Lipo Rider V1.3 - measuring battery level

[arthurlutz]

Am powering (and charing) my wipy with the Lipo Rider V1.3 from seedstudio http://wiki.seeed.cc/Lipo_Rider_V1.3/ and a Li-Po battery.

Reading the excellent write up by Dominik Kapusta about using wipy to measure air quality https://kapusta.cc/2017/12/02/home-made-air-quality-monitoring-using-wipy/ I really liked the "push the battery level to a metrics system" and would like to reproduce it. His measurements of the battery level use the following code https://github.com/ayoy/upython-aq-monitor/blob/master/lib/adc.py but I am not using the development board (which probably has some wiring for this to work). How could I wire my board to the lipo rider (if needed at all) to reproduce the same thing ?

[seb]

The pinout sheet (https://docs.pycom.io/chapter/datasheets/downloads/expansion-pinout.pdf) for the expansion board details what connections are made between the battery and the Pycom module to allow battery measurement. You would need to access the battery before it is regulated by the "lipo rider" board.

[arthurlutz]

@seb thanks for you answer, I'm a bit afraid of "frying" my pycom device by doing such a connection, can I check voltage levels with a voltmeter first ? What values should be OK?

If I read https://docs.pycom.io/datasheets/boards/expansion2/ correctly, I should connect G3/P16 ? Do I have have to connect ground or they already share it since it's powering the device ?

[andrethemac]

@arthurlutz I'm using a Max17043 to read the State of Charge of a LiPo Battery, It sits between the battery and the charger or the wipy. (https://datasheets.maximintegrated.com/en/ds/MAX17043-MAX17044.pdf)
sparkfun has a nice board for it (https://www.sparkfun.com/products/10617)
It uses I2C to get the state. Even wrote a library for it (https://github.com/andrethemac/max17043.py).
André