My journal for this Highway!

Day 1: Idea

I bought a broken e-scooter (by broken, I mean completely melted electronics) and decided to rebuild it. I got a new controller and display board, but no way to interface them easily or charging the battery. I then realized: I have tons of 18650 batteries laying around. Why not use them to boost my scooter's voltage, and fix all the problems I'm having on a single board? So this module should feature: - BMS for the extra 12V DIY battery pack - USB Type-C connector to interface with the bluetooth dashboard (both the dashboard and the controller have finnicky JST connectors, I'm replacing them for some solid, modern USBC) - Charger for the batery (The scooter's charger is 42V. Should I charge the extra 12V battery in parallel by stepping-down those 42? I believe a boost converter from 42 to 54.6 will be much more reasonable.) - Overcurrent charge protection (in case the charging port gets shorted) - - Along with as much protections I can think of

Day 2: Schematic Layout

I began the schematic by laying out a few functional blocks and using a BMS design I got from the internet.