This isn't to be confused with amp-hours (Ah), which determines how long a battery holds its charge while in operation. Ryobi's regular 40V batteries are designed for use in more power-hungry ...

For example, if you have a 40-volt Ryobi battery laying around and the battery for an 18-volt tool gets lost or dies, you may wonder if you can put the 40V battery in the 18V tool. Sadly ...