Portable 120mm 18650 Desk Fan

Portable 120mm 18650 Desk Fan

A compact and powerful portable desk fan built around a standard 120mm PC fan, powered by a single 18650 battery with integrated charging and step-up electronics. Designed for long runtime, quiet airflow, and adjustable positioning, this fan is ideal for desks, workshops, bedside tables, or portable cooling setups.

Features

• Designed for standard 120mm PC fans
• Powered by a single 18650 Li-Ion battery
• Integrated load/charge controller and step-up converter
• Runtime of more than 8 hours depending on fan and battery capacity
• Adjustable tilt mechanism for directing airflow
• Compact enclosure with clean cable management
• Ventilated electronics compartment for airflow and cooling
• Uses 4x M3 screws and 4x M3 heat-set inserts for assembly
• Portable and lightweight design
• Easy-to-print parts with a practical assembly layout

Assembly & Usage

The housing is designed to fit a 120mm fan together with a 18650 cell holder, charging module, and step-up converter. All electronics are mounted inside the enclosure, keeping the build compact and portable.

For assembly, install 4x M3 heat-set inserts into the mounting points and secure the parts using 4x M3 screws. After wiring the electronics, close the enclosure and mount the fan.

The adjustable side mounts allow the airflow direction to be changed easily for different desk or workspace setups. The fan can be recharged through the integrated charging circuit and is intended for portable everyday use.

Background / Motivation

This project was created as a practical portable cooling solution using commonly available PC fan components and 18650 batteries. Many small USB fans either lack airflow or have poor battery life, so this design focuses on combining efficient cooling performance with long runtime and a clean, functional enclosure.