Dæv

Hi guys,
I've realized that my first Pylontech battery will be 6 years old this March, so I've pulled some stats on the SOH and Cycles to share together with my thoughts.
CC = 52.5V
CV = 52.5V
8x US3000
System SOH : 96 % Power Volt Curr Tempr Tlow Thigh Vlow Vhigh Base.St Volt.St Curr.St Temp.St Coulomb Time B.V.St B.T.St 1 50955 -260 23000 20000 21000 3390 3399 Dischg Normal Normal Normal 100% 2025-01-30 22:16:53 Normal Normal 2 50965 -256 23000 20000 21000 3390 3400 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal 3 50970 -260 23000 20000 20000 3392 3402 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal 4 50948 -252 23000 20000 20000 3387 3399 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal 5 50969 -256 23000 20000 20000 3389 3399 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal 6 50975 -262 22000 20000 20000 3392 3400 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal 7 50959 -268 22000 19000 19000 3391 3399 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal 8 50945 -260 21000 18000 18000 3388 3398 Dischg Normal Normal Normal 100% 2025-01-30 22:16:52 Normal Normal CYCLE Times : 267 CYCLE Times : 518 CYCLE Times : 521 CYCLE Times : 523 CYCLE Times : 529 CYCLE Times : 520 CYCLE Times : 511 CYCLE Times : 501  
8x US3000C
System SOH : 98 % Power Volt Curr Tempr Tlow Thigh Vlow Vhigh Base.St Volt.St Curr.St Temp.St Coulomb Time B.V.St B.T.St MosTempr M.T.St 1 50890 0 22100 19900 19900 3387 3396 Idle Normal Normal Normal 100% 2025-01-30 23:52:12 Normal Normal 20600 Normal 2 50903 -203 22300 19900 20200 3378 3397 Dischg Normal Normal Normal 100% 2025-01-30 23:52:10 Normal Normal 21000 Normal 3 50897 -256 23300 19700 20100 3386 3396 Dischg Normal Normal Normal 100% 2025-01-30 23:52:08 Normal Normal 21300 Normal 4 50906 -256 22300 18900 19300 3386 3396 Dischg Normal Normal Normal 100% 2025-01-30 23:52:08 Normal Normal 20600 Normal 5 50895 -258 22000 19000 19400 3385 3395 Dischg Normal Normal Normal 100% 2025-01-30 23:52:08 Normal Normal 20200 Normal 6 50896 -266 21900 18300 18600 3385 3397 Dischg Normal Normal Normal 100% 2025-01-30 23:52:08 Normal Normal 19900 Normal 7 50896 -260 20900 17900 18200 3386 3395 Dischg Normal Normal Normal 100% 2025-01-30 23:52:08 Normal Normal 19200 Normal 8 50901 -264 20600 17100 17500 3387 3397 Dischg Normal Normal Normal 100% 2025-01-30 23:52:08 Normal Normal 18900 Normal 9 - - - - - - - Absent - - - - - - - 10 - - - - - - - Absent - - - - - - - 11 - - - - - - - Absent - - - - - - - 12 - - - - - - - Absent - - - - - - - 13 - - - - - - - Absent - - - - - - - 14 - - - - - - - Absent - - - - - - - 15 - - - - - - - Absent - - - - - - - 16 - - - - - - - Absent - - - - - - - CYCLE Times : 140 CYCLE Times : 141 CYCLE Times : 246 CYCLE Times : 233 CYCLE Times : 240 CYCLE Times : 249 CYCLE Times : 249 CYCLE Times : 247  
At a first look, it's not that bad with 96% SOH on a 6yrs old battery. But on the other hand, it's been 4% down for just roughly 500 cycles it made in that time. If linear, then after around 2500 cycles made in total, it will be at 80% SOH. If 500 cycles took me 6yrs then after 2500 cycles done in total the battery will be 30 years old. No way the battery will last for that long. Based on this, I would say that the battery will die of age well before it dies on cycles.
What do you think?
Youda

Pylontech US3000 after 6 years of usage:
 

Regarding the Pylontech firmware...  First up, thanks for this thread.  It is without doubt the most useful resource on the internet relating to the issues discussed.
So... I had the issue with the Victron GX + <v1.7 f/w on a couple of my US3000Cs - the misreporting of a voltage spike in one cell causing the Victron GX to panic and shut that battery down.
I emailed Pylontech with a plot of the Vhigh readings (it would shoot to 4.1v for one reading, then back down again).  They responded very promptly (on a Sunday night, too) with a link to download a zip containing 'BatteryView 3.0.33' and a firmware zip file named 'USC_st2.8+NT2.2.zip', contained two binaries named 'US_E2_V2.2_Crc.bin' and 'US_C_V2.8_Crc.bin'.  Good so far.
Then the real fun started...
Couldn't get 'BatteryView' to connect, despite no problems accessing the serial terminal and getting appropriate responses from the batteries.
Tried 'Batteryview' under wine/mono in Linux Mint 21, build a Windows 10 VM, fully updated it, installed Win 10 natively, updated that, .NET 4.8.1, tried every combination of v 3.0.28 through 3.0.33, 3 different USB/RS232 interfaces...  Wouldn't connect, but terminal was fine.
Eventually did a native install of Win 11, same deal... Updated that (which took the best part of a day on a 40Mb/s fibre line) and finally, finally 'BatteryView' connected.  Downloaded all the 'history' and 'event' data, went to update the firmware on the first battery (according to the instructions provided by Pylontech, using the zip file) and...   it threw an 'unknown exception' error and just quit. 😭
OK.
Took a step back, sat down with a cup of tea and thought 'lets have a look at this firmware zip file'.  The one that 'thou shalt not unzip, least ye bricketh the unit'.  Re-read this thread, then thought that if I can work out which of the two bin files, maybe try that?  I mean, who's gonna know, right?
And lo, it came to pass that I could not unzippeth.  Because the %&*$!£ zip-within-the-zip was corrupt.  Re-downloaded from the source (wetransfer.com), same.
Came back here and grabbed the v1.8 zip, all 7 units are now updated fine. 🥳
 
So basically, a massive 'Thank You' to Youda and all who have contributed to this thread.  I hope the above contribution to it might prove useful to someone else facing similar issues.
Now I can hopefully sleep easy, or at least sleep without VRM waking me up with an email at 3.23am to inform me in panicked, breathless tones of some expensive-sounding 'internal failure' or 'cell imbalance' in battery 7 that means you have to get up and shuffle downstairs to silence the beep-of-doom and check that nothing's actually on fire. 🙂

Although I'm using Pylontech personally, there were two major objections that I had:
Thin cables was the first. My second objection was 15S arrangement of the cells. Speaking of amps, it's not just about cables. There are two internal passthroughs in each Pylon brick and SurLok 5.7mm version also has it's limitation (120 Amps). Manufacturer clearly state, that if you want to pull more than 120A from your bank, then you should either split it into more smaller piles or connect it using 4 cables instead of 2. Personally, I don't like the 4 cables option, as it might create a slight imbalance when charging/discharging. So in my case I split the pile into the two smaller ones, 5+4 bricks.
In theory, Pylontech could use SurLok 10.3mm version on the product, which is rated up to 350A and ready to be crimped on a 95mm2 cable. But I perfectly uderstand why they went with the cheaper version:
Choice of 25mm2 cables generates nice savings on the lugs and on the copper. With the 8 bricks combined in a single pile, there's around 32 individual connections and the transitional resistance starts to build-up. Therefore, it does not make a sense to pull the theoretical maximum of 592A (8xUS3000) thru all these "resistors". No matter how thick is the cable, every unnecessary flexible connection is a bad thing. Given that the majority of residential installations are having just around 4 bricks, 120A should be okay for most of the customers. Like I said, I still think that Pylontech should use the bigger lugs and thicker cables, but I understand why they decided to go the cheaper way.

SOLVED: Pylontech + Victron = High Cell Voltage Alarm
Hi guys,
the problem shown above is a specific issue that is affecting only the combination of Victron + Pylontech, when using CAN communication between the Victron GX device and the Pylontech's BMS.
Root cause is something like this:
Most of the inverter manufacturers are using original Pylontech BMS CANbus protocol implementation, that is quite limited on the information it can provide about the cells. It focuses on SOC, current control and alarms mainly. Victron was the first one (AFAIK) to implement enhanced version of the BMS CANbus protocol. The enhanced protocol is able to report information about the state of individual cells, which is great for diagnostics.
For a shame, from time to time there's a voltage sampling error. Normally, this error is being eliminated by the BMS verification algorithm, so the battery as a whole is aware that it's just an error and stays calm. But when the enhanced protocol is used then the Victron GX device receives actual value (bad sample), will log it in the VRM, and might start to panic.
That's the reason, why this issue is affecting Victron installations only (AFAIK).
The issue is solved via Pylontech firmware update, where bad samples are automatically eliminated from being forwarded to Victron GX.
Hope this helps,
Youda

I did in fact contact Pylontech and got an answer 2 days later. cool response time!
They say its a "firmware problem and can be fixed easily".
For that, they send me  a file with batteryview 3.0x B1.1 and a firmware (US5000_st1.4+e21.6) file for the US5000 + instructions.
ill try tonight and report if it works.
M.

I'm really sorry @Luminous , but there's not much interesting to share. Just everyday's boring stuff.
For example, I had to clearly label the bays in my space-shuttle landing dock, as some (female) family members were not able to clearly understand where they should (NOT) park:

 
Based on the current situation in the world, I upgraded to the AirLock. You know, just in case something goes wrong:

 
And yes, I bought another rack cabinet, so if I will accidentally become a billionaire one day, I will not have a problem with storing some additional lithium for my LAB:

 

Given the increased distance, I've decided to upgrade battery cables too. Before, I used 50mm2 cables. Since I like to over-engineer things a bit, I went for CYA H07-VK 150mm2 cable and the appropriate cable lugs.
50mm2 and 150mm2 cable lugs mounted side-by-side:

 
After - rack with 7x US3000 installed:

There's one thing on the Pylontech products, that I don't like: The Amphenol SurLock terminals and cabling that's designed to stack up to 8 batteries together. Terminals are cool, but the cables are 4 AWG only. That could be okay for a couple of US2000 bricks, but I can't imagine to have 7-8 stacked US3000 bricks sharing a 4 AWG (20mm2) cable. Therefore, I ordered a spare set of SurLock cables, and wired first 4 bricks via 1st set of cables, while other 3 bricks are wired using 2nd set of cables. If I will do some upgrade in the future, my plan is to continue like that - use a single cable set per each 4 bricks, not per 8.
 
 

each battery has its own BMS and will only be able to measure the current it is delivering, what you are stating does not make sense, if you have a battery that can deliver 50A then that is what you tell the inverter, as the maximum current it may draw, if you add 2 more batteries in parallel, the same as the 1st, then your allowed draw is 150A (and tell the inverter thus) and if you now add another battery in parallel that can provide 100A, then your total has just moved up to 250A potential current draw, since the load and current should be pretty much spread over the, by now, 4 batteries and not 100% evenly, since the battery that can provide double the current than the other 3, should and would, presumably have a lower internal impedance and thus should and I'd imagine, would, carry 2/5ths of the load, whatever it may be, if you are consuming 50Ampere, then the 4th battery in this scenario should provide 20Ampere and the other 3 should provide 10Ampere each... the batteries are not drawn down in succession, but they all provide part of the power
 

Regarding SolarAssistant...

I have SA in a Raspberry PI 3. I got random connectivity issues, so I wrote an email to the SA support. After a hundred of tests, the issue was the raspberry pi power supply. (ALL THIS AFTER THE INVERTER BOARD CHANGE, IS A DIFFERENT ISSUE)
I had a random power supply (5v and 3A), so I bought the original one for my RPI3 (https://www.raspberrypi.com/products/micro-usb-power-supply/) It gives 5.1 volts of output.

Apparently the Raspberry got voltage drops for some reason, so the connectivity was freezing with the USB ports (inverter and battery in 2 different ports).
In your case, I'd buy the same original power supply and try.

Cheers

Sorry for my late reply.  I have some news:
- My local solar supplier doesn't understand a single word in English, so I had to directly write an email to Growatt.

- I'm based in EU, so I tried sending an email to the support email that appears in the EU website. Somehow they didn't reply. So I checked and in The Netherlands they also have another (amazing and lovely) support team.

- They requested lot of photos + screenshots + a long video with the proof of my issue. After that, they requested 2 new boards to the factory supplier (China). 2 weeks after, I received them (with Fedex, so I had to pay for the custom taxes, but is OK)

- I installed the boards (battery, solar DC input and inverter, all turned off). I just replaced these boards and turned all back on. And... ALL WORKS!!

- The USB connection (normal printer USB cable + RPI3 with SolarAssistant), AND also the BMS connection with my Pylontech US2000C batteries!! (Inverter config 05 - LI // 36 - L52 if you ask).

So... I cannot be happier. The support from The Netherlands office made a great work.

Best regards.

Hey!
 
Ye, my problem started in December 2022 when my SA was giving voltage errors. I changed out the power supply and didn't connect the dots in regard to the communication issues that then started. It was only recently when I swapped the power suppliers back to how they were that things returned to normal. I advised SA of the problem I faced and how it was resolved. 
 
Glad you're sorted too! 
 
J

Regarding SolarAssistant...

I have SA in a Raspberry PI 3. I got random connectivity issues, so I wrote an email to the SA support. After a hundred of tests, the issue was the raspberry pi power supply. (ALL THIS AFTER THE INVERTER BOARD CHANGE, IS A DIFFERENT ISSUE)
I had a random power supply (5v and 3A), so I bought the original one for my RPI3 (https://www.raspberrypi.com/products/micro-usb-power-supply/) It gives 5.1 volts of output.

Apparently the Raspberry got voltage drops for some reason, so the connectivity was freezing with the USB ports (inverter and battery in 2 different ports).
In your case, I'd buy the same original power supply and try.

Cheers

Sorry for my late reply.  I have some news:
- My local solar supplier doesn't understand a single word in English, so I had to directly write an email to Growatt.

- I'm based in EU, so I tried sending an email to the support email that appears in the EU website. Somehow they didn't reply. So I checked and in The Netherlands they also have another (amazing and lovely) support team.

- They requested lot of photos + screenshots + a long video with the proof of my issue. After that, they requested 2 new boards to the factory supplier (China). 2 weeks after, I received them (with Fedex, so I had to pay for the custom taxes, but is OK)

- I installed the boards (battery, solar DC input and inverter, all turned off). I just replaced these boards and turned all back on. And... ALL WORKS!!

- The USB connection (normal printer USB cable + RPI3 with SolarAssistant), AND also the BMS connection with my Pylontech US2000C batteries!! (Inverter config 05 - LI // 36 - L52 if you ask).

So... I cannot be happier. The support from The Netherlands office made a great work.

Best regards.

Thank you for that. Yes, they're all communicating with one another and the "master" is well communicated with the inverter, so I'm not worried about safe charging due this.

Maybe the max Ah is set to 37A given I have mixed different Ah batteries and they take this value for safety reasons (the BMS rules here hahahh).


----

Btw, I just wrote an email to Pylontech support ('sales' email but I cannot find other). I hope they can bring some light on this topic.

When it comes to batteries, adding another in parallel is a little more complex than just adding the currents. Depending on how the batteries are wired and whether there is a connection box between the batteries, your charging currents are going to be a little odd.
I am no PylonTech or Growatt expert, mostly work with other brands, but the theory should remain the same. The inverter should be doing a careful balancing act depending on the SOC of the battery and the power it's getting from solar. Things like source/charge priority also play a part in how charging currents are set by the inverter. 
My only real input here would be make sure the batteries and inverter are all communicating with one another. Usually I advise users avoid mixing different Ah batteries because it becomes a nightmare for safe charging, the BMS will definitely help though with a lot of it.

Hi have 3 Us3000c batteries and Solar assistant says recommended charge/discharge 37amp but if I look in the inverter settings it is changing as the state of charge changes. When Low COC it is normally 110Amps and will decrease when above 90%.

I had similar problem and found out that the supplied brand new USB printer cable was at fault. It worked fine with another spare cable. I understand that you already tried this. You could try with a RS232 to USB adapter cable. I guess that the RS232 cable (JR45) has been supplied.
If nothing works, it could well be a faulty communication board. It's relatively easy to replace. The seller should take care of it in guaranty.