This versatile LiIon/LiPo battery charger accepts power from three sources: a 6 V solar panel (via 2.1 mm DC jack), USB Mini-B, or a 5 V DC adapter. It features automatic charging current tracking that draws the maximum possible current from a solar panel in any light condition, providing near-MPPT (Maximum Power Point Tracking) performance without the cost of a buck converter.

The charger includes smart load sharing, which automatically uses input power when available to prevent the battery from constantly cycling between charging and discharging. A dedicated LOAD output port lets you power your project while simultaneously charging the battery.

Key Features

• Triple Input – Charge via 6 V solar panel, USB Mini-B, or 5 V DC adapter
• Automatic Current Tracking – Draws maximum current from solar panels in any light condition
• Smart Load Sharing – Powers your project from input when available, preserving battery life
• Adjustable Charge Rate – Set for 500 mA by default, adjustable from 50 mA to 1 A via resistor
• Three Status LEDs – Power good, charging, and done indicators
• Low Battery Indicator – LED output triggers at 3.1 V
• Temperature Monitoring – Solder in a 10 kΩ NTC thermistor (not included) for battery temperature protection
• JST Connectors – 2-pin JST for both BATT and LOAD ports

Specifications

• Battery Chemistry – 3.7 V / 4.2 V Lithium Ion or Lithium Polymer
• Input Sources – 5–6 V DC, USB Mini-B, or 6 V solar panel
• Default Charge Rate – 500 mA (adjustable 50 mA – 1 A)
• Low Battery Threshold – 3.1 V
• DC Jack – 2.1 mm barrel jack

Package Contents

• 1× Assembled charger board
• 1× 2-pin JST cable
• 1× Stabilisation capacitor (must be installed in your finished project)

Ideal For

• Solar-powered outdoor projects
• Portable battery charging stations
• IoT devices with solar harvesting
• Off-grid electronics prototyping

Resources

• Charger Tutorial & Design Guide