The Differences in Batteries for Digital Cameras

Picking a battery for a camera used to be easy. They were either zinc-carbon cylinders in easy-to-remember sizes such as AAA, AA, A, C, or D, or flat pancake cells using mercury. Now, there are a multitude of sizes and technologies specific to the digital camera being used. Many of these batteries can't be procured from a local store. They must be obtained from a camera store, online retailer or the digital camera manufacturer.

Technology

There are many types of batteries used in digital cameras. These include the old zinc-carbon cells, alkaline cells, rechargeable alkaline, nickel cadmium (NiCad), nickel metal hydride (NiMH), lithium, and lithium ion (Li-ion). The zinc-carbon, alkaline and rechargeable alkaline cells aren't used in many cameras now because of their low energy capacities.

Size

The size of the batteries depends on the technology of the cell and the camera that they will be used in. The zinc-carbon, alkaline, rechargeable alkaline, NiCad, NiMH batteries used in cameras are typically AA size cells. The lithium cells can be found in a AA size or in other sizes such as the CR-123 format, which is slightly larger in diameter and shorter than a AA cell. Li-ion cells are available in many sizes and shapes and are camera-manufacturer specific.

Capacity

The capacity of a battery is a function of its size, the voltage output and the amount of current it can deliver before it is discharged. The lowest capacity cells are the zinc-carbon, alkaline and rechargeable alkaline. The NiCad rechargeable cells have a reasonable storage capacity. The NiMH rechargeable cells can store about 50 percent more than an equivalent size NiCad. An equivalent volume Li-ion has about 175 percent of the NiMH cell capacity. All of the types mentioned exhibit a relatively flat voltage output until they are nearly discharged at which point the voltage starts dropping.

Discharge Rate

The discharge rate represents how fast the current in the battery is used. Except for the fraction of a second after the shutter release is pressed, a camera uses very little current. Any battery, if it is discharged too fast, will overheat and explode.

Charger

It is highly recommended that a charger designed for the battery technology is used. Charging a battery too fast can generate heat, lower the efficiency of the battery and reduce its capacity. In particular, charging a Li-ion battery too fast can cause the battery to catch fire and explode.

References

• Consumer Search Batteries Full Story
• Digital Camera HQ, Batteries for Digital Cameras
• Pure Energy Learning Center, Battery Types: Which Batteries to Use?

Resources

• Nikon camera and battery information
• Canon camera and battery information
• Sony camera and battery information