On board battery protection circuit with protection against overcharge, overdischarge, overcurrent, short circuit, and reverse connection; supports balanced charging for stable operation. Includes a complete supporting information manual to assist setup and use. On board warning alerts the user if the battery is connected reversely, helping prevent damage. I2C interface enables real time measurement of battery current, power and remaining capacity, providing live monitoring of the module's operation. Use scenarios: Integrate into battery packs for portable electronics or DIY projects that require safe charging and continuous status monitoring. Implement in embedded systems or robots where real time current, power and remaining capacity data is needed via I2C. Deploy in small tools or hobby devices to ensure protection and quick detection of reversed connections, reducing risk of damage.