Well this is a bit of an unexpected surprise: Apple has jumped into the business of rechargeable batteries, releasing their own Apple Battery Charger. The six battery and charger system is perfect Apple users with wireless peripherals that need regular battery replacement, but these batteries are rated for a 10 year life, giving them an impressive longevity.
The Apple Battery Charger has also been engineered with an intelligent power management system which tapers back power once the batteries have reached full charge; just enough to keep them topped off with power, but with a reduction which should limit vampire energy use. The charger can only charge up 1-2 batteries (we would have preferred 4 and AAA size option), but is also compatible with AA NiMH batteries from other companies and even after a year of storage, charged batteries still retain 80% of their original charge.
Available now for $29.00.
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I've been loving the eneloop batteries for a while now. I'm sure these will be equally as good. But, for the same price I can have 12 eneloops and 4xcharger. At this point the only selling point would be convenience/immediacy since I'm not aware of a local store that I can walk into and buy the sanyo eneloops. If any one knows of one let me know.
I suspect that is a ten year lifetime when used in a wireless keyboard/mouse/trackpad. Probably much closer to average when used in other devices.
I use the Energizer rechargables and they seem to work well. For $29.00 does that include the batteries or just the charger?