📋 Overview
This module lets you charge a multi-cell 18650 lithium-ion battery pack from a simple 5V USB Type-C source — no bench charger or lab power supply required. It takes a low input voltage (3–6V) and boosts it up to the correct charging voltage for your pack: 8.4V for a 2-cell (2S) pack, 12.6V for a 3-cell (3S) pack, or 16.8V for a 4-cell (4S) pack.
Each board you receive is factory-configured for the specific variant you ordered (2S, 3S, or 4S) and for the 2A input current version. You don't need to configure anything — just wire it up correctly and it's ready to go. This guide walks you through the pad connections, what the LEDs mean, and important safety notes, whether you're new to battery packs or you've built a few before.
⚠️ Factory-Configured — Not User Adjustable
This module is factory-configured for a specific 18650 cell count (2S, 3S, or 4S) and its matching charging voltage (8.4V, 12.6V, or 16.8V). This setting is fixed at the factory using solder jumpers and cannot be changed by the user. Be sure to order the variant that matches your battery pack's series cell count — connecting a pack with a different cell count than the module is configured for can result in incorrect charging voltage and damage to your battery pack.
📌 Pin & Pad Layout
The board has labeled pads on both the top and bottom sides:
- Top side: VIN and GND pads next to the USB Type-C connector (input side); GND and BAT pads on the opposite end (battery side)
- Bottom side: IN (with GND/BAT labels) and OUT labels, plus small configuration pads marked 1A / 2A / 4A (input current) and 2S / 4S (cell count) — these are the factory-set solder jumpers that match your ordered variant
OK and CR LEDs are located near the battery-side pads on the top of the board.
🔌 Wiring / Connections
- Connect your battery pack's series-wired cells to the BAT and GND pads on the battery side of the board, matching the polarity shown on the board silkscreen.
- Wire your 18650 cells in series to match the variant you purchased:
- 2S variant: 2 cells wired in series (+ to − between cells)
- 3S variant: 3 cells wired in series
- 4S variant: 4 cells wired in series
- Double-check your pack's total cell count matches the variant printed on your packing slip/order before connecting power — a mismatch will result in incorrect (and potentially unsafe) charging voltage.
- Plug a standard 5V USB Type-C cable from a wall adapter, power bank, or PC port into the VIN connector.
- Once power is applied, the board will begin boosting the input voltage and charging your pack automatically.
🔋 LED Status Indicators
- "CR" LED lit: The module is actively charging the battery pack.
- "OK" LED lit: The pack has reached full charge and the module has switched to constant-voltage (trickle/maintenance) mode.
💡 Tip: It's normal for the "CR" LED to stay lit for an extended period on larger-capacity packs — charging current is intentionally limited to protect your cells, so a full charge from empty can take several hours.
🚫 Limitations & Safety Notes
⚠️ Important: Only connect input power within the DC 3–6V range (5V recommended). Do not exceed 6V input. Always match your battery pack's series cell count to the variant you ordered — connecting a pack with a different cell count than the board is configured for can result in overcharging or undercharging. Never reverse battery polarity, and avoid short-circuiting the BAT or output pads. This module includes overvoltage and low-input protection circuitry, but it is not a substitute for using properly rated, undamaged 18650 cells and correct wiring practices.
📏 Dimensions
Approx. 39 × 18 × 6.3 mm (1.54 x 0.71 x 0.25 inches) L × W × H, weight approx. 5g (0.2 ounces).
🏪 Where to Buy
Buy the Type-C 2S/3S/4S Boost Battery Charger Module at Envistia Mall →
- 📦 Fast US Shipping
- 🔄 Hassle-Free Returns
- 📧 Responsive Customer Support
Disclaimer
This guide is provided by Envistia Mall for educational and technical reference purposes only. Envistia LLC (dba Envistia Mall) is not responsible for any damages, injuries, or losses resulting from the use, misuse, or modification of this product. Working with lithium-ion battery packs carries inherent risks — always observe proper electrical safety practices, use correctly rated components, and never leave charging battery packs unattended. Specifications in this guide are based on manufacturer data and may vary slightly between production batches; always verify critical specifications against your specific unit before use in sensitive applications.