USB Type-C 15W 2S/3S Lithium Battery Charging Boost Module

USB Type-C Charging for DIY Lithium Battery Packs

This 15W lithium battery charging boost module provides a compact charging solution for DIY electronics and battery-powered projects. It supports 2S lithium-ion battery packs by default, with board-level configuration for 3S operation. Power can be supplied through the USB Type-C port or soldered input connections.

For a two-cell series pack, the built-in equalization function helps balance the cells during charging. LED indicators make it easier to check charging progress and identify an abnormal condition.

Important: This is a charging module, not a replacement for a battery protection board or BMS. The battery pack must have a suitable separate protection board.

Key Features

• 15W synchronous switching boost charging: designed for compact lithium battery charging projects.
• 2S default configuration: supports two 3.7V nominal lithium-ion cells connected in series.
• Configurable 3S operation: requires solder-jumper and resistor modifications before use.
• 2S cell balancing: uses the BM connection at the midpoint between the two cells. Balancing is limited, so use closely matched cells.
• USB Type-C or soldered input: offers connection options for prototyping and integration.
• QC input support: with a compatible QC power supply, the Type-C input can adjust its input voltage to improve charging efficiency.
• Adjustable charging current: set through onboard resistor configuration, not a user-operated dial.
• Compact board: approximately 32 × 18 × 5 mm.

Technical Specifications

• Battery chemistry: 3.7V nominal lithium-ion cells with a standard 4.2V per-cell charge cutoff.
• Series configuration: 2S by default; 3S after hardware modification.
• Pack charging voltage: 8.4V for 2S; 12.6V for correctly configured 3S operation.
• Charging power rating: 15W.
• Listed charging efficiency: 94%; actual performance depends on operating conditions.
• Input connections: USB Type-C port or solder pads.
• Cell equalization: available in 2S configuration.
• Approximate dimensions: 3.2 × 1.8 × 0.5 cm.

LED Status Indicators

• Red LED: normally illuminated during operation.
• Blue LED on: charging.
• Blue LED off: charging complete.
• Blue LED flashing: abnormal condition detected.

Setup and Compatibility Notes

Check the board configuration, cell chemistry, polarity and required pack voltage before connecting a battery. For soldered power input, the supply voltage must be lower than the battery pack voltage because this connection operates in boost mode.

For 2S balancing, connect BM to the junction between the two series-connected cells. Do not assume the balancing function applies to 3S operation.

The original module information describes current-setting resistors of 100kΩ (approximately 0.9A) and 180kΩ (approximately 0.5A), with current calculated as 90000 ÷ resistance in ohms. Verify the fitted components and board documentation before changing them. Available charging current depends on the input supply, battery voltage and module power limit.

Changing to 3S operation requires bridging the appropriate configuration contact and removing the specified resistor. Charge-cutoff voltage, timeout and optional NTC temperature sensing also require resistor-level configuration. These changes should be performed only with the correct board-specific wiring diagram and component references; do not modify unidentified pads or resistors.

Battery safety: Use matched cells and a suitable protection board. Check all connections before powering the module, and do not leave a charging battery unattended.