crazy battery issues

[Sunking]

well, I've been trying to fix this issue for months. So, I have wired the batteries in series.. The results however were not good, dead batteries every morning. I'm sure that is due to bad cells, but thats why I've switched it back. Sounds like he sold me batteries he shouldn't have. I'm not happy about that.

Real simple, the batteries are done, stick a fork in them. There is nothing you can do with them. You cannot fix dead.

The batteries were never made to be cycled to begin with. They are Stationary Batteries made for a UPS.

So you claim to have a 2300 watt 24 volt system. Again the wrong voltage for that much power because it would require 2 Controllers for that much power. It needs to be 48 volts with a 45 amp minimum MPPT Controller. The batteries should be 6-volt batteries with a capacity of 450 to 500 AH wired in series is how you fix it. Otherwise you at just wasting time and money.

[douglasjett]

OK, new batteries it is... I might be stuck with 12v down here as 6v are just as much per battery. My last dumb question is this. If any of these UPS batteries will hold a charge is there a way to wire them in the bank so they will not compromise the new ones?? Thanks in advance.

[Sunking]

OK, new batteries it is... I might be stuck with 12v down here as 6v are just as much per battery. My last dumb question is this. If any of these UPS batteries will hold a charge is there a way to wire them in the bank so they will not compromise the new ones?? Thanks in advance.

No get rid of them. You cannot mix old with new batteries, or batteries of different capacities. Do not parallel batteries or you wil be right where you are right now in a short period of time. Larger batteries are less expensive than smaller batteries $/watthour.

Here is how you compare price. Take the battery voltage x amp hours = watt hours. Example 6 volts x 200 AH = 1200 watt hours, or 12 volts x 100 AH = 1200 watt hours. The 6-volt cost $150, and the 12 volt cost $160.

6 volt = $150 / 1200 wh = $.125 per watt hour
12 volt = $160 / 1200 wh = $.133 per watt hour

Using two 6 volts wired in series cost $300, and using two 12 volts in parallel cost $320 as an example. So calculate based on Watt Hours. Even if the 6 volt cost more is still less expensive in the long run because it will last 2 time longer than 12 volt batteries wired in parallel.

[Brian53713]

The one thing dead batteries are good for, is the $10 core charge that you might save by bringing them with when you get some new ones. After you confront that person about the faulty system problems.

[jflorey2]

OK, new batteries it is... I might be stuck with 12v down here as 6v are just as much per battery. My last dumb question is this. If any of these UPS batteries will hold a charge is there a way to wire them in the bank so they will not compromise the new ones??

Don't wire them into the same bank. If you can get money for the core, do that.

If you can't get rid of them, you could float them at 13.8V with a separate charger and connect them to the new bank ONLY when you are discharging. That will minimize their 'bad' effects on the new battery. Use a high current switch rated for battery switching service.

[douglasjett]

To all of those that have posted. I removed the batteries from the box they were in to discover that 3 of them had gotten so hot that they actually split out the side!! I'm running now on 6 of the old batteries and I have enough juice to get me through the night. I'm going to replace the entire bank soon. I have a couple of questions. First, regarding the MPPT CC do the $80 ones you find online work? Second, I'm well aware now that I should wire the batteries in Series but I am on limited funds. So, can I wire some of batteries in Parallel using smartguage suggestion?