AGM batteries
AGM batteries last longest with the correct charging voltage. They also don't like to sit partially charged. Modern cars are programmed to reduce charging output from the alternator after about 90 seconds as a fuel saving measure. This does not help AGM's, which like to be charged at around 14.7 volts, if memory serves.
On my 2008 GMC 2500HD gas 6.0, I have two AGM's and a pretty heavy amp load for the stereo. I learned about this issue and found an interesting solution. It involves a Sterling Power DC Input Battery Charger, which charges the batteries at the level that's best suited for them.
https://www.sterling-power-usa.com/...probattc-batterytobatterycharger12vto12v.aspx
AGM batteries last longest with the correct charging voltage. They also don't like to sit partially charged. Modern cars are programmed to reduce charging output from the alternator after about 90 seconds as a fuel saving measure. This does not help AGM's, which like to be charged at around 14.7 volts, if memory serves.
On my 2008 GMC 2500HD gas 6.0, I have two AGM's and a pretty heavy amp load for the stereo. I learned about this issue and found an interesting solution. It involves a Sterling Power DC Input Battery Charger, which charges the batteries at the level that's best suited for them.
https://www.sterling-power-usa.com/...probattc-batterytobatterycharger12vto12v.aspx