UPDATE - It's important for this project to use a better 2S BMS board with overcharge recovery voltage feature (link below).

A big Thank You to my patreons, especially my favorite - Kyle Shankin :)

My Patreon campaign:   / sorindiy  
My Facebook page:   / sorindiy  
My Instagram:   / sorin.diy  

If you are a nice lad and want to donate to me on Paypal, here you go: [email protected]

Schematic: https://i.imgur.com/PgwSa2K.jpg

Components list:
2S BMS with balance: https://s.click.aliexpress.com/e/_DeM...
plastic box 90x70x28mm: https://s.click.aliexpress.com/e/_AbIKYx
XL6009 boost converter: https://s.click.aliexpress.com/e/_DkU...
DC-005 5.5x2.1mm female connector: https://s.click.aliexpress.com/e/_A9UT4g
Small switch 10x15mm: https://s.click.aliexpress.com/e/_DnN...
5.5x2.1mm jack (male, 22AWG): https://s.click.aliexpress.com/e/_Dmq...
Small voltmeter: https://s.click.aliexpress.com/e/_DmD...
8.4V 2A charger: https://s.click.aliexpress.com/e/_DEG...

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