AGM battery capacity interpolation

Torleif

Hi,
First of all - a great forum!
I will install a battery monitor (Victron - BMV600) on my solar system. I have a couple of AGM batteries that are rated 200Ah(10h) and 290(100h). I need the 20h capacity for the monitor. The batteries are branded by a retailer here in Norway and it is imposible to get relevant information from them. Hence, I need to interpolate the capacity. Searching the internet it is clear that the discharge curve is not linear, and I see from looking at a number of AGM battery specs that the capacity ratio (20h/100h) varies considerably. Are there any suggestions out there?

Solar Guppy

Re: AGM battery capacity interpolation

Its about 15% better at a C20 rate than C10

So a C10 ~200ah rated battery would be ~230ah at C20

BB.

Re: AGM battery capacity interpolation

Smart Gauge's website has Peukert math information and even a couple spread sheet that you can download to calculate the 20 HR rate from other rates:

www.smartgauge.co.uk/peukert_chg.html
www.smartgauge.co.uk/peukert_depth.html

-Bill