Project idea
Design a 3S Li‑ion battery management system using an STM32 controller that continuously measures pack voltage, current, and temperature, and actuates cutoff via relays/MOSFETs when limits are exceeded to stay within the safe operating area. The build targets EV safety learning by addressing common fire triggers through monitoring, proper charge termination, and thermal protection at the pack level.
Project description
An STM32 microcontroller interfaces with voltage and current sensors and a temperature probe, displays live parameters on a 16x2 LCD, and controls charger and load paths to prevent over/under‑voltage, over‑current, and over‑temperature events in a 3S pack. Charging is supervised so that when full‑charge conditions are detected the system isolates the charger and indicates “battery fully charged,” while in discharge it tracks current draw and cuts off on anomalies to mitigate thermal runaway risk. The approach mirrors BMS functions used in EVs—measurement, computation of limits, and protective switching—adapted to a lab‑scale prototype.
Total list of components (names only)
STM32 controller board
Temperature sensor
Voltage sensor
Current sensor (INA219 module)
16x2 LCD display
3S Li‑ion battery pack
Protection/charging circuitry (relays/MOSFETs/BMS)
Push buttons/switches
3S Li-ion Balance Charger Module
LEDs
PCB board
Resistors
Capacitors
Transistors/MOSFETs
Cables and connectors
Buzzer
Enclosure/joystick‑style frame
Screws and bolts
Features
Battery status monitoring with live voltage, current, and temperature on LCD for visibility and diagnostics.
Safe charging control with automatic termination and protective cutoff to prevent over‑charge, over‑current, and over‑temperature.
Thermal monitoring with audible/visual alert and charger/load isolation to reduce thermal runaway risk during charge and discharge.
Applications
Educational EV battery safety demonstrator for e‑bike/e‑scooter pack supervision concepts.
Lab prototype for teaching BMS monitoring, cutoff control, and fault handling in embedded systems.
Pre‑integration testbed for pack‑level safety strategies in small mobility or robotics platforms.
Project Includes:
Fully assembled and tested circuit
Circuit diagram
Source code
(For DIY KITs - only the components will be provided)
Project Types:
- DIY KIT(Do IT YourSelf KIT) - We are providing only components in this kit for this project
- DIY KIT with Code & Circuit Connections - Along with the components, you will get the Code and the Circuit Connections file to help you build the project easily.
- Readymade Breadboard - We are providing fully assembled, tested and ready-made project using plug-n-play jumper wires and breadboard with all the other components, code & circuit diagram.
- Readymade Soldered - We are providing fully assembled, tested and ready-made project soldered on a PCB with all the other components, code & circuit diagram.
Shipping dimensions (cm)
Use a protective carton around 22 × 16 × 10 cm to allow foam/bubble wrap clearance around the enclosure, LCD face, and battery pack. Retail LCD packaging practices emphasize small boxes with cushioning, which guides box sizing for safe last‑mile shipping of electronics assemblies.
Estimate project weight
Approximately 400 g total for a plastic‑enclosure build with one 3S 2200 mAh pack and standard modules and wiring
Notes: All the products are made by LearnElectronics India and not for re-sale. If you want to order a product, please reach out to us at +91-7600948607.
