Sonnen BMS?

Hey All -

I have 2 Sonnen nDure LFP2 2.5kwh battery packs which I'm trying to repurpose, without their $10,000 cabinet/inverter system....I got these packs for free.
There is not a lot of info about what these packs use to communicate, whether it is proprietary communication, or if there is an exterior controller out there.
Sonnen wont tell me if it is something that we can access with a 3rd party device.

There are 2 comm ports
RS232 "For Laboratory Diagnostics" per the manual
Controller"Used for BMS HomeRun cable" - per the manual (goes to their SPREE controller, main controller for Inverter/battery interface)
2 Link Ports for linking the batteries together
Its not clear if the management is done on each pack locally, and the SPREE is just a Gateway/Controller for the Batts and the rest of the system, or if the SPREE is actually the brains, and the packs just have the necessary circuitry for sensing the cell voltages/Ah. I believe that the packs have Onboard BMS.
So, i'm looking for a way to manage/monitor the battteries adequately. I see all sorts of BMS online if you are building your own pack, but nothing that just communicates with the onboard BMS.

Where should I start here? Pull open the case to see if it has onboard BMS? Is there an inexpensive controller someone would recommend that I just plugin and start playing around with? At the end of the day, i don't have much dough sunk into this project at all, so if I brick the batteries, or melt them on my bench(which is detached from my house ;-), i'm a little sad, but not heartbroken.

More details on the packs in the attached images.

Thank for any help y'all might have.

Note the charge voltage of 53.5. This is a 15S battery vs. the typical 16S battery for 48V. You will need to locate a 15S LFP (3.2V) BMS if the unit doesn't have one internally.

sunshine_eggo said:

Note the charge voltage of 53.5. This is a 15S battery vs. the typical 16S battery for 48V. You will need to locate a 15S LFP (3.2V) BMS if the unit doesn't have one internally.

Click to expand...

Nice, that is great to know, i noticed the P/N/spec at the top contains 15S2P, so there are 2 parallel strings in there.....

I just got 3 almost the same as yours but black. I popped the cover and found 3) 16 volt 50ah battery packs connected in series. There is a bms inside already and each pack has its own balance leads. I don't have any 48 volt charger/inverter so I'm considering opening packs to make 12/24 volt packs but would need to buy new bms. I really don't want to tare it apart just because it is in new condition and never used. Might just have to bite bullet and by a growatt inverter charger. It should connect rather easy and I got an extra 400 watt solar panel.

@nicthegr - did you happen to take any photos while you had the cover off? they have a couple different models, but the Ndure(white) and the black one's you have, are almost identical, wondering if the BMS/guts are the same as well. i will PM you some pics in the next few days when i can tear off the cover, maybe we can come up with something and share the knowledge.

Sonnen is in the dumps with their "ECO" lines which are basically an (otherwise fine)outback radian with some malfunctioning brains and a transfer switch attached. I might have access to a few more units which sonnen has deemed 'defective' but probably otherwise have some good cells in them, and there should be some used

Cheers -

nicthegr said:

I just got 3 almost the same as yours but black. I popped the cover and found 3) 16 volt 50ah battery packs connected in series. There is a bms inside already and each pack has its own balance leads. I don't have any 48 volt charger/inverter so I'm considering opening packs to make 12/24 volt packs but would need to buy new bms. I really don't want to tare it apart just because it is in new condition and never used. Might just have to bite bullet and by a growatt inverter charger. It should connect rather easy and I got an extra 400 watt solar panel.

Click to expand...

---

SolMule said:

@nicthegr - did you happen to take any photos while you had the cover off? they have a couple different models, but the Ndure(white) and the black one's you have, are almost identical, wondering if the BMS/guts are the same as well. i will PM you some pics in the next few days when i can tear off the cover, maybe we can come up with something and share the knowledge.

Sonnen is in the dumps with their "ECO" lines which are basically an (otherwise fine)outback radian with some malfunctioning brains and a transfer switch attached. I might have access to a few more units which sonnen has deemed 'defective' but probably otherwise have some good cells in them, and there should be some used

Cheers -

Click to expand...

Did any one have any luck repurposing these batteries.?

I have been given 2 x 2.5Kw Sonnen batteries which I have added to my Growatt battery system. Problem is they don't stay on!

My Growatt batteries are connected to Growatt inverters and Communicate perfectly. The Sonnen Batteries have all the same ports but Imagine the protocols are different. I don't need communication with the inverters and the Sonnen batteries, they turn on fine and can measure 48V between the contacts but they don't stay ON for more than 5 mins. Think they need a signal to stay ON.

Any Ideas?

Same problem here, we need to use some kind of keep alive communication with a bmu but I can’t find one that will work. Did any one else fine one?

I'm late to the party but I bought 3 Sonnen 2.5kWh batteries. They are the "Sonnen Ndure". Today I cracked the RS232 port but there are no commands to make it stay on. Still good information though. This weekend I will crack the CAN BUS. Meanwhile I parallel two wires of the power button and made my micro-controller keep restarting it every 10 minutes 2 seconds. This is a funky way to run it but it worked for today. It allowed me to charge the unit which had a initial voltage of 49.1 volts. Will post pictures from my Ipad shortly.

I only had the 3 Sonnen batteries a day and I’m happy with my progress. I know a little CAN BUS protocol but I have a friend that is deep with it….may have to call in the big guns. But one way or another soon these 3 units will be on my powerwall.

SolMule said:

Hey All -

I have 2 Sonnen nDure LFP2 2.5kwh battery packs which I'm trying to repurpose, without their $10,000 cabinet/inverter system....I got these packs for free.
There is not a lot of info about what these packs use to communicate, whether it is proprietary communication, or if there is an exterior controller out there.
Sonnen wont tell me if it is something that we can access with a 3rd party device.

There are 2 comm ports
RS232 "For Laboratory Diagnostics" per the manual
Controller"Used for BMS HomeRun cable" - per the manual (goes to their SPREE controller, main controller for Inverter/battery interface)
2 Link Ports for linking the batteries together
Its not clear if the management is done on each pack locally, and the SPREE is just a Gateway/Controller for the Batts and the rest of the system, or if the SPREE is actually the brains, and the packs just have the necessary circuitry for sensing the cell voltages/Ah. I believe that the packs have Onboard BMS.
So, i'm looking for a way to manage/monitor the battteries adequately. I see all sorts of BMS online if you are building your own pack, but nothing that just communicates with the onboard BMS.

Where should I start here? Pull open the case to see if it has onboard BMS? Is there an inexpensive controller someone would recommend that I just plugin and start playing around with? At the end of the day, i don't have much dough sunk into this project at all, so if I brick the batteries, or melt them on my bench(which is detached from my house ;-), i'm a little sad, but not heartbroken.

More details on the packs in the attached images.

Thank for any help y'all might have.
View attachment 81607
View attachment 81606

Click to expand...

I just got 3 of them yesterday $800 USD. They are a little different but the PYLONTECH BMS, will be cracked…..guaranteed.

sunshine_eggo said:

Note the charge voltage of 53.5. This is a 15S battery vs. the typical 16S battery for 48V. You will need to locate a 15S LFP (3.2V) BMS if the unit doesn't have one internally.

Click to expand...

Or used the BMS that comes with the unit. It‘s made by PYLONTECH and it’s a nice BMS.

magnathea said:

---

Did any one have any luck repurposing these batteries.?

I have been given 2 x 2.5Kw Sonnen batteries which I have added to my Growatt battery system. Problem is they don't stay on!

My Growatt batteries are connected to Growatt inverters and Communicate perfectly. The Sonnen Batteries have all the same ports but Imagine the protocols are different. I don't need communication with the inverters and the Sonnen batteries, they turn on fine and can measure 48V between the contacts but they don't stay ON for more than 5 mins. Think they need a signal to stay ON.

Any Ideas?

Click to expand...

Just got 3 Sonnen’s yesterday did you solve the timing out issue? I will be looking into that port labeled “controller“ this weekend. I already cracked the RS232 Port, it gives a lot of information but no command to make it stay on. The Sonnen Ndure model stays on 10 minutes before timing out.

SolMule said:

Hey All -

I have 2 Sonnen nDure LFP2 2.5kwh battery packs which I'm trying to repurpose, without their $10,000 cabinet/inverter system....I got these packs for free.
There is not a lot of info about what these packs use to communicate, whether it is proprietary communication, or if there is an exterior controller out there.
Sonnen wont tell me if it is something that we can access with a 3rd party device.

There are 2 comm ports
RS232 "For Laboratory Diagnostics" per the manual
Controller"Used for BMS HomeRun cable" - per the manual (goes to their SPREE controller, main controller for Inverter/battery interface)
2 Link Ports for linking the batteries together
Its not clear if the management is done on each pack locally, and the SPREE is just a Gateway/Controller for the Batts and the rest of the system, or if the SPREE is actually the brains, and the packs just have the necessary circuitry for sensing the cell voltages/Ah. I believe that the packs have Onboard BMS.
So, i'm looking for a way to manage/monitor the battteries adequately. I see all sorts of BMS online if you are building your own pack, but nothing that just communicates with the onboard BMS.

Where should I start here? Pull open the case to see if it has onboard BMS? Is there an inexpensive controller someone would recommend that I just plugin and start playing around with? At the end of the day, i don't have much dough sunk into this project at all, so if I brick the batteries, or melt them on my bench(which is detached from my house ;-), i'm a little sad, but not heartbroken.

More details on the packs in the attached images.

Thank for any help y'all might have.
View attachment 81607
View attachment 81606

Click to expand...

I know, I’m late as hell to the party but I got it! Send all zeros to CANBUS ID 0x4200 every second or two. I used an old Raspberry pi 3 for my CANBUS
import RPi.GPIO as GPIO
import can
import time
import os


led = 22
GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(led,GPIO.OUT)
GPIutput(led,True)

count = 0

print('\n\rCAN Rx test')
print('Bring up CAN0....')

# Bring up can0 interface at 500kbps
os.system('sudo /sbin/ip link set can0 up type can bitrate 500000')
time.sleep(0.2)
print('Press CTL-C to exit')

try:
bus = can.interface.Bus(channel='can0', bustype='socketcan')
except OSError:
print('Cannot find PiCAN board.')
GPIutput(led,False)
exit()

# Main loop
try:
while True:
GPIutput(led,True)
msg = can.Message(arbitration_id=0x4200,data=[0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00],is_extended_id=True)
bus.send(msg)
time.sleep(.5)
message = bus.recv()
print(message)
time.sleep(.4)
GPIutput(led,False)
time.sleep(.1)




except KeyboardInterrupt:
#Catch keyboard interrupt
GPIutput(led,False)
os.system('sudo /sbin/ip link set can0 down')
print('\n\rKeyboard interrtupt')