Every pro-grade lithium-ion drill has a reasonable amount of runtime, but some have more than others. To compare the runtimes of the tools listed below, I counted the number of holes each could drill through 2-by Douglas fir per charge with a 1-inch self-feeding auger bit. This task was well within the capabilities of the heavy-duty drills but was a stretch for some of the compact models, especially when their batteries neared depletion.
Each tool had a new bit and was run in low gear. I avoided knots and touched up the bits with a sharpening stone partway through the test. I ran the batteries to exhaustion (or until the electronics stopped the motor), but to avoid overheating them, I switched to a different drill after every eight holes.
I performed this test five times per drill and made use of both batteries. When the testing was done I threw out the high and low scores for each tool and averaged the remaining numbers. The results can be found in the chart below.
It's worth noting that most carpenters will never drill this many 1-inch holes in a row with a cordless tool, and that under normal conditions they could most likely work all day on a pair of batteries.
— David Frane