Cellphone dead? AA batteries to the rescue!

Cellphone-toters dread the sound: a hand-held device chirping its complaint, often far from home base, about needing to be recharged.

Now on the market: a lipstick-size brass canister that holds one AA battery and offers reserve power. Run a short adaptor from the tip of a Turbo Charge to your phone, and a blue light indicates that a charge is flowing. You're back in business long enough to get to a plug – the device's maker, Voxred International, claims "up to 40 hours" of standby time or two hours of talk, and touts patent-pending technology that protects devices' batteries from damage. It is designed to work with PDAs as well.

We tested Turbo Charge – about $20 at stores including Best Buy, Sports Authority, and Office Depot, $5 more with a bundle of adaptors and a carrying case – on a Samsung SCH-A630 phone. Getting the right adaptor took some doing. In a service the firm says it extends to all customers, it sent us an adaptor not in the original bundle, and then walked us through the extra wiggling that first use required.

When the depleted Samsung started scolding one night around 8, we attached the device. The phone quieted and began indicating a charge. We made a 20-minute call. Then we left the phone on and plugged into the charger. By 3 a.m. it was indicating low battery again; but we were using an alkaline AA rather than lithium. Verdict: a sensible spare with some novelty appeal.