I've used these in my wife's Nikon Coolpix for over 3 years now. I know we've charged them more than a dozen times. Assuming a pack of 4 AA disposable batteries runs about $5 average, that's over $60.
Based on this usage pattern, it looks like we got a little over 3 years out of the first set of 4. Although not quite up to the 5 years you'd expect out of a car or UPS battery (which are lead acid and a different technology) these Eneloop batteries definitely have a slower self-discharge rate than any of the NiCd or NiMh batteries we tried at first.
From the start 3 years ago, I have been using the Powerex WizardOne aa/aaa NiMH Battery Charger-Analyzer which I use to monitor the capacity of these batteries. Brand new, they typically report between 1800-1900mAh and when they start falling below 1600mAh, I'll put them through a conditioning cycle on the Powerex MH-C9000 WizardOne Charger-Analyzer. That always brings them back up to the 1800-1900mAh range except recently (after having the 1st set for over 3 years) where it stayed around 1500mAh after conditioning.
I'm sure I could have kept using the decreased capacity batteries longer but getting 3+ years out of the 1st set was well worth the price to just by this new set. Since the Nikon Coolpix only uses 2x AA batteries, my wife keeps the 2nd set of 2x AA Eneloop batteries in the camera case as a backup. As a testament to the slow self-discharge rate of the Eneloop, those backup batteries may sit in the camera case for over 2 months since being charged, but when she needs them and puts them in the camera, they still show full charge and she can take pictures for at least a month. When we used NiMh batteries in the same manner, the backup set would already be 1/2 dead in 2 months.
| Item Package Dimensions L x W x H | 2.36 x 2.2 x 0.71 inches |
|---|---|
| Package Weight | 0.26 Pounds |
| Item Dimensions LxWxH | 0.79 x 0.79 x 0.79 inches |
| Item Weight | 3.84 ounces |
| Brand Name | SANYO |
| Model Name | FBA_HR-3UTG-4BP |
| Number of Items | 4 |
| Manufacturer | Sanyo |
| Part Number | FBA_HR-3UTG-4BP |
| Model Year | 2009 |
