48v flooded led acid battery lower max charge voltage good or bad?

[fabieville]

I see on the internet where most manufacturers recommend a max charge voltage or absorption voltage of 57.6v-58.8v for flooded led acid battery. I have a nova 48v 3000watt 110vac pure sinewave inverter that allows a max of 57.1v input voltage. Because of this i cannot set my charge controller to 57.6v-58.8v according to what most manufacturers said you should charge a 48v flooded led acid battery to.

If I set the charge controller to cut off at 57v or 57.1v which it will go in the absorption stage at that voltage and then afterwards it will cut down to a float charge voltage of around 54v will I still be able to fully charge the flooded led acid battery? Is there any pros and cons with charging the 48v battery bank at a lower voltage setting than the recommended charge voltage which is 57.6v to 58.8v?

Is charging at the lower voltage setting increase my charging time to fully charge the battery?
is charging at a slightly lower voltage better for the battery?

[Sunking]

You will shorten the life of your battery period. Which means frequent replacement.

[fabieville]

If adjusting my input voltage max for my inverter is not possible. If I charge the battery bank to 57.1v on a daily basis but every once per week or once per 2 week or once per month i disconnect or turn off the inverter and give the battery a equalize charge up to 60v or a higher voltage charge of 58.8v until it is fully charge before connecting back the inverter would this reverse or prevent the limitation stated above?

If it would what full charge routine at 58.8v or equalize cycle at 60V or higher would be best to use, once per week? once per 2 week or once per month?

[Mike90250]

The lower the Bulk Charge Voltage, the Longer you have to hold it in the Absorption phase of charging. With solar, you run out of daylight before you reach full charge, After 48 or so hours, the crystals harden in the battery and you irreversibly loose capacity. So you need to do a "Boost Charge" every 48 hours.

[fabieville]

If I use the same low voltage of 57.1v for the cutoff voltage for the charge controller and the battery starts to charge going through the normal stages: bulk, absorb and then reaches a point where the float charge current is now charging at 1% of the battery bank amps capacity, would this suggest that the battery bank is completely charge? And in that case would the SG of the cells always be in the full charge stage/normal level whenever the charging stops and the battery comes to the rest voltage?

Would this prevent electrolyte from stratifying once the battery SG reading is showing normal level for all the cells when you check them at the rest voltage?
Would you still need to equalize the battery bank even thou the battery bank has got a full charge at least once in less than one week? or in less than 2 weeks?
Would you still get maximum capacity and avoid sulfation on the negative plate once you manage to get full charge for the battery at this low voltage setting?
Would you manage to get full charge for the battery at the same low voltage below room temp once you have high amps kicking into the battery most of the time from an oversize solar array?

Therefore if you oversize on you solar array so that you can get full charge and get the SG readings for the cells in the normal level most of the times then these limitations would not occur charging at the low voltage setting all the time
"Slow charge time; capacity readings may be inconsistent and declining with each cycle. Sulfation may occur without equalizing charge"

Am I correct?

Is there a way to disable the OVP on the inverter instead of adjusting it?

[Mike90250]

1) It's the OVP. Disable it and you cook the inverter

2) gassing bubbles during charge stir the electrolyte and inhibit stratifaction

3) hydrometer is only way to detect full charge. Not all cells in a battery are identical or will charge at the same rate, so a little bit of overcharge to prevent the laggards from sulfating is desired. But not too much ! Addition of water is your other gauge, if you are not needing to add much makeup water, you are NOT charging enough. If you are adding lots and lots, you are charging TOO much, If one cell out of all of them is "different" you have a problem with it.

I'm not going to go into 1% means you are good, because it's not what the battery mfgs state, you want about 10% charge rate in cycle use, and something much less for Float use,

If you have bought incompatible gear, maybe it can be exchanged.

Many of the other questions are answered at Battery University.

http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery

[fabieville]

If I disable the ovp I don't think the inverter will fry. The Labelling and the specs shows that it can
Handle 42-60v input. I am just wondering if is the manufacturer limit it to 57.1v. The voltage during charging won't pass 58.8v. The charge controller will limit it from going any further. So is there a way to disable the ovp instead of adjusting it?

[fabieville]

If i place a Battery Desulfator Circuit on the battery bank will that prevent sulfation from occuring charging the battery bank to only 57.1v at all times and not performing any equalizing?

Or suppose I place the battery desulfator circuiut on the battery bank and I equalize every once a month will this method give me back my full capacity ready every once a month and prevent long term sulfation from occuring on the battery bank due to the fact the the desulfator circuit is always connected and doing this routine will allow me to get the full life span out my battery bank?

[Mike90250]

Maybe, maybe not. Desulfators sometimes interfere with MPPT charge controllers, with their voltage pulses.

But I highly doubt they will allow you to chronically undercharge a battery and not sustain damage,

[sensij]

The spec sheet I'm looking at for a 48 V, 3000 W, Nova inverter shows 61.2 V as the voltage cutoff. What specific model are you using?

https://www.novaelectric.com/pdf/CGL-Series-3KW.pdf