Solar Power Manager 5V for Li Batteries (MPPT, Single-Cell Li-ion Charging, 5V/1A Output)

This Solar Power Manager 5V combines solar charging, lithium-battery management, and a regulated 5V supply for compact IoT and renewable-energy projects. Designed for a nominal 5V solar panel and a single-cell 3.7V Li-ion or Li-polymer battery, this module supports up to 900mA charging from solar or USB input. Fixed 5V constant-voltage MPPT helps a compatible panel operate near the intended power point, while the 5V/1A output supplies low-power controllers and peripherals. The 33.0mm*63.0mm board suits solar environment monitors, small robots, and portable power projects. A solar panel and battery are required separately.

Fixed 5V MPPT for Compatible Solar Panels

The constant-voltage MPPT function targets a fixed 5V operating point, matching solar panels with a suitable nominal maximum-power voltage. This approach helps manage solar charging as available sunlight changes, giving a compact project a dedicated solar input rather than relying on USB charging alone. Select a compatible panel within the stated SOLAR IN requirements; this fixed-voltage design is intended for 5V panels and does not automatically adapt to 12V or 18V panels.

Solar and USB Charging for a Single Lithium Cell

Up to 900mA charging supports a single-cell 3.7V lithium battery through trickle, constant-current, and constant-voltage charging phases. Solar input enables outdoor energy collection, while USB charging provides a convenient option during development or when solar energy is unavailable. The 4.2V±1% charging cutoff matches the specified battery type. This dual-input arrangement makes bench testing and outdoor deployment more practical without changing the project's battery-management module, provided the battery supports the charging current.

Regulated 5V Power with Selective Output Control

The regulated output provides up to 1A at 5V, shared across the pin-header and USB connections, for a controller and compatible peripherals. The pin-header output supports ON/OFF control, allowing a project to switch connected loads when required. USB OUT remains enabled, making the USB connection useful for a low-power controller that needs to stay supplied while other loads are switched. Available operating time depends on the complete system's energy budget and battery capacity.

Protection Functions for Embedded Solar Projects

Battery, solar-input, and output protection functions support a more robust embedded power setup. The V1.1 revision adds battery overcurrent and overdischarge protection, allowing use with the specified lithium cells whether or not an additional protection circuit is included in the battery pack. Output short-circuit, overcurrent, and overheat protection complement reverse-connection protection on the solar input. The included cooling fin and thermal pad support heat management when charging at higher current.

Check the brief specification for all Solar Power Manager Series Products.
 
Version History
V1.0: It is highly recommended to use a 3.7V lipo battery with protection circuits to improve battery safety.
V1.1(Newest): Battery (BAT IN) overcurrent and overdischarge protection is added to improve battery safety. It can be use for 3.7 lipo battery no matter it is packed with protection circuits or not.

Board Overview

Connection Diagram

For a 5V solar panel and a single-cell 3.7V lithium battery. The panel and battery are not included. The 5V/1A output rating is a load limit, not a promise of continuous solar power: available runtime depends on panel output, sunlight, battery capacity and your device's duty cycle. This is not a controller for a 12V battery pack.