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Why You Shouldn’t Buy Off-Brand Power Tool Batteries

If it sounds too good to be true, it probably is.

Ryobi tool batteries and charger
Cory Gunther / Review Geek
While buying an off-brand or refurbished power tool battery is tempting, don't do it. Third-party packs are unreliable, can ruin your tool, and won't have good battery life.

Cordless power tools are available from several big-name brands, each using its own expensive battery system. Walk down any hardware tool aisle, and take your pick. But no matter what power tool brand you use, you shouldn’t buy off-brand battery packs.

Fans of DeWALT, Ryobi, Milwaukee, Snap-On, Makita, and more will quickly realize that batteries are one of the most expensive aspects of any power tool collection. If you’re asking yourself, “do my tools need official batteries?” the answer is yes.

No one wants to spend $100 or more for a pair of battery packs, myself included. And while I know it can be tempting to snag a no-name power tool battery online or find a refurbished (rebuilt) battery, it’s not worth the risks or wasting your hard-earned money.

Battery Types and Design

18V Li-ion power tool battery pack.
Nina Unruh/Shutterstock.com

Getting the correct power tool battery is easy when it’s from DeWALT or Ryobi, but when you look elsewhere, it’s risky. There are different battery types, voltages, ratings, designs, and more, and you’ll want to ensure you get the right kind.

The most widely-available battery is lithium-ion (Li-ion). However, older power tools used nickel-cadmium batteries (NiCad), and Nickel Metal Hydride (NiMH) batteries were popular for a while for being more affordable than Li-ion along with solid power output. These days, you’ll want Li-ion.

You know what you’re getting when you buy a battery from a reputable brand. If you find some random no-namer on Amazon that looks like a Ryobi battery pack, it’s hard to know if it’s lithium-ion, even if the sticker says so. You have no clue what the actual battery type is.

Power tool battery packs also have different ampere ratings (like a 4 Ah battery pack) and other specs, which is just as important. And that’s without considering the design and connector, how well it’ll fit not one—but all—of your brand of tools, and how well it’ll communicate with the device to ensure the best experience and proper power output. Plus, once you buy one battery, it’ll work with a slew of tools from that brand, so stick to the same brand for everything.

Components, Voltage, and Capacity

Milwaukee power tools in a table.

There are several reasons to avoid third-party power tool battery packs, from the internal components, voltage, battery capacity, and more. While getting the correct cell type and design is essential, as mentioned above, ensuring the battery is of the proper quality and voltage is a big deal too.

In case you didn’t know, not all lithium-ion cells are created equal. The components inside an OEM battery from a name brand will be high quality, have strict quality control, and last longer than any cheapy one you find online. Third-party battery packs are likely using cheaper cells or recycled goods to lower costs and won’t deliver the same experience.

Additionally, those cheaper components have a higher risk of failure. Even if it claims the same 4 Ah capacity, it won’t last as long as an official battery during daily use, nor hold its charge as long. Combine lower-quality battery cells with no internal overcharge or overvolt protections as you get on an OEM battery spells trouble. You could even kill a knockoff battery while it’s on the charger.

More importantly, each power tool manufacturer has specific battery voltages for each tool. Some are 12V, 18V, 20V, or even 40V. Those voltage levels are important to the overall experience.

Using a third-party battery that doesn’t follow the manufacturer’s guidelines (or matches the voltage rating) can lead to overcharging. One could send too much power to your drill or impact wrench, potentially burning up a tool’s motor if it’s not getting the proper current.

I’ve seen a no-name battery start melting, killing itself and the power tool. And the second battery in that “affordable 2-pack” I bought online failed within the first month. I learned that the hard way, so take it from me, get official battery packs. You’ve been warned.

Tips to Improve Power Tool Battery Life

DeWALT power tool battery 2-pack.

Whether you already have multiple cordless power tool batteries or recently bought more, the next thing you’ll want to know is how to preserve the battery’s life. You can take several steps to ensure they last longer and work their best.

Like lithium-ion batteries in your smartphone, power tool batteries will start to hold less of a charge and degrade over time. This is due to the makeup on the inside, but other factors like charging, storage, and temperate will also affect the life of the battery.

First off, don’t overcharge your power tool battery pack. Many owners leave a battery on the charger 24/7 and only take it off when needed. That’s a habit you’ll want to break. Leaving the battery on the charger all the time can lead to overcharging, additional heat, and degradation. But don’t store it on empty, as that’s bad for the battery too.

Another common mistake is using your power tool until the battery dies, then instantly throwing it on the charger so you can get enough juice to finish the job. All power tool brands recommend letting the battery pack cool between use and charging.

Lithium-ion likes to stay in the same temperature range as humans, especially when charging, so letting it cool down first can enhance the life of your battery pack. The same goes for the cold. Charging your power tool battery out in the cold isn’t a good idea, and it’ll recharge slower. Additionally, don’t leave a battery pack (especially on empty) sitting in a cold storage shed over the winter. Bring it in the garage, or better yet, inside the house with a 60-80% charge. 

Have you ever left your phone in the car during cold winter months or on a hot summer day and noticed the battery depleted? The same happens to power tool batteries, so take care of them.

Over time and with heavy usage, all battery packs will eventually hold less charge and not be as effective. Follow these steps to prolong the life of your battery, and when the time comes, get an official battery from your brand of choice.

Cory Gunther Cory Gunther
Cory Gunther has been writing about phones, Android, cars, and technology in general for over a decade. He's a staff writer for Review Geek covering roundups, EVs, and news. He's previously written for GottaBeMobile, SlashGear, AndroidCentral, and InputMag, and he's written over 9,000 articles. Read Full Bio »