Common Problems With DeWalt's 18V To 20V Adapter (According To Users)

Cordless tools are undoubtedly more convenient than their corded counterparts, but they also come with a degree of built-in obsolescence. They rely on proprietary battery packs to function as intended, and when those battery packs are discontinued, users can be faced with the prospect of either relying on their aging original battery packs or shelling out for entirely new tools. DeWalt discontinued its 18V battery line several years ago in favor of expanding its 20V line, but rather than forcing users to buy new 20V tools, the brand unveiled the 20V Max Battery 18V Adapter Kit.

It's designed to let 18V tool owners use the latest 20V batteries with their older tools, and it looks like a good deal at first glance for 18V tool owners. It includes two 20V Max batteries, a charger, and an adapter to connect the batteries to 18V tools. However, the kit has a dismal average rating of just 2.7 out of five stars from reviewers on DeWalt's website, with a handful of common issues being chiefly responsible for that rating. One of the most common complaints among reviewers is that the included batteries don't hold charge for as long as older 18V batteries did. 

Many say that leaving the batteries in the adapter can leave them dead in just a couple days, while others note that even freshly charged batteries offer a much shorter life than the 18V packs that owners previously relied upon. And it's not like the adapter kit is cheap either. At the time of writing, it's $199 from Lowe's and $229 at Ace Hardware. Buyers who already have suitable 20V batteries and a charger to hand can purchase the adapter separately for $59 at Lowe's.

Alongside the diminished battery life, another common complaint is that the adapter is very hard to remove from the tool. That reportedly makes swapping the battery pack between tools a chore, with some reviewers reporting that the tabs that keep the adapter in place are so tight that they have had to resort to using other tools to open them.

However, others disagree, saying that the adapter isn't any more difficult to remove than other tool attachments. It's not clear whether the difference in opinion is down to the adapter fitting differently in particular tools or whether it's a quality control issue that has seen some adapter tabs manufactured to be tighter fitting than others. Either way, the mixed messaging hardly inspires confidence in the product.

Reviewers have also pointed out other issues with the adapter and its associated kit. Some point out that certain 18V tools cannot be used with the adapter, such as the DC759 and DC970. Other reviewers report that the batteries included with the tool degrade quickly, or that they no longer charge to full after a few uses.

Some reviewers acknowledge these issues but still leave a positive rating for the adapter kit. They note that, despite its flaws, using the adapter is one of the only viable ways to give a second life to 18V DeWalt tools. Attempting to refurbish or rebuild older DeWalt batteries isn't generally advisable, and knock-off DeWalt 18V batteries can potentially pose a safety hazard. However, for other potential buyers, the limitations might be enough to put them off the adapter altogether, even if that means they have to give up on using their older 18V DeWalt tools.

To find clear, comprehensive feedback about the common issues with the adapter and its associated kit, we headed to DeWalt's website to see what buyers had to say about the product. All of the issues cited above were highlighted by multiple reviews. This is not intended to be a direct recommendation of whether or not to buy the product, but instead to be a quick summary of the product's drawbacks that have been highlighted by owners.