Just published in Newsshooter blog: http://www.newsshooter.com/2015/07/01/new-sony-a7s-professional-battery-solutions-from-hawkwoods/, hawk-woods released a dummy battery, for the Sony A7 cameras and A6000, that take the power from a NP-F550 battery.
From Hawk-woods website, here a description of their system: http://www.hawkwoods.com/blog.php?b=24
Will be a useful addition for the Sony video shooter.
