How to Use a Dewalt Battery on Makita Tools – A Step-by-Step Guide
We've all been there. You're halfway through cutting deck boards, and your Makita 18V saw just went flat. You check your toolbox—three Dewalt 20V batteries, all fully charged. But they don't fit. The slides are different, the terminals don't align, and the voltage ratings aren't the same.
But here's the good news: yes, you can use a Dewalt battery on a Makita tool. It just needs the right adapter and a little know-how.
I've been running cross-brand setups on job sites for the better part of a decade, and I'll walk you through exactly how to do it safely—no smoke, no sparks, no ruined tools.
What You'll Need
Before you start, grab these:
- A Dewalt 20V Max battery (any capacity—3.0Ah, 5.0Ah, even the 9.0Ah high-capacity packs all work)
- A Makita 18V LXT tool (drill, impact driver, circular saw, recip saw—any Makita tool with the LXT slide mount)
- A Dewalt-to-Makita battery adapter (available online for $10–$20)
- Safety glasses (always)
- A clean, dry work surface
The adapter is a small plastic block with Dewalt-style slides on the bottom and Makita-style slides on top. It's a passive device—no electronics, no BMS reprogramming—just a physical shape converter. That's important, because it means your tool's safety systems stay fully in control.
Quick note on voltage: A Dewalt 20V Max battery is actually an 18V nominal battery (they call it "20V Max" for marketing—it peaks at 20V, but runs at 18V). A Makita 18V LXT battery is also 18V nominal. So voltage-wise, they're a match. No over-voltage issues.
Step 1 – Choose the Right Adapter
Not all adapters are created equal. I've burned through cheap ones that cracked under the weight of a 9.0Ah pack. Here's what to look for:
- Material: Choose nylon-reinforced or ABS plastic—avoid the brittle clear-plastic ones.
- Fitment: Make sure it says "Dewalt 20V to Makita 18V" (or "Dewalt XR to Makita LXT"). A loose adapter will wobble and lose connection mid-cut.
- Terminals: Look for gold-plated or copper contacts—they resist corrosion and conduct better.
- Brand: SKYHIGHNINE and BATTOP make reliable ones. The no-name $6 ones are hit-or-miss.
I keep an adapter in my truck for exactly this scenario. It's saved me from driving to the charger more times than I can count.
Step 2 – Attach the Adapter to Your Dewalt Battery
This part's straightforward, but do it right:
- Align the Dewalt battery's slide rails with the adapter's grooves. Dewalt batteries have that distinctive Y-shaped slide profile—make sure it's seated all the way.
- Push firmly until you hear the adapter click into place. The release button should pop up cleanly.
- Give it a gentle tug to confirm it's locked. If it slides, it's not fully seated.
Common mistake: People try to force the battery onto the adapter at an angle. Don't. Line it up straight and push evenly. Crooked installation can bend the terminal blades.
Step 3 – Mount the Combo onto Your Makita Tool
Now take your Dewalt-battery-with-adapter assembly and attach it to your Makita tool:
- Line up the adapter's Makita-style rails with your tool's battery slot.
- Slide it forward until it clicks.
- Give it a firm push—Makita tools have a spring-loaded lock that engages at the very end. If it feels loose, push harder.
You'll know it's seated when the battery sits flush against the tool's base and doesn't wobble.
Real talk: The adapter adds about ¾ of an inch to the overall height. It's negligible on a drill or impact driver, but on a circular saw, it might change the balance slightly. You'll get used to it after a few cuts.
Step 4 – Test and Operate
Before you start your actual work, do a quick bench test:
- Squeeze the trigger briefly—the tool should power up immediately.
- Run it at low speed for a few seconds. Listen for any stuttering or hesitation.
- Check the connection point—it should feel cool to the touch. If it gets warm instantly, stop and reseat everything.
If everything checks out, you're good to go. Run the tool normally. The Makita tool's internal electronics (current limiting, over-discharge protection) will manage the battery just as it would a Makita-brand pack.
Safety note: Don't use an adapter with tools that draw sustained high current for long periods—like a grinder or a concrete saw. Adapters add resistance at the connection point, and sustained heavy draws can heat up the contacts. For intermittent use (drilling, driving, cutting wood), it's perfectly fine.
If you're looking for dedicated batteries that fit without adapters, check out our batteries compatible with Makita tools or our Dewalt 20V replacement batteries for when you want a direct-fit solution.
Common Mistakes to Avoid
I've seen plenty of guys on site screw this up. Here's what not to do:
1. Using a voltage converter instead of a passive adapter.
Some adapters claim to "step down" voltage—stay away from those. They add an extra point of failure. A passive adapter that just changes the physical shape is all you need since the voltages match.
2. Mixing 60V Dewalt batteries with 18V Makita tools.
Dewalt's FlexVolt batteries run at 60V (54V nominal) and WILL fry a Makita 18V tool unless the adapter includes a voltage regulator. Stick to Dewalt 20V Max batteries only.
3. Leaving the adapter on the tool when not in use.
If you leave the adapter mounted, it's easy to grab a Makita battery and try to jam it onto the adapter—which doesn't work and can damage the terminals. Remove the adapter when you're done.
4. Using an adapter with wet tools in the rain.
Most adapters aren't sealed. If water gets between the adapter and the battery terminals, you're asking for a short. Keep your adapter setup dry.
5. Running the battery all the way to zero.
Cross-brand adapters don't always trip the low-voltage cutoff perfectly. I recommend swapping to a fresh battery when the tool starts feeling sluggish—don't run it to dead silence.
Frequently Asked Questions
Q: Will using a Dewalt battery on a Makita tool void my warranty?
A: On the tool side—maybe. Makita typically won't cover damage from third-party accessories. On the battery side, using it on a non-Dewalt tool could void the battery warranty too. Use at your own discretion. That said, thousands of guys do this daily without issues.
Q: Does the adapter affect the tool's power or runtime?
A: Runtime is the same since the battery capacity doesn't change. Power output is nearly identical—the adapter's contact resistance is minimal (under 0.1 ohm on quality units). You won't notice a difference in torque or speed.
Q: Can I charge the Dewalt battery while it's still in the adapter?
A: No. Remove the battery from the adapter before charging. The adapter blocks the Dewalt charger's sense pin alignment, and the charger won't recognize the battery.
Q: Will a Dewalt 9.0Ah battery fit on a Makita compact drill?
A: Physically yes, but it'll be top-heavy. The 9.0Ah packs are big. For compact tools like drills and impact drivers, stick to 3.0–5.0Ah Dewalt batteries—they balance better.
Q: Do I need a different adapter for Makita 40V XGT tools?
A: Yes. This guide is for Makita 18V LXT tools. The Makita 40V XGT platform uses a completely different slide design and voltage. Don't try to adapt a Dewalt 20V battery to an XGT tool—it won't work.
Got questions about which batteries pair best with your tools? Reach out to our support team—we're happy to help you find the right fit for your kit.
If you’re still deciding between platforms, our Dewalt vs Milwaukee vs Makita comparison breaks down which battery system suits your work best.