Hi,
This used to happen on the older firmwares, but last night my battery dropped from 70%SOC to under 10%SOC without any load or discharge.
Should I be worried? I have already emailed SUPPORT, but don't know when they will get back to me.
The portal also shows a notification for new battery firmware (from 3015 to 3017). I'm not sure I should update it now...
Any advice or experience?
I had exactly the same issue and found this happens on the seventh or eighth day from the previous occurrence. Support informed me that this happens if you keep the battery above 50% and by not fully discharging the battery once a week it loses it's tracking of the SoC and doesn't know the reference points of fully charged and discharged. Every time mine did this I was losing on average 5Kw every week to nowhere! Apparently 3017 which I've upgraded to is supposed to sort it out. I'll wait and see.
3015 and 3012 were also supposed to resolve this problem. They are much better at it than the other versions.
The main resolution though is to cycle the battery on a regular basis. I found a once a week full discharge to be sufficient to eliminate the SoC drops.
I haven't had an SoC drop since I moved to 3015 back in November and I stopped doing weekly discharges at that point. Since January, however, I've been more actively managing my battery (discharging in Flux peak export times) and as a result my battery doesn't stay above 50% for more than 24 hours.
After my experience with 3013 I'm reluctant to move to 3017 until I'm sure there aren't going to be any problems.
Just as an update and probably close this thread. Got an email exchange going with Support. Their only excuse for this happening was that it was on an old firmware and that I should update to 3017 asap.
I did the update, successfully so far. It has been running on it for a couple of days already, and no further issues. I was surprised that there was no calibration initiated by the update. Support confirmed that this is the standard procedure at the moment.
SJB I found a once a week full discharge to be sufficient to eliminate the SoC drops.
Perhaps related to this and the LiFePo chemistry used in the batteries, I took a look at the Tesla Powerwall 3.
From what I've read the Powerwall 3 does a complete charge / discharge / recalibrate every three months if i understand correctly. Perhaps this is their way of dealing with any potential SOC issues.
nigelr0 2x8.2kWh, AC coupled. FW 3015 - Support also told me the same. However my battery regularly exports to below 20% SOC 3 or 4 times a week and recharges to 100% every night. Yet I have had 3 random SOC drops of 20%-35% in the last week.
I am reluctant to update to 3017 because every FW update I have completed, in 2 years, something goes wrong! Last time necessitated a 4 week wait for a field visit to replace the inverter which just loved the update to FW205 :-(