Dual-slot lithium battery capacity tester / battery discharge analyzer module, commonly sold as a 18650 battery capacity tester board. It is used to test the actual capacity, voltage, discharge performance, and internal characteristics of rechargeable lithium-ion cells.

Product Description

Dual-Slot 18650 Lithium Battery Capacity Tester Module with TFT Display

This electronic testing module is designed to measure the real capacity and discharge performance of lithium-ion batteries. It supports cylindrical rechargeable cells such as 18650, 26650, 21700, and similar 3.7V lithium batteries that fit within the battery holders,Lithium Battery Capacity Tester

Key Features

• Dual battery slots for testing one or two cells.
• TFT digital display for clear real-time readings.
• Displays:
  • Battery voltage (V)
  • Discharge current (A)
  • Capacity (mAh)
  • Energy (Wh)
  • Test time
  • Temperature status (depending on firmware version)
• Built-in power resistor load (white ceramic resistor) for controlled battery discharge.
• Multiple push buttons for setting test parameters and navigating menus.
• USB-C connector for module power supply.
• Automatic battery discharge and capacity calculation.
• Compact PCB design suitable for hobbyists, technicians, and battery recyclers.

Typical Specifications

Applications

• Testing new or used lithium-ion batteries.
• Sorting batteries by capacity.
• Battery pack matching.
• Quality control and maintenance.
• DIY power bank and battery projects.
• Recycling and refurbishing battery cells.

Visible Components in the Image

1. Two battery holders (for cylindrical lithium cells).
2. Large ceramic resistor used as the discharge load.
3. TFT display showing voltage, current, capacity, and energy data.
4. Control buttons for setting and starting tests.
5. USB Type-C port for powering the tester.
6. Microcontroller circuitry for measurement and calculations.

How It Works

1. Insert a charged lithium-ion battery into the holder.
2. Connect power through the USB-C port.
3. Set the discharge parameters using the buttons.
4. Start the test.
5. The module discharges the battery through the load resistor.
6. Capacity (mAh) and energy (Wh) are calculated automatically and displayed when the