The vac includes a 2000ma battery. The motor is rated for 8amps draw (87w), which if you plug in those numbers to: https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-battery-life, you get 15m. Of course if you use the pet powered brush, it consumes ‘12w’ as rated by its sticker. That’s 1.1a additional, bringing our calculated runtime down to 13m. Empirically - that bears out - as I’ve gotten about 15m of runtime before it shuts down without the pet brush. I haven’t used the pet brush longer than 10m, but I’d assume it’d be pushing near the bottom fifth of the battery.
It’s just cool to see the math, and designed capacities bear out in real life. As with any lithium battery, it will lose capacity over time, but hopefully it’ll last much better than the old NiCad batteries of yesteryear. Hopefully this helps!