[chbot] Lithium Ion charge/protection circuit

[Andy ZL3AG]

There's a couple of versions of these boards floating around on ALiExpress with slightly different component layouts. Also be aware that there is a plain TP4056 charger board WITHOUT the batttery protection chips out there too, so don't order that one by mistake.

I'm pretty sure the schematic shown at http://radiostud.io/build-power-supply-portable-iot-device/ matches the aliexpress boards.

Cheers,

Andy