The lithium-ion battery powers the clean butler 4g silent cordless vacuum cleaner completely independently of the mains and allows maximum mobility without annoying cable tangle or tedious plugging. The rechargeable battery is simply inserted into the battery compartment of the clean butler 4g silent and charges itself while the vacuum cleaner is connected to the mains. The 22.2 v / 2,200 mah lithium-ion battery pack takes approximately 4 hours to charge and can provide 25-30 minutes of continuous run time. Convenient vacuuming throughout the entire apartment without cable clutter and plugging - the clean butler 4g silent lithium-ion battery is the ideal accessory item if you ever need to use the cordless vacuum cleaner for a little longer. The clean butler 4g silent lithium-ion battery is the matching accessory for the clean butler 4g silent cordless vacuum cleaner.