After purchasing the AC500 with 1 B300S battery, when I started to use it I noticed that the battery would go from around 40% to 0% very quickly after the unit has been on for a couple of days.
I further investigated this by removing all load from the unit, but keeping the AC on to see if it was caused by a surge in one of my appliances. After running like this overnight the same thing happened. The battery lost all its charge very quickly, with no reason or load on the system.
Having looked on these forums, I see something similar being reported across different models with the proposed solution being to fully charge and discharge the unit twice to calibrate the battery. The first time I did this, the unit went from 39% to 0% in 4 mins (I managed to witness it happening) and the second discharge took it from 48% to 0% in 5 mins.
There’s definitely a problem with my unit, can you help please?
@Rich1 054 can be cleared when SOC＞5%. The firmware version is the latest. When the SOC reaches 0%, please try to charge it with an AC cable without interruption. If the charge and discharge cycles do not work, you can contact the after-sale service for a replacement.
@BLUETTI Yes I’ve already tried charging without interruption using the AC cable then discharging, so I need a replacement. Please tell me who to contact to get this resolved.
@BLUETTI It was bought on Indiegogo, contribution number 5448.
Please note that I’ve already emailed crowdfunding@bluetti.com multiple times over the last 3 weeks without response, so if you’re going to suggest that to me, please don’t. I need a contact that will actually respond and help me please. Are you able to contact them internally within Bluetti to look at my problems for me?
Was this issue ever resolved and do you know what happened with your unit? I am experiencing a similar situation with my AC500 unit. My unit was powering a small load (approximately 100 to 200 watts) this morning on a single B300s and the SOC was reading about 47%. When I checked on it about 5 minutes later, the SOC read 1% and then dropped to 0% and threw the alarm for bat depleted. I am recharging with AC right now as I was hoping this might be an SOC calibration issue but we will see if I get similar results. Mine is one of the first units as I got in on the early bird special but I never really let this battery get much below 50% before. I have 2 B300s batteries and have had issues with this one in the past charging to 99% and then continuing to charge for long periods of time but never reaching 100%. The other battery I got does not seem to experience this issue as it will reach 100% SOC. I am wondering if there is a problem with this particular battery. Thanks for any updates as it may help me troubleshoot my issue.
@Pilotstt Looking forward to the SOC calibration results. For the problem that the battery charge never reaches 100%, what charging method are you using? It is recommended that you try multiple charging methods to see if the results are the same.
I have some additional questions now. Using a load, I ran a B300s battery down until it emptied the battery and shut the AC500 unit down (in an attempt to recalibrate the SOC). I then charged the battery by itself to 1% with the cigarette lighter cable (to wake it up) followed by charging at a constant 7 amp rate from the AC cable. Everything seemed to be on track until the battery got into the 80% range and then I walked away from the unit for a while and when I got back a short time later, the unit had an error stating something about Battery Voltage High. When I cleared the error, the unit almost immediately went to 100% charge. I did some digging and found that this might be due to a firmware problem and I did not have the most recent firmware that was pushed so I updated the firmware in the BMS and the SOC went to 99%. What does all this mean? I have not done any additional testing so I don’t really know. The one thing I was able to do was look at the battery cell menu and I see the that there are some differences in voltages between cells. Does anyone know if this is normal? How much of a difference between cells (if any) is acceptable? In an AC200 Max that was also on site, the cells all looked identical when looking at the voltages so I expected the same from the B300s. Any ideas?
Thank you for your response. I will try to get a photo to display the values when I get an opportunity. I have since tried to recalibrate several other Bluetti units (AC180s) but I have not been able to see if the recalibration process worked in those cases. I have a couple of questions about the general process and also one pertaining to the need for recalibration.
1). Is there any cases where you have to go through the recalibration process two or more times for it to work?
2). During the recalibration process, I have been plugging the AC cable into another power station - Is it possible that the recalibration process does not work as well this way because it is charging from a power station with an inverter (as opposed to a wall outlet with grid power)?
3). In general, is it possible that the SOC on these power stations get more “out of calibration” if they are frequently being used with pass through charging? I often use power from these stations while simultaneously solar charging them and wondered if this would contribute to them being out of calibration.
Calibration does not require two cycles, one cycle is enough, that is, charging to 100% and discharging to 0% (must pass 0 and 100);
When calibrating, do not carry a load during the charging process, and do not connect to the input source during the discharging process (it is okay to charge from other inverters during the charging process, but it is recommended to choose an inverter with relatively stable output voltage and power)
Pass-through mode will not cause SOC inaccuracy (that is, pass-through mode is not the cause of SOC inaccuracy), and double charging will not cause SOC inaccuracy.
Thank you for all of the information and clarification. When you start at 100%, do you have to drain to 0% all in one session or can you start at 100% and then gradually use the power station down to 0% (and shutdown) over several sessions using smaller loads followed by a full charge via AC to 100%?
