How a Battery Tester Works

Getting more life out of batteries

Battery testers are useful tools in determining whether or not a battery has any charge left. There are two main types of battery testers: those that use conductive ink, and electronic battery testers.

Conductive Ink Battery Testers

Some battery packages come with a test strip that can be used to determine the overall life left in a battery. The ink within the strip is conductive, which means that it heats up when the current from the battery is held to it. A higher temperature with this type of battery tester will indicate how strong the charge is.

Electronic Battery Testers

Electronic battery testers work by actually measuring the amount of charge left in the battery. They come with two leads, a black and a red. The red lead is placed on the positive side of the battery and the black is placed on the negative. The meter will display a reading once the leads are connected.

Inaccurate Readings

Battery testers are not made for testing lithium batteries, and will not display an accurate reading when used on a battery of that type. This is due to the fact that lithium batteries do not discharge evenly, in the manner of an alkaline battery.

References

• Battery Web: Battery Tester FAQ