3x18650 DIY Power Bank Case — Dual USB Fast Charge with LED Night Light

Build Your Own Power Bank. Your Cells. Your Capacity.

The 3x18650 DIY Power Bank Case puts you in control of your portable charging setup. Load it with three 18650 lithium-ion cells of your choice, and you've got a dual USB fast-charge power bank with a built-in LED night light — customized to exactly the capacity you want. Replace the cells when they wear out instead of throwing away the whole unit. It's the smarter, more sustainable way to build portable power.

Key Benefits

• 3x18650 Cell Capacity — use your own 18650 cells to set your preferred capacity; upgrade anytime
• Dual USB-A Output at 5V/2A — fast charge two devices simultaneously from a single case
• LED Night Light — built-in LED doubles as a portable night light or emergency flashlight
• Replaceable Cells — swap out worn cells instead of replacing the entire unit; more sustainable and cost-effective
• Compact Shell — lightweight, pocket-friendly design that doesn't add unnecessary bulk
• Wide Cell Compatibility — works with standard 18650 lithium-ion cells from most major brands

Whether you're a DIY electronics enthusiast, a prepper building a custom power kit, or just someone who wants a power bank with replaceable cells — this case delivers. Load it with high-capacity 18650 cells for maximum runtime, or use cells you already have on hand. When they wear out, swap them. No waste. No replacement cost. Just reliable portable power on your terms.

Frequently Asked Questions

Do 18650 cells come included?
No — 18650 cells are not included. You'll need to source three 18650 lithium-ion cells separately. Most major battery brands are compatible.

What capacity can I achieve?
Capacity depends on the 18650 cells you use. Three 3500mAh cells would yield approximately 10,500mAh theoretical capacity (actual delivered capacity will be lower due to conversion efficiency).

Can it charge two devices at the same time?
Yes — dual USB-A outputs at 5V/2A allow simultaneous fast charging of two devices.

How do I replace the cells?
Open the case, remove the old cells, and insert new 18650 cells with correct polarity. No soldering required.

Is the LED night light always on?
No — the LED night light is typically activated by a separate button or switch. Check the product for specific operation details.

SPECIFICATIONS

Cell Type: 3x 18650 lithium-ion (not included)
Output: Dual USB-A, 5V/2A
Additional Features: LED night light
Design: Compact, replaceable-cell shell
Compatibility: Standard 18650 cells
Weight: 0.17 lbs / 0.079 kg (without cells)