AGM Battery - normal discharge rate

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Originally Posted by jordanbigel

I had a conversation with a neighbor this morning, he's ex-navy, getting a boat ready to cruise, he seems pretty smart. But, the subject came up of power usage and charging, and he stated that his new AGM batteries could be routinely discharged down to 20% charge (80% discharge) without harm. I told him I didn't think that was right, and maybe they could do that once or twice without affecting longevity, but if you do that regularly while cruising you will kill your batteries pretty quickly (2-3 years I would guess).

And I see a lot of battery sales-seak online claiming the DoD is 80%, I read at least one "article" claiming that you can go down 80% because you end up with fewer charging cycles - I don't buy that. My understanding was that the strength of AGM batteries is faster acceptance rate when charging, and higher max discharge amps (ability to draw more power faster) - but any LA battery will suffer if discharged to 80% routinely, right? Or not?

everything depend how battery cell plate made. if a battery plate made high pressure hadi casting like Exide C10 Torr Tubular made in India this your friend scenario is possible.

?-how to know is battery plate made high-pressure hadi casting.
A- Easy, 5-7 year warranty on battery.

Warranty tell everything how is a lead battery made 1-2 year warranty gravity casting
2-4 y low pressure casting
5-10 y hadi high pressure (except India made with Exide battery and some other India battery) usually military battery.

Hadi is German manufacture company who made high pressure casting machine and process

[Lusea1]

Originally Posted by jordanbigel

I had a conversation with a neighbor this morning, he's ex-navy, getting a boat ready to cruise, he seems pretty smart. But, the subject came up of power usage and charging, and he stated that his new AGM batteries could be routinely discharged down to 20% charge (80% discharge) without harm. I told him I didn't think that was right, and maybe they could do that once or twice without affecting longevity, but if you do that regularly while cruising you will kill your batteries pretty quickly (2-3 years I would guess).

And I see a lot of battery sales-seak online claiming the DoD is 80%, I read at least one "article" claiming that you can go down 80% because you end up with fewer charging cycles - I don't buy that. My understanding was that the strength of AGM batteries is faster acceptance rate when charging, and higher max discharge amps (ability to draw more power faster) - but any LA battery will suffer if discharged to 80% routinely, right? Or not?

Yes, you are right!