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Battery Health Testers

27 November, 2023

Battery Health Tester

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Battery health testers are devices designed to assess the condition and performance of batteries. They are devices that aren’t well known, but they can really help you with your batteries, especially if you have batteries of different sizes

What are Battery Health Testers?

Battery testers are small appliances that are commonly used to determine the remaining capacity, voltage and overall health of a battery.  They come in different sizes, depending on the different types of battery they can test, and they may vary in complexity and features. Their basic principle though is to measure specific parameters that indicate the state of the battery. This can be helpful in deciding whether a battery is worth keeping, or is better to be recycled, how well it performs and if it is safe to keep it.

So how do Battery Health Testers work?

In general, battery health testers measure tseveral different characteristics of a battery and provide the respective readings that show the battery’s condition. They usually have probes or connectors that are attached to the battery terminals to perform the tests.

The first characteristic battery health testers measure is voltage. This is most fundamental aspect of a battery because it shows the electrical potential difference between the positive and negative terminals of the battery. The closer this is to the nominal voltage of the battery, the better condition the battery is in.

The second thing measured is load. The process is called Load Testing and it involves applying a controlled load to the battery while monitoring its response. This helps determine the battery’s ability to deliver power under real-world conditions. During load testing, the battery tester may simulate the electrical load that a device or system would impose on the battery. The tester measures how well the battery maintains its voltage and how quickly it recovers after the load is removed.

Another characteristic measured is the battery’s Capacity. Battery testers often estimate the remaining capacity of a battery. Capacity is the amount of energy a battery can store and deliver. Battery testers use various methods to assess capacity, such as discharging the battery at a controlled rate and measuring the time it takes to deplete. The result is then compared with the nominal capacity of the battery as stated by the manufacturer, helping you decide whether a battery is in good condition or not.

Some advanced battery testers also measure the battery’s Internal Resistance. Internal resistance is a critical factor affecting a battery’s performance. If too high, internal resistance can lead to voltage drops and reduced power delivery. This is measured by analyzing the battery’s response to an AC (alternating current) signal.

Where do I see the results of a Battery Health Tester test?

The results of the battery test are typically displayed either on a screen or through LED indicators. The level of information depends on the model but in general you get indications about voltage readings, capacity estimates and, in advanced models, even recommendations about the battery’s health.

Which battery health tester should I buy?

We have listed the best ones you can find in order of simplicity, from simplest to the most complex. As expected, the more tests a tester can perform, the higher its price. A battery tester that provides a voltage indicator can be enough for home use. Look for one that supports the most sizes possible so that you can use it with all the batteries you own. The only thing you need to be aware of is that you must buy a battery tester that is compatible with the chemistry of the batteries you own. In the list below, we have included this information to make it easier for you to choose.

Here are some great battey health testers we recommend:



  • Checks AA, AAA, C, D, 1.5V, 9V and button type miniature cells
  • Has no internal battery, it is powered by the battery being tested.
  • LCD Screen

Battery Tester Checker

  • Checks C, AA, AAA, D, N, 9V 6F22, and 1.5V button cell batteries
  • Has no internal battery, it is powered by the battery being tested.
  • Small size, very portable
  • LCD Screen with visual indication only (no digits)

Dlyfull LCD

  • Checks AA AAA C D 9V CR2032 CR123A CR2 CRV3 2CR5 CRP2 1.5V/3V Button Cell Batteries
  • Requires 1 AAA battery (included)
  • LCD Screen with visual indication only (no digits)


  • Very easy to use
  • Only for Li-ion, NiMH and Alkaline batteries
  • Easily test batteries with the included probe
  • Includes LEDs as indicators of battery health


  • Very easy to use
  • The most comprehensive battery health tester you can buy.
  • Check NiMH, Li-Ion, alkaline, lithium, coin cell, button type and more: 3.6v Li-Ion rechargeable [RCR123A, 18500, 17650, 18650]; 1.5v button cell [S76, A76, A625, A640, LR44, 357, 303]; 1.2v NiMH/NiCd rechargeable [AA, AAA, C, D]; 1.5v lithium [AA L91, AAA L92]; 3v lithium coin [CR1216, CR1220, CR1232, CR1612, CR1616, CR1620, CR1632, CR2016, CR2025, CR2320, CR2032, CR2430, CR2450, 58L, 1/3N]; 6v ’28’ series [28A, S28, 28L, 544, 4LR44]; 3v lithium cylindrical [CR123, CR2]; 1.5v alkaline [AA, AAA, C, D, N]; 12v alkaline [A23]; 9v alkaline & carbon zinc
  • Comes with handy probe
  • Includes LED indicators of battery health