I predict this is true. They'll make battery power wireless then it will become cloud-based and then you'll have to subscribe if you "need" longer than the 10 minutes of local battery. Gotta love the subscription model...
Eventually the charging mechanism may be wireless, or a platform instead of a plug-in, but the batteries will remain. Overall, the battery technology will improve giving more power in a lighter battery, and the consumption by the processor+GPU will be less, with greater performance overall, as we see here. You will get like a week of use out of your laptop without having to charge it once, and standby will last 3 months.