Wow, just when the Maha Superex 1800 mAh rechargeable AA batteries are all the rage at Thomas Distributing... and the Energizer 1700 mAh batteries hold their own against the Maha 1800's...
WHAM!! Energizer has just upped the capacity of its NiMH AA's to 1850 mAh!! But be careful if you have an older NiMH-compatible charger: You may find that your older NiMH-compatible charger doesn't fully charge the newer 1800+ mAh batteries, since they were designed when all AA NiMH's had a rated capacity of only 1200 mAh. Which means that if you have an early NiMH-compatible charger that's timer controlled, you'll find that it doesn't properly charge any batteries that have a capacity rating of more than 1600 mAh. So what to do if you buy 1800+ mAh NiMH batteries and you own an early-generation timer-controlled NiMH-compatible charger? Simple. Buy a new charger or two.
That's exactly what I did today when I bought my 4-pack of the new 1850 mAh Energizer NiMH batteries; I bought a cheap Energizer AA/AAA/9V charger that has a 15-hour timer. Its 150 mA charging rate (for AA batteries) is lower than or equal to C/10 (for 1500 mAh or higher-capacity AA NiMH's), so you won't have to worry too much about overcharging batteries. I also have an 8-cell AA/AAA smart charger with Delta-slope termination and reverse-pulse charging -- but that charger can get fooled by damaged batteries, batteries that have been sitting unused for too ********* long, and brand-new batteries fresh out of the package (with those batteries, the charger operates for only 15 minutes and then shut off -- far short of a full charge). So, that rapid smart charger is for everyday charging -- but the cheap slow-charger is useful in tough circumstances. Thus, those two chargers (and possibly a continuously-operating trickle charger, as well) are all you need.
And my bad for saying that the Ray-O-Crap 1-hour charger had only timer control. In fact, it is a so-called "smart" charger. But too bad the major rechargeable battery manufacturers that distribute them through mass-market retailers offer only the 1-hour chargers with "smart" charging control (and I already knew that 1-hour chargers may actually deliver a charge current greater than C, which makes them much more likely than other chargers to cause overheating of the cells); all of their slower chargers feature only timer control. (Well, the Ray-O-Vac basic charger, for rechargeable alkalines and NiMH's, is the only cheap charger that has a so-called "smart" charge-termination control.)