Power Tool

Batteries for Cordless Tools

It cannot be denied that electricity which comes from your socket definitely drives your corded tools to full power, enabling them to perform their functions more efficiently. But corded tools can also bring some inconveniences and accidents. If you don’t wish to get stumbled by a tangled cord, or experience electrical hazards with a damaged cord, then cordless tools should be a good alternative. If you love using power tools but are worrying about energy bills, cordless tools are an economical solution.


Most people who are looking for cordless tools take their battery life into big consideration. After all, batteries are the key to a cordless tool’s useful life.

The following are the two common types of batteries used for cordless tools:

  • Nickel cadmium or NiCad – NiCad batteries are currently the most popular as they typically re-charge quickly and have a constant discharging rate. However, used NiCad batteries end up as hazardous wastes.
  • Nickel metal hydride or NIMH – NIMH batteries are some of the newer batteries to come out on the market. They are also more expensive. But when handled correctly, they can prove to be longer-lasting compared to NiCad batteries, at least when used in smaller tools. Compared to used NiCad batteries, used NIMH batteries are not considered as hazardous wastes. However, NIMH batteries cannot handle the high rate of charges and discharges (usually over 1.5 to 2 amps) that NiCad batteries are capable of.

Other things to consider are the voltage and the weight of the batteries. Naturally, people want to get more power out of their cordless tools, so they tend to choose the batteries’ voltage over weight.

An individual battery typically contains 1.2 volts. Each power tool requires a certain amount of voltage. For instance, a particular power tool requires 8 batteries to produce 9.6 volts, while another tool needs 15 batteries to produce 18 volts, and so on.

However, the more batteries you load into your power tool, the heavier the power tool feels, and that may be more difficult for you to work on it. Using a heavy power tool for longer periods of time will certainly cause hand fatigue.

That’s why it’s important to compare the batteries’ voltage and weight carefully to get a power tool that will be able to do its job and still feels handy and convenient to use.

The battery’s amp hours (Ah) rating is an indication on how long the charging will last. Most NiCad and NIMH batteries have a 2 Ah rating, but 3 Ah NIMH batteries will come out soon. Batteries with higher Ah do not normally weigh more than 2 Ah counterparts, so it is best to choose batteries with a similar voltage but with a higher Ah rating.

Most current battery chargers on the market feature an indication which lets you know that the batteries are fully charged. Still, you should not forget to check your power tool (that’s still charging) from time to time to make sure that it will not be overcharged. The standard charging time is one hour, but some chargers can load batteries as short as 15 minutes, while others have a three-to-four-hour charging time. If you use a power tool only occasionally, the longer charging time won’t be a big issue.