These adapters work, but at what costs?
| 4 min read
You can buy a power tool adapter and use a battery with different brands. However, it’s not the best idea and could even ruin your tools.
When it comes to cordless power tools, you have several options to choose from. Unfortunately, a lot of people end up buying multiple brands with different battery packs. If you’re thinking about getting a power tool battery adapter to run a Milwaukee tool with a spare DeWALT or Snap-On battery, here’s what you need to know.
We recommend sticking to one brand so the same battery works with all your tools, but not everyone has that luxury. As a result, you can easily find a slew of cheaply made battery adapters all over the internet, but are they worth the risk?
Without going too much into the technical details, a power tool battery adapter lets you use a battery from one brand with a different brand power tool. In the example above, the adapter plugs into a DeWALT or Milwaukee 18V battery cell, transforming it into the male end of a battery that works with Ryobi tools.
Battery adapters are essentially cheap plastic with the correct contact pins to send power from a power tool battery into a different form, which fits other tools. That sounds amazing, right? Well, not so fast.
For starters, it’ll absolutely void any warranty on your tool or battery. More importantly, these power tool battery adapters only have a positive and negative pin going into the battery. In comparison, official battery packs from Snap-On, DeWALT, and others have 3-4 pins. That’s because the battery and tool talk to each other, in a sense, and have protections built-in to ensure the best performance.
These days power tools are pretty fancy. Some even come with a DRM chip ensuring it’ll only work with the same-brand battery with a matching chip. More importantly, power tools and battery packs have an electronic protection system (EPS) built-in. So what is EPS? It essentially allows for communication between battery and device, which helps protect against overheating, overvoltage, overloading, and overcharge and even prevents over-discharging.
Most tools have a battery-saver mode, which shuts down the battery when it’s not in use. These adapters don’t offer any communication between the tool and the battery, and that’s not good. You could overheat and burn up a motor or drain a battery too far and permanently damage the cells, which means it’ll never charge to 100% again.
Furthermore, I’ve tried an adapter, and even when the tool isn’t in use, it’ll continuously draw power, draining the battery. If you leave it on the adapter, the next time you use your tool, it’ll have a dead battery, potentially one so dead it won’t accept a charge.
All these adapters have a warning that says not to use them to charge your battery. That’s likely because the adapter kills any communication with the charger. I’m assuming the same communication issue exists while using tools.
When a tool isn’t talking to the battery pack properly because you’re using an adapter, all it gets is endless power to “go” without thinking about all those other protections usually in place. This means it won’t balance performance with battery usage, manage the voltage properly, or deliver the right amount of power.
Imagine using a 20V battery on a 12V tool, which is now getting too much power because your adapter isn’t allowing the two to communicate. That’s a recipe for disaster. Basically, using power tool battery adapters could potentially damage your fancy power tool or those costly extra battery packs.
I know you’re probably thinking, but wait, DeWALT and other brands sell adapters. And you’re right. DeWALT offers an 18V to 20V battery adapter for around $40. This helpful adapter allows 20V lithium-ion battery packs to run select older NiCd 18V tools. However, the company has a long list of tools it won’t work with, likely because it’s unsafe.
Power tool battery adapters absolutely work, even if you buy a cheap no-name model from Amazon. However, buying one from the actual manufacturer is very different, as it utilizes all the same contact pins and communicates the correct voltage to the tool.
You can buy an adapter that’ll fit your battery and tool, and I bet it works just fine. There are various videos all over YouTube showing precisely that. These adapters work, but it’s up to you to decide if it’s worth the risk.
Are these adapters worth buying? That’s for you to decide. Sure, it’ll save you some money in the short term, and you won’t need another battery.
However, taking that shortcut and using an adapter could eventually kill your battery or tool, negating any potential savings. You could end up needing to replace a far more expensive device. Honestly, for small cheap drills, you’re probably fine, but I certainly won’t be using adapters on any of my bigger, powerful, expensive tools.
If you use power tools daily for a profession, ensuring those tools are ready for the job is crucial, and I’d advise against adapters. We don’t recommend buying off-brand or refurbished battery packs for many of the same reasons. You want to have confidence that your tools are ready without the fear of a cheap battery running out too quickly or an overpowered adapter burning up the motor.
Power tools are expensive, and so are lithium-ion battery packs these days. I get it. If you’re looking for a solution, consider getting an affordable HART power tool from Walmart.
In closing, I have several Ryobi tools that are around ten years old that run great, and the battery packs hold enough charge to get most jobs done. If, over the years, I pushed that impact driver with a different battery and cheap adapters, do you think it’d still last ten years? That’s doubtful and not a risk I’m willing to take.