Buying batteries is more than just the purchase price (AKA when a bargain is actually a waste of good money). Weak battery performance can quickly dispel any notion of a bargain buy.
I have tried a few brands and found some 'bargain' NiMH batteries to be a complete waste of my hard-earned bucks. Performance is paramount if you are running an electrical appliance that places a higher demand on your batteries. Digital cameras demand performance, so there's not room for compromise if wish to remain a happy snapper.
I have found that the best rechargaeble batteries - no surprises here - are made in Japan (e.g. Energizer NiMH ). How do I rate performance? In simply terms, my performance is rating is based on the number of camera shots per battery charge. The best performer I have encountered so far is the Energiser brand rated at 2500 mAh. I only use AA batteries rated 2000-2500 mAh for my digital camera. A lower mAh battery is OK for low demand appliances like flashlights.
Choice magazine (Australia) surveyed some rechargeable batteries in Nov 2006 and they largely agree with my real-world findings.
While not equal in performance to the Energizer brand, other worthy contenders in the 'good-value NiMH' category included: Duracell, Kodak, DSE (made in China), and FujiFilm. Choice found that all of the above listed brands offered great bang for your buck (comparable to Energizer). They have an equal cost of ownership rating and were close in performance levels, according to Choice. I can only agree, as I have found DSE (Dick Smith Electronics) fantastic in my flashlight and other low-demand electrical appliances. DSE batteries seem to hold their charge for a longer period of time compared to other brands I've used. DSE brand NiMH batteries offer me reasonable performance, longevity of charge and good value for money.
So, the Energizer is the BEST performer and EQUAL BEST value for money battery. It wins outright in the bouncing-bunny performance category (sure you remember the bunny in the Duracell TV commerical).
So which brand should you buy? For high-demand appliances, like digital cameras, I would recommend the following (in order):
- Duracell; Kodak
- DSE; FujiFilm
Overnight chargers are best. Try to avoid 'rapid chargers'. They are hard on batteries, and will not competently fill the battery as much as a 60 to 100 minute charger. Charging batteries in 15 minutes also causes the batteries to heat up a lot and reduces the life of the battery. You will get a fuller charge and longer life from your batteries if you choose a charger that takes at least 60 minutes to recharge the cells.
WHEN ALKALINE BATTERIES ARE BETTER
Rechargeable batteries are not for every application. Alkaline batteries have a longer base shelf-life, so if your appliance is for occassional use, or if changing batteries is a pain, then alkaline may be the better option. For example, the disposable Energizer e2 is a high-capacity battery that will out-perform virtually any NiMH battery. For this reason, I use alkaline batteries for my bike light because it draws a low current and replacing the 4x AA batteries is a awkward operation (I have to unscrew the lid and delicately pull out a holder cartridge - something I don't want to be bothered with each week).
Rechargable batteries are not suitable for critical appliances like smoke detectors - they simply don't hold their charge for extended periods. Stick to alkaline batteries when endurance (long life) is paramount.
As a general rule, make sure you buy 'Made in Japan' rechargeable batteries. Except for the DSE brand, the 'Made in China/Thailand/Singapore' batteries do not consistently provide. As of 2009, Energizer batteries are 'Made in China', however as yet I have not noticed any deterioration in performance compared to the 'Made in Japan' Energizer batteries.
Charge NiMH batteries immediately before use (whenever possible). Don't store batteries in your cupboard for weeks then expect them to be fully charged when you use them - NiMH batteries lose their charge when stored (1-3% each day). Always carry spare batteries (you can NEVER have too many batteries on hold) for backup. Rather than leave rechargeable batteries in an appliance, take them out after each use, and put them back in the charger.
Typically NiMH batteries can be stored for between 3 and 5 years if stored at room temperature. It is recommended that NiMH batteries stored in a charged state. To attain full capacity after extended storage may require a few charge/discharge cycles to obtain maximum performance.