Sanyo Eneloop batteries to be exact. We all know how expensive batteries are, and we also know just about every item a child has requires some mass quantity of power to work. In addition to that, we have learned to understand these batteries seem to last only a matter of days on a heavily used device. Over the years I have dabbled with rechargeable batteries, only to find they to wear down quicker than I would have liked, especially given their premium price over standard batteries. When I say “wear down” I don’t mean the hours of use between a recharge. I am speaking about the lack of shelf life while the batteries aren’t being used and waiting to be called into action. I prefer to keep a stock of batteries available for those moments when duty calls, and I hear “DADDY! Our batteries are dead!”. I have experienced the agony of defeat when I hear those words and I have not one battery laying around to assist in resuscitating a broken magic wand, or some other “important” item.
The Sanyo Eneloop solved all of these problems for me, and I believe is saving me significant amounts of money. While the product is just a type of Low Self-Discharge Nickel-Metal Hydride Batteries (LSD-NiMH) (Wikipedia Link), I cant say enough great things about them. You can find these at your local Costco / Sam’s, or online from several sources. I made my purchases from Amazon.com. I have made several purchases of the AA and AAA packages, and have not had one regret. The batteries provide excellent “use” time, and also maintain their charge while on the shelf. Don’t let the upfront expense scare you away. Obviously you will need to perform your own math, but at the rate I was using batteries, the Eneloop setup has paid for itself many times over in just a few short months.
In addition to the battery themselves, I also purchased the La Crosse BC-700 “smart” charger, which allows you to charge the batteries at different rates, test the batteries, and provide over-charge protection. I prefer slow charging over quick charge simply to save the wear and tear a quick charge introduces to the battery. I saw this charger as an investment to prolong the life of the battery. The additional charger upgrade might not be for everyone, but given my projected use, I felt it was worth the investment.
So far, so good. We no longer buy AA, AAA, C, or D batteries unless they are part of the Eneloop (LSD-NiMH) family.