Lithium batteries falling from 45% to 1% within seconds.

[Ulquiorra]

Trying my luck here before going the expensive route of contacting a solar installer.

I have 3 lithium batteries connected to a 12kw luxpower inverter. The system is around 2 years old. Recently when it hits 45% battery power, everything switches off. However all lights on my batteries are green as if nothing is wrong. Any help would be appreciated.

The graph will show the hectic dips. I tried tonight to restart my batteries and see if that fixes it but to no avail.

Edit: Batteries are CFE-5100s

 

[Mike Hoxbig]

When it goes to 1%, how long before it hits 0%? You may have a BMS issue. Shouldn't cost anything to contact your installer, it should still be within warranty...

 

[B-1]

Sounds like a dead cell.

Try shutting everything down then start it all up and set the inverter to charge the batteries to 100% for a day and see if it recovers.

The installer will hopefully have a cable and software to see the voltage of each cell and can advise you better of what's wrong.

 

[Ulquiorra]

When it goes to 1%, how long before it hits 0%? You may have a BMS issue. Shouldn't cost anything to contact your installer, it should still be within warranty...

It stays 1% till power comes back so 2hours.

 

[SauRoNZA]

Yup sounds like a calibration issue.

Charge it to 100% for a day and see how it goes after that.

 

[hilt_ctn]

Further to the above, if it is in fact a calibration issue, you're likely to see it hit 100% and then carry on " charging " for several hours afterward. At this point it's actually cell leveling, an important process for lithium batteries which needs to happen on a fairly regular basis.

 

[Sinbad]

It's also possible the battery is faulty. I had similar behaviour on a byd a few years ago

 

[leon.davibe]

yea at that voltage there should be lots of gas in tank still

it is likely a balancing problem
change the charge rate lower to be below the charge level that one battery can handle

and change settings to power load from eskom and let it charge full properly can also lift the float voltage to match the charge voltage while doing this to give it time to get all 3 100% full and balanced

it is a big inverter so it likely requires multiple batteries to be online to meet the capacity
so if batteries are out of sync and one or more shutdown low voltage the inverter may trip the remaining battery/s overload if load exceeds it max draw

the SOC is calculated by adding 3 batteries together so even if the remaining battereis tally up to 42% if they can't match the demand they will trip overload

after balancing a capacity test would be a good idea to see if you need to try and get gaurantee replacement