Battery power drains into thin air when lower than 50%

We have a 9.5kw battery. If it is on around 65% at midnight it will generally still be showing around 50% when the panel generation starts up in the morning. However if the battery level falls below 50% during the night the power falls off rapidly.
Last night in an attempt to ‘protect’ the level I charged it to 60% for 40 minutes before midnight and set it to not fall below 50% from 2am to 5am on Octopus Flux.
This morning from 6.11 to 7.22 (1hr 11 mins) it fell from 50% to 14% according to the System Data with very little demand from the house at this point.
This equates to around 3.5kw but the Meter Data shows Discharge of 0.3kw.
So 3.2kw approx has ‘disappeared’. We effectively now have to pay to recharge as we will not be able to export today.
This is a repeating issue that I have tried to get GE to look at since our installation on 18 Aug.
Has anybody had a similar experience, or a solution?
We think there is a battery or inverter fault.

This is a fairly common problem with the BMS. It can misreport the % charge in the battery and often occurs when the battery has not been fully discharged for a while.

I think it was pretty much fixed in firmware 3012 but is a problem in firmware 3013 and those earlier than 3012. You'll find lots of posts in this forum about it. GivEnergy are working on the problem.
The best work around is to fully discharge the battery on a regular basis.

I never experienced the problem when my battery was on 3012, but I foolishly upgraded to 3013 and get it every week or so.

You could ask support to put your battery on 3012 to see if it improves matters.

If you are getting the problem every day then something else is wrong.

Thank you bbttyy1 will try the fully discharge idea. Presumably that means to 0 and not keeping a 4% reserve for potential power cut?
We noticed that this issue did not occur for first few nights of October but then kicked in. It seems to happen when battery goes below 40%, then it just drains quickly with little demand.
I’m pretty sure we have already been set back to 3012.
It took me a while to reply as I didn’t even know how to locate my own post!

@nikkian Please check which software you are on, 3013 has the potential to flatten your battery. Transfer to 3012 ASAP.