More and more tools in everyday use for home repair and gardening are cordless and are powered by rechargeable batteries. Unfortunately, many users of cordless tools don’t take proper care of them, so batteries wear out prematurely and don’t respond to recharging.
Replacing rechargeable batteries can be expensive. A new battery pack for a drill, for example, can cost $50 or more.
Cordless tools can contain any of several types of batteries, including nickel-cadmium, nickel-metal-hydride, and lithium ion. Incidentally, rechargeable batteries contain hazardous chemicals that can pollute soil and groundwater, and they should not be disposed of in the trash. (Alkaline batteries, which are not rechargeable can be put in the trash). Places that will accept rechargeable batteries for recycling can be located by calling 800-822-8837. Dial the number, enter your postal ZIP code and you will be given the name of a center near you. Most rechargeable tools come with owner’s manuals that specify the correct recharging time. Some tools can be charged in an hour; others require four hours or more . I recommend placing a label on the charger or on the tool itself stating the charging time. This can help avoid overcharging, which can damage the batteries in some tools, and also keep the device at peak operating power. Always unplug a charger after it has charged a tool or battery pack.
Some chargers have tiny indicator lights to let users know when a full charge is reached. If you have a charger with such signals, be sure to check the owner’s manual to understand what the signals mean. Also, make sure a battery pack is firmly seated in the charger so that good contact is made.
In general, a tool can be recharged as soon as it shows signs of losing power.
If a battery pack becomes hot from extended use, let it cool for about 30 minutes before placing it in a charger. Some chargers even have built-in sensors that delay charging until the battery pack cools.
When possible, buy tools that include spare battery packs so that one set of batteries can be kept fully charged and ready for use while the other is being used.
Excessive heat and cold are probably the chief destroyers of rechargeable batteries. Don’t leave a cordless tool in hot sunlight for long periods, and don’t store it over the winter in an unheated garage or shed. Keeping cordless tools at room temperature is one of the best ways of extending their lives. Batteries should also be charged at room temperature rather than in hot or cold locations.
The life span of rechargeable batteries varies widely. I have one cordless drill that still has excellent power after about 10 years of use. Other cordless tools I have owned developed power problems after only a few years. In my experience, the average useful life-span of rechargeable batteries is four or five years. High-powered replacement battery packs are the most expensive, so one way to save money is to keep your cordless tools within a modest power range. Cordless-tool power is rated in volts, with some tools at 24 volts or more. (The greater the volts, the greater the power.) Cordless drills–the most popular cordless tools–with 12 volts of power are adequate for virtually any job a do-it-yourselfer is likely to encounter, and are lighter and easier to handle than more powerful tools.
