Best deals on camera batteries.(Up front: news/trends/advice)

The digital cameras covered on page 12 run the gamut of size, shape, and price. But they share one trait--a thirst for power that makes the choice of battery critical. Our tests point to rechargeable batteries as the clear, cost-effective choice, even if the prices give you sticker shock.

RECHARGEABLES: THE BEST CHOICE

Our tests included five brands of rechargeable nickel-metal hydride (NiMH) AAs with their chargers. They come in three basic power levels: 1,800, 2,100, and 2,200 millliamp-hours, or mAh. The higher the number, the longer the batteries can power a digital camera. But our tests didn't show any major differences in capacity within a power level. In other words, all the batteries worked well.

The rechargeables carry a high initial cost (a set of four batteries plus charger ranges from $30 to $50), but their long life makes them by far the most economical to use.

Here's the math:

Suppose a pair of alkaline batteries costs $2.20 and delivers 100 photos. The cost for the same number of pictures from disposable lithium cells will be about $1.40, we estimate. But because nickel-metal hydrides last through hundreds of recharging cycles, their cost for 100 photos is only about 1.5 cents.

The tested chargers work equally well. Three will quick-charge four AA cells in about an hour. (The PowerEx takes a bit longer, and the Kodak will quick-charge only two cells in an hour and four in about two hours.) Two chargers offer a trickle charge that allows you to store batteries in the charger without damaging them. Some accept 240-volt input from foreign outlets, or 12-volt input for use in a car.