Earlier this year, I purchased a Wismesh Tag from the RAK Official Store on AliExpress.
The day before yesterday in the evening, according to the Meshcore app, the battery level was around 25%.
By morning, it was no longer working.
It did not respond to button presses.
When connected to a charger, a faint red LED lights up and a weak whistling sound can be heard. It still does not respond to buttons.
After being plugged in for a couple of hours, the node booted up for a short time. I managed to see in the app that the battery voltage was 2.55V with 0% charge, and then the node turned off again.
I left the node on the charger for the evening and through the night; in the morning, the situation was identical: it does not work and does not respond to buttons.
I have a few questions:
How can I repair it myself and restore its functionality?
Is the only solution to replace the battery with an equivalent one (spec: SH503450)?
What is the issue causing the node’s circuitry to allow the battery to discharge to such a low level that it loses functionality? How can I prevent this from happening again?