Kensington PowerLift Back-Up Battery and Dock Announced at CES 2011 Xavier Lanier01/06/2011 Kensington introduced the PowerLift Back-Up Battery and Dock at CES 2011 today. The device plugs into an AC adapter, charging your iPhone while at home or at work. While it’s plugged into the wall, the PowerLift’s 1200 mah battery, which can provide up to 3.5 hours of talk time. Advertisement The PowerLift looks pretty versatile, but talking on an iPhone while charging it with the PowerLIft looks a little awkward in this video. The PowerLift Back-Up Battery and Dock has an MSRP of $49.99.