Sure - I’m going to collect the data for you and I’ll post it up with what you suggested

I've switched over to voltage mode tonight and will be keeping a close eye on the charts, will then post my findings. 

PS. When referring to battery capacity, please remember that stored energy is measured in kWh, not kW (apologies, it's my engineering OCD... 🫢) 

Hi @HendrikBigChief here is hopefully what you need/asked for

Whole 24hr for the day in question

Battery voltage is 53.99-54.00 from 00h00 to 09:28:29 when I start the run down - rundown below

 

At 7% Eksom feed is restored - next images are charging @40amps

Finally from 22h00 to 23h59 is a loadshedding slot with my usual base load of 480-630watt TV, fridge, routers, fiber and a few devices in standby etc. that base load comes into play most days from about 20h30 and will reduce to about 340-480watt from 1am to 6.30am

The latest firmware update (13/06/2023) from CFE eliminated the SOC cycling, prior to that the update the did changed SOC to cycle between 100-95% & before that it was 100-90% when the system was originally commissioned.

Here is the 13/06/2023 data (last firmware update) you can see the batteries drop out at 12h48 this is when the firmware was updated the batteries where powered on/off twice. At 16h06 you can see the same catastrophic issue appear again after reaching 100% "SOC" at 13:55:53 until 16h06 when load shedding starts and at 18h01 an active load kicks in, @18:07 its hits 46% and @18h13 10% just as Eskom power is restored and at 21h13 100% SOC is achieved @ 53.49v

The below is from Solarman, a steady SOC @ 100% for 6+hrs - it would appear that in data going back to commissioning date, float voltage has always been 53.88-5399 and now 54v after the latest update - charge voltages have always been maintained up to this last update at 56.1v I believe for LFP charging in parallel the parameter is normally 56-56.8v

40 minutes ago, JAK said:

I've switched over to voltage mode tonight and will be keeping a close eye on the charts, will then post my findings. 

PS. When referring to battery capacity, please remember that stored energy is measured in kWh, not kW (apologies, it's my engineering OCD... 🫢) 

lazy typo's on my part sorry yes I know its kWh...engineering OCD is welcome  

Update: now you triggered my OCD - updated posts to kWh for this thread as much as possible - thanks for contributing to my insomnia  

Edited June 19, 20232 yr by TheMafiaMan - NotMuffinMan

9 hours ago, TheMafiaMan - NotMuffinMan said:

Hi @HendrikBigChief here is hopefully what you need/asked for

Whole 24hr for the day in question

Battery voltage is 53.99-54.00 from 00h00 to 09:28:29 when I start the run down - rundown below

 

At 7% Eksom feed is restored - next images are charging @40amps

Finally from 22h00 to 23h59 is a loadshedding slot with my usual base load of 480-630watt TV, fridge, routers, fiber and a few devices in standby etc. that base load comes into play most days from about 20h30 and will reduce to about 340-480watt from 1am to 6.30am

The latest firmware update (13/06/2023) from CFE eliminated the SOC cycling, prior to that the update the did changed SOC to cycle between 100-95% & before that it was 100-90% when the system was originally commissioned.

Here is the 13/06/2023 data (last firmware update) you can see the batteries drop out at 12h48 this is when the firmware was updated the batteries where powered on/off twice. At 16h06 you can see the same catastrophic issue appear again after reaching 100% "SOC" at 13:55:53 until 16h06 when load shedding starts and at 18h01 an active load kicks in, @18:07 its hits 46% and @18h13 10% just as Eskom power is restored and at 21h13 100% SOC is achieved @ 53.49v

The below is from Solarman, a steady SOC @ 100% for 6+hrs - it would appear that in data going back to commissioning date, float voltage has always been 53.88-5399 and now 54v after the latest update - charge voltages have always been maintained up to this last update at 56.1v I believe for LFP charging in parallel the parameter is normally 56-56.8v

Thanks for all the charts, there seems to be at least one issue, possibly two.

So I suspect your battery is not fully charging which is possibly due to your BMS setting your charge voltage too low. Like here:



Here is a chart of a correct charging to full on my system. Notice how the charge current slowly goes to zero and not steeply like on yours. 

 

The second issue is that when you pulled 113amps, the battery could not cope with it for very long. Many things can be causing that. Your voltage does not drop too badly, but the battery BMS made the SOC drop very fast. It could be an issue with the calculation of the SOC on the BMS. This might be resolved if the battery gets fully charged using the voltage method instead of the BMS.

At this point my recommendation would be to run the batteries in Voltage mode with the settings I provided earlier. I know you don't want to void your warranty, but it would be interesting to see if it improves the charging profile. It would be interesting so see the charts for that as well. If you would be willing to run it over one charging cycle I would be able to tell if it is charging correctly from the charts.

HI @HendrikBigChief tried this morning as a last ditch effort to put the system into V mode as you suggested - it would seem since the latest firmware update I cannot do this any longer as the batteries once booted up, inverter restarted and connected back to the batteries - immediately trip into a fault mode when the inverter initiates the connection - so SOL.

Thanks - I know you where try to resolve my problems and at least see what the batteries where doing but as noted I'm returning them - the question now remains what to get and if my supplier can supply something they don't normally stock  - will have to see

SolarMDs 14.3kWh battery seems to at least according to their spec sheet have the most honest representation of what/how the battery will perform - and if I can make some modifications to my loads and not exceed 4kwh loads at any one time then I can follow their recommended 13kWh useable storage @0.3C or +-3.9Kw load

I'll post back here what happens next...thanks.

On 2023/06/18 at 5:22 PM, TheMafiaMan - NotMuffinMan said:

So this is my last ditch effort at trying to work with CFE before I throw the towel in completely on these batteries...

My printed manual and some of the online versions I found show the parallel connection of 2 and 4 of the batteries as per Fig1

Fig1

This afternoon while digging and digging and digging some more to get some last ditch info I stumbled across another CFEnergy site and downloaded a manual dated 20230321 and found this diagram for parallel connection which looks like this Fig2 - the main difference being that the positive of the first battery and the negative of the last battery are what go to the invert - as apposed to the positive and negative on one battery going to the inverter and the two being bridged in the same way.

Fig2

Anyone who has these CFE-5100s batteries 2 or more @JAK, can you please confirm what is the correct connection method or if it makes no difference? Mine are currently connected as per fig 1 but this might now be incorrect...though I have no errors or faults so maybe its nothing - I've also confirmed after watching a very long training video conducted here is SA with CFE that:

A) The white units which have serial numbers starting with 1416x are from 2022 - so that's good its not an old battery from 2021 - and mine are 14168xxxx which denotes batch 8 from around Aug/Sep and its is definitely a v3 of the 5100s and has the newest version of their BMS - apparently v1 and v2 where different.

B ) in the video an installer or reseller mentions or part answers a question about the cables as per what I'm asking above and its even more unclear whether FIG2 is for series connections as he sort of confirms then back tracks on with some mumble about that not being correct...or that you wouldn't get 200ah and only 100ah blah blah- frankly I really don't care - he confirms how clueless most installers are and that they use us as guineapigs.

FFS!!! which of any of this is actually correct or valid and can someone take a picture of there CFE units so I can compare - please.

Thank you in advance.

Hi MafiaMan

 

New here.  Figuratively and literally. 

 

I have two CFE 5100s connected to a 5kw Luxpower SNA. 

 

The Bats are connected as in your figure 2.  (positive of one and negative of the other goes to inverter).  I also noticed that the manual actually suggests otherwise, but my installer has these CFE's in his own home and I gathered he has more experience with them. 

 

Mine has been going strong without much incident from end March this year.   I have only experienced the cycling between 90 and 100 soc, to complain about.  It has never done the massive drop.  Lowest soc has been 20%.   Even with the cycling, PV charges the batteries to 100% and it then starts to discharge to 99% using only battery.  It will then proceed to use PV and a small bit of battery, but will not start charging the bats again until they have hit 90% soc. 

 

Nervous that I mind end up with the drop as you and others have experienced, but have been lucky thus far.

 

I have the battery app running and this at least gives me a glimpse into the individual cell levels and to check for imbalance. 

 

One thing that I note you mentioned is that C rating.  Now I noted some spec sheets listing these batteries as 0.6C (therefore max 3000w draw).  That is part of the reason I got two as I thought this would "stack" so I could theoretically draw 5kw (max of my inverter).  Through careful use though we have not gone over 4kw.  But have not had any cut out due to "overdrawing" on the bats.  Wonder if I must run a test to see if I can actually get to 5kw draw.  I thought I could until I read your posts...   (Edit:  Both manuals of my bats actually claim 100ah discharge) 

Edited June 20, 20232 yr by New

27 minutes ago, New said:

One thing that I note you mentioned is that C rating.  Now I noted some spec sheets listing these batteries as 0.6C (therefore max 3000w draw).  That is part of the reason I got two as I thought this would "stack" so I could theoretically draw 5kw (max of my inverter).  Through careful use though we have not gone over 4kw.  But have not had any cut out due to "overdrawing" on the bats.  Wonder if I must run a test to see if I can actually get to 5kw draw.  I thought I could until I read your posts...   (Edit:  Both manuals of my bats actually claim 100ah discharge) 

Welcome @New

As you can see I've not had a great experience - your SOC cycling between 90-100 suggests 2 firmware version earlier than mine now after 2 updates - mine did that originally - purchased in Nov 2022 you can see in the post how to determine which batch and version battery you have but if you bought it in the last 3-6 months its the v3 most likely - mine is too.

My advice - don't update the firmware if you're not having any issues - I hope unlike me time doesn't paint a different picture - if you can get below a 20% SOC then you're already better off than I am, whenever my batteries hit 40% SOC they'd drop to 7/5/1% in 2-3 minutes.

Maybe as a caution, C rating doesn't stack as people think it does - I've seen multiple installers, resellers etc. say that 2 x 0.5C batteries gives you 1C. That is not correct. Assuming you have 1, 4 or 8 of the same battery rated at 0.5C your storage capacity is doubled, quadrupled etc. but in essence if you want to realise that stored energy as efficiently as possible then you would need to use it at 0.5C or even possibly 0.25C

Basic rule" C rate doesn't stack in Series

In parallel connection the C rating is wrongly attributed to stacking the load because you're "1/2 ing" the current between for example 2 batteries - think of it this way the faster you discharge them "Higher C rating" the less electricity you get out over time.

At it's simplest Its the electric car example - lets use a TESLA - freekin quick but if you thrash it in 01-100 launches and max performance pulls what happens - batteries overheat and your range i.e. usable storage disappears and becomes much less. fast = more power, more power = higher C rates 2C, 4C 8C etc.

I used to in a previous life fly large commercial load-bearing drones - we'd have large LIPO packs that you could pull/discharge at 25-40C for about 2-3min in specialty situations and then they'd unceremoniously die or you could fly reasonably at 8C and get 10-12min

If you where unlucky your drone would plummet out the sky or if you where a good pilot you'd monitor voltage and current like a naughty kid in a park and landed it just before it was about to expire - I was one of those pilots that was careful and I have only ever lost one drone - I "infamously" drowned a very large, very expensive drone 10yrs ago that had a faulty BMS and I ignored the V and C rates for 5-10 seconds - it landed itself in a large dam - police divers had to come fish it out. Needless to say my "employers" where not happy with me - however telemetry data proved I wasn't reckless and that the BMS went "offline" about 15seconds before the drone became "unstable" - the lesson applies though.

200AH batteries discharged at 2C will not nett you 200AH worth of energy.

CFEs own data is misleading - an older manual states 5000w/3000w nominal i.e. 0.6C, the sticker on the side says 100ah or 1C and newer docs mention neither other than 1C charge and discharge - they cannot seem to decide which one - I would have to advise based on my experience that you treat them as 0.5C for charging and discharging.

My beef with them is CFE sell there batteries as 1C charge and discharge product - It cannot in my case reliably do 1C between the 2x 5.12kWh batteries and in Lithium mode the batteries die in 17min or less - now whether the SOC is wrongly calculated, comms are faulty or my batteries are not charging fully or discharging, I don't know, but we cannot spend the type of money we do on these to tinker - If I wanted to do that I'd build my own battery packs.

My advice after 7+months - there is no need unless a once-in-a-blue-moon emergency to charge your batteries at 1C - 100AH, i'd recommend not acceding 0.5C or 50A and I found 40A is a nice middle ground leaving your inverter some headroom to run other loads when charging - again ideal on a 8kw invert but I'd drop that to 20-25A on a 5kw inverter.

1 hour ago, New said:

I have the battery app running and this at least gives me a glimpse into the individual cell levels and to check for imbalance. 

PS the BESS app shows all 16 of my cells in each pack to be at 3.32V most of the time

As of right now the master battery is 16 cells @3.32v my slave battery has 13 cells @ 3.32v and 3 @ 3.33v - even when I've had the weird drops and such the cells are all according to the app fine and within normal range - and I've never had  the actual pack go into a full on fault mode other than once for a low voltage level 3 fault when they where completely drained and we had no power for 12+hrs

Anyway I hope you fair better

5 hours ago, New said:

Hi MafiaMan

 

New here.  Figuratively and literally. 

 

I have two CFE 5100s connected to a 5kw Luxpower SNA. 

 

The Bats are connected as in your figure 2.  (positive of one and negative of the other goes to inverter).  I also noticed that the manual actually suggests otherwise, but my installer has these CFE's in his own home and I gathered he has more experience with them. 

 

Mine has been going strong without much incident from end March this year.   I have only experienced the cycling between 90 and 100 soc, to complain about.  It has never done the massive drop.  Lowest soc has been 20%.   Even with the cycling, PV charges the batteries to 100% and it then starts to discharge to 99% using only battery.  It will then proceed to use PV and a small bit of battery, but will not start charging the bats again until they have hit 90% soc. 

 

Nervous that I mind end up with the drop as you and others have experienced, but have been lucky thus far.

 

I have the battery app running and this at least gives me a glimpse into the individual cell levels and to check for imbalance. 

 

One thing that I note you mentioned is that C rating.  Now I noted some spec sheets listing these batteries as 0.6C (therefore max 3000w draw).  That is part of the reason I got two as I thought this would "stack" so I could theoretically draw 5kw (max of my inverter).  Through careful use though we have not gone over 4kw.  But have not had any cut out due to "overdrawing" on the bats.  Wonder if I must run a test to see if I can actually get to 5kw draw.  I thought I could until I read your posts...   (Edit:  Both manuals of my bats actually claim 100ah discharge) 

There is no need to worry about the C rating in your case, your 0.6C battery bank can give you 6000w which is more than what you inverter can invert as long as you have the correct gauge wire and fuses installed. 

While a lower current is more suited to release the remaining energy inside the battery, LFP batteries do not suffer noticeble reduction in capacity when being discharged at 1C. Put differently, with decent LFP battery you will get close to rated capacity when discharging at 1C, you will not notice the difference.

Charging at high C ratings should be generally be avoided. When charging occurs at very high currents, the heat generated within the battery cannot be removed fast enough and the temperature quickly rises.

Hi dear friends

This is Leon CFE SA Local technical support engineer here

From your description, it seems one of the batteries in the bank is not chatching up with the others

0609413796 is my local No, WhatsApp the same, I will be around JHB most of the days

And now we have SA local service network, most of the big cities like Jozi Petoria Cape town PE Durban Witbank and more is covered by the servicing network

You are more than welcome to give me a call and I will help you with the issue ASAP (72Hours sorted)
 

Thx guys for sharing knowledge here

Best Regards

On 2023/06/18 at 7:14 PM, HendrikBigChief said:

@TheMafiaMan - NotMuffinMan
Also, the way we use the batteries in SA is not really what they were intended for, we not only use them as solar batteries, but we also use them multiple times a day as backup for load shedding. 

I am an european looking into building a PV system with storage that ended up on this forum because I was looking for info on these exact batteries.

And I was wondering what did you mean by that.

How could this not be what the batteries are for? May I be missing something? I am looking to store power for when the sun don't shine AND to serve as backup when grid goes down.

7 hours ago, PoweRanger said:

I am an european looking into building a PV system with storage that ended up on this forum because I was looking for info on these exact batteries.

And I was wondering what did you mean by that.

How could this not be what the batteries are for? May I be missing something? I am looking to store power for when the sun don't shine AND to serve as backup when grid goes down.

He probably means that we're cycling the batteries far more often compared to other parts of the world

On 2023/06/15 at 6:55 PM, TheMafiaMan - NotMuffinMan said:

Hi all - yes click-bait like topic for good reason.

Before I decided to write this particular post I also scoured this forum and noted that various users are having quite frankly unacceptable levels of SOC issues with all kinds of batteries even Pylontech and other "reputable" brands - so I'm starting to think that the majority (i.e. not all but 50-60%+) of the batteries and new makes and models that seem to land on our shores every other day, are simply not suitable for our unfortunate and insidiously unique power problems here in SA - I'm talking about frequent loadshedding, multiple times per day for 2-6 hours at a time, depending on where you are fortunate or unfortunate to be in our country.

Those that would like to follow previous long CFE discussions can view them  here  and I have a very long (sorry) but complete view of my installation, how I use it and the dreaded SOC drop from 40%-10% in 5 minutes or less or worse still 40% to 0% almost instantly here

For those that don't to go read them, a very summarised version is bullet pointed below which doesn't give you 100% context - so if you're going to ask questions or tell me I'm 'stupid' without referencing important info in the original post(s) - be warned - I'm called the TheMafiaMan for a reason...🤣

• 8kw DEYE inverter
• 2x CFE 5100s batteries setup as 30% restart 20% battery warning and 10-15% Shutdown. Final Battery setup will be 20kWh of storage via 2 more 5.12kWh batteries to be added in 2023 still.
• The system is protected by 200amp keto fuses and each board has surge protection as well - the house sits behind the inverter because A) I want clean pure sinewave power to all my plugs, lights and screens and B) fridges and appliances with inverter type motors are all better protected that way too. Your electronics will thank you.
• I charge the batteries @40amps so roughly 2kWh have experimented with 20amps and even 75amps - for my use case for now 40amps is my sweet spot giving my inverter head room to still run other higher draw loads when the batteries are charging.
• No solar currently, only used as a storage system to facilitate work from home and a "normal" quality of life (8.1kWh solar array is being commissioned)
• 6kva diesel Genset (dedicated generator room for Genset and fuel - already wired in with manual change over) just finishing off sound isolation, ventilation and then will automate change over with the dry contact and Gen feed-in on the DEYE Inverter
• Finally Eskom connection will capped off once solar is in and run in my own "Islanding" setup where I am my own "Utility provider".

Let me start by pointing out that my supplier for all my equipment mentioned is Solar Advice - solar.co.za and that they have been only helpful, support providing and quick to execute where CFE keep dropping the ball - silver lining they will be sorting out my problem without fanfare - the way a reputable business should and I keep recommending them over and over.

From my side I agreed to go through not one but 2 firmware updates with the "overseas - team" at CFE, resulting in about 75% of my frustrating 2+ weeks of irritability.

Let's get on with it - two plus weeks of frustration, hair pulling and plenty, and I do mean plenty of potty mouth later - I now have the latest CFE-5100s firmware on both of my batters and the great news is...

I am at least 50% worse off than before, cannot make it through 2hrs of loadshedding with 10.24kWh of storage and less than 2kWh load, and those that are good at math that means? Yup 79-80% and then 3% 3-5min later, and then off. Unacceptable by any standards - I mean are there a few AAA batteries inside my two 5.12kWh LiFePo4 units.....???

But this doesn't really paint the whole picture so let’s start in Nov 2022

• November 2022 system is commissioned and installed.
• Batteries are charged from +-56% to full over about 3hrs at 30amps or roughly 1.67kWh - for the Mathematically/Electrically inclined, 1602watt to be precise - DC wattage and AC wattage are not 1:1 parity 30amps at 53.4v is 1602watt - I was not charging my batteries at 6.6kw - if you think that, then this thread is not for you!
• load$hitting had not hit its full stage 6 stride at that time, so think mixes of stage 2/3, 4 and 6.
• Batteries were being used and run down to about 80-85% in stage 2 over 2 hours with mixed loads ranging from 1-2.5KWh and 55-60% in stage 4 or 6. We had no interruptions and not a single error or problems.
• We had a 12hrs long load$hitting event twice in the Dec/January and batteries hit 41% with a very OCD (me)controlled 350-450w/h load on these specific occasions – again no problems.
• Then we got into full stage 6 load$hitting 3 times a day - yep, I live in an area where we got 9-12hrs per day, day after day.
• Finally but irrelevant to the SOC issue like many other CFE and Raytech battery owners I had the 100%-90% cycle which I didn’t particularly have a problem with – go read the long post I made, to understand why – batteries should not sit at 100% for hours and days on end – I hope you have a fire extinguisher near – more info about that in my long ramble as well – go read it!

This is when the problem reared itself for the first time between 40-38% left in the tanks and the inverter would either throw anything from a F56DC_VoltLow_Fault usually followed by but no exclusively F58BMS_Communuication_fault to even one or two F59AC_V_GridCurr_High Fault – for this discussion the most frequent by an overwhelming margin is the F56DC_VoltLow_Fault just as or about when the system hits 11/5% or 3% whichever the Chinese battery lotto gods deemed fit that day and then off.

The First update which required the inter-battery comm cable to be disconnected - took less than 3 min OTA (over the air) – each battery has a WiFi Module and independent battery monitoring software that can only seem to report voltage correctly as confirmed with a Voltmeter - but is useless at doing anything else.

I was instructed to cycle the batteries a few times between 10/15% and 100% and Monitor it.

The looping 100-90% discharge had changed to a 100-95% loop but again refer to my first long post (yes this current one will probably become known as the longest waffle on this forum – hopefully I’m a little entertaining at the very least) I still didn’t take issue with that.

1 week later the batteries now don’t cut out at 40% but now “gracefully” (intended sarcasm) go from 80-60% in 3min flat, then on to 50% at a leisurely pace and then when they hit 43% descend rapidly form there to 30/20/10/5/3% and then dead in 5-10min.

CFE stop responding in our happy little WhatsApp group containing expletives of me telling them everything from "they don’t know anything about BMS implementation, firmware and code writing" to how generally useless they are in responding to real issues – this goes on for the rest of the week.

They then announce how sorry they are ("Sorry Dear"??? I'm not anyone's darling/dear), that there WhatsApp wasn’t allowing them to log back in but that they had triumphantly a “new” firmware that would sort out all my trouble 😊

Disconnect comm between the two batteries again, never hear form them for another day but during the early evening get plunged into darkness because the batteries are flat and now to add to my annoyance charge from 0-100% in 45min going form 40-80% in 5min because can you guess why? They’re completely unbalanced – remember the inter-battery comm cable is disconnected waiting for the firmware update that never happened, and I now spend the next 2 days manually discharging each battery – via voltage control not BMS (by now it should be apparent to you that the BMS is $hit) and then charging each one individually, paralleling them again and reconnecting comms etc.

Firmware the 2^nd finally happened on Tuesday this week – remember the one that will solve all my trouble😊 – batteries turn off after a successful OTA - Firmware update complete.

100-95% cycle now replaced by 100% and no cycling – hmm not too happy about that but I have other things to do, like work… and then Load$hitting that night 6pm - and 18min later plunged into darkness – 100% to flat - yes my troubles are truly over!

By now some of you probably have an idea as to what is the root cause of at least one of the problems – their BMS is beyond $hit – how do I know? Read on…

With torch in mouth while hurling profanity (I am quite talented you can tell) I disconnect everything to a safe point, reconnect only the master battery i.e., 1 of them and start everything up – switch to voltage monitoring mode to bypass the BM$hit (see what I did there) and apply a 4.2kWh load which runs for a whole 50min before the battery enters a fault mode and the solenoid disconnect trips – Thank god that actually works. Inverter shows voltage dropped below 47.9 (my own setting) and therefore the battery is at 5% or less.

Wash, Rinse, repeat – do the same with battery 2, the slave – and run for about 70min with a mix of 2/3.5 and 1.1-kWh loads during that time and then click - solenoid disconnect trips at 47.8v.

This all after the BM$hit declared that they where both flat to my poor DEYE inverter almost 2hours prior. By now I'm sure the inverter has developed or is developing schizophrenia.

Luckily by this time the power is back on and both batteries are at 1-2% each so I reconnect, re-parallel the batteries and connect the inter-battery comms and let the unit charge up in BMS mode (shocked I'm using the BMS again? There is a method to my madness) @40amp so 2.01kWh and monitor.

3hrs later we’re at 61% - great that is more or less correct, but then it all goes to $hit once again as 61-83% happens in about 10min and then 83-100% took 45min further – confirming my “rubbish BMShit” hypothesis in both directions conclusively. I did this 2 more times in both directions to confirm. Confirmed – in case you’re wondering - exactly repeatable.

I worked out on some spreadsheet – because I have time to kill like that – TheMafiaMan remember. At best, I can get about 6.5 maybe 7kWh of usable power out of my 10.24kWh storage but not without a massive, probably warranty voiding and time consuming workaround as you've seen above. Sorry, not good enough – I allow for 10% DoD as per the manufactures spec or maybe that should be claims. I paid like many people, a lot of money for storage, one of if not the most expensive single components in your system and I will not accept 60-70% and of that completely unreliable capacity – neither should anyone.

Anyone who has read this far – congratulations – but you must also by now agree, enough and no more. Which is exactly what I communicated to SolarAdvice – who have been privy to my WhatsApp “consult” with CFE and agree that I’ve exhausted all options.

I have options that I will be exercising and that is getting rid of CFE off my property once and for all – but this is basically a warning to all and sundry.

STAY AWAY from the CFE product – A properly working, reliable and trustworthy BMS in a LiPo, LiFePo4 and the like is non-negotiable.

You shouldn’t have to wonder if you can make it through 2hrs of loadshedding because the data you get from one of the most expensive items in your alternative power solution is “wonky” at best.

Unless you like dancing with fire – literally - and have a few chemical fire extinguishers on hand – you should have at least one with any large Lithium-xxxx-insert-your-particular-battery-chemistry-here anyway, but right now – for me, these represent a substantial electrical and fire risk to my property and the vehicles in my garage. I’m 100% not prepared to roll the dice on either side. Besides the fact that if you’ve followed my rant this far (thank you) this is not a workable use case and why I’ve had to postpone the Solar Array until I have reliably working storage solution.

As my intro eluded, this seems to be a far wider reaching issue cropping up on other battery systems too – so like others I’m left wondering what my options for a reliable battery brand are. One that can provide a battery system suitable for the SA market with our unfortunately unique power situation that actually works…

My Short list so far is 10-15kWh, 1C discharge rate and 10yr warranty

• SolarMD’s 14.3kWh battery.
• Freedom Won 15/12 battery -  but not so sure I'm onboard with Local-is-lekker - Solar MD are supposedly also local but I know of a couple of installations    with both brands that are more than 12-18 months old and have had zero issues with the batteries, so I'll need to investigate some more -  there is at  least one horror story which seems like a 5 year old model with 470+ cycles that is basically dead and FW cannot offer replacement cells because they're EOL(end of life) according to the comment placed this guy purchased 5 x 30/24 units which he must have sold organs for   
• LG Chemistry – I don’t believe I will be able to source or afford it – at the moment rated worldwide as one of if not the best, but a 16kWh unit is almost the cost of a Tesla Powerwall think €9,377.00 sourced international with shipping and then add what ever bend-over-tax when it gets to SA and I'll most likely be at R220-240k+ and that’s without the Tesla’s already built-in inverter. You also need an installer with LG Chem Installer Certification and I've only found the 6.5kWhunit locally but no pricing from SegenSolar who to date have not responded to email or phone calls - I might try again.
• DEYE – I’m hearing good things, but they are also expensive – R38k-R43k for 6.14kWh (R6.1-7k per 1kw vs R5.2k I paid) - in Fairness if you pair it with a DEYE inverter they extend your inverter warranty to 10 yrs from 5yrs to match the 10yr battery warranty,  in essence you're paying for the 5yr extra warranty on your inverter so this is looking like an option but only if I can get a higher capacity single module between 10-15kWh will I consider this Sunsynk which is DEYE vice versa have a 15.97 LFP wall mount unit for about R96k so that is priced in my opinion more inline but I'm not sure if you get the same inverter warranty extension for a DEYE inverter because you do get an extra 5yrs on the Sunsynk invert...

I’m not really interested in Hubble for personal reasons (but feel free to change my mind - also in the same boat with local is lekker - but I see that actual capacity seems to be questionable), anything with ESS in the name – I think CFE and few others are all the same 5.12kWh battery in fact wrongly or rightly so they’re unheard of in Europe, the US and Australia, both large markets for Batteries, which aren’t accepting inferior LiFePo4 and the like batteries onto their shores and we should be asking ourselves why.

The Only exception here is AlphaESS which SolarAdvice use to carry but no longer do and in hindsight while I was told the systems cannot be paralled to each other the 5kWh/10kWh Storage & Inverter Combo Smile5, is well documented and supported in Australia, Singapore and in some parts of Europe and the paralleling issue can easily be worked around by creating separate 5kW circuits and running separate subsystems - if I had to do it all over again which I cannot afford to do now, I would go this route because I have an honest Sparky and that means I would have split my solar array into 4x 2.025kw Arrays (2xMPPT per inverter) feeding 2 separate 5kw circuits with 20kWh of storage between the two and cost wise, would have come out about the same as my 8kw Inv. 20kWh(eventually) storage and 8.1kw Solar Array - However, I wouldn't attempt this type of setup with the majority of unscrupulous 'electricians/installers' I have had the displeasure of dealing with over the years.

Rant over - For now...

 

 

 

The Sunsynk is the british/ eu western brand for deye, Deye anounced that after 10 years they will replace a faulty cell obviously courier not included. 

I Whole heartedly agree with your cfe results and statments same experience multiple sites,

deye batteries are almost drop-in for GLA's but the reliability is excelent.

 

According to CFE the SOC problem has been sorted with the new software. We usually buy bulk but try and stay away. The price is very good at the volumes we buy but cannot go back to fix. We are currently moving more to the better units than the cheaper like Deye, volta pro [also a deye manufactured batt] and have hundreds of shotos in the market.

 

Any reviews since the software update?

On 2023/06/20 at 5:33 PM, TheMafiaMan - NotMuffinMan said:

Welcome @New

As you can see I've not had a great experience - your SOC cycling between 90-100 suggests 2 firmware version earlier than mine now after 2 updates - mine did that originally - purchased in Nov 2022 you can see in the post how to determine which batch and version battery you have but if you bought it in the last 3-6 months its the v3 most likely - mine is too.

My advice - don't update the firmware if you're not having any issues - I hope unlike me time doesn't paint a different picture - if you can get below a 20% SOC then you're already better off than I am, whenever my batteries hit 40% SOC they'd drop to 7/5/1% in 2-3 minutes.

Maybe as a caution, C rating doesn't stack as people think it does - I've seen multiple installers, resellers etc. say that 2 x 0.5C batteries gives you 1C. That is not correct. Assuming you have 1, 4 or 8 of the same battery rated at 0.5C your storage capacity is doubled, quadrupled etc. but in essence if you want to realise that stored energy as efficiently as possible then you would need to use it at 0.5C or even possibly 0.25C

Basic rule" C rate doesn't stack in Series

In parallel connection the C rating is wrongly attributed to stacking the load because you're "1/2 ing" the current between for example 2 batteries - think of it this way the faster you discharge them "Higher C rating" the less electricity you get out over time.

At it's simplest Its the electric car example - lets use a TESLA - freekin quick but if you thrash it in 01-100 launches and max performance pulls what happens - batteries overheat and your range i.e. usable storage disappears and becomes much less. fast = more power, more power = higher C rates 2C, 4C 8C etc.

I used to in a previous life fly large commercial load-bearing drones - we'd have large LIPO packs that you could pull/discharge at 25-40C for about 2-3min in specialty situations and then they'd unceremoniously die or you could fly reasonably at 8C and get 10-12min

If you where unlucky your drone would plummet out the sky or if you where a good pilot you'd monitor voltage and current like a naughty kid in a park and landed it just before it was about to expire - I was one of those pilots that was careful and I have only ever lost one drone - I "infamously" drowned a very large, very expensive drone 10yrs ago that had a faulty BMS and I ignored the V and C rates for 5-10 seconds - it landed itself in a large dam - police divers had to come fish it out. Needless to say my "employers" where not happy with me - however telemetry data proved I wasn't reckless and that the BMS went "offline" about 15seconds before the drone became "unstable" - the lesson applies though.

200AH batteries discharged at 2C will not nett you 200AH worth of energy.

CFEs own data is misleading - an older manual states 5000w/3000w nominal i.e. 0.6C, the sticker on the side says 100ah or 1C and newer docs mention neither other than 1C charge and discharge - they cannot seem to decide which one - I would have to advise based on my experience that you treat them as 0.5C for charging and discharging.

My beef with them is CFE sell there batteries as 1C charge and discharge product - It cannot in my case reliably do 1C between the 2x 5.12kWh batteries and in Lithium mode the batteries die in 17min or less - now whether the SOC is wrongly calculated, comms are faulty or my batteries are not charging fully or discharging, I don't know, but we cannot spend the type of money we do on these to tinker - If I wanted to do that I'd build my own battery packs.

My advice after 7+months - there is no need unless a once-in-a-blue-moon emergency to charge your batteries at 1C - 100AH, i'd recommend not acceding 0.5C or 50A and I found 40A is a nice middle ground leaving your inverter some headroom to run other loads when charging - again ideal on a 8kw invert but I'd drop that to 20-25A on a 5kw inverter.

Did you eventually get sorted out with the cfe battery and their technical contact who offered support above?

I'm wondering the same thing, we have issue like that also.

Or did the CFE Mafia got rid of TheMafiaMan?