Well, after years and years of using cheap NiCd and NiCd/NiMH chargers (all of which are either "overnight" chargers that have no charging control whatsoever or are "quick" chargers and charger/conditioners that not only are timer-controlled but also tended to overcharge batteries to varying degrees of extent), today I decided to bite the bullet and spend $34.99US plus tax at RadioShack for a "smart" but rapid charger that charges two to eight AA or AAA batteries in less than three hours (but with no overcharging! WOO-HOO!!
) or one or two "9V" batteries in about eight hours. The RadioShack catalog number in #23-422. (BTW, that charger's smart-charging feature works only for AA and AAA batteries; with "9V" batteries, only timer charging control is available.)
I proceeded to charge a (much-used) pair of RadioShack #23-149 850mAh NiCd AA batteries - they got "fully charged" in about half an hour - and the batteries NEVER even became warm! WOW!!!
(Too good to be true... It turned out that those NiCd batteries were somehow damaged by improper charging.
And a follow-up test on a set of Energizer 1200mAh NiMH AA batteries indicated that they charged in under two hours - and they got fairly hot to the touch. They got hot even charged with the Eveready charger designed specifically for those batteries, too.)
I am currently running that pair of batteries in my Sony D-EJ721 PCDP to determine if they last anywhere near as long between charges as the same batteries that I had charged with my previous chargers. If they do, then my judgment of the types of battery chargers will be ranked in order from best to worst:Best:
"Smart" chargers (regardless of charging speed)Tolerable:
"Overnight" chargers with timer controlWorst:
"Quick", "Fast" or "Rapid" chargers with timer control
Hope this guide helps.