john61ct]

Yes apparently unique in that regard

Resistance to PSOC abuse even more so

without going to LFP, that is a more thorough solution to both issues

but at a much higher cost