Dead batteries

[Tap22a]

Hey everybody. New to travel trailer ownership here. Winterized my trailer this season and covered it, covering the solar panel. I forgot about the batteries and now they're completely dead. Can I uncover the trailer and let the solar panel recharge them? Do I need to disconnect them and hook em up to a charger? Or are they beyond saving and need to be replaced? Please help!

 

[flybouy]

If they are fla batteries and totally discharged then they will be damaged. You can try to charge them and seeing they hold a charge but if they do they likely will not charge up to 100%. How old are your batteries and what type are they? It would be helpful in answering questions if you create a signature with year and full model of the trailer and tow vehichle.

 

[NH_Bulldog]

If you have lead-acid batteries, there are two issues you will experience with discharge. First is that a lead-acid battery cannot be discharged to less than 50% without potentially catastrophic internal failure, and second is that a discharged lead-acid battery that is also subjected to freezing temperatures will finish it off for good. If you have lithium batteries, you are likely safe since they can be discharged to zero and they can handle subzero temperatures without harm.

A few ideas to prevent this in the future: When I winterize, I turn off the solar disconnect, turn off the battery disconnect, and remove the batteries to my workshop where I keep them warm and monitor the state of charge. For LiFePO4 batteries, they stay at 13.2v all winter which is an ideal 70% state of charge for long term (5 month) storage. You may also consider keeping the trailer plugged in to a shore power source to let the converter charge the batteries if you have power available. That has two caveats; A fully charged and maintained lead-acid battery can be subjected to freezing temps, but a lithium battery cannot be safely charged or discharged at temperatures below freezing.

If you have lead-acid batteries, you should remove and charge them and then take to an auto parts shop and have them load-tested (typically for free).