Lithium batteries

[larsb]

I just got my trailer back from extended repairs at CW. I noticed that my batteries were only at 13.2 volts. I turned the solar switch off since my trailer is in a covered area. I did some checking and found that the battery switch was in the remove cover mode, probably done when CW was working on slides. Even though I turned battery switch back on my batteries continue to show 13.3 volts no higher. I would have thought they would have charged back up to 13.8 volts.

[jxnbbl]

Originally Posted by larsb

I just got my trailer back from extended repairs at CW. I noticed that my batteries were only at 13.2 volts. I turned the solar switch off since my trailer is in a covered area. I did some checking and found that the battery switch was in the remove cover mode, probably done when CW was working on slides. Even though I turned battery switch back on my batteries continue to show 13.3 volts no higher. I would have thought they would have charged back up to 13.8 volts.

Did you disconnect your batteries? I found out last year that depending on your solar controller the sequence has to be disconnect the panel positive, connect batteries, connect the panel positive. (or have switches). Although I thought my cover blocks all sunlight what was interesting enough sunlight gets through that the controller thinks the batteries are bad (they were disconnected for the winter) and it goes into some emergency mode shutting down. I now switch off the positive to the controller.

[larsb]

No I did nothing I was told by CW that I should just leave everything on since my trailer is plugged into power. Of course since it was at CW being repaired for 3 months. I know it wasn’t plugged in but the solar panels should have been working since it was outside. My batteries aren’t dead but the way I figure at 13.3 volts they are about 70% charged. I am just wondering why they won’t charge back to 100%.

[RacerX]

I would check the specs for your battery manufacturer. From the web:

“A 12v lithium LiFePO4 battery fully charged to 100% will hold voltage around 13.3-13.4v.”

This is consistent with what I see from my lithium batteries especially when connected to the rig.

[Stircrazy]

Originally Posted by RacerX

I would check the specs for your battery manufacturer. From the web:

“A 12v lithium LiFePO4 battery fully charged to 100% will hold voltage around 13.3-13.4v.”

This is consistent with what I see from my lithium batteries especially when connected to the rig.

13.6 is resting 100%, 13.4 is 90% and 13.3 is 80% for a LifePo4 12V battery

[Stircrazy]

Originally Posted by larsb

No I did nothing I was told by CW that I should just leave everything on since my trailer is plugged into power. Of course since it was at CW being repaired for 3 months. I know it wasn’t plugged in but the solar panels should have been working since it was outside. My batteries aren’t dead but the way I figure at 13.3 volts they are about 70% charged. I am just wondering why they won’t charge back to 100%.

have toy used a multimeter to see what the voltage is at on the terminals when everything is on? if it is only 13.3 then neither your solar or your converter is working properly, maybe the battery switch is turned off and the charging sources are tied in on the opposite side of the cut off switch? is their a breaker on your solar that would need to be reset? could guess things for days but there has to be trouble shooting to narrow things down. I would start going through the different systems starting with the easy obvious stuff first, like the battery cutoff switch..

Steve

[larsb]

I unplugged the power to my trailer today for a few minutes and the plug it back in and the batteries charged up to 13.7 and that’s where they have remained. So I guess I just needed to cycle the system. Thanks for all the replies.

[RacerX]

Originally Posted by Stircrazy

13.6 is resting 100%, 13.4 is 90% and 13.3 is 80% for a LifePo4 12V battery

No, your chart is out of date. resting 13.4 is 99% 13.3 is 90% with current lifep04 12 v at rest and not connected to anything. But it sounds like the OP got his result so all good. . Those specs are from the current Battleborn and LiTime charts

[Cheesehead4Life]

Glad to hear it seems to be fully charging now. I’m wondering if you have one of the WFCO autodetecting FLA vs Lithium converter chargers. They can take a few cycles for the lithium profile (higher charge voltage) to kick in. They probably have to re-learn each time you disconnect the battery because it wouldn’t know if you’ve simply used a disconnect switch, or attached a different battery.