New drain issue.

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Another source of drain could be If your new power ports are "always on". A USB port I connected uses .1Ah when powered (not when charging something). This is 2.4Ah per day which can make a difference and if you have two that could be 4.8Ah per day.
Hi, really like the battery charging station box. Neat. I love pressure cookers too but got one for use one on a gas stove. Just made beef sharwama in mine this evening. Delish.

Some MPPTs are fairly sophisticated and programmable, mine has an adjustable absorbtion and a float phase duration and voltages. The absorbtion phase is normally only for an hour. So a standard float for 12v at 13.8v might mean the controller is working as designed?

Sounds like the battery is wearing down and the inverter wiring needs upgrading as mentioned by others
My 2¢:
You need a minimum of 14.6V at the battery terminals to fully charge 12V Li batteries. Any less and the battery isn't getting fully charged. Your charge controller should be adjustable.

If you don't have a coulomb counter get one. If you have one use it to learn your usage. I spent a lot of time the first year watching my usage. Learn how much your laptop uses under normal usage. Learn how much your refrigerator uses at different outside temps. Same with all other draws on your battery. A decent coulomb counter should give you daily solar input and usage totals.

You will probably have to use shore power to get your battery back to 100% if you don't want to shut all draws down. Then your learning will tell you if you have enough battery. 300W solar should be enough, but you need to measure it.

I have more power draws than you with 200W solar and 210AH FLA batteries. I am back usually back to 100% before noon and can go an extra day without sun before I need to look for alternative charging. My two big draws are refrigerator and cell booster.
The magic of solar and storage does have it's internal gremlins. Didn't realise Time Ampere is a brand of LiFePo4 battery.

The BMS could be doing something strange in there. Not knowing anything about it, if it's constantly trying to balance a bad cell or set of cells it will be draining the healthy ones.

But the main thing I've found after sitting and watching voltage rise from the different types of battery chemistries is Li based systems don't ever like to go near their maximum volts. Pb tech loves it. Ni not as much, Li never from my experience. You can watch the voltage rise on LiFePo4 at the end of it's charge voltage and it will just keep going up without some way of artifically stopping it :(. The beauty of Pb tech is the internal resistance will keep rising to match the full battery state.

I've used the major battery types and NiFe and NiMh are my favorite. I keep my homemade 24v LiPo with a close eye on it. 40-80% SoC. Individual cell monitoring with BMS. I tried LiFe but wasn't convinced it would work for me.

I've probably wasted a lot of time watching voltage go up from solar. It is magical.
This is what my refrigerator heat exchanger looked like after2 years. Cleaning it reduced my power consumption noticeably.


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Just so everyone knows, I switched out a burnt wire that was going to the inverter with a thicker gauge one and the drain has pretty much disappeared at this point.

So it appears the problem was the burnt inverter wire. I waited a bit to make sure, but the problem appears to be fixed now.

I also purchased a 2nd battery (haven't hooked it up yet) and some thick cables (which came with lugs and heat shrink) to connect the two batteries with.