Jump in battery fully charged

Hi all,

What I don’t understand of the AC200Max when it is being charged. As of 84% it suddenly jumps to 100%.

image

Who can clarify what is happening here? Is my AC200Max unit not functioning right? (I’m using it for 2 months now)

I would suggest fully discharging and fully charging the unit a few times and then review the new data.

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Thank you, that is a good tip to follow.

After that, what is the most battery healthy usage in general. For instance do not deplete the system lower than 20% to extend the batteries life? Please advise.

Yeah, that does certainly look like a BMS calibration issue. Couple full discharge cycles should recalibrate that. For life-cycle, the built-in software retains a safety charge, I believe from what I’ve heard that discharging it to shut-down (0% registered) still retains the charge in the cells themselves necessary for good battery life.

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How did you collect that data?

I use a Raspberry Pi Zero W to connect to the AC200MAX via Bluetooth, fetching the live data, publishing it via MQTT and via Wifi/LAN view it on my computer/iphone with a MQTT client.

Raspberry Pi Zero W:

  • Mosquitto MQTT broker/server (apt-get install mosquitto mosquitto-clients) and configure it to listen on the Wifi ip port.
  • bluetti-mqtt (pip install bluetti_mqtt) see bluetti-mqtt · PyPI

Computer:

  • Install MQTT Explorer and configure it to connect to the Raspberry Pi’s IP address, see http://mqtt-explorer.com/
  • View the published live topics (e.g. dc_input_power) and let it be displayed as graph as in my post.

Bonus:

  • Based on bluetti-mqtt Python script, I hacked together a script to write key data (dc/ac_input_power, total_battery_percent, ac_output_pwer) to a *.csv file. So I can import it into Excel and apply some fancy pancy post-processing. For instance:

If you need more specific examples and help be free to contact me.

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That’s awesome! Thanks for sharing.

@Michael This is pretty amazing man. I definitely will be keeping this is mind for the future. Thanks for sharing!

Informative!Thanks for sharing