Wanted: Custom BMS with PWM development

Hardware diyBMS
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Hi, new member. I hope it’s okay to do this, if not, please let me know and I’ll delete it. I’m not here to ruffle any feathers.

As a bit of background, I own a small battery company in Australia.
We design and sell LiFePO4 batteries and are somewhat innovative as well. For example one I got JBD to develop a 250A smart BMS with an output (through an optocoupler) to turn on and off a 5A active balancer whenever the onboard passive balancer turns on.

But I’ve also got a more ambitious BMS design in mind and was hoping that perhaps one of you might be able to help.
So, I’m also looking at building a hybrid starter battery that uses LiFePO4 and supercapacitors (happy to go into detail later).
For this, I want a 100A 4s BMS. There are hundreds to choose from, but what I want doesn’t seem to exist yet, as I also want it to have an integrated PWM that utilises the MOSFETs to modulate the current to 100A max (ideally the maximum current would be able to be set, either via Bluetooth or even through flashing firmware).

This is outside the scope of my skills, so I’m looking to see if there’s anyone that might want to develop something like this and I’ll pay an agreed amount.

To give back to the community, I’d also be happy to make both firmware and hardware open source.

If anyone is potentially interested, please let me know and we can either discuss on here or set up a Zoom call.

Again, hope this doesn’t go against any rules!

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Welcome, Ruben, to the OEM forum.

@glyn.hudson & @TrystanLea are the owners of OEM (and Megni, the company that designs and manufactures the “Emon” range, but not the BMS) and they are the final arbiters of the rules. I think you’ve already recognised one hard and fast rule - if you receive the community’s help, the result must be published under the same open-source license as everything here is.

I don’t know whether you’ll get any takers, however. Most people here contribute in their spare time, which is often in short supply.

1 Like
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Thanks for your reply!
I’m still going back and forth what to do about this BMS. I honestly think that an ESP8266 (or better yet ESP32) based BMS solution would be great for a commercial BMS! Having worked with Daly and JBD, I know both their firmware can be buggy at times and having open source firmware is a great way of getting a resiliant result. But I’m preaching to the converted!

I’m definitely cognisant that people are contributing in their spare time, I’m hoping that a payment might help with that. I don’t know what quantum that payment would be, but I think we could work something out.
And just to make it absolutely clear, yes I would be happy to make anything that come of it open source (firmware and hardware).