M18 Battery Holder — Covered Terminal Protection

Full-cover battery holder that actually protects your terminals.

Most M18 battery holders leave the terminals exposed. This one fully encloses the battery including the terminal face — so it doubles as a terminal protector when batteries are stored or transported. Many of the others are also just blocks with a slot in them: weak, unimaginative and awkward to use. This one is built for strength, with an angle that makes the battery easy to put in and take out.

Uses Milwaukee's own push-lock mechanism — batteries click in and release the same way they do on your tools. No friction fit, no worrying about batteries working loose over time.

Built-in 10° angle for ergonomic access. Fits ALL M18 batteries from compact 2.0Ah up to 12.0Ah High Output.

Designed by MBKing (Mogensbæk Engineering), Denmark. Originally designed in 2020, tested in real work environments for 3+ years.

3 STL VARIANTS INCLUDED

This listing includes 3 versions of the battery holder so you can choose the approach that suits your setup:

1. No Supports Print as-is. You'll get minor sagging on the bridge and the top of screw holes — totally functional, just cosmetic. Or use your slicer's built-in support settings if you prefer.

2. Custom Bridge Support (recommended) This is what I use for production. A custom support body is included that gives you a perfect bridge on the underside. For best results, use a high Bridge Flow Ratio and slow External Bridge Printing Speed in your slicer. See photos for the result.

Printing this model with custom support, i split the part into objects. Then i print the support with 2 perimeters, 4 top- and 3 bottom layers. Also for the support i enable the “Precise Z-Height” option.

3. Custom Experimental Support Includes the bridge support plus custom support geometry for the screw holes. The full top half of each hole is supported with an offset geometry that is 0.15mm smaller in Z. This is not easy to print in PETG — use at your own risk.
Printing this model with custom support, i split the part into objects. Then i print the support with 3 perimeters, 4 top- and 3 bottom layers. Also for the support i enable the “Precise Z-Height” option.

RECOMMENDED PRINT SETTINGS

These settings give the best balance of strength, durability, and chemical resistance:

• Material: PETG recommended

• Perimeters/walls: 4

• Top/bottom layers: 8

• Infill: 15% (gyroid, grid, or crosshatch)

• Layer height: 0.2mm

• Supports: None needed (use variant 1), or use the included custom support bodies (variants 2 and 3)

This is a forgiving design — it will hold up fine with different materials and settings. But for the best result, follow the recommendations above.

Print hot enough that the surface has a slight glossy/shiny finish. If your print looks matte, your temperature is too low and you'll get weaker layer adhesion.

HARDWARE

3x stainless steel A2 screws for wall mounting (M4x20 and M4x25 or similar — not included in download).

MORE FROM MBKING
 🔒 M18 Locking Tool Holder — The only Milwaukee M18 holder with a true mechanical lock. Pull-tab mechanism, tested in work vans for 3+ years. Zero failures over 100+ prints. → STL available on Etsy: mbkingmarket.etsy.com
🔧 M12 Adjustable Holders — Clever toothed hinge mechanism that fits ALL M12 tools and batteries. Wall, ceiling, under-shelf — you set the angle. → Available on Etsy: mbkingmarket.etsy.com
Full range of physical holders — Premium PETG with stainless steel hardware, shipped within EU. → mbkingmarket.etsy.com