I built out a solar/battery system for my travel trailer a few months back. I started with a single LifePO4 battery (CHINS 200Ah 12v). I purchased a Victron Blue Smart charger, and fully charged the single battery prior to installing it. I unfortunately do not recall if I actually tested the voltage after charging and before installing/wiring into the system. Using 4/0 wire for connections from battery to 400A fuse, distributor, shunt, and from the distributor to MultiPlus and ground, for what it's worth.
My plan all along was to add a second battery, and I have recently purchased one of the same model, identical specs etc. While I haven't actually taken the trailer out for a trip, I have tested the system to work for everything but hooking up to shore power - all AC and DC components working flawlessly. It even ran my A/C for several minutes in one go - I just to see if it would do it. It pulled a heck of a lot of power, but nothing tripped or alarmed, everything seemed to go just fine.
In order to properly add in the second battery, my idea was to pull out the existing battery and charge them both fully before wiring everything up in the trailer. What I'm finding though, is that while the new battery, after being hooked up to the Victron blue smart charger, fully charged and is sitting at 14.15v currently. The existing battery that I pulled from the trailer, however, doesn't seem to be able to fully charge. The charger started in bulk mode, reached Absorption, and just stays there. I've had it hooked up for several hours overnight and it's still not showing as completing the cycle. I turned off the charger and unhooked it, and the battery is reading 13.5v. If I hook the charger back up, it starts briefly pushing 15A (I have it set for "night mode" so it wont try to push 30A) and quickly goes to 0A at 14.2v and into absorption mode again. I'm not sure what to make of it. According to the Victron documentation for the blue smart charger, a full cycle, even for a depleted battery, should take no longer than 8 hours.
Any ideas as to if there might be a problem, and how would I go about proving/confirming it? Or should I just let this go indefinitely in absorption mode until...something happens?
edit - I don't think this should matter, but I wanted to mention that recently we've had some pretty cold weather, below freezing for a stretch of days. Nothing was ever connected to the battery during this time that would cause any draw or charge - solar is cut off when I'm not there and battery cutoff was in the off position. So the battery would have been exposed to freezing temps for a bit but not while in use or charging.
My plan all along was to add a second battery, and I have recently purchased one of the same model, identical specs etc. While I haven't actually taken the trailer out for a trip, I have tested the system to work for everything but hooking up to shore power - all AC and DC components working flawlessly. It even ran my A/C for several minutes in one go - I just to see if it would do it. It pulled a heck of a lot of power, but nothing tripped or alarmed, everything seemed to go just fine.
In order to properly add in the second battery, my idea was to pull out the existing battery and charge them both fully before wiring everything up in the trailer. What I'm finding though, is that while the new battery, after being hooked up to the Victron blue smart charger, fully charged and is sitting at 14.15v currently. The existing battery that I pulled from the trailer, however, doesn't seem to be able to fully charge. The charger started in bulk mode, reached Absorption, and just stays there. I've had it hooked up for several hours overnight and it's still not showing as completing the cycle. I turned off the charger and unhooked it, and the battery is reading 13.5v. If I hook the charger back up, it starts briefly pushing 15A (I have it set for "night mode" so it wont try to push 30A) and quickly goes to 0A at 14.2v and into absorption mode again. I'm not sure what to make of it. According to the Victron documentation for the blue smart charger, a full cycle, even for a depleted battery, should take no longer than 8 hours.
Any ideas as to if there might be a problem, and how would I go about proving/confirming it? Or should I just let this go indefinitely in absorption mode until...something happens?
edit - I don't think this should matter, but I wanted to mention that recently we've had some pretty cold weather, below freezing for a stretch of days. Nothing was ever connected to the battery during this time that would cause any draw or charge - solar is cut off when I'm not there and battery cutoff was in the off position. So the battery would have been exposed to freezing temps for a bit but not while in use or charging.
Last edited:
