Ultra-Small Lithium Battery Charging Panel 1A Ternary Lithium Battery 3.7V 4.2V Charger Module Type-C With Protection Board

Input Voltage

4.5V – 5.5V DC (5V typical)

Full Charge Voltage

4.2V ±1.5%

Maximum Charge Current

1A (1000mA) default

Over-Discharge Protection

2.5V (cutoff)

Over-Current Protection

3A (typical)

Charging Accuracy

±1.5%

Operating Temperature

-10°C to +85°C

Dimensions (approx.)

27mm × 17mm × 4mm

Connector Type

USB Type-C (input), 2.54mm pitch pads (B+/B- and OUT+/OUT-

Input Options

Type-C port OR IN+/IN- solder pads

Product Overview

The Ultra-Small Lithium Battery Charging Panel is a compact, highly efficient charging solution designed for single-cell 3.7V ternary lithium batteries (Li-ion/LiPo). This Type-C module combines the reliable TP4056 charging chip with DW01 protection circuitry, offering both charging management and essential battery safety features in a tiny form factor.

Based on the industry-standard TP4056 linear charging IC, this module implements a proper Constant Current/Constant Voltage (CC/CV) charging algorithm that is essential for lithium battery safety and longevity . It charges ternary lithium batteries (3.7V nominal) to the correct full charge voltage of 4.2V with ±1.5% accuracy .

What sets this module apart is its integrated DW01A battery protection IC and FS8205A dual MOSFETs, which provide comprehensive protection against overcharge, over-discharge, overcurrent, and short circuits . This “with protection” version is ideal for standalone 18650 cells and other batteries that lack their own built-in protection circuit .

The modern USB Type-C input allows convenient charging via standard USB chargers, power banks, or computer USB ports, while alternative solder pads provide DIY wiring flexibility. The ultra-small PCB size makes it perfect for portable electronics, DIY power banks, Arduino/ESP32 battery-powered projects, and replacing dead charger circuits in consumer devices.

Key Features

  • Integrated Protection Circuit: Includes DW01A battery protection IC and FS8205A dual MOSFETs, providing overcharge protection (4.2V cutoff), over-discharge protection (2.5V cutoff), overcurrent protection (3A), and short-circuit protection

  • USB Type-C Input: Modern reversible connector for easy connection to standard USB chargers, power banks, or computer USB ports

  • 1A Maximum Charge Current: Default charging current of 1000mA (1A), adjustable by changing the programming resistor for lower current applications

  • CC/CV Charging Algorithm: Proper Constant Current / Constant Voltage charging method essential for lithium battery safety and longevity

  • Dual-Color Status Indicator: Red LED indicates charging in progress; Green/Blue LED indicates fully charged or no battery connected

  • Protected Output Terminals: B+ and B- pads connect directly to the battery; OUT+ and OUT- pads pass through the DW01 protection circuit

Technical Specifications

Parameter Operating Value
Input Voltage 4.5V – 5.5V DC (5V typical)
Full Charge Voltage 4.2V ±1.5%
Maximum Charge Current 1A (1000mA) default
Over-Discharge Protection 2.5V (cutoff)
Over-Current Protection 3A (typical)
Charging Accuracy ±1.5%
Operating Temperature -10°C to +85°C
Dimensions (approx.) 27mm × 17mm × 4mm
Connector Type USB Type-C (input), 2.54mm pitch pads (B+/B- and OUT+/OUT-)
Input Options Type-C port OR IN+/IN- solder pads

Pinout & Interface Guide

The TP4056 board is clearly labeled with connection points :

Input Side (Power Source)

Terminal Label Function
USB Type-C Port – Connect to standard 5V USB charger, power bank, or computer USB port
IN+ + / IN+ Alternative 5V power input (positive terminal)
IN- – / IN- Alternative power input ground

Battery Connection (Charging Output)

Terminal Label Function
B+ B+ Connect to positive terminal of the 3.7V Li-ion / LiPo battery
B- B- Connect to negative terminal of the battery

Load Connection (Protected Output)

Terminal Label Function
OUT+ OUT+ Positive output for powering a load (protected against over-discharge)
OUT- OUT- Negative output for load (protected path through DW01 circuit)

Status LEDs

LED Color Meaning
CHRG Red Charging in progress
STDBY Green/Blue Charging complete, or no battery connected

*Note: When no battery is connected, the green LED may be on and the red LED may flash at 1-4Hz intervals .*

Usage Guide

Basic Wiring Instructions

IMPORTANT: This module has NO reverse polarity protection . Connecting the battery backward will damage the chip. Always double-check polarity before connecting.

  1. Connect Power Input: Plug a standard USB Type-C cable into the board’s USB port and connect to a 5V USB charger (capable of at least 1A output). Alternatively, connect a 5V DC supply to the IN+ and IN- pads .

  2. Connect Battery: Solder the positive terminal of your 3.7V Li-ion or LiPo battery to the B+ pad. Connect the negative terminal to the B- pad .

  3. Observe LEDs: When charging begins, the red LED (CHRG) will turn on. When the battery reaches 4.2V and charging completes, the green LED (STDBY) will turn on, and the red LED will turn off .

  4. Connect Load (Optional): For devices requiring protection from battery over-discharge, connect your load to the OUT+ and OUT- terminals. The protection circuit will cut off output if the battery voltage drops below approximately 2.5V .

Setting the Charge Current

The default charge current is 1A (1000mA) set by a 1.2kΩ RPROG resistor . This can be adjusted by replacing the resistor (R3 on the board) :

Desired Current Resistor Value (RPROG)
1000mA (Default) 1.2kΩ
780mA 1.5kΩ
580mA 2kΩ
400mA 3kΩ
250mA 5kΩ
130mA 10kΩ

Current Recommendation: Never charge your battery at a rate greater than 1C (battery capacity). For a 1000mAh battery, a charging current of 400mA is sufficient. If you have small batteries (<1000mAh), replace the R3 resistor with a higher resistance value .

Important Usage Notes

  • Charge Time Calculation: For a fully discharged 2000mAh battery, charging at 1A will take approximately 2 to 2.5 hours.

  • Input Source Requirement: For reliable 1A charging, use a USB power supply rated for at least 1A. A weaker supply will reduce the charge current .

  • Disconnect Load When Charging: It is generally recommended to disconnect the load during charging for optimal battery health .

  • Battery Output 0V? If your battery reads 0V at the OUT terminals, the protection circuit has activated due to over-discharge. The battery is not dead—applying a 5V charge (plugging in USB) will reactivate the circuit .

  • Ampere Meter Caution: An ampere meter can only be connected to the 5V input end of the module .

  • Never Charge Above 1C: Do not charge your battery at a rate greater than 1C (battery capacity) .

Charging Process (CC/CV Algorithm)

The module follows a proper 3-stage charging process :

Stage Condition Charging Mode Description
Trickle Mode Battery < 2.9V 130mA Revives deeply discharged batteries to safe voltage
Constant Current (CC) 2.9V – 4.2V 1A (max) Fast charging at full programmed current
Constant Voltage (CV) 4.2V reached Voltage held, current drops Topping off, completes when current drops to 1/10 of programmed value
Q: What types of batteries can I charge with this module?

This module is designed specifically for single-cell (1S) 3.7V lithium-ion and lithium-polymer (LiPo) batteries (ternary lithium batteries). Common form factors include 18650, 14500, 16340, and pouch cells. It does NOT support 3.2V LiFePO4 batteries, multiple cells in series (2S, 3S, etc.), or NiMH/NiCd batteries.

Q: What is the difference between "with protection" and "without protection" versions?

This “with protection” version includes the DW01A battery protection IC and FS8205A dual MOSFETs. The protection circuit provides overcharge protection (prevents charging beyond 4.2V), over-discharge protection (cuts off load at ~2.5V), and overcurrent protection (~3A). This makes it safe for use with batteries that lack their own built-in protection circuit .

Q: What is the difference between B+/B- terminals and OUT+/OUT- terminals?

The B+ / B- terminals connect directly to the battery. The OUT+ / OUT- terminals pass through the DW01 protection circuit, which disconnects the load if the battery voltage drops too low (over-discharge protection at ~2.5V) or if current exceeds safe limits (~3A). For most applications, connecting your load to OUT+/OUT- is safer .

Q: Can I use this module while it is charging the battery?

Yes, but with caution. You can power your device from the OUT+/OUT- terminals while the battery is charging. However, it is generally recommended to disconnect the load when charging for optimal battery health .

Q: Does this module have reverse polarity protection?

NO. This module does NOT have reverse polarity protection. Connecting the battery backward will damage the TP4056 chip. Always double-check polarity before connecting .

Q: Can I charge multiple batteries in parallel with one module?

Generally not recommended. Connecting batteries in parallel requires them to be perfectly matched in voltage, capacity, and internal resistance. If you must, only connect batteries that are at identical voltage (within 0.1V). It is safer to use a dedicated multi-cell charger.

Q: How do I change the charging current from 1A to a lower value?

The charge current is set by the resistor RPROG (R3) on the module. Replace this resistor with a higher value to reduce current. Refer to the resistor table in the “Usage Guide” section .

Q: Can I use a 12V power supply as input?

No. The maximum input voltage is 5.5V DC. Applying 12V will damage the TP4056 chip. Use a 5V USB charger .

Q: The module gets very hot during charging. Is this normal?

Some warmth is normal due to the linear charging method—excess voltage (5V input – 4.2V battery) is dissipated as heat. The TP4056 has built-in thermal regulation that reduces current if the temperature exceeds safe limits .

Q: Why is my battery not reaching 4.2V or charging very slowly?

Check the following:

  1. Input power: Ensure your USB power supply can deliver at least 1A. A weak supply will reduce the charge current

  2. Battery health: Old or damaged batteries may not reach full voltage

  3. Connections: Poor solder joints can create resistance, reducing effective charge current

Q: What happens when both red and green LEDs are on or flashing?

The red and green LEDs should never be on simultaneously during normal operation. If both are on or the red LED flashes, it may indicate :

  • No battery connected (green on, red flashing 1-4Hz)

  • Battery connection problem (poor solder joint)

  • Battery voltage is too low (below 2.9V, module may be in trickle charge mode)

Q: Why does my battery output 0V?

This typically means the protection circuit has activated due to over-discharge. The battery is not dead—the DW01 protection IC has cut off output to prevent damage. Applying a 5V charge (plugging in USB) will reactivate the protection circuit .

Q: What can I build with this TP4056 charging module?

Popular applications include :

  • 18650 battery chargers for DIY power banks

  • Arduino/ESP32 portable power supplies with battery backup

  • DIY Bluetooth speakers with rechargeable batteries

  • Smart home sensors running on battery power

  • Rechargeable LED flashlights and lanterns

  • Portable medical devices requiring battery power

Q: Is this module suitable for beginners?

Yes. The TP4056 module is widely recommended for beginners due to its simple connections, clear labeling, and built-in protection features. The onboard LEDs make it easy to see charging status at a glance .