This video tutorial is geared toward people who want to take a deep dive into better understanding how battery voltage can impact your paper circuits. In it, you’ll learn how to measure the voltage in your coin cell batteries using a multimeter. Additionally, we’ll explore some of the nuances of how voltage works within a paper circuit.
By watching a series of voltage experiments in real time, you’ll see how batteries with different voltages behave within a series of test circuits. This can be a useful strategy for understanding a battery’s potential, even in cases when a multimeter may not be available.
In addition to learning how to determine the potential for freshness in a coin cell battery, you’ll see a technique for using a resistor to test a battery’s voltage under a load. Knowing how to test battery voltage under a resistive load will help you to better understand why a battery that you believed to be fresh may not be working as expected.
Tips, Tricks & Call-outs
Under normal circumstances, a fresh coin cell battery will measure over 3.2V, while a battery that has fallen to 2.7V or under is considered dead. It is, however, possible for a battery that initially measures at 3.2V to actually be a bad battery. This can happen if the battery is old or has been exposed to extreme conditions such heat or humidity. One way to find out whether your battery is healthy is by testing the battery under a resistive load. If the battery tested under a load measures below 2.8V, it should be considered dead.
Useful Tool & Supplies
- a multimeter (autoranging or manual)
- Circuit Sticker LEDs
- Copper or Conductive Fabric Tape
- Conductive Fabric Tape Patches
- a 470 ohm resistor
- electrical or washi tape
- wire strippers
- a male to male jumper wire
- a pair of alligator clips
- printed copies of Voltage Experiment Charts and Test Circuits (see below)
The following timestamps are linked to different parts of the video, should you wish to jump to a specific part.
00:00 Start
00:14 Introduction
01:14 Features of an Autoranging Multimeter
02:26 Features of a Manual Digital Multimeter
03:54 Measuring Voltage
In this section, we’ll measure the voltage of five different coin cell batteries taken straight from their protective packaging.
07:26 Testing Different Batteries
In this section, a battery taken straight from its packaging tests over 3.2V, yet it behaves like it is dead, prompting us to conduct a new experiment.
12:21 Discovering a Dud
In this section, you’ll learn how to use a resistor and a multimeter to get a more accurate read of a battery’s true potential.
13:48 How to Test Battery Voltage Under Load
In this section, you’ll review some strategies try when your circuit is not working properly, commonly the result of a weak battery.
19:31 Strategies When You Have a Weak Battery
21:33 Closing