Finding the Right Camera Batteries
Camera batteries power the electrical components of digital cameras, including their LCD displays and electronic viewfinders. Since cameras are high-drain devices, you'll need to replace batteries regularly. Disposable batteries can be very expensive, so if you shoot often, it's best to opt for rechargeable batteries.
Types of Camera Batteries
There are four types of digital camera batteries: cylindrical, button, lithium pack, and prismatic. Cylindrical cells include regular AA and AAA batteries used for budget compact and superzoom cameras. While alkaline cells are common, lithium ones are lighter, keep a charge for longer, and have better resistance to extreme temperatures. Note that rechargeable alkaline and lithium cells require different portable battery chargers. Button cells are coin-sized batteries used by vintage 35mm film cameras. Most of them are non-rechargeable.
While all lithium packs employ the same cell chemistry, camera manufacturers offer them as proprietary batteries for their product lineups. These come in different shapes and sizes and have higher voltage outputs than cylindrical cells. Prismatic cells are similar to lithium packs but thinner, to allow for slimmer camera designs. To prevent swelling, manufacturers encase them in aluminum and steel. As with some cylindrical and all lithium packs, you'll need to find the right digital camera battery chargers for these cells.
What Does mAh Mean?
This refers to milliampere-hour or one-thousandth of an ampere-hour. This is a measure of power capacity, as it specifies the amount of electrical energy the cell can store. In technical terms, mAh describes the amount of current (amperes) that can flow out of the cell over a period. Therefore, a 120mAh unit can supply 120 milliamps of current for 1 hour, 12 milliamps for 10 hours, or 1 milliamp for 120 hours. The higher the mAh rating, the higher the capacity of a battery, and the bigger it is.
Can You Overcharge a Rechargeable Battery?
Yes. Overcharging occurs when you leave the cell in its charger after it's fully charged. Overcharging can reduce your battery's lifespan. To avoid inadvertently overcharging cells, get a smart charger. Smart chargers check the status of rechargeable cells and stop charging them when they reach full capacity. They then switch to trickle charging to keep them at full capacity. This is especially important when shopping for universal batteries and chargers from third parties for your camera.
Benefits of Battery Grips
Battery grips complement your main battery and significantly extend shooting times. Some battery grips take cylindrical cells while others have slots for proprietary lithium packs. In addition to powering cameras, grips make vertical shooting easier. Some grips offer users additional shutter release and control buttons, while others bump up shooting speed in burst mode.