Battery Monitor
Sensors · Board: ESP8266 · Day 77 of 100
Watch a 18650 cell's voltage through a divider on the ESP8266, reported to Blynk. Never guess battery level again.
How it works
A resistor divider scales the 18650 cell's voltage down into the ESP8266's ADC range, and periodic readings go up to Blynk as a battery gauge. Voltage maps to charge level through the cell's discharge curve, so the dashboard shows a meaningful percentage instead of raw volts.
What you'll learn
- Voltage divider design
- Battery discharge curves
- Remote battery telemetry
- ADC range scaling
Full project: code, wiring diagram & Wokwi simulation
The complete build guide lives in the original repo. Ours is a summary — the real thing is one click away.
Open full project on GitHub ↗Summary by SkillShop. Project by Kritish Mohapatra — code and diagrams belong to the original repo.
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