For a few weeks we’ve been having unusual charging and discharging resulting in ‘spikes’ in the app and desktop graphs. For example, one day at 12:30pm the 9.5kw battery was at 65%. Just 15 minutes later at 12:45pm it was at 99% which shows the ‘spike’ at almost vertical. This has occurred several times and additionally during the middle of the night the battery is discharging rather quickly when very little is being used in the house resulting in a near-flat battery by morning.
We downloaded the latest update to the inverter last week but this is still randomly happening.
Having contacted Givenergy almost 2 weeks without reply, we contacted them again two days ago, again without a reply as yet.
Does anyone know what the cause is please?
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the spikes are not charging and discharging, your battery cannot charge at that rate
what is happening is that your battery is self-correcting its idea of what the state of charge (battery level) is
my guess is that through the summer you have not used your battery much, its been fully charged or near fully charged most of the time. Keeping the battery full is a cause of the battery loosing track of the SoC.
The fix is to fully use your battery periodically, to let it discharge to completely empty and to refill it to totally full. This well enable the battery to recalibrate itself. You can do a battery recalibration as well but running a full cycle would be the first fix
Youtube video on the givenergy channel about this
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I too have had this twice now in a week on my AIO with BMS 12. I have used the calibration option to fully deplete and charge.
The first time it was discharging overnight as usual then went from 70% to the 20% cutoff and then pulled from the grid. Recharge happened at a normal pace.
Today, I was at 6.62kwh capacity and kicked off an export with a 3.68kwh limit. That stopped 20 mins later when I hit 20% (1.98kwh) which equates to a loss of 4.6kwh in 20 mins. Even the full hour shouldn’t have discharged that much.
As mentioned. I calibrated after the first anomaly and rebooted the inverter to make sure.
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My charts are like a hedgehog, and across the various views on the app / portal the system cannot decide a consistent soc to report. One version saying it is pegged around 50%, another saying it is working in the 85-100% range. Curious that the official recalibrate method doesn’t hit the spot. An overnight update to the firmware hasn’t fixed it either. I am going to try the deep cycle trick this evening, using the quick settings buttons, instructing a forced discharge in the 4-7pm window, followed by a forced charge in the 2-5am window.
I tend to run it from 100% to 16-17% and back up to 100% daily. (one cycle a day) all year round, and see very little (none) SoC% adjustments, it just works.
It’s designed to do it, so I use it. The four dropsm on the right are data drops, not corrections (detail at bottom)
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I’m going to let it run itself out rather than use the calibration.
If that fails I’ll see about a manual BMS update as nothing is in my portal but I see a newer one is available in the installer downloads
Here’s my 4+kwh drop in 20 mins.
thanks for your input everyone, I’ll see how it goes in a day or two after emptying and refilling the battery.
That pic looks fairly normal and good.
Mine? The drop of 4kw in 20 mins suggests a 12kwh discharge rate. It was only discharging at 3.6.
I can see what I guess is 45% down to 20% in about 30 mins at about 3.75kWh load without knowing the system if it were a 9.5 battery that would be about 2.25kWh.
Without more detailed info it’s hard to say
13.5 AIO
Was at about 6kwh storage down to 2.
I’ve now done a calibration and a natural run down and up. And it’s done it again.
Nice steady drop. Values in line with capacity and usage but the kettle was on and it went form 43% to 13% in 5 mins.
It lost 2.81kw of power in those 5 mins. That’s a 33.7kwh discharge rate. Is it even worth reaching out to giv support?
To re-emphasise, your battery did not lose 2.8kWh in 5 minutes, it was never there and your inverter has lost track of the battery SoC level.
The inverter cannot measure battery level, it has to derive it from battery voltage. When you do a calibration the battery is fully discharged and fully charged and the inverter records what the empty and full voltage levels are. From those data points it derives what the SoC percentage must be.
All good, but the nature of these batteries is that the voltage ‘curve’ is quite flat across most of its range, so the difference from say 10% to 30% is tiny, so any slight inaccuracy of measuring will result in an incorrect SoC level and thus a significant drop when the inverter realises the error and recorrects it.
The AIO’s have had a lot of problems with this, the advice has been to upgrade to the latest firmware which has progressively improved the SoC tracking, and to do a calibration to reset the data points. Its also worth doing a slow rate calibration, do the calibration but set the charge and discharge rates to low values so the battery slowly empties and fills up again - this can improve the accuracy of the SoC tracking.
Do keep pressing GivEnergy support but I think you’ll find they give the same advice. There’s quite a few people who have had similar problems with the AIO on the original givenergy forum, this is what they did