Its plugged in full time when not in use, so they should get a full charge no problem. And yes it's at the voltage spec for the batteries.Sounds like they are done. Did you charge until the return current dropped to 5A? At 14.4V or whatever the batteries spec is? It can take 48 hours if the batteries are badly sulfated, the current will drop, but then start climbing again, before tapering down to 5A
What charger are you using? Don't assume the "generic" profiles are doing what you need. Especially as the batteries age, they need progressively longer charge times, especially when cold. This is where the victrons full charge trigger can be set to return current AND voltage, as opposed to voltage and the AH counter being reset to zero.
Also note that many chargers temp compensation maxes out around 15V. When very cold the batteries may need higher, but it gets capped at the chargers max.
The gauge is super wonky..
Do you have it bluetoothed to the app? The app gives a ton more detailed data and easier to decipher whats going on
Yes agreed. And it seems mine is only good for ~250ah to 100% depleted.You "had" 500ah...but capacity goes down as they age. The shunt-type amp counter doesn't know the actual capacity, it only knows what you tell it, so it gets further and further off as time goes by.
To make it right, have to do a capacity test to determine the actual capacity then put that number into the amp counter.
The SmartGauge algorithmic battery monitor measures voltage and resistance and plots it on a curve to get state of charge. Unlike a shunt-type which gets more inaccurate over time, algorithmics get more accurate over time.
Balmar has combined the two to create a self-correcting shunt-type:
SG200 Battery Monitor - Balmar
SG200 Battery Monitor Balmar’s Expandable, Next Generation Monitor Learns & Displays All Critical Battery Parameters State of Charge (SoC%) State of Health (SoH%) Charge/Discharge Current Flow Time Remaining History, Faults & Alerts Support for All Common Battery Chemistries & Voltages Including...www.balmar.net
Before you spend more money on batteries, you may consider a more programmable charger. If you have a programmable solar charger, you could always get a 120V to ~19VDC power supply. Then connect that to the solar charger when on shore power. A good long absorb after days of winter camping is necessary for battery longevity. In some cases I have seen it take 24 hours to reach the 1% return rate on my 500AH AGM bank, after a 10 days of partial cycling.
You should also have a battery temp probe as you need more power when the battery is cold. Those Tripp Lite inverter/chargers will never put out enough to keep you even close to fully charged on shore power. I am going to by pass mine with a solar setup and go straight to the house battery. When it freaking warms up.
The charger part of the TL lets you select the battery type for charging and they have pre-determined those charging voltages and at least on mine, you cannot tweak that. The AGM setting on mine keeps it at a constant 13.8 but according to the battery manufacturer it needs to be more. Look for an inverter/charger that you can adjust that per the battery maker's spec and not the inverter company's interpretation of what they think it should be. A constantly undercharged battery will go bad faster.