Deye 8kW Inverter - BMS options for DIY battery bank?

[ssean]

Greetings,

Is anyone here using a Deye inverter with a DIY LiFePO4 battery bank?

My battery bank consists of 32x 280Ah EVE prismatic cells. I have 16 cells wired in series, which give me 2x 280Ah 48V banks.

I'm having a hard time finding a BMS that is compatible with the Deye Inverter.

I've read that Batrium and Orion **might** work, but I was hoping for something solid before purchasing.

Thanks!

[JustinSchoeman]

I believe

https://lithiumbatteriessa.co.za

have a Daly Smart BMS with customised firmware that can communicate with Deye/Sunsynk. Not sure if they can parallel though.  Maybe contact them and find out?

[ssean]

Thank you

[Eric21]

@ssean - did you find out if the Daly Smart BMS could support the Deye inverter or find any info on custom firmware for it?

The Deye inverter supports Pylontech, Freedomwon, an Dyness among others, but I have only found the Pylontech CAN protocol document and the messages are different from Deye.

If anyone has the Freedomwon CAN protocol I would like to take a look.

Daly CAN protocol is available from here:  https://diysolarforum.com/resources/daly-smart-bms-manual-and-documentation.48/

Cheers,

Eric

[PowerUser]

1 hour ago, 87 Dream said:

A massive limitation of the Daly BMS, is that it cannot be paralleled. The best DIY BMS is the QUCC that Andy is using for his Off grid garage, in Aus. There limitations of the Smart Daly is that the MOSFET architecture cannot handle parallel setup. You will have zero protection with this device in Parallel. The MOSFETs are unable to close or open based on their protection. So when the BMS detects a problem, it's a runaway train. There is a lot of heat build up. 

The QUCC makes use of a physical contactor. So it works & is designed for this exact type of operation. No heat build up.

87

His problem with QUCC BMS was the balancing current was too low to be useful. Apparently, JK and Heltec BMS come with 2A active balancer build-in. Andy has another video lined up for the weekend to test the JK BMS. 

Edited September 25, 2021 by PowerUser

[PowerUser]

There is something else to consider as well, you might find a great BMS for your setup and order from China. Wait 3 or more months to arrive and get everything working. But if the BMS fails down the line after few months or a year - then what? Your whole system will be down for several months, while waiting for another shipment from China. Not having good options available locally is really a big issue. 

[phidz]

15 hours ago, 87 Dream said:

That is why the plan is to make these locally available in the local market & in stock. I myself have started off as a consumer & understand the frustrations you talk about above. The plan is to get basically all of the kit that Andy has in his tool box which would be the minimum dispatch equipment to do a full DIY build safely & to monitor the cells properly & keep them in a good state going forward.

Minimum equipment: Variable power supply charger 0V-60V, 5-10A. QUCC BMSs only because they are Parallelable & therefore expandable. Nothing against the Smart Daly but I'd rather offer something that can be grown from the offset. LiFePO4 Cells 120ah, 280ah & 310ah. The rest of the miscellaneous tools also, likes lugs, crimpers, wiring both small & large gauge. Active Balancers, the smart & not so smart versions. 

I must admit the complete joy of putting together a DIY LiFePO4 bank of cells & to see it in action can be one of the most satisfying projects that one can put together. As you stated above all that is required is quality trusted sources of equipment on our local markets.

Andy's channel is a direct builders guide for the absolute novice & for the expert builder. But really this type of project is not beyond any person whom respects the handling safety guidelines & is patient to learn. 

87

 

Link to Andy's channel please