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What are the parts of a battery tester?

What are the parts of a battery tester?

Shop for Battery Testers

battery tester parts

Battery tester indicator

analogue dial indicator battery tester


Analogue battery testers use a needle dial to indicate the test battery’s remaining power. This is usually on a three part, colour-coordinated scale. Green is good, yellow is low and red indicates whether the battery needs to be replaced or recharged. Typical household batteries will have voltages between 1.5 and 9, which will be accommodated by battery testers.

battery tester scale Some battery testers will have several smaller scales underneath the main one. These are usually colour coordinated in the same as the larger scale, but will be slightly shorter. These scales are for batteries which are different or have different voltages (such as the rechargeable or coin batteries). The product spec or information on the tester itself will indicate which scale you should read from.
digital battery tester bar indicator


Digital battery testers use an LCD screen which shows the remaining battery power in the form of bars. There will be a scale along the outside of the screen, much like that on the analogue dial, indicating whether the battery is good, weak, or needs recharging/replacing. There may also be numbers to indicate the voltage levels.

Battery tester battery slots

battery slots on tester A battery slot is where the battery is placed for checking. There are different types and sizes of battery, so there are different types of slots for these on battery testers. Some battery testers have adjustable spaces, to accommodate a range of battery sizes.
batteries The types and sizes of battery that a battery tester can test, varies, so you should check before you purchase to ensure your battery needs are met. The three main types of battery are cylindrical, square and coin so there are usually specific slots available for these, on testers.
cylindrical slots on battery testers

Slots for cylindrical batteries

There are three different methods with which battery testers can accommodate cylindrical batteries:

  • Adjustable arms
  • Sliding adjustment bar
  • Individual slots
analogue battery testers moveable arm and sliding bar

Adjustable arms and sliding adjustment bars

Most commonly found on the analogue battery testers, the adjustable arms and bars work in a very similar way. There is a fixed terminal at one point on the device, where the battery is placed, and a moveable terminal (on either a bar or an arm), which moves to sit atop the battery. This allows the device to test cylindrical batteries of multiple sizes.

This could be a potential problem for very large batteries, as the arm/ bar may not extend enough; however, as battery testers are designed for common batteries, this should not be an issue.

digital battery tester cylindrical slots

Individual slots

The individual slots found primarily on digital battery testers are designed to accommodate cylindrical batteries of different sizes. These slots are very similar to the ones you find in remote controls, for example.

square battery slot on battery tester

Slots for square batteries

To test these batteries, the clasps are placed on two square plates, usually found on one side of the battery tester on an analogue battery tester and two round plates on the digital battery tester.

coin battery slots on battery testers

Slots for coin batteries

In analogue battery testers that have the capacity to test coin batteries, the batteries fit in the same way as cylindrical batteries, with a sliding bar or moveable arm. The coin batteries actually fit in the same slot as the cylindrical batteries, as the bars and arms can be adjusted to the smaller size. These are often the batteries which require the use of the smaller scale on the analogue dial.

On some digital battery testers, there are individual slots for coin batteries of different sizes.

other battery slits on a digital battery tester

Other slots

On some digital battery testers, there are extra slots for other types of battery. These are usually batteries used in cameras, like the 2CR5 and CR-P2 batteries. Typically, they will only need to contact the tester at one end, and therefore are held against shallow, individual slots with your hand.

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