Any Hybrid Inverters work with DIY batteries?

1.21 Gigawatts

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I want to build a 10+kw powerwall & direct DC couple to a hybrid inverter.
Aside from being more efficient (i believe), the inverter can manage the direction of power as needed (export to home/battery/grid), & i'll be able to easily keep track of everything via the inverters cloud monitoring.

Solax inverters for example already offer this kind of solution, but using their battery.
I imagine the tricky part is getting the inverter to talk to my BMS.
Is it possible to connect a DIY battery to any hybrid inverter?
I haven't purchased the inverter or BMS yet. I'm hoping i can find a compatible solution.
I would like it to be 3 phase compatible. Minimum 10kw inverter (ideally 15kw)

I wonder if its possible to buy the same BMS used by inverter company. then they should definitely talk to each other. Propriatary code may still be a problem tho.

Cheers for the replies.
 
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1.21 Gigawatts

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Just looking at the data sheet for the SolaX Battery
Says is uses CAN2.0 RS485
Does that help in matching the inverter to a compatible BMS?

solax batter data sheet.png
 

yasko

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@1.21 Gigawatts - Yes, It's possible to connect DIY battery to hybrid inverter, but it depends on the inverter and battery setup.
If we are talking about hybrid inverters with a LV battery there are some BMS solutions on the market, that can do the work. But you are referring to a three phase hybrid inverter (Solax) which requires a HV battery (minimum 180V). AFAIK there is no BMS that works out of the box for these inverters. The interface between the inverter and the battery BMS is CAN based, but the protocols are closed and proprietary.
I have some success with Goodwe HV hybrid inverters and you can check this topic.
What type of batteries do you plan on using? A simple calculation for 10kW output, gives a battery with nominal voltage of 400V...
 
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1.21 Gigawatts

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@yasko Wow, just had a look at your thread, impressive bit of hacking/reverse engineering. I'll ask some related questions in your thread. Sounds though like i have to take a gamble on buying the inverter and hoping a can find a way if i go with Solax.

What type of batteries do you plan on using?
As the battery isn't built yet, so i can configure as needed, but was planning on using 18650 cells. Im open to using other battery chemistries & form factors if advantageous to do so. Im really at the start of this journey.

The SolaX 'triple power' battery is LFP with a nominal voltage of 115.2V (operating voltage of 100v-131v).
To match that, I would need to build a 32s 39p 18650 battery. From my understanding <120V DC is classed as LV in Aus. If i built a HV battery I think I'd need an electrical license to connect it (still not 100% clear on the laws, need to do more research).

The solax X1 single phase inverter data sheet lists a voltage range of 85v to 400v.
However the X3 three phase inverter, data sheet lists a battery range of 160v to 800v, which is a higher minimum than the 115v a single 'triple power' battery provides. Their batteries stack in series up to 4, so I'm guessing their X3 inverter requires a minimum of 2 batteries in series.

Reading the X3 user manual, I've discovered the inverter can work with "Pylontech batteries" and its a 48V battery!! Very interesting... I also found the "BMS pin definition".

solax hybrid 3 phase bms pinout 3.png



Step ONE, on i imagine a long road. Would be great to work with someone of your caliber to figure this stuff out :)
 
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daromer

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MPP 10kW MPI series inverter is Hybrid and does it. But its not efficient. 180-240w idle useage. Ie 80w per phase.
You can check below since i use that.
 

yasko

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Wow, an MPP10KW inverter is running at 48V, which is more than 200Amps. I can't imagine the wire size.

@1.21 Gigawatts I would recommend using large size batteries, preferably LiFePO4 chemistry. Battery modules from EV battery (or whole battery) are a good option too. In some cases, it's possible to re-use the original BMS. Building an HV battery with 18650 cells sounds a little risky unless you make it from separate modules. Each module max 14-16S with its own BMS and then connect them in serial. Most commercial systems are made in this way and the Pylontech battery referred by you uses that design. Each module is nominal 48VDC with integrated BMS, and there is a master BMS which control slaves and communicates with the inverter.
There is one limiting factor with these HV battery inverters - maximal discharge current. It's around 20-30A, so if you need high output power, you have to use a higher voltage. That explains why the Solax X3 inverter is rated 800VDC max at battery input. If you want to pull 10kW, that is a battery with a nominal voltage of 400V. In this case, you will need eight 48V modules or at least 108S configuration if you go with 18650 cells.
Whatever you chose to be careful, any voltage higher than 48VDC is considered dangerous.
That is a new and interesting topic I will be glad to discuss different architectures and solutions.
Regarding your inverter choice, I'm not familiar with Solax inverters, and no 100% sure it can work with DIY batteries. It depends on what batteries are supported.
 

prepared1

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1.21 Gigawatts:

Yasko makes some very good points in his reply.

I don't want my reply to sound like bashing you, because I have been examining the same thing for years. That being said, based on your initial post, just the fact that you don't know the answer to the question you posed should cause you to seriously question why you want to do this, and whether or not it is safe. There are many, many examples of inverters that are available like the one you mention, or batteries that were constructed to work for a specific application, and with certain protocols. Is it FEASIBLE that it could be made to work? Yes. Is it likely? DOUBTFUL. Does it requires communication back and forth between the inverter/car/computer/remote computer/battery.....PROBABLY.

I initially had a love affair with the Honda Fit LTO batteries. Bought a bunch of them. There are aficionados of the original Honda hybrid that re-purpose those packs, and there are some brilliant people working to crack the code on the factory BMS. And, they have had some success. I've even corresponded with some of them. But they generally need to get paid to do that kind of work, and it just makes it next to impossible to get the job done, unless you are personally able to do it. And, when people started to see the possibilities, those LTO batteries disappeared over-night.

Signature Solar in Texas has crap loads of really great Delta inverters that came from the solar company Tesla bought out...designed to work with a specific early version of the Powerwall. Same story as you describe...I really wanted to find someone to work with to crack the communication between a high voltage battery, and those inverters. The inverter is worth buying just as an inverter only, but it is such a shame to not use the battery part of the equation. Meanwhile, there are reams of new inverters coming out that are more powerful, more efficient, lower start up voltage for MPPT, etc. And battery technology is changing like crazy too.

Just a short rant, and word of caution: don't forget that you are literally taking your life into your hands when you work with batteries, or DC in general. I cringe when I see popular YOUTUBE videos of guys walking around in their shop with a baby or toddler in a back-pack , or said toddler having access to power tools, a wrench, cutting tools, etc. It may be "cute", but all it takes (literally) is throwing one wrench into the works to cause a horrendous accident.

Back to your topic...keep in mind that the goal of companies like Victron, Tesla, etc is provide a revenue stream to keep themselves in business and make a profit. Some do it by partnering with battery companies to offer a packaged solution, and it works to their disadvantage to make it easy to modify their products for another use, or to work with other companies products. Of course, there is also a huge liability issue involved. So you won't get support from them. What is left are people who have the knowledge, experience, drive, money, etc to DIY their own systems.

Personally, I'm not able to crack those codes, and make those products work seamlessly in a system. But wait a few years, and technology will do it for us. In the meantime, I'm having a good time working with ESS and car modules to build backup systems for power outages. Maybe I can find a guy to team up with who is a wiz with the technical/communication side.

Best of luck with your project.
 

jaldwt

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Reading the X3 user manual, I've discovered the inverter can work with "Pylontech batteries" and its a 48V battery!! Very interesting... I also found the "BMS pin definition".
Hello all,

Gigawatts, this is not correct: the pylontech battery is a HV model, not the 48V as you say.

My friend, be careful with this kind of setup, HV batteries are very dangerous. For HV, go for something already in the market.

I was considering to create something with an Goodwe GW6000 as yasko did (great work btw), because of the price of the inverter, the high output power, and the possibility of using a EV battery and use it's CAN interface. In this case we save a few bucks...

But for safety proposes, i will go with the LV option, with two GW5048D-ES in parallel.

Last note, if you are interested in Solax inverters, be aware, they will send to market very soon the X1 Hybrid G4. That's why some stores are lowering the prices of older versions.

Sorry for my English...
Regards from Portugal.
 

daromer

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200A is not a lot. That's basically what you have in household main centrals for houses running single phase 110v ;)
I use 70mm2 cables from the battery bank and the losses are not to talk about. Compared to what the Inverter uses and looses when converting.
 

Araknid

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I have a Solax X3 hybrid inverter that I want to hook my own BMS to...

I’ve had a few email requests to Solax for information on either rs485 or the canbus spec, but no success yet.

The Pylontech power cube X is the HV battery . It’s a BMS unit with slave 48V shelves in series. The main controller takes RS485 from what I can gather and this spec isn’t public.

The other HV battery they co develop uses a canbus network to synchronise multiple battery stacks in parallel. So there is a can spec somewhere for this.....

IF someone has a running system we , me, could sniff the canbus and workout the init and runtime spec.... just need someone with one :)

or buy a single BMS and smallest battery to work it out :) I’ve logged two messages off th canbus so far which I’m guessing are a wake up request to the battery units. A fairly bland extended ID message with a 1 and few zeros :) I can only post that message later if you like?

so with Solax it’s either emulate a pylontech powercubeX or their other brand. The low voltage canbus crap for LG resu-10LU doesn’t work... obviously.. I tried
 

yasko

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@Araknid, I've just checked your FoxWall-HV project. Impressive work!
The inverter (GW6000-EH) that I'm working on also supports the Pylontech power cube X battery. I don't have one but have some ideas about reversing the protocol :) Can you post place a CAN messages from the inverter?
 

Araknid

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The truepower batteries use canbus and the Pylontech uses rs485.

the solax inverter throws this out every second


***<Time><Tx/Rx><Channel><CAN ID><Type><DLC><DataBytes>***
11:16:01:7273 Rx 1 0x1871 x 8 02 00 01 00 01 00 00 00
11:16:02:7272 Rx 1 0x1871 x 8 01 00 01 00 00 00 00 00

I haven’t logged the rs485 connection yet.
 

Araknid

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ok check out https://powerforum.co.za/topic/2322-youdas-off-grid-lab/page/3/ this has a package called BatteryView which must be a PylonTech tool.. IIIIfffff you used this to find out what its asking the SC0500 and HD48050 system, then you (we) could emulate that interface .. I think the SC0500 interface is what the solax inverter already knows to talk to.

Its either the SC0500+HD48050 stack via rs485 or the TruePower HV battery via can-bus
 

yasko

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I've checked my inverter and turnеd out to support Powercube H1 battery, based on the main controller SC1000-100S and 4-8 H48050 slave modules. It uses CAN bus communication with the inverter.
Maybe it's different from Powercube X1 because I got that message from the CAN bus (the speed is 500kbps):

can1 00004200 [8] 02 FF FF FF FF FF FF FF
 

Araknid

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Oh how can you seeeee? This be canbus solax x3, message id is sequential, absolutely no encryption there be!


CE0BD09E-A634-405B-A703-715BD9D73EE9.jpeg


Now if you sing that.... or not.
Okay, solax X3 hybrid HV battery is a simple “hello” and “I’m here every 1sec”

with a sequential spam of messages . I can see a counter keep alive message, voltages and current .

I’m datalogging all from cold start to running and will log every message for the next few days... looks like it’s an open format. No deciphering required, may even support dual batteries in parallel by the “wake up” message .

I have two t58 solax triple power batteries (master plus slave)
 
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