Pylontech Firmware Updates (We Take No Responsibility For Any Firmware Posted Here, Choose Correct Firmware For Your Battery)

Are you sure that voids warranty? Something to ask about. I’m sure a few high voltage events that were caught by the BMS (as it should) would not automatically repudiate a warranty claim.

All I can think is to discharge the battery until it says it is empty. If possible, measure the energy you get out of it, but also okay if not possible.

If there is a damaged cell, I expect that you will get a “drop off a cliff” moment. The BMS is counting Amp Hours as they leave the battery, registering a gradual drop in SOC… but then as one cell suddenly drops sharply in voltage it will drastically amend its SOC estimate, causing a steep drop in the curve.

Wherever you see that drop, the difference between that and 100% is the new capacity.

If you don’t see a drop… then simply giving it some time to balance should set it right.

Look for any signs of swelling of the battery case. If swollen I would remove it immediately from your battery bank and contact PylonTech for a warranty claim.

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+1 on that. E-mail the BatteryView logs to and ask what to do. On the rare occasion that I’ve had issues their service has been excellent. A couple of weeks ago one of my batteries (3.5 years old) started throwing the occasional cell imbalance error and they swapped it out for a brand new one.

Edit: Corrected Pylontech e-mail address

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Thanks for the suggestion. I’ve tried sending them the logs and the history of this install but the mailbox refuses my mail: failed after I sent the message. Remote host said: 550 Mailbox unavailable or access denied

Later Edit: I’ve sent the mail to service@ and it went through. The gist of it is that the log shows very minor PHV/POV events registered before 08.2020 before I lowered the max charging voltage from 54V set by installer to 52.5V but the battery pack was healthy. In fact it was event free for almost 2 years until mid 2022 when BOV events started to show up, first with moderate values of 3.75 then progressively worse and in 2023 I can see maximum cell values of over 4V suggesting at least a cell with progressively increased internal resistance, probably damaged.

Ah yes, sorry, that was my bad. I’ll edit my post to the correct e-mail address.

After all this time (and a repeated email submission) I got a reply from PYL instructing me to:

  • Update firmware
  • Charge modules separately to 100%
  • reconnect the stack and report back if still imbalanced

After firmware update to v3.4 for us2000b plus the imbalance was still obvious even with the improved algorithm trying to match discharge rates to remaining capacity. Pylontech service analyzed the logs and concluded there is a defective cell and honored the warranty!

Pylontech service is indeed excellent, I humbly admit that wasn’t expecting this result: they’ve sent the RMA to the distributor who got in contact with the local reseller and now I need to integrate a US2000C to the stack!

Just for reference, the defective pack had obvious swelling showing through the bottom metal sheet. Not immediately evident in a picture but quite evident with the naked eye and by running the hand across the surface


Hello Jaco

Would it be possible to send me the special programme, because unfortunately I have also damaged my Pylontech 3000C with a wrong update.
Thank you very much, Richard

I have send you a pm

Hi Jaco

Please can I also receive the Magic program or advice -

I have updater UpgradeTool V1.0.9 and the the latest?, however I dont get the US3000C in bootloader mode.

I kicked the cable during the upgrade and lost the connection, now no lights nor a response from the US3000C, even if I do the Power Switch while holding the Red button sequence. (Edit - I do get it to Connect about 1 out of 15 times, see below)


When I do get the Updater to connect (1 out of 10 times), the program gave this back when clicking on Program after it said Connected.

MOST IMPORTANT RULE for firmware upgrade/update: IF IT AIN’T BROKE DON’T FIX (if you have to get professional to do)

Dead Pylontech- How to bring pylontech back to life after corrupt or failed firmware update setp-by-step

1.Confirm the dip switches are 1-0-0-0 with battery off
2.Plug in debug cable/firmware upgrade cable
3.Run Upgrade Tool
4.On Upgrade Tool make a tick by immediate update and then click connect (should say connected)
5.Click on browse to .bin file and choose (HAS TO BE .BIN NOT .ZIP FILE) for me nt.bin one worked
6.Press “program” on Upgrade Tool
7.Quick switch on battery (hold the red button in and then switch on the main switch, you can release the red button after switch on)

Upgrade Tool should say Get in bootloader mode
Upgrade should load and battery should switch back on (if not start again from step 4)

My mistake I unzipped firmware when using BatteryView to upgrade
DO NOT unzip firmware file for BatteryView Upgrade (region settimgs on PC must be United States)

Hope this helps/makes someones life easier coz it took me a while to figure out

Hello Jaco. I’m new to the group and I wanted to ask you a question about that “back door”.
I have a US3000C battery that was at version 1.4 and I updated it to 2.1 successfully. The problem was when trying to update it to version 2.8.
The program crashed at 80% and the battery has stopped working. No lights come on.
Do you know how I can solve it?
Thank you so much.

What version of BatteryView did you use and where can I get it? When I search I can only find V3+ downloads.

Hello, can someone send me the latest firmware for US5000C and any files needed to upgrade from older firmware (incase there is stepped firmware required).

Thank you

I followed the instructions to upgrade my us2000c. Stuck at 83%. Now cant connect to my battery again. Wont boot up. Any help would be appreciated

Hi Jaco I’m looking for the latest battery view software for the Pylontech batteries. Do mind sharing the software with Me. The link further down doesn’t work. Give an error.

Hi Jaco

I upgraded my pylontech us2000c and its bricked. Is there a way of software i can use to unbrick my battery.

Im a tight budget and cannot afford to loose this unit…

Kind Regards
Quintin Sleeking