Core Ink battery status

  • I can't find a way to get the state of the battery using UIFlow. Any hint?

  • Hello @luarmr

    the best there is for M5CoreInk is the battery voltage under Hardware - Battery - Get battery voltage.


  • @felmue thanks for answering, how I can use this information to know how much battery left is in the device? Sorry if this is a very basic question, I am learning.

  • Hello @luarmr

    well, you can't really, at least not very accurately. The battery voltage can go up and down quite a bit depending on what M5CoreInk is doing (e.g. idle, update screen, etc.). The best you could try is starting from a full battery, then periodically read and record the voltage over normal usage until it dies and then use that for future discharge cycles.

    To more accurately measure the capacity that is left in a battery you'll need more information, e.g. current going into (during charging) and out of (when used) the battery. Unfortunately the architecture in M5CoreInk doesn't allow to gather any information (charging, not charging, charge state, etc.) but the battery voltage.


  • @felmue Thanks let's see if I can figurate something.
    The only thing that I want is to know that the battery is low. I don't really need an exact number.

  • @luarmr From what I noticed is that a voltage above 5V it's charging. Right now I'm trying to figure out the state that its battery is running low and I need to charge it soon.

  • @leopoldking Hi there, I try to implement such a notice as well. As mentioned here by other, I as well dont care about accuracy, more about a warning when the unit needs to be recharged.

    My Full Battery starts at around 4242. so on what number the unit wont be able to turn on?

    I display 4 states "100, 75, 50, 25 and LOW BAT" based on values of the "get battery voltage" but I couldnĀ“t find out yet below what voltage the unit is "dead".

    • Maybe someone has data on battery usage with the core ink?
    • What is the minimum battery voltage the core ink needs to operate?

    thanx for any hints

    I implemented a cycle every 4 hrs to "wake up" - "connect to ssid" - "get battery voltage" - "get ntp time and date" - "write ntp to json" - "read json" - "display infos on several labels" - "refresh display (two times and 2 times partial)" - "power off after 3 minutes". Each cycle consumes around 35-40 of that full 4242.

    #coreink #battery #batterystatus #voltage

  • @ebksuper By digging the web I found a python script what translates to this in UIFLOW / BLOCKLY.
    I translated this the best I could to UI FLOW.

    The mAh are of the specs of CORE INK and my full loaded battery gave out on "get battery voltage" 4242 asuming this translates to 4.2V.
    So far it spits out reasonable numbers. I am testing if this is accurate enough to be an indicator when to recharge.

    Please comment if you found errors or have a more elegant solution to get a Batters Status.
    Thanx : )

    UIFLOW image for Batter status

    #uiflow #battery #coreink #m5stack #core