Power tool batteries have a lot of bad habits. ONE+ 18V Lithium-Ion Starter Kit with 2.0 Ah Battery, 4.0 Ah Battery, and Charger — $99 with free tool Two batteries are better than one. These aren’t the biggest batteries Ryobi offers, but they charge quickly, handle nicely, and work across the company’s entire arsenal of electric power tools. Grab the $99 battery kit above and add a free tool and more battery power to your arsenal. More Ryobi power tool deals