Lowes offers Kobalt 48-volt, 20-in Cordless Self-propelled Lawn Mower with (2) 24-volt, 5 Ah Battery Included Batteries Included for $299 (reg. $548) free shipping. 

Product Description:
The Kobalt 2x24V (48 Total Volts) Brushless Motor Self Propelled Lawn Mower provides superior performance without the noise, mess, and fumes of gas. The 2x24V=48 Total Volts mower offers versatility with 3-1 cutting modes along convenient push button start. Offering up to 50-minutes of cut time, the 2x24V mower has you covered. The included batteries and charger are compatible with all Kobalt 24-volt max tools and are backed by a 5-year warranty on the mower and a 3-year warranty on the batteries and charger.