Battery Voltage

[Steveo31]

What exactly does more or less voltage, in say, a flash mean to me? For the 550EX, 1.5V are what it has written on it, but I use 1.2V rechargable NiMh's with no probs.

[robertwgross]

If you check the 550EX manual, page 12, it tells you that you can use just about anything in the AA-size battery.

The voltage rating on a battery is the rated voltage, and that may or may not be close to the actual terminal voltage (which is commonly measured without any load). Some devices will be very picky about the voltage of the batteries, but the 550EX is not one of them. You can use anything from about 1.2 up to about 1.6 volts. However, the higher the voltage, the faster the flash recycling will be.

In the long run, NiMH batteries are fairly practical for this use. I also use alkalines and sometimes lithium primary batteries, just depending on what the situation is. Lithium primary batteries are great in cold weather, but they are very pricey and non-rechargeable.

NiMH aren't the best in the world for each category of battery performance, but they are a good all-round battery for many.

---Bob Gross---