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Monitor cells in a battery array?

  • I have a PV system w/ a 16cell battery array. I'd like to monitor the health of the array as well as individual cells. Has anyone seen or done a project like that? I'm trying to get pointed in the right direction. Any advice?

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    @Matt-Stone you need some type of battery management system (BMS) with serial output. Here is an example of it.

    I haven't used this exact device myself the most challenging part would be trying to decode the protocol they encode all the data with.

  • Hi Matt,

    Looking to do something similar, in my case I just want to monitor two voltages in my system:

    • PV voltage (0-150V)
    • Battery bank (40V-80V)

    I ordered an AD7999 A/D converter from control everything. My board has 4 ports, but I think they sell A/D converters with more ports. Don't know if you can use multiple of the same, since the I2C address I think is hardcoded.

    Just getting started with my project


  • that's sounds similar to my project. The battery monitor on my power wall monitors the entire array. I want individual readings on each battery in the array. 8x6v in series = 48v system.... (I also have PV in, so I may hook that up also šŸ˜‰ )

    If you make progress. I hope you report in here. I'll do the same.

  • My first finding: the COntrolEverything AD7999 does not work with the provided Python code šŸ™‚ Reading are not reliable. Will see if I can get the C version cross compiled

  • i haven't made much progress on this. I'm not sure how to really begin. Does anyone have a conceptual wiring diagram that I could start from? If I made a GitHub project would you guys contribute?


  • @Zheng-Han I'm not sure I need a BMS. The system has a smarter inverter/charger for AC and a MPPT solar charge controller. I'm really just looking for a way to monitor DC voltage in at several points in the system (maybe as many as ~20 -- 16 batteries, 3 PV strings).

    In my case, the batteries in my array are sealed lead acid. I found this BMS Voltage Display Energy Transfer Equalizer, Lead Acid 4/ 8 /16 string 36V 48V 60V Lithium Battery Protection Plate

    think we would have any luck connection this to an onion somehow? think it would do what I'm describing?

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