AIO SOC drop analysis based on Inverter Data

So, I finally bit the bullet and ran the numbers to try and get to the bottom of why the SOC drops keep on happening to me, which means I often get out of the AIO a lot less than the 13.5kWh advertised.

Asked another way

• is this a software issue i.e. the SOC / battery percentage algorithm (i.e. software) is flawed, or
• is this a hardware issue i.e. the AIO cells just aren't delivering as expected.

My source for this analysis was the Inverter data from the GE dashboard.

Notable events./ history for my device

Note:

• On commissioning, the battery calibrated, and I was on AIO firmware 607, BMS 6. I upgraded this week to AIO firmware 609, BMS 7 and the battery calibrated again, but not material improvement.
• I have had a few data gaps due to the internet being offline while I was away from the house (and no local data storage on the AIO).
• I have witnessed 10 separate SOC drops, in each case the required power out from the device (based on an expected range of 13.5kWh) would have needed to be considerably more than the 6kW supported. This alone suggests the SOC algorithm is wrong: either the AIO was much closer to empty than the battery percentage expected - or alternatively, due to a flawed SOC, the BMS is stopping the battery from discharging prematurely, because it thinks it's empty when in fact there is still charge remaining.

These SOC drops are almost perfectly correlated with when my AIO has got below a reported 25% SOC - see below candle chart which shows the reported SOC range by day, and the reported SOC at start / end of day. At other times the house load or solar production is such that the SOC% stays above 25%.

I then decided to try and calculate the SOC% for myself based on the PBat data field in the Inverter Data history. My maths was a simple approximation based on the area under the graph - effectively take multiplication of the PBat figure x the amount of time since the last data reading (in most cases ₅ mins), expressed as a percentage where 100% = 13.5kWh. Over the course of the 2 months, the calculated SOC deviated from the reported SOC a lot. So I anchored the calculated SOC to start at the same figure as the reported SOC at midnight each day.

This chart plots both the reported SOC (blue) vs the calculated (red). Using this method, the calculation of SOC regularly overshoots the reported SOC 100% max - in some cases by 20-25%. It is rare that the report SOC blue line is above the calculated SOC in red. This strikes me as a somewhat intuitive result for two reasons:
1) the anchor of the reported SOC at midnight day is wrong
2) depending on how PBat is calculated / measured - there are significant losses in charging the battery - i.e. what goes in when charging is cumulatively more that what it stored / useful when discharging.

To hone in on #2 above, I identified the times when my AIO reported "full" or "empty" when reaching 100% SOC and 4-5% SOC respectively. I then calculated the cumulative change in PBat x time between these peaks and troughs - i.e. how much energy it takes to go from empty to full, and how much it reports going from full to empty.

The difference was initially somewhat surprising to me - in most cases the AIO appears to be taking close to a full charge of c 13.5kWh, but what's coming out is often considerably less. This is particularly acute when there are a number of days between full and empty. Again my conclusion here is that the losses from partial charging and discharging are compounded.

And yet the last SOC drop for me was a quick return trip from full to empty during Friday's DFS event - I went from 100% SOC to 5% in just 80 mins - and this was just two days after a firmware update and calibration.

In conclusion

• I'm clearly getting a lot less than 13.5kWh out of my AIO when going from full to empty.
• The SOC% is not accurate.
• The losses from charging / discharging looks to be significant - potentially 20% of more

One thing you haven't factored in is that the battery is closer to having 16 kWh of storage so any drop of should be covered by that.

Im in the same boat Im getting at best 8kWh and losing in effect £1.50 a day due to it.

Im waiting for one more month, before I go back to installer to complain under CRA

DreadorUK Yes, I understand that’s the case but they marketed it as 13.5kWh so that what’s I’m expecting - anything above that would be a bonus.

I’ve started the conversation with my installer using this analysis as the basis.

26Left

Yeah I agree it should be 13.5 kWh usable

In my setup the way I simplify it is to look at charge time - its only charging for less than 2 hours (@ 5kWh) a night before it thinks its at 100%

26Left

Thank you so much for this post, you have summed up a lot of thoughts I had and put it in facts.

A few comments:

1. It is rumoured that GE may remove the mandatory 4% minimum for the AIO to give it its true 100% DOC. Do you think it would make much difference to your calculations?

2. There are 4 x 4 kWh batteries = 16 kWh (in theory). AIO says 13.5, so that means there is 2.5 kWh spare, does this still work with your calculations as well? (16 - 4% does not = 13.5)

3. Do you think this is happening because there are 4 x 4kWh batteries in the AIO compared to 1 x battery in say the 9.5 kWh version?

Daveb01 thanks - was keen to pull the figures and articulate the challenge as I see it - and get feedback from others as it’s just my interpretation, and I’m sure there’s a lot more for me to learn. What I can’t tell at the moment is whether it’s just a software issue, or the hardware can’t / won’t deliver the useful range under real life operating conditions.

In response to your questions:

1. Not sure it will change much, unless the SoC algorithm is changed as a result. I suppose it’s possible that it asymptotes to zero percent - ie you get a disproportionate amount of charge from the last few %s - but I think it’s unlikely. I think I’ve read elsewhere that if the cells are totally flat they might be damaged / irrecoverable.
2. I’ve based my calculations on 13.5kWh useful range as advertised. I’ve ignored that the capacity is closer to 16kWh according to other sources (like the GE “inverter” specification accessible via the dashboard). If I used 16kWh as the denominator for the calculated SoC it wouldn’t overshoot as much (red vs blue lines above).
3. I honestly don’t know. I think I’ve read elsewhere that the battery chemistry is different for the AIO vs the older design battery units, so that may be part of the problem too - apparently it makes it harder to accurately measure and calculate SoC.

If it is just a software issue, it is a pretty severe one. I haven't even had mine for 2 weeks, and it's already down to the point where going from 5% to 100% only pulls in 7.75 kWh. Since install, each day the SOC begins its instant plunge to empty at a higher and higher percent, which also matches with my grid to battery number decreasing each day. It now drops from 47% to 0 in a matter of 5 minutes.

The first time it charged, it took 2 hours to fully charge at 6 kw. Now, it's only charging for 1 hour 45 minutes at a rate of 4.3 kW before it reaches 100%.

What a great piece of work. I've had my system less than a week and have been experiencing increasing levels of SOC drop on consecutive days. I don't yet know how much I can trust the data in the portal, but some QAD calcs seem to indicate that despite reporting 100% SOC after a 'full' charge, the amount charge taken to get to that state from the previous 4% cut off was not enough to achieve 100% (even if losses were ignored). Other responses to your post seem to mirror this conclusion and it's not very comforting to know that either the batteries are incapable of delivering to their full potential or that the software (firmware) is preventing them from doing so.

Is it time to question whether the AIO is actually fit for purpose? I've had the system a very short amount of time and have only just had my eyes opened about these issues, I'd like to give the AIO a fair shake of the stick but I don't want to get trapped with a product that doesn't actually do what the vendor says it does. I'm pretty sure my installer would likely say 'give the system a chance' if I went back with issues at this early stage, but if you are going to discuss this issue with your installer could you please keep us up to date.

Shaaaag thanks - and will do. I similarly wanted to give the AIO and GE a chance. But it’s been 3 months now for me since it was commissioned - and I’m losing patience.

Shaaaag

I have had mine since August and have had all the same experiences as above and other posts.

I look at it like this, there is an issue when the AIO was first made and tested, it started at v1, they released it to early.

We are now up to software v9 & battery v7. How many chances do they need. Does the Teslar powerwall/ Myenergi Libbi have this issue?

GE should pay for a battery specialist or rocket scientist to come in and look at the issue and fix it.

I was keen to get the AIO after looking at the specifications. When Company that quoted and we eventually chose to do our install did mention that there had been " teething problems " with the AIO. He was due to visit the big renewable energy show in Birmingham where Givenergy had a stand. When he got back he said that there had been quite a few installers taking them to task due to various issues but Givenergy had assured them that they were on top of the problem.
After joining this forum and readding this thread I looked more closely at the performance of my AIO which was installed about three weeks ago. I have just joined Octopus Flux and last night set a timed charge to 100% at the off peak rate. Looking at the graph this morning I see that my battery went from 12% at 02:05 to 100% at 03:30 - (ish) and imported 8.3 kWh of electricity from the grid. There's obviously an issue here, I didn't notice previously due to the newness of the system and the fair bit of Solar input last week which keopt the battery topped up.
I'm not sure of the best course of action, I can't see the installer being able to correct the issue as it seems to be more general and the disparate installers of our systems would seem to rule out an installation error.
Looking at the excellent post by @26Left, unless I am misunderstanding the table he posted, it seems that his system did successfully charge to 100% on the 22nd November? Would this indicate that the battery capacity is there,and some software / firmware issue is the underlying fault?

Daveb01
When my installer was quoting he mentioned that he had a Powerwall and it had been rock solid and also mentioned a few " teething problems " with the AIO that were being worked on. He said there was a price drop on the Tesla powerwall as a new version using LiFePo chemistry was on the horizon.

The capacity is "there" in the hardware as some (most?) people do have no problems daily cycling 13.5kW+ (including theDragon who works for them)
Quite why it is such a lottery is a mystery - but then again you can say the same for the normal Givenergy batteries that do this too...it must be incredibly frustrating to users, installers and GE themselves.

("you need to cycle it / it's just very hard" - I've 2 other systems with LFP batteries from other vendors, one of which is over 8 years old and they don't do it despite running all sorts of SOC regimes over the years so it CAN be done....)

As Ash says:
I can't lie to you about your chances, but... you have my sympathies

Just had a look at last nights data. My battery went from 12% to 87% in 70 minutes at a charge rate of 5.35kWh before tapering down to 3.32kWh and finally 1.81KwH to finish at 100% after 85 minutes. My import data since midnight shows about 8.3kWh from the grid. ( I set a charge limit during the recent cold spell thinking to spread the charge over whole of the Flux Import window to help keep the unit warm )

Started researching LiFePo4 batteries to try and learn more about the challenges with SoC measurement and how to prolong their life - some interesting content here for those that are so inclined from one of the Chinese manufacturers:

https://www.evlithium.com/Blog/lifepo4-battery-soc-estimation.html

https://www.evlithium.com/Blog/understanding-lifepo4-battery-capacity-decline.html

https://www.evlithium.com/Blog/maximizing-lifespan-lifepo4-server-batteries.html

My AIO was fine for several months after the July installation. But it's just this past few weeks started to exhibit the SOC drop. Now at the point it'll change from "empty" to "full" with about 8.5kWh put into it, and roughly that back out again, plummeting from 40% ish SOC to 4% in a minute.
I feel like I've been pretty patient with the teething problems, I understand new products often have issues to iron out and the danger of being an early adopter, but this SOC drop issue has been known about and acknowledged by GE for months and we've still no official word on the cause and what the fix will be and guarantee that it's not a hardware issue and that we will get the advertised capacity from the battery reliably.
If GE can't or won't give us that then I'll be going back to installers with the AIO as unfit for purpose for a full refund. I'm sure that'll be fun, installers trying to get install costs back from GE, not sure how that'll play out.

Barns My intuition tells me that more people will see the SoC issue as they become more reliant on grid charging to 100% and need the full battery range during winter.

During the summer months my SSW-facing PV array was topping up the battery into late afternoon / evening, and the overnight house load was less, so the battery was rarely going below 50%. Therefore the SoC issues (and rapid drops) weren’t as obvious (or happening at all).

PV battery charging was also likely at a slower rate in the summer, rather than the max grid supported charge rate of 6kW, which might also have a bearing on better SoC accuracy and the resulting depth of discharge.

26Left Certainly I do seem to have started seeing this issue since the heat pump (and thus daily consumption) has gone on, so I'm charging from empty ish to full twice a day now from the grid. Does look like a correlation there. But then, that's exactly what I bought the battery for - to reduce running costs of the heat pump - so if the battery hardware isn't up to that job despite being sold as such then that's not good.

My system was commissioned on 17th of November and I've been getting used to the web interface and the various graphs and options and trying to find my way around. I wanted to give the system time to settle down and get a better understanding of how all the parts interact. I take it my first course of action would be to contact Givenergy and get them to take a look at my system remotely and see if they can analyse what is going on, then at least I will have registered my concerns. I'm assuming that the people with the Givenergy 9.5 kWh units don't have the same issues? I like the idea of the AIO and its seamless integration with the grid and wondered what, should the worst come to the worst, what others would replace it with. 2 x 9.5kWh ?

I've had very similar SOC issues. I read that lowering the charge rate from 6Kw to 4Kw might help. I did this a couple of days back, I'm now see a much smaller drop off on the SOC. I also got over 12KWh of charge last night.

Tenkaykev RE: the 9.5 batteries, boy have I got a thread for you (put the kettle on)
https://community.givenergy.cloud/d/713-firmware-3007-has-not-fixed-sudden-soc-drop-to-0-problem

hoggy put the kettle on

Yikes. But not during the saving session! :-D

Viper funny you say that, I've just a few minutes ago lowered charge rate from 6k to 4.5k (as 4.5 will in theory still reach 13.5 charged in a 3hr cheap window). We shall see what happens tomorrow. Of course even if this "fixes" it to some extent, the battery still wouldn't be performing up to the sold spec - it'd just be a temporary workaround.

Barns

Great minds think alike, I have just done the same.

However I could not set it to exactly 4500w, I have had to set it to 4640w (the closest)
I have tried in the app and in the portal.

Daveb01 Got mine to 4480W in the app. I suspect the resolution of the phone you're using will define what the increments on the battery bar gauge thing you slide are!

Barns
Got mine to this now as well.

So either 4480w or 4640w, yours was closer to 4500w so you win 😀

Barns totally agree.

Daveb01 So interestingly after a 3hr overnight charge at 4.5kW rate it's managed to get 12.6kWh into itself. This is after a few nights of only 8.5kWh ish going in at 6kW charge. So it does look like a lower charge rate is easier for the battery to handle. Will monitor over the next few days to see if it's consistent. Not ideal, it should be able to cope with 6kW charging as that's in spec, but a tolerable workaround until firmware improves the situation.

Barns on my hybrid inverter, I believe charge and discharge rates are actually represented as % of capacity as an integer. So the resolution is 1% of battery capacity. But AIO might be different.

Barns

Mine was same, so think I will stick with 4.5kw to see if it continues.

However the AIO is like my kids you ask them to do something and they do something else as Jellybaby has said a few times, you set it to a limit but it does its own thing?

Looks like it went up to 4819w

Daveb01 Yes mine won't stick at exactly what I set via the app, and then it also somehow got reset to 6kW overnight without me touching anything as far as I know. Possibly something to do with the GivTCP and Home Assistant integration but none of the scripts I'm using touch the charge rate I don't think. Another mystery!

Shaaaag My installer has shared a response from GE following my complaint to them:

It looks like the problem being described is the SOC bug that we are aware of and are currently working on a fix for

We have a temporary iron out to reduce the instances of which this is seen but this doesn't get rid of it entirely yet

If they're happy for me to move the firmware and calibrate to the temporary fix, I can get this started on their go ahead

I’ve said I’m happy to try anything to get it fixed - so I am expecting them to load a new firmware version and recalibrate.

@TheDragon (GivEnergy) made reference to BMS v8 on test in a different thread.

26Left

BMS 8 is now issued, but not released for public use, but Tech desk can load manually and monitor

Had my AIO system install a week ago and gradually trying to understand it. I've already noticed a couple of battery SOC issues as described in this thread.
This morning AIO battery stats show a fall from 26% to the limit 4% within the 5 minute slot at 00:06 to 00:11. then a charge to 90% in the charge slot required only 9.65kWh.
Questions:
1 the 26% threshold looks suspicious - could this be a result of one of the 4 batteries being faulty?
2 can I find battery pack level statistics anywhere?
3 where do I see the MBS version for my system?

John_R_H
1 - possible, though unlikely, since I had the same experience and thought and it was just a BMS issue
2 - no, I believe not
3 - do you have either your Gateway listed under My Inverter on the web portal (you may need to scroll to see it), or another login for the web portal for the Gateway? Once you are looking at the maximised Gateway info on he web portal it's on the Software tab. (If you have two logins you can ask support to combine them btw)

John_R_H

Welcome to the SOC drop club Ive been a member now for 2 months and it only gets worse - Im expecting mine to be under 7kWh usable soon, as it gets worse over time.

I don't think its battery as I had a calibration done a few weeks back, and had 13.5 usable again for two days before off it went on the slippery slope yet again.

DreadorUK Mine does seem to be mostly "fixed" / workaround by setting the max charge rate to 4500W, I've been getting 12-13kWh charging from empty reliably by doing that for the last week or so. It seems I need to set it every time charging starts though as something sets it back to 6000W when charging starts.

From what I have read on the issues with the SOC drops on the AIO it would appear to be an issue with the BMS (or BMS-es), the balancing features and the float/absorption voltages.

Have a watch of this video - whilst not exactly relevant it goes into great depth about how various functions of a bms can work (and in theory "should" work).

What I suspect is occurring is that the State Of Charge of the batteries in the AIO is being reset when only ONE CELL reaches the 100% SOC RESET voltage.

However if all the other cells have serious voltage deviations (eg. lower) then when one of those cells reach the 0% Trigger Voltage you will see your State Of Charge suddenly drop.

dragon2905
That is a very good explanation (that I have not read about) and more like what it seems to be doing. Those with a single 9.5kwh battery don’t seem to have as many issues as us with an AIO and 4 x batteries.

Thank you

Daveb01 Yes they do - there's a thread with thousands of examples on here 🙂

On the 9.5kWh G2 I can state absolutely that it isn't just one cell, its all of them. There's under 60mV variation between cells so the explanation above isn't correct for the 9.5kWh battery.

FWIW I think the AIO issues come more from the fact that its two inverters connected together but that's no more than a hunch.

Edit - currently f/w v3015 is charging 9.5kWh batteries to the calibration limit (and beyond) if you let it (multiple cells above 3.55V). It shouldn't be doing that but here we are again with f/w that doesn't do what its supposed to....

dragon2905 Which video? I can't see a link.

In other news...

26Left I’ve said I’m happy to try anything to get it fixed - so I am expecting them to load a new firmware version and recalibrate.

On the 7-Dec my AIO was downgraded from version 7 to version 6 of the BMS (but still on AIO fw 609) and recalibrated. A week on it appears to be working better for me - after Tuesday's DFS session it slowly discharged to 5% without a sudden drop. Will be interesting to see how long it stays that way.

I haven't done the input/output calcs to estimate the useful output, but yesterday's data from the Energy graph suggests

• Grid to Battery (from 5% SoC to 100% overnight): 13.53kWh total. The last 5 minutes resulted in a SoC jump up from 91% to 100%, at a tapered rate of just 650W - so suggests it reached full earlier than the SoC algorithm predicted.
• Battery to Home (from 100% SoC to 49%): 9.24kWh. The SoC should be much lower in this instance. I suspect if I'd used an extra 3kWh during the day, I would have seen a sudden SoC drop as the battery would be empty but the SoC extrapolating the same pattern would still have been in the 30-40% range.

I'm charging at 3.5-4kW power rating overnight.

I'm aware that BMS v8 is on test.

The last two nights charging have shown my battery go from 6% to 100% after drawing 8.6kWh from the grid, on Tuesday/Wednesday and from 36% to 100% on Wednesday/Thursdaywhile drawing 6.5kWh from the grid. A quick bit of mental arithmatic seems to suggest that the total capacity of my AIO is just under 10kWh. Frustrating, especially at this time of year when lack of solar means that I'm relying more on the battery. Let's hope there's a fix soon.

26Left OOPS
https://www.youtube.com/watch?v=F6OnHQ0TEbg&t=716s

Vestas where are you able to see the Cell Deviation on your battery?
I haven't seen that anywhere in my Dashboard or are you using HA?

dragon2905 GivTCP will show it on G1/G2 batteries.

I don't believe GE have chosen to make the cell voltages visible to anyone other than themselves on the AIO.

Vestas Just wondered where you got this information from in your response......

On the 9.5kWh G2 I can state absolutely that it isn't just one cell, its all of them. There's under 60mV variation between cells so the explanation above isn't correct for the 9.5kWh battery.

FWIW I think the AIO issues come more from the fact that its two inverters connected together but that's no more than a hunch.

Edit - currently f/w v3015 is charging 9.5kWh batteries to the calibration limit (and beyond) if you let it (multiple cells above 3.55V). It shouldn't be doing that but here we are again with f/w that doesn't do what its supposed to....

The AIO thing is something @hoggy mentioned.

3015 f/w notes state 2 cells at 3.55V causes the calibration routine SoC to reset to 100%. It did that during calibration and now the battery charges to that limit every time. The calibration 100% SoC is NOT the user 100% SoC, calibration SoC is supposed to be a few percent higher. Edit - off topic but I think its probably the lesser of two evils, 3013 dropped cells to pretty low/decidedly dodgy voltage levels, this one sometimes causes overvoltage warnings. Easier to manage charge locally via automation than discharge.

Think I dealt with the cell voltages above.

Vestas On the 9.5kWh G2 I can state absolutely that it isn't just one cell, its all of them. There's under 60mV variation between cells so the explanation above isn't correct for the 9.5kWh battery.

Does the GivEnergy BMS have a cell-balancing mechanism? (I'm interested in 9.5kWh battery specifically, but other batteries too.)

DD It does have an internal calibration routine which runs when the battery is idle and below a certain SoC. It supposedly disconnects each cell in turn to check it and will write new values in the float tables (I think) when its below 20% SoC.

That's my vague understanding of what is going on. Probably wrong 🙂

Vestas That's how it could measure each cell. Is there a mechanism to rebalance? eg I think some cars shunt individual cells which have reached max voltage, to allow the laggards to catch up. But possibly only at 100%. (My Leaf can sit for an hour or more continuing to "charge" at 100%, doing this balancing.)

DD Nothing which is visible to users other than the same sort of stuff as your Leaf.

Vestas But do I, for example, have to charge GE battery up to 100% from time to time, to allow the balancing to take place ? Or can it balance it at any charge level, during the 30-minute pauses ? [Might be able to see the effects of balancing when looking at the cell voltages, though I appreciate that AIO doesn't currently offer that.]

DD

Does the GivEnergy BMS have a cell-balancing mechanism? (I'm interested in 9.5kWh battery specifically, but other batteries too.)

All BMS should have balancing features. It's how those features are triggered that make the difference between a good BMS and a bad one.

Of Grid Garage has spent ages trying to find the right BMS that enables all the features (that he thinks are necessary) to a DIY Battery build. That JK BMS looks like it, very nearly, solves all the problems he was experiencing with other models and other brands.

There will no doubt be an "element of parts sharing across systems".

If your into the more technical side of things I recommend watching some of his vids. Whilst they are not applicable to GE equipment understanding how individual cells and behave and how the BMS features permit the standard operation of a battery is useful.

dragon2905 I know how BMS operates in general - I've a lot of reading wrt EVs. It's the GE specifics I'm really wondering about.

Im going to tread carefully lest i get caught up in NDA knots again but visually the 51.2V packs use a Lapis (now Rohm) ML5238 chip and an ST co-processor.
The Lapis chip does have balancing features although I'm not entirely convinced some firmwares enable them given the number of rainbow cell graphs that show some pretty bad cell imbalance. Perhaps they only run on a calibration or some other undetermined timespan. It'll be voltage levelling type (think like a canal lock) there is no bleed resistor for the other way.
(I took a look at the BMS, if you search "Lapis" on here you'll find it)
I belive there are a couple of versions (atleast 2) over the years although I think they are fundamentally the same design, the 9.5 packs just seem to have more suppressors on them than the older stuff.

For AIO it can't (or atleast shouldnt) use the same Lapis/Rohm chip as that tops out at 16S. I don't believe they even do a chip capable of 24S for each battery module in the AIO so no idea what they run. I believe the Co-processor is likely the same however.

The 2x inverters welded together in the AIO is just a hunch. Neither confirmed nor denied and I don't have one to play with so that's that. Why reinvent the wheel with an entire new design if your already building an EMS box for your other inverters...and so on...

hoggy Thanks hoggy, a brief read of the datasheet and I now understand why GE are screwed in terms of SoC management.

Thank gods that there's local control via GivTCP is all I can say 🙂

Edit - Doesn't look like any functionality has changed on that chip since 2020 - the name on the packaging is the only change in the revision listing since then so 9.5's should all be the same.

Vestas the Lapis chip actually goes back to 2012 (perhaps further) however it's just an IO type design, it has to be told (by the co-processor) what to do about the information it is seeing (cell voltages and so on)
This is where the GE firmware mods happen, taking info from the Lapis & then telling it what to do (Lapis do offer an all encompassing version that also has its own processor - not used by GE however). Hence why they are able to tweak it (within reason, the processor does have its limits)

The BMS differences are external to these chips, if you side by side the 9.5 with any of the "older" ones there are subtle changes (most obvious being a lot more suppressors as mentioned earlier) although equally they are still not that far removed as you occasionally see "Prime" branded batteries pop up in the groups and they still seem to load 3013+ FW fine...

hoggy Its a very old design hoggy - there were similar chips around for military usage in the mid-late 90s (Analog Devices IIRC), this one just has more i/o and a spi which wasn't really required for the usage cases back then.

Edit - also doesn't sound like there's a lot of build control going on during manufacture of the kit GE sells which I'm sure makes life "interesting"....