State of charge vs voltage on AGM SLA?

[Handlobraesing]

From my experience, they don't follow the same voltage pattern as regular car batteries and they vary between brands/types.

I have a pair of 12V 12Ah battery by Universal Power and these reads around 13.2 to 13.3v fully charged, days after full charge.

On the other hand, 12v 7Ah by Sunnyway battery, SW1270, the OEM battery in Power On Board HID light is 12.7 to 12.8v fully charged after a few days.

 

[wptski]

AGM's have a lower self discharge rate. I have a Jump n Start or whatever in my truck that has a AGM and only needs to topped off maybe once a year. I use a ADC float/charger that can be used on AGM's it normally doesn't take that much to top it off. I've never used it yet!