Quick and dirty voltage checker for multi-cell batteries (ranges 3.6v-4.2v). This one is 10S, Offfers no reverse current protection.
Based off of the work done here: https://www.youtube.com/watch?v=gCS-p8VnSlg, although there was a bug in his code.
Apllication was for a 10S4P Iion battery setup for an electric skateboard.
OLED is a 0.96 screen similar to: https://www.google.com/search?q=amazon+oled+0.96&rlz=1C1CHBD_enUS877US877&source=univ&tbm=shop&tbo=u&sa=X&ved=2ahUKEwi30Kv0qqbmAhXSZd8KHQ0MBmoQsxh6BAgMECg&biw=971&bih=617&dpr=1.56#spd=11758063574894965900 Arduino Nano clone two MCP3008's sikmilar to: https://www.amazon.com/Adafruit-MCP3008-8-Channel-Interface-Raspberry/dp/B00NAY3RB2/ref=asc_df_B00NAY3RB2/?tag=hyprod-20&linkCode=df0&hvadid=241915774055&hvpos=1o1&hvnetw=g&hvrand=14751501059360930472&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003344&hvtargid=pla-570861476351&psc=1