DIY Power Bank Box Case for 4x18650 Batteries – Custom Capacity with LCD Display and Dual Inputs

Building your own portable power bank gives you full control over battery quality and capacity. This DIY power bank box case accepts four 18650 li-ion batteries, letting you avoid fakes and inferior cells. It doubles as a battery charger, making it a practical dual-use item. The compact 100x84x26mm case includes an LCD display that shows remaining capacity for each battery individually, plus dual inputs for convenient charging. Whether you need a reliable external supply for travel or a custom backup for gadgets, this case delivers flexibility and peace of mind.

Features and Construction

This power bank box is designed for practical, safe, and customisable use. Its independent circuit and reverse polarity protection ensure stable operation even with mismatched batteries.

Independent Circuit Design

Each battery charges and discharges independently, so they can work together without interfering. This means you can charge the power bank and power a device at the same time, with the LCD showing each cell's level individually.

Reverse Polarity Protection

If a battery is inserted the wrong way, the internal chip automatically cuts power to that circuit and displays an empty battery level. Other circuits continue to operate normally, protecting both the case and your batteries.

LCD Display Screen

The LCD screen clearly shows the remaining capacity for each of the four batteries individually. This makes it easy to monitor battery health and know when to recharge without guesswork.

Uses and Placement

This case is ideal for anyone who wants a custom-power solution without the hassle of transporting built-in batteries. Use it as a portable power bank or a dedicated 18650 charger.

DIY Power Bank Building

Choose your own 18650 batteries to match your capacity needs. Whether you want a lightweight daily pack or a high-capacity backup, you control the build. The dual outputs let you charge two devices at once, like a phone and a tablet.

Battery Charger Function

Use the dual inputs (8 Pin and Micro USB) to charge your 18650 batteries directly. One cable is all you need to charge the power bank, making it a convenient all-in-one charger and power station.

Benefits and Buying Value

This product avoids the risks of pre-built power banks with unknown or fake batteries. You get guaranteed quality and custom capacity at a low upfront cost.

Reuse and Low Maintenance

Because you supply the batteries, you can replace them individually when they wear out. The case itself is durable and reusable, saving money over disposable power banks.

Why Choose This Product

You decide the capacity and battery core, rejecting false capacity and low-quality cells. The dual inputs and outputs, independent circuit, and LCD display add professional-level features to a simple DIY project. Available in Black or White.