The length of the battery life in a digital camera is impacted by many factors. One is the type of battery that comes with your camera. CRV3 and NiMH type batteries are among the longest lasting batteries. Check your camera to see what type of battery it takes. CRV3 batteries can last for up to 2000 exposures. You have to use the type of battery that your camera requires but you can buy additional 3rd party batteries that are frequently cheaper than those offered by the camera manufacturer.

There are some things you can do to increase battery life. The first is to always charge it fully and do not overcharge it. Over charging can damage some batteries and under charging can cause dead spots in the battery so that it will never fully charge again. Do not charge the battery until it full discharged. Turning off automatic functions like autofocus will also increase battery life. Using the view screen uses a lot of power so minimizing the use of the view screen will also increase battery life.

I am not sure why you would want to buy cameras in bulk. Having two batteries is enough for most users. If you are going out on along field expedition you might want to have three batteries. Look at deals for batteries on line at stores like Amazon and at stores like Best Buy.

Extending battery life
Don't open cameras and repeated. When the camera open, it USES a lot of electrical energy start all the necessary system. If you want to in a short time to take a lot of pictures, had better leave your camera, and not for the switching on and off. Each shot
Using the optical viewfinder, not liquid crystal display (LCD) : LCD screen, use a lot of power. If you use the viewfinder display LCD, not the picture frame, you will save power.
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