We have an AC500 with two B300S batteries. The system is hooked to PV for charging and had been working great until we got a huge snowstorm that buried the solar panels. The two batteries were completely drained before we realized it. The AC500 won’t turn on - which isn’t surprising since the batteries are dead. The problem lies in that we have tried to charge the B300S’s (using the power supply charger) and the AC500 itself (using the AC plug to the grid) but nothing will charge. They’ve been plugged in for days with no charging at all. How can I get my batteries charged so the system will turn back on?
Hi @Kirij If your Bluetti B300S battery is dead, recharging it overnight at a low amperage or use the cigarette lighter cable to wake it up from the 12v followed by charging at a constant 7 amp rate from the AC.
It’s just because the batterie’s are completely drained you just need to start them slow.
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Hi @Kirij, We are deeply concerned about the issue you are facing. It seems the B300S has been over-discharged.
@Ktt’s suggestion is very accurate. Please disconnect from the AC500 and charge the B300S separately via DC. This will be very helpful. It is recommended to use car charging, and if you are using solar charging, please ensure that the voltage range of the solar array is maintained between 12-60V, and do not exceed 60V.
Please let us know if this is effective.
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Hi All.
Kirij’s dilemma & the knowledgeable replies begs me to ask if when draining the batteries every few months to recalibrate… Is it fine to recharge in standard mode (1200 w) or should I use eco?
Thankings.
Andy.
We have done as recommended here. We disconnected the B300S from the AC500 and attempted to charge it using 12V from the cigarette lighter DC output of our Bluetti EB70S. Nothing happened. The EB70S isn’t registering any output and the B300S isn’t charging at all. We’ve had them connected for a day and a half with no result.
Any other suggestions? Should I send in a support ticket?
Hi @AndyStuart, I appreciate your interest in Bluetti.
Normal batteries do not require recalibration every few months. It is only necessary when you notice abnormal charging and discharging speeds. Yes, standard charging can be used.
Here are some suggestions for storing the unit.
- Never store the battery empty, even for only a few days. LiFePO4 batteries might be unrecoverable if stored empty.
- Storage temperature: 0-40℃. Don’t store the battery in a humid environment. Keep it away from fire as well.
- The optimal state of charge for long-term storage is 40-60%.
- The battery will slowly self-discharge over time. The battery should be recharged every 3-6 months.
- Don’t store the battery on its side. Keep it up straight.
- Don’t stack things on top of the unit. Don’t block the fans.
Hi @Kirij, We are very sorry about this. Since DC charging did not help, repair is indeed the next option.
If you have any questions about how to reach the appropriate customer service team or concerns about the service process, please send us a private message with your order information so that we can arrange priority service for you.
I recently had such an issue as yours. If you are in a cold climate, as I was, it took days to warm the batteries with a little heater plugged in nearby. Then the batteries charged via solar. Hope it helps.