I obviously did something wrong, I’ve wired up just the recharge port to the battery and plugged it in, this time the light on the charger went red instead of off. I’ve noticed that if I wiggle the positive wire it seems to stop charging/start charging like it’s a loose connection, but there’s plenty of solder there and it’s solid on the + pad. I’ve also noticed if I put the red lead of the DMM on the + pad of the battery the reading is inconsistent/drops, there’s 2 tiny holes at the base of the + pad, if I stick the probe in there the reading is solid. Should I wore the positive wire into one of the holes or try again on top?
After charging, the battery is now at 3.8V is that it charged? It’s a 3.7V battery apparently.
I’ll try the board again tomorrow and see if I’ve fried it during all this...