Advice on battery only discharging to 5% and not topping up fully with 3017

Evening all. It may have been discussed before but I've searched and can't find anything.
Ever since I updated to firmware 3017 I never get the battery discharging to 4%. Only 5% and 10Ah left. Is this what everyone else finds?
It wouldn't be so bad, but after a couple of calibrations towards the end of last year, my 2year 3 month 9.5Kw battery is only charging to 181Ah. Middle of last year I was getting 191-193Ah before the upgrade to 3017 and later calibrations. Battery design is 186Ah and now full battery is back from last year 195Ah to 188Ah, but it only ever charges to 181Ah.
Being robbed at both ends! 😂
It is what it is, but in these dull old days, and having moved to IO Go, my charge time is 11.30pm-5.30am and I'm struggling to make the battery last through the day. Not an issue when I was on Cosy, or when we get 4Kw or more of solar, but having the battery shrinking isn't really helping. Be better too when the A2A heating is working less hard.
What do others get from their 9,5Kw batteries?

TimHutchings My 9.5kW shows a battery capacity of 182.13Ah vs design of 186Ah. It is 10 months old.
It discharges down to 5% most of the time as well as does my 5.2kW battery.

BMS 3015

Its hard to tell what charge and discharge I am actually getting out of the batteries as I am on Agile with Predbat so it gets charged overnight, then usually discharges a bit in the morning and then recharge ahead of the evening peak.

If you want to worry about not having enough battery capacity then get a heat pump and your battery is never big enough !

geoffreycoan Geoff. Whatever happened to the 4% supposed cut off? Your battery's top is worse than mine at only 10 months!

Mine is showing 179Ah full and 186Ah design. 22 months and now on 3018. Often goes to 3% or less and then does a sort of emergency slow charge back to about 5%. Givenergy said that was ok. As Geoff said the ashp empties it every day at the moment.

My 9.5 seems to be doing okay so far, after about 15 months - full shows 198Ah on rubikcube's app, and discharges to 4%. BMS 3015.

I do try treat it fairly gently - charge it at under 2kW overnight, and at the moment, discharge is limited to 1.5kW since it has no chance of lasting all day anyway. (We even use a low-power kettle to be kind to it.)
In the summer, I was giving it time to idle at low SoC to maybe rebalance. (I noticed just the other day that after sitting at 4% for a few hours, it bumped up to 8% briefly, which I interpret as rebalancing or recalculation of SoC.)

geoffreycoan Excuse my ignorance but where can I see the capacity vs design values?

DD I see similar SoC improvements whilst idle on my batteries on 3015. I likewise assume its recalculating its SoC.
I’ve put the SoC not dropping below 5% down to it probably needing a recalibration. I also see a spread of about 0.1V across the cells when discharging with one cell being notably below the others. A recalibration could well help both of these - but waiting for some decent cheap agile to make it worthwhile; and there’s always the risk that the recalibration will worsen the available Ah

GrahamShaul Excuse my ignorance but where can I see the capacity vs design values?

You need either @Rubikcube ’s Android app or to be running Home Assistant where you can get to the raw inverter data. Its not available in the GivEnergy portal

GrahamShaul Excuse my ignorance but where can I see the capacity vs design values?

If you're on android, https://givenergymonitor.wixsite.com/tutorials is a free app that can show many internal details of your system. On other systems, there's a bbc basic app that can do similar - https://community.givenergy.cloud/d/3660-can-we-acknowledge-a-bonfide-legend/10 though I don't remember whether it shows this detail.

DD On other systems, there's a bbc basic app that can do similar - https://community.givenergy.cloud/d/3660-can-we-acknowledge-a-bonfide-legend/10 though I don't remember whether it shows this detail.

it doesn’t, I had checked

"cap_calibrated": Def(DT.uint32, DT.centi, IR(84), IR(85)),
"cap_design": Def(DT.uint32, DT.centi, IR(86), IR(87)),
"cap_remaining": Def(DT.uint32, DT.centi, IR(88), IR(89)),

As an aside, I have been quite curious as to what cap_design2 shows for the 9.5 (or it's function) - on the old 8.2 i have that matches the original "cap_design" value, but as i'm 99% sure the 9.5 packs run at a much greater DOD than 80% (guessing in the 90-93% range) I wondered if this value is different.
If it's the same then I've no idea what it's purpose is (maybe it is used to limit the battery charge rates as they (AH value) are intrinsically linked to charge rates at the inverter end - sets lower value and get lower power perhaps?)

    "cap_calibrated": Def(DT.uint32, DT.centi, IR(84), IR(85)),
    "cap_design": Def(DT.uint32, DT.centi, IR(86), IR(87)),
    "cap_remaining": Def(DT.uint32, DT.centi, IR(88), IR(89)),

    "cap_design2": Def(DT.uint32, DT.centi, IR(101), IR(102)),

hoggy I seem to have 0x48a8 ie 186.00 for both cap_design and cap_design2

DD No idea then - is the battery above 20'C?

DD Like you on IOG, I fully charge in the overnight period slowly at about 1.7kw so it's done by around 5am. Keeps a little heat in the battery and is probably kinder too! Like you also I use a 2.2kw kettle, not so much to be kind, but the gen1 only outputs 2.6kw, so itsaves drawing from the grid.
You seem to be doing very well with your 9.5. Whether that's because you're being 'gentle' with it, or whether you have a 'well made' battery could be open to debate, but I'm glad it's behaving well for you.
The second self calibration I did late last year, I did do a really slow recharge at 600w, and managed to get a full recharge up 1 whole amp hour to 188ah from 187ah, and now a full charge reaches 181ah as opposed to 180ah. You're lucky to get down to 4% before cut off. I have a feeling that my 5% only started happening with 3017 and I was getting 4% with 3015.
It's only now I'm on IOG and I completely empty and fill the battery at 7p to make best use of the tarrif, that I'm really noticing the battery's extremities!

hoggy no, it's in garage. BMS is 20, other bits are between 13 and 15.

TimHutchings It's only now I'm on IOG and I completely empty and fill the battery at 7p to make best use of the tarrif,

Do you force a discharge at the end of the day, then start filling immediately at 2330 ? Now that I have a HP, battery is empty long before the end of the day, but during the summer, while I was exporting to not-quite-empty by 2330, I allowed it to idle for a full hour before starting the charge at 0030, to allow cell balancing. At the moment, I'm starting the charge at 0005 - not to allow the battery to idle, but simply because I find it convenient for accounting purposes to have all the charging and discharging happening within the same calendar day.

I think I did notice that it was finising on 6% some evenings recently. May it had gone down to 4% then gently bounced upwards to 6, but I don't think so.

DD On a bad solar day, and with the A2A heat pump working hard on these cold January days, I often run out by 10pm, so the battery has ample time to balance before the 11.30pm charge time. I do however find that with 3017 there are no battery jumps or rebalancing when idle. Maybe it's because I run it top to bottom each day. When on Cosy in October and November, I did find when I hadn't completely emptied it for just a few days, the SOC sometimes readjusted from say 14% to 10% as it dropped towards the bottom.
Now on IOG, if we get around 4kw of solar during daylight, I might have some left in the battery to export. I use the 'Inverter' app to see how much I’ll have left at 11.30pm and start exporting at a rate so it finishes around 11.15 -11.30pm, leaving the battery to settle a little before charging starts. If I'm out, the 'Inverter' app is scheduled to check from 9pm every half hour on the battery %, and if above certain levels, sets off export to coincide with emptying the battery by 11.15pm ish.
Seems to work pretty well!