While there are already battery cases on the market for the iPhone X, Mophie has filed an application with the Wireless Power Consortium to offer the first one that is Qi-certified, Mac Otakara reports. Today Mophie was granted the Qi certification for its Juice Pack Air for iPhone X, so an official announcement could be forthcoming any time. The filing claims the device will be able to extend call duration by up to 9 hours, but doesn’t include…