As far as I'm aware F. are still using Samsungs, but someone with a bit more tech expertise can confirm or refute this. I recently came across a table that outlined the various manufacturer's & OEM suppliers & users battery cell brand & type fitment, but can't readily find it again.
The "ProCore", Core, Li-HD & Panasonic sellers are using Sanyo 20700 cells. They're different, not just in capacity but also in charge/discharge characteristics too. Plainly put, they'll take & give significantly greater current flow than others on the market. One extreme example is the Bosch 3-row 12.0 AH batteries that can supposedly deliver some 90A of peak current!
I'm currently using 5 Sanyo 20700 equipped batteries myself, & can confirm that they do indeed deliver greater current flow than "conventional" battery cells can. The difference in high current draw devices is immediately noticeable, however the effect is much less, if at all noticeable in lower powered devices. After 2 years use they're stable & reliable enough for me to consider purchasing another 4 batteries in the near future. As the individual cells are slightly longer & fatter than "conventional" cells, the resultant batteries may not necessarily physically fit all devices designed for an earlier generation. I've personally only had issues with an internal battery bay in a Radio so far.
As for the abilities or opportunity for "crossover" between cell manufacturers/chemistries/brands I simply don't have any appropriate expertise to comment, but would suggest that for operational & contractual reasons it's unlikely. Compatibility issues could be around the physical & electronic interface differences, charging sinewaves & internal architecture & cooling aerodynamics.
High charge & discharge currents generate significant heat, which requires particular attention to be paid to cooling pathways, air velocity and circulation pressure. Undoubtedly Samsung will eventually market greater capacity &/or current cells & updated charging technology, but going on past performance Festool are anything but early adopters of new-gen battery tech. Given that Sanyo-Pana are marketing 4.0, 8.0 & 12.0 AH capacity batteries in 1, 2 & 3 row configurations already, and plan for 4.5, 9.0 & 13.5 AH versions to be released in 2019, Samsung & their OEM customers have quite a bit of catching up to do.
