Posted by Jeff Somers

https://lifehacker.com/home/cordless-power-tool-battery-adapters?utm_medium=RSS

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When shopping for cordless power tools, you'd think you could simply purchase the best option of each to fit your needs. But there's a big problem that makes this a lot harder (and more expensive) than it should be: battery incompatibility. By design, you can’t simply pop a Ryobi battery into a DeWalt tool and expect it to work. Engineering decisions aside, using proprietary batteries allows companies to create a sort of obligatory brand loyalty, forcing you to stick with their line of tools unless you want to invest in a whole new set of batteries for every new tool you buy.

If you've been building your cordless tool collection for some time, you may wind up with four or five different chargers and multiple batteries cluttering your workspace. And that clutter can be expensive, because you wind up buying more chargers and batteries than you might not need if batteries were interchangeable.

But it turns out they are, sort of. You can actually swap batteries between brands—you just need the right adapters.

Adapters let you swap tool batteries between brands

There are two kinds of battery adapters to consider:

• Inter-brand adapters allow you to use one brand’s batteries in another brand’s tool (like DeWalt batteries in Milwaukee tools).

• Voltage adapters allow you to use a different voltage battery than the tool expects (say, a 20-volt battery in a 18-volt tool).

These adapters are a fairly simple solution to the problem of incompatible battery systems. If you have a lot of DeWalt tools, for example, you can purchase a Milwaukee tool without a battery (which will be cheaper) and just use an adapter to plug in one of the DeWalt batteries you already have.

Of course, these batteries weren’t specifically designed for these tools, so there can be some trade-offs. While tool performance has been found to be broadly similar (and some tools even performed better when using batteries from different brands), for some tools (like grinders and some circular saws) there’s a dropoff in power and performance when using an adapter. That said, you might not notice it if you're just looking to tackling simple DIY projects around the house.

Another caveat to consider: You might lose some features. Some tools are designed to communicate with the battery to modulate power draw in order to extend the life of the battery, and using an adapter will remove this functionality. But again, if you’re simply using a power drill for basic maintenance tasks, this might not be a huge issue for you.

Universal adapters are a good solution if you own a bunch of brands

If you’ve got a bunch of disparate tool brands, of course, buying multiple adapters might not seem like much of an improvement over your collection of batteries and chargers. If this is you, consider something like the Ceenr PDNation Universal Battery System, which provides an 18-volt battery and a series of adapters that allow it to be used in a wide range of power tools, including major brands like Ryobi, Milwaukee, and DeWalt.

For example, you can buy a battery with an adapter for DeWalt tools, then buy a second adapter for the same battery that will work with Makita tools. This means you can standardize on one battery system for pretty much any tool you buy (it’s not a truly universal system, since you’re dependent on the range of adapters they offer, but it’s probably close enough for most people).

As with other adapters, there can be some performance loss using a universal adapter, but by and large, it’s probably not a big issue if you’re doing work around the house, as opposed to working professionally on a job site.

https://lifehacker.com/home/cordless-power-tool-battery-adapters?utm_medium=RSS

Posted by Beth Skwarecki

https://lifehacker.com/health/oura-ring-new-charging-case?utm_medium=RSS

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Oura has finally answered my biggest (yet perhaps pettiest) complaint about its iconic smart ring—it’s now getting a battery-powered charging case so you can top up the battery when you’re away from your home. The company first announced this back in October, but the charging case is now finally on sale. It's $99 and you need to make sure you order the size that matches your ring size.

The charging case is specific to the Oura ring 4. If you have a gen 3 ring, there are a few third-party charging cases available, like this one, as well as cases that can house your existing Oura charger of either version, like this one.

Along with the charging case, Oura's October announcement included new ring colors available in a ceramic finish, and finally, multi-ring support so you can switch between rings. At the same time, Oura also announced Health Panels, a feature that lets you book a blood draw at a Quest lab and view your results in the Oura app. Whoop had previously announced a similar feature, and Ultrahuman launched its Blood Vision earlier in 2025. 

Why I’m excited for the charging case

In all the time that I’ve been using Oura rings—since generation 2—the charger has worked the same way: You have a little circular stand that lives on your nightstand, and you set the ring on top of it, fitting it around a little cylinder shape that sticks up from the base. I’ve never loved this format; it’s too easy to send the ring flying if you catch your foot on the cord in the dark. It’s also not the most convenient for travel. 

Now, however, the Oura ring has a charging case. The case holds about five charges’ worth of battery, so you can top up the charge on your ring by popping it into the case, then closing the case and sticking it in your pocket. Or gym bag. (Weightlifting workouts are my favorite time to charge the ring.) Traveling with the charger is now simple, and you don’t have to worry about losing the ring if the charger gets knocked over. Other ring brands have been making their own charging cases in the meantime. RingConn comes with a charging case; so does the Luna ring that I'm reviewing now.

Now for the bad news: This puppy is $99, and it’s a separate add-on; you can’t get it in place of the nightstand charger when buying a new ring. Like the nightstand chargers, it’s specific to the size of your ring. For example, you need a size 8 charger for a size 8 ring. The new charging case doesn’t seem to be available on Oura’s website yet, but it should be coming soon. (If you can’t wait, or want to save a few bucks, I found this third-party case that holds your nightstand charger—either generation 3 or 4. It's not as sleek as the official one, though.) 

You can now swap between rings

Today Oura announced a new collection of ceramic rings in four different colors: white, navy, pastel green, and pink. The new rings have the same internals as the metallic Ring 4, so this isn’t a new generation of ring, just a new appearance. (Oura also notes that the ceramic rings should be more resistant to scratches, and each one comes with a polishing pad to keep its shine.) All colors are $499, the same price as the gold and rose gold finishes of the regular Ring 4.

With so many color options, Oura seems to hope existing members will splurge on a second ring. The company is rolling out multi-ring support for the app, another feature I'm surprised they didn’t have before. (When I’ve tested the gen 3 and 4 rings to compare, I've had to completely reset my ring to switch over, or else use two different accounts.) Oura says you’ll need to select in the app which one you’re wearing, so it’s not quite as seamless as the way Garmin or Apple handles multiple devices. (Garmin has me choose a “priority device” and then I can switch at will; Apple just sets you free to swap as you like, and it does its best). 

If you are done with your old ring after upgrading, Oura now has a ring recycling service that gives you a shipping label to send back your old ring. Any Oura ring can be recycled through this program, including old or broken ones. (You should factory-reset the ring first.) Rings you recycle won’t be eligible for returns or refunds.

https://lifehacker.com/health/oura-ring-new-charging-case?utm_medium=RSS