I know this isn't 9v related, but I have had this Maha Powerex MHC-9000 charger for over 5 years now, and it does an AMAZING JOB of charging and maintaining my AA/AAA batteries! My old Energizer 2300mah NIMH AA's lasted over 5 years because of this charger! And never use another bad battery again! This will tell you within 10 minutes if the battery is bad or not! But most importantly, it has a "Break In" function, that charges/discharges the batteries VERY SLOWLY, so that they can reach their maximum capacity after that
I wanted to get some 9v NIMH batts back in the day when I had my Lemosax and LB, but never took the bite! I looked high and low for a charger similar to the Maha MHC-9000, but for 9v batts, and I never found that similar 9v charger, if it even exists
Something with that "Break In" mode would be awesome for getting the max capacity from your 9v batteries! Sure, you could just cycle the hell out of them, but that "Break In" mode is equal to probably 10 cycles at least IMO!