Fix-It: How to perform Battery Maintenance on Bluetti AC300/AC500 system. Recalibrate batteries. 

Thanks for this video. I bought my son an AC300/B300 combo several months ago and wasn't sure exactly how to cycle discharge the B300. We will be recharging using the AC300, but it was moment the battery hit 0% that I was unsure about what happens. Now I know it will drop the load and we should then plug in the AC300 to the grid. Thanks for the guidance.

Great video! My AC200MAX dropped from 95% to 0% in no time, I didn't even noticed, under small load of phone and power bank charging. I was so surprised and shocked! I think this is after days of charging it with unreliable solar (winter time now in Europe) and discharging with AC load (dehumidifier) as well as other light usage. I own the unit for about half a year, and have two B300 extensions in the mix. The BMS must have got confused and lost track of the correct state of charge. I need to recalibrate the whole stack, but will wait for the second T500, since I have no grid and will run it on inverter generator. I think the manual recommends to discharge the unit completely every 3 or 6 months.

Thanks for posting this. We are in the relative infancy of this technology, at least on a widespread basis. Great reminder, that we need to understand this, especially given what we paid for the equipment, and keep up with our maintenance. Bluetti should be paying you.

Does the T500 work with the B300S? in their website doesn't mention the AC500/B300S on the T500 spec compatibility.

Thank you for your excellent and detailed videos. They have been very helpful. Unfortunately, I must be missing something when it comes to my Bluetti AC200Max system. I've tried recalibrating my AC200Max connected to a single B230 several times but have always discharged and recharged them connected because I don't have a second T500 charger and I didn't want to leave one of the batteries in a depleted state long enough to fully charge one battery and then start charging the other battery. In my case, the AC200Max and B230 are connected throughout the process. I run them both to 0 until they shut themselves down, then recharge using the T500. I've tried recharging with the AC charger connected to the AC200Max sometimes and other times via the B230 but neither approach has worked for me. Both batteries do charge to a full 100% but when I start using them again, the SOCs start diverging more and more so they get up to 30-35% difference in SOCs (e.g. B1=65% and B2=32%. Then they start converging again as they approach zero. At several different charge levels, I've looked at the voltages on the individual cells and they are almost always identical - only differing by 0.01 volts usually (e.g. 3.22 v versus 3.23 v on B1 versus B2). It's very annoying. In your experience, what do you think is happening here? Do I need to do the calibration on each battery separately and disconnected? The B230 has its own BMS but I'm not sure how the two BMS's work together. I was assuming the BMS on the AC200Max was the master one trying to balance out the charge on both batteries. I have BMS v1017.04 on the main unit and v 1011.09 on the B230. Any help would be appreciated. Thanks again for your videos.

I got a ac 200 max question. If i am charging my b300 battery itself(through its chsrgijg port) will it trickle down and charge the head unit(ac200max?)

Wondering if two batteries direct into vs daisy chained batteries plays any part of sync gap issues

It looks like Bluetti's firmware got smarter. I just added a 6th and final battery to my AC500 and it came with a 65% charge. The other five had reached 100% earlier in the day. I watched the app where it shows the individual batteries and the other 5 batteries went into standby mode while the new battery is in charge mode and is almost caught up. So it looks like I won't have to do another calibration (the last one was with 3 batteries.)

I have an AC200P that has been sitting at low charge for months (was stored with 100% charge then forgotten about). The screen still turns on for about 60 seconds if I try to turn it on. If I try and feed it with the AC mains charger the charger won't recognise the unit and so won't dump any current down the cable. My question, is that if I connect it to a 200W solar panel to try and force some charge back into the cells, what is the risk of the unit causing a fire? You seem to know all about this brand, I wondered if you think their safety measures are good enough for me to try and recover this unit, or if I should give up before I burn down my toolshed? 😂 Any and all advice would be appreciated! All the best :)

Does the T500 actually charge your batteries once low voltage protection kicks in? The T400 I have and 12V via XT-90 both seem to do absolutely nothing for my drained B300. I haven't seen a good teardown to find out what's actually going on internally, not sure how the BMS might be interfering with charging.

Excellent video! Thank you

I have a question since I don't have the grid why don't you just use solar panels. Hook up battery individually I would think that would still work.

Do you have an emergency shutdown?

I thought power stations did need any mainetance. This quite a surprise.

All the while I thought Bluetti power stations did not need maintenance, guess it is another surprise aside from the endless problems they have.

You shouldn't have to do that with technology now. These units are way to expensive to need to fix them

And you said you had a big batteries bank I see two units with 2 batteries each that's not a big batteries. You sead big battery back you should have for berries for each generator and then you could say big battery Bank.