The Ultimate Power Bank for Digital Nomads and Hackers
The Omnibus 4x8 is a DIY, backpack-sized power station packing 345Wh of juice to charge everything from your phone to high-power drones.
“I just don’t need any more power for my portable devices,” said no one ever. Keeping our laptops, tablets, phones, travel routers, and everything else powered up on the go is tough to do. Typical battery banks might charge your phone a couple times, but they aren’t going to do your laptop any good. So, what are we to do until a real Mr. Fusion arrives? We can only lug just so much stuff around with us, after all.
Engineer Luq1308 has come up with a potential solution to these problems. He has created a DIY power bank that can keep all your equipment charged up, yet it can still easily be carried in a backpack. Called the Omnibus 4x8, this power bank delivers a feature set that rivals commercial solutions.
At the core of the device is a 345-watt-hour lithium-ion battery pack, roughly equivalent to several large laptop batteries. The pack uses 32 new 18650 cells arranged in a 4-series, 8-parallel (4S8P) configuration, yielding about 96,000 mAh at 3.6 volts. A 4S 30-amp battery management system monitors cell voltage, prevents over-charge and over-discharge, and provides basic safety protections.
Instead of a simple USB output, the Omnibus 4x8 functions more like a miniature power station. It offers four 36-watt USB-C ports, a 100-watt bidirectional USB-C port, a 120-watt bidirectional DC jack, and a 150-watt AC outlet via an onboard inverter. An XT60 connector ties directly to the battery pack, allowing loads exceeding 400 watts for hobby equipment such as drones or robotics projects.
An ESP32-C3 microcontroller coordinates everything. It reads current data from an INA219 sensor, controls outputs, and displays status information on a 1.3-inch OLED interface navigated by three buttons. Careful circuit optimization keeps standby current under 400 microamps, ensuring the pack doesn’t slowly drain itself on a shelf.
Handling the heat generated by high power levels required custom engineering. The power modules mount to 2-millimeter aluminum heatsink plates with thermal pads, while four DS18B20 temperature sensors monitor batteries and electronics. Dual 40 mm fans activate automatically when temperatures climb.
The enclosure combines hand-cut G10 fiberglass plates with 3D-printed ABS sides and mesh-covered vents for durability and airflow. The result is a compact unit smaller than an A4 sheet of paper, yet capable of powering laptops, charging batteries, and running small tools — all from a backpack-sized package.