Hart 20v Battery Pinout Diagram |top| May 2026

The Hart 20V battery uses a 5-pin interface typical of modern lithium-ion power tool systems. While the pins are not always explicitly labeled on the casing, testing and teardowns identify them as follows: Hart 20V Battery Pinout Diagram Voltage Reading (to Negative) 1 + (Positive) Main power output ~20V (Fully Charged) 2 TH Thermistor (Temperature Monitor) ~20V (Connected to Positive) 3 ID Tool Identification/Data 4 C Control/Communication 5 - (Negative) Main ground/return 0V (Reference)

Common Uses

Overall, I'm thoroughly impressed with this Hart 20V Battery Pinout Diagram, and I highly recommend it to anyone who uses Hart 20V batteries. It's a valuable resource that's saved me time and hassle, and I'm confident it will do the same for you. Hart 20v Battery Pinout Diagram

  1. Never short B+ to B- – even briefly. The current can exceed 100A instantly, melting wires and causing fire.
  2. Never charge a Hart battery using only B+ and B- without the communication line. The charger relies on the data pin to regulate voltage and stop at 21V.
  3. Do not disassemble a swollen or physically damaged battery.
  4. Always use a proper Hart charger – it’s designed to interpret the data pinout safely.
  5. If building an adapter, include a low-voltage cutoff circuit (set to 15V) to protect against over-discharge when using B+ and B- directly.

TH (Thermistor): Used for temperature monitoring to prevent overheating during use or charging. The Hart 20V battery uses a 5-pin interface

After searching through various sources, I found a few pinout diagrams for Hart 20V battery packs. Keep in mind that these diagrams might not be universally applicable, as configurations may vary depending on the specific battery model or tool. Wiring replacement connectors Building a DIY adapter or

Battery Resets: If your battery refuses to charge despite correct voltages, placing it on a Hart 20V 4-Port Charger for a few minutes can sometimes trigger a manual reset.