New to this world, and at the risk of being flamed myself, but here goes. I have had two18650 batteries die when nrf52840 & L67K power being supplied through usb-c connector, but with a battery connected. The battery connection being made via exqqqquisite soldering to the PCB pads.
The bundle is running meshtastic for a sensor project. Each battery exhibits 0V after a period of hours in this mode.
I had envisaged the nrf52840 and L67K would have a surplus of power for combined needs from the USB connected power source and trickle charge the 18650 at the same time. Not sure if it’s over or undercharrrring in this case but it’s doing a grand job. The first time I put it down to old battery, the second time I woke up. I assume it’s overdischarging due to low level of charging through onboard power circuit. Even a blind squirrel finds an occasional acorn.
Is there a reference standard approach for protecting the battery in this case? Is a TP4056 sufficient between the battery pad connectors and the battery, or are there other approaches to consider.
Thank you.
PJ 