40x18650 Battery Holder Power Enclosure for Portable Electronics Builds

D40 40-Cell 18650 Power Bank Enclosure Kit

The D40 is a large DIY power-bank enclosure designed to hold up to 40 user-supplied 18650 cells. It combines a removable cell compartment with an integrated power-bank control board, display and rear work light. This listing is for the enclosure and its installed electronics; 18650 cells are not included.

Select the Correct Version

• D40 black / D40 white: standard enclosure version in the selected colour.
• D40-PD black / D40-PD white: PD-labelled version in the selected colour.
• D40-PD-QI black / D40-PD-QI white: PD-labelled version with the QI wireless-charging feature shown on the front panel.
• Feature set and colour follow the selected variant. Do not assume a function shown for one version is included with another.

Assembly Notes

• Install only matched, undamaged 18650 lithium-ion cells of the same chemistry, condition and capacity. Do not mix old and new cells or cells with different charge states.
• Follow the polarity marks in every bay. Inspect cell wraps and insulators before installation; never insert damaged or exposed cells.
• The enclosure is not a battery pack until compatible cells have been correctly installed. Capacity, available output and charging performance depend on the cells and the selected enclosure version.
• Use the enclosure only with the cover installed and discontinue use if it overheats, smells unusual, is physically damaged or shows abnormal charging behaviour.

What Is Included

• D40 power-bank enclosure with installed electronics, display and the functions associated with the selected variant.
• 18650 cells, charging cable and external devices are not included unless explicitly stated at checkout.