What it does and why you need it Provides uninterrupted power to small electronics by combining a lithium battery boost charging module with a builtin UPS circuit. If mains power is interrupted, the module instantly switches to battery power so connected devices keep running without reboot or data loss. Simplifies battery charging and backup power in one compact board so you can avoid separate chargers, manual switching, or complicated wiring. Key benefits Seamless UPS switching: automatic transition between external power and battery ensures continuous operation for sensitive electronics and controllers. Flexible charging options: charge lithium batteries via either the Micro USB port or a DC 5V input, fitting a range of common power sources. Dual battery sockets: supports charging of two lithium batteries, giving you simpler battery management and longer available runtime when both cells are used. Clear charge status: a dualcolor LED indicates charging state; green shows a full charge and that charging has stopped automatically to protect the battery. Important attributes Function: lithium battery boost charging module with integrated UPS for direct device load from power supply or batteries. Compatibility: designed for lithium battery charging and for supplying devices directly from either mainsderived 5V inputs or battery power. Performance: automatic switching and automatic stop at full charge for reliable, lowmaintenance operation. Connectivity: two battery sockets, Micro USB charging port, and DC 5V input to suit common power sources and cable types. Typical use scenarios Backup power for small electronics and microcontroller projects where continuous operation is critical (avoid sudden resets during power loss). Field or portable applications that need onboard battery charging plus the ability to run directly from an external 5V source. Test equipment, sensors, or lighting modules that benefit from a simple UPS and visible charge indication to prevent overcharging. Practical considerations The module supplies power directly from either the external 5V input or the installed lithium batteries, and the LED indicator helps you know when batteries are fully charged and charging has stopped. Use with appropriate lithium cells and wiring practices; follow battery safety and charging guidelines for your cells and application.