Zpower MBP 17 perhaps MBA
I'm not sure if this discussion is leading us in the direction of the 'new battery tech' being ZPOWER's Silver-Zinc technology perhaps being used in the new MBP 17 or an updated MBA.
But from reading about the ZPOWER battery they are trying to control the usually high cost of the silver component in their battery with a mandatory recycling program.
"...ZPower plan to reduce the cost by a trade-in policy that will reduce the cast of mining new material. As 95% of the material is recyclable most of the raw material is recovered and as per ZPower the process used also makes sure that the quality of the material is maintained...."
Source:
http://jedi-star.com/index.php/long-lasting-laptop-batteries/
That would make a non-user replaceable battery almost a given, since they are counting on you or Apple returning it at some point (if indeed this is the battery that Apple uses in it's new MBP).
If the battery really does last longer and and be recharged quicker it would be a terrific battery for the MBA certainly (already non-user replaceable, why not last longer ?)
Now onto the MBP 17. I regularly observe the use of the MBP 17 in a client's medical office. They either have to plug it in for a portion of the day or replace the battery. They have 2 batteries for each MBP. They are always swapping batteries on their smaller non-Apple laptops as well (Fujitsu, Acer). A non-replaceable battery could hinder their ability to use the laptop, unless it lasted the whole time the doctor is carrying it from room to room seeing patients. Perhaps from 8 ~ 12, short break for lunch, perhaps some recharging, then again from 1 ~ 5. It would be amazing if it could last for 8 hours of use including wireless usage.