AGM battery analysis ?

[Larry DeCamp]

There appears to be concensus that a small AGM battery is the least complicated and most cost effective option for E dependant Ignitioin & FI backup. How should you confirm battery fitness for defined service/mission ? Some suggest HF battery tester, some say drain the battery to 10 volts with a light bulb load and measure time. Is there a device or routinely administered protocol to know if battery #2 is fit for the mission ?

[rv6ejguy]

I do an annual load test on my backup AGM. 10.5 amps draw (for EFI and EI) and measure the time it takes to go to 9V under that load.

Powersonic publishes various time vs. discharge rates to 9V. This assumes a fresh health battery. They also publish shelf lives without charging and capacity vs. number of discharge cycles, shelf life etc.

Click on any PDF here for full specs: http://www.power-sonic.com/ps_psg_series.php