Today, I'd like to take a look at three different types of AAA size battery - non-rechargeable, NiMH rechargeable, and Sanyo Eneloop NiMH rechargeable - to see how Eneloop stands out and why it is the bargain among the three.
- 20 Duracell non-rechargeable AAA $7 shipped ($0.35/cell)
- 4 Duracell Rechargeable AAA $7.97 shipped ($1.99/cell)
- 4 Sanyo Eneloop Rechargeable AAA $9 shipped ($2.25/cell)
Using regular NiHM rechargeable might lower your cost, by a lot, especially after 5 times of recharges. However, the biggest obstacle you may have experienced using regular rechargeable is its high self-discharge. The experience of installing a rechargeable battery that you charged up a month ago may not be too pleasant because of it's likely to run low pretty soon. Why? Because regular NiHM battery self-discharges over time. But how fast does it self-discharge? According to this excellent review, the charge loss is about 83.8% after six months. In other words, a Duracell NiHM battery has a mere 16.2% charge retention rate six months after it sits on the shelf. No wonder many users are disappointed and dislike rechargeable batteries and switch back to regular batteries after trying NiHM rechargeables.
Before you totally give up on rechargeable batteries, you must try Sanyo Eneloop. Eneloop is only 15% more expensive than other types of NiHM rechargeable batteries (e.g. Duracell, Energizer, Gold Peak). But there's a big difference in charge retention rate as Eneloop is claimed by SANYO to keep 85% of their charge after sitting on a shelf for one year. In the same 3rd party review I mentioned earlier, Eneloop has charge loss of only 29.8% (vs. 83.8% of other NiMH) about after six months sitting on a shelf. Even after one year, the Eneloops would still have half their capacity, whereas a regular NiMH battery would be virtually dead.
I conclude that SANYO Eneloop cells are worth every penny. The cost benefit exceeds non-rechargeable batteries after you reuse a Eneloop 6 times or more. Besides, SANYO Eneloop can be charged in any normal slow or fast charger designed for regular NiMH cells.
by Charles Gwa