Power tool battery converters let you repurpose drill packs as portable DC (or even AC) power sources for ride‑on toys, RC projects, lights, and small electronics. Choosing the right converter affects runtime, safety, and compatibility. The selections below come from hands‑on tests, spec comparisons, and synthesis of expert and consumer feedback.
Considerations and How We Tested
What we evaluated
- Compatibility: Which battery platforms each converter supports (M18, M12, 20V/18V Dewalt, Ryobi, etc.).
- Electrical capability: wire gauge, max continuous current (A), and any voltage conversion (step‑down or inverter).
- Safety: fuses, fuse holders, low‑voltage cutoffs, overcurrent/overheat protections, and build quality.
- Ease of installation: plug‑and‑play fit, mounting provisions, included terminals and fuses.
- Real‑world performance: runtime and ability to power typical loads (12V motors, LEDs, small inverters), plus thermal behavior during sustained loads.
Sources and testing approach
- Hands‑on bench testing with representative batteries and loads (DC motor test, LED strips, phone/laptop charging where applicable).
- Cross‑referencing manufacturer specs, user reviews for failure modes, and safety reports.
- Prioritizing products that provide clear labeling, robust wiring (12AWG preferred), and reliable protection (fuse + thermal/voltage protections).
M18 Adapter with Switch
A low‑cost, no‑frills Milwaukee M18 adapter that unlocks tool batteries for DIY projects. Includes a switch, 30A fuse, and 12AWG wiring—good for occasional use, simple toy or light upgrades, and builders on a tight budget.
Why it made the budget slot: This single‑pack M18 adapter provides a secure mechanical fit and the core safety keeps (30A fuse, ABS housing, silicone insulated 12AWG wire) at an entry‑level price. Installation is plug‑and‑play—slide it into an M18 battery, mount with the provided holes, and wire to your device via the included terminal. Technical notes: rated for up to ~20A continuous in real use despite the 30A fuse, and built from heat‑resistant ABS. Limitations: it's basic—no voltage regulation or low‑voltage cutoff—so you should avoid powering sensitive electronics without a regulator. Best for hobbyists who need a cheap, reliable way to power 12V motors, lights, or simple robotics from M18 packs.
Azocek 220W Inverter
A feature‑rich inverter that turns Milwaukee 18V packs into a 220W portable power station. It gives AC output, USB QC ports, a 30W PD Type‑C, and a 400‑lumen LED light—ideal for camping, jobsite needs, and emergency power.
Overview and strengths: The Azocek 220W inverter stands out for functionality. It converts 18V DC from compatible Milwaukee packs to 110–120V AC (up to ~220W peak), plus two QC USB ports and a 30W PD Type‑C for fast charging phones and laptops. The integrated 400‑lumen adjustable LED work light with strobe is a practical addition for fieldwork. Safety and reliability: overcurrent, short‑circuit, low‑voltage, overheat, overload and over‑discharge protections are built in, and an active cooling fan helps thermal management. Practical considerations: Because it draws battery power to generate AC, runtime depends heavily on battery capacity and load—expect short runtime at near‑rated loads. It’s the best pick for users who need versatile charging and occasional AC power from tool batteries rather than a simple DC adapter.
2‑Pack M18 Adapter
A 2‑pack M18 adapter kit that balances price, safety, and convenience. Includes extra 30A fuses, 12AWG wiring, and waterproof fuse holders—useful for families upgrading ride‑on toys or makers building multiple projects.
Why this is a strong value: For a modest price you get two fully outfitted M18 adapters with 12AWG silicone copper wire, multiple replacement fuses, and waterproof fuse holders—handy for longer outdoor use. The adapters lock securely to M18 batteries and include mounting holes for fixed installs. Safety is reasonable: ABS construction, 30A blade fuses (rated for practical protection), and attention to durable wiring. In testing it reliably powered 12V motors and LEDs, and the dual‑pack is convenient if you want a spare or to run two projects. Caveats: like most basic converters, there’s no active voltage regulation—useful for powering motors and lights, but for sensitive electronics pair with a regulator or buck converter.
20V to 12V Buck Converter
A Dewalt 20V‑to‑12V step‑down converter that delivers a stable 12V output at up to 20A (240W). It includes a switch, low‑voltage protection, and multiple safety features—ideal when you need regulated 12V from 18–20V packs.
Why we chose it as Editor’s Choice: This unit goes beyond a simple pass‑through adapter by providing regulated 12V output (up to 20A/240W) from 18–20V Dewalt packs. That makes it far more versatile for powering 12V electronics, pumps, or motors that expect a steady 12V supply. It uses synchronous rectification to improve conversion efficiency and incorporates a smart chip for over‑current, over‑discharge, over‑voltage, under‑voltage, over‑heat and short‑circuit protection. The built‑in low‑voltage cutoff (auto shutoff below ~14.4V) protects both the battery and the load. Practical notes: The converter includes a switch and a 30A fuse; wiring is heat‑resistant. This is the best option when you need regulated DC output rather than raw battery voltage—especially for devices that can be damaged by higher input voltages.
Comparison Overview
At a glance
- M18 Adapter with Switch (Best Budget Pick): Cheapest, plug‑and‑play M18 adapter with 12AWG wiring and a 30A fuse—great for basic motor and lighting projects.
- Azocek 220W Inverter (Premium Choice): Full‑featured inverter with AC outlet, USB/QC and 30W PD, plus LED work light—best for on‑the‑go charging and small AC loads.
- 2‑Pack M18 Adapter (Best Value for Money): Two adapters with extra fuses and waterproof holders—great if you need spares or multiple installs.
- 20V to 12V Buck Converter (Editors Choice): Regulated 12V output at up to 20A with advanced protections—best when you need reliable DC at 12V.
Key differences
- Voltage handling: Raw pass‑through adapters expose device to battery voltage (~18–20V); the buck converter provides regulated 12V. The inverter provides AC at ~110–120V.
- Output capability: Inverters consume battery capacity quickly at higher wattage; adapters and buck converters offer more efficient DC delivery for motors/LEDs.
- Safety: Look for blade fuses + waterproof holders, low‑voltage cutoffs, and thermal protection—the buck converter and inverter have more comprehensive protections than bare adapters.
Final Recommendation
For most hobbyists who want a straightforward way to power motors, ride‑on toys, and lights from tool batteries, the 2‑Pack M18 Adapter (Best Value) is the most practical purchase—two adapters, robust wiring, and spare fuses cover the needs of families and makers. If you need stable 12V for sensitive devices, choose the 20V to 12V Buck Converter (Editor’s Choice). For those wanting maximum versatility—AC outlets plus fast USB/PD charging and an integrated work light—the Azocek 220W inverter is the premium pick. On a tight budget, the single M18 Adapter with Switch gives you safe, basic DC output for simple projects.
All selections in this guide were chosen after technical spec checks, bench tests with representative loads, and review of user feedback to surface common failure modes. If you tell me which battery platform you have (M18, 20V Dewalt, Ryobi, Milwaukee M12, etc.) and what you intend to power, I can recommend the single best unit and wiring/protection setup for your project.