# Battery Testing

## Objective

To test various types of batteries to determine which last the longest.

Procedure: Easy

Concept: Easy

## Concept

Have you ever noticed how the price of Duracell or Energizer batteries is significantly more than generic brands? Does this price difference actually make a difference? Obviously, the goal here is to save money. If all batteries are the same and will last the same length of time then there is no reason to spend extra on name brands.

## Hypothesis

What do you think? Is Energizer the best? Or maybe Duracell?

## Materials

• Various brands of AA batteries
• Multimeter (optional)
• Resistors (optional)
• LEDs (optimal)
• Wire (optional)
• Tape
• Timer
• CD Player
• Flashlight

## Procedure

1. The first step will be constructing an apparatus that can test the batteries. Depending on how involved you would like to make the project, you can either use the CD player or create a small resistive load to drain the batteries.
2. If you choose to use the CD player, find a CD, set it to repeat and run the player until the batteries die. Similarly, you can use a flashlight to run the batteries down. Record the time it takes and repeat with each brand of battery. Make sure to run multiple trials with each brand.
3. If you are more familiar with electronics, you may want to try creating your own circuit to test the batteries. By simply wiring an LED in series with a resistive load, you will be able to see the light grow dimmer as the battery runs down. Record the time it takes for the light to go out.
4. After all the data has been recorded, average the times over each brand of battery. Graph the results and compare.

## Review of Literature

Different batteries perform better under different conditions. Many companies create datasheets of their products. By looking at these datasheets and combining them with Ohm's law, it is possible to calculate what the expected battery life should be depending on the resistive load.

## Results

You can plot the results of your findings in a graph or chart, using the variables battery name and time (that the battery lasts). If you want to make a graph in Excel, look at our Graphing in Excel page.

## Conclusions

This section is for you to fill in. Your discussion should focus on explaining any trends you found in your data. Remember, even if you cannot find any trends, that result is still significant. Also, try to think of a way to compare the price/value of each brand of battery to determine which gives the best deal. There are many extensions to this project. For example, what are the differences in performance between the various types of batteries (i.e. AA, AAA, C, D, etc.)? Do lithium batteries last longer than alkalines? Do not limit yourself to just this guide. Try to come up with your own additions.