Spark Logic

18650 lithium-ion cell connection guide

18650 lithium-ion cell Bare cylindrical cell wiring guide with power, signal assignments, and bench checks.

Bare cylindrical cell

2 contacts Current package
Protected pack connector 2 contacts

Molicel and Honcell · Molicel INR-18650-P28A · 18.6 mm maximum diameter × 65.2 mm maximum height.

Identify the bare cell terminals

Required

Use the label and mechanical drawing to identify the positive cap and negative bottom. Leave loose cells disconnected and follow the CPSC handling guidance.

Bench checks

  • Verify the model from the manufacturer label and locate the positive-end insulator in the drawing.
  • If you need a load connection, open the Protected pack connector guide for a factory-assembled pack and its matching harness.

Molicel P28A datasheet, p. 1; CPSC safety release 21-065, January 2021.

Bare cylindrical cell wiring map

Select a contact to inspect it.

Bare cylindrical cell
Side view with the insulated positive cap to the left. The map uses 1 and 2 as terminal identifiers.
Selected pin details

2 · −

Negative terminal · Ground

The flat bottom is negative. Keep the steel can and positive cap insulated from one another.

Molicel P28A datasheet, p. 1

Electrical limits · Pin in the reference

Models and documents

This reference covers the bare Molicel INR-18650-P28A and the separately documented Honcell HCC18650FC protected assembly. Check the exact manufacturer code for chemistry, voltage, capacity, load rating, protection and fit.

INR-18650-P28A
Industrial bare cell described in the Molicel product datasheet.