More about GPS battery

After you select the type of batteries you’re going to use, you should be aware of some other issues when it comes to powering GPS receivers:

• Battery life gauges: In the GPS receiver’s setup information page, you can specify what type of battery you’re using, such as alkaline or NiMH. The battery type setting helps the GPS receiver make an accurate guess how long the battery will last. Remember that different battery types have different discharge rates. All GPS receivers also have an onscreen battery gauge that shows you how fully charged the batteries are. If you set the wrong type, the worst that will happen is that the gauge won’t be accurate. See how to extend battery life with some GPS receiver models in the sidebar, “Battery saver mode.” Always check the battery level of your GPS receiver before you head out on a trip and also remember to carry spare batteries. One way to tell which batteries are new or charged is to put a rubber band around the good ones. By feeling around in your pack or pocket, you can instantly tell which ones are fresh. Note: Rechargeable batteries discharge faster than alkaline batteries when they’re not in use, so if you haven’t used your GPS unit in a couple of months, don’t be surprised if those rechargeable batteries are dead or don’t have much life left in them.
• Cigarette lighter adapters: If you’re primarily using your GPS receiver in a car or truck, you can save on battery costs by powering the GPS receiver with a cigarette lighter adapter. These handy devices run a GPS receiver from your car’s electrical system. You can buy a generic version or one made for your model (sold by that GPS receiver manufacturer). Depending on the model, adapters cost between $20–$40, with the generic versions a bit cheaper than the manufacturer models. Cigarette lighter power adapters have straight or coiled cables. Although coiled cables are tidier, if your cigarette lighter isn’t close to the dashboard, a coiled cable can pull your GPS receiver off the dashboard if it’s not securely mounted. Adapters with straight cables don’t have this problem; you can tidy up any slack in the cable with a plastic zip tie.