Ready to save some money on batteries?

1.5 AAA batteryLet’s say:

You have a TV remote or a small book light that uses three AAA batteries.  The TV remote no longer sends signals to the receiver and the book light does not turn on.  What do you do with the batteries?  Do you roll them around?  Do you rearrange the position of the batteries until the device works?  What if neither of those methods work?

Should you throw the batteries away and replace them with new ones?

MultimeterYou may not have to.  As I found out, you may have a “trouble-maker” battery.  But how would you know? Consider buying, or rather, investing in a multimeter.  Among the selections, a multimeter can be set to measure the voltage in a battery.  To my knowledge, a fully charged AAA battery typically has a quoted 1.5 Volt charge.

How to use the multimeter to measure a battery:

Measure the battery. Turn the dial to “20 Volts” of the Direct Current (DC) section of the multimeter.  This is because we’re measuring a 1.5V battery and 1.5V is within an appropriate range of 0V to 20V.  If you feel like exploring with a bit more accuracy, you can switch the dial to 2000mV (milli-Volts).  That is to say, the range is from 0V to 2V. Hold the positive and negative wands to the positive and negative nodes of the battery, respectively.  I labeled my red wand with a “+” so I would know which wand measured the positive end.  The example picture on the right shows that this particular battery has a near-full charge of 1.46V. Note:  I checked another battery with the same charge.  At this point I have two of the three batteries with the same charge.


Bad batteryI happened to find a battery with a negative charge!  Look how the positive and negative wands are consistent with the positive and negative nodes of the battery, just as they are in the previous picture.  If you rotate the battery so that the battery nodes are touching the opposite wands, the charge appears to be positive.  (Which would mean the fully charged battery would have a negative charge.)  In any case, this is our “trouble-maker” battery. From other previous sets of batteries I’ve tested when a device wasn’t working properly, I usually found just one battery that has a low or lower, positive, charge.  They too were “trouble-maker” batteries but they were still useful.

Simple Math

In the following examples below, notice what happens when I measure the two good batteries together on the left and when I measure a good battery and the bad battery together on the right.

Good Battery + Good Battery Good Battery + Bad Battery
1.46V + 1.46V = 2.92V 1.46V + (-0.16)V ≈ 1.29V

The bad battery, in this case, actually decreases the total charge!  I’m no expert, but I’m guessing some devices won’t operate if the total charge of a set of batteries is less than a certain amount.  Other simpler devices may run off of the raw charge of the batteries until they’re depleted.

Increase your efficiency and save money!

So how can we apply this information to our benefit?  Earlier, I briefly mentioned testing batteries that had a positive charge but not enough to power certain devices.  These batteries usually measured at 1.15V to 1.3V.  Whether or not you combine them with batteries with greater charges, they may not be enough to run a TV remote or a wireless mouse.  However, you can take these batteries to run simple devices like flashlights, book lights, simple gadgets, etc… Just… simple electronic devices that aren’t going to be a big deal when their power runs out.  At least, in this way, you can get the most out of a package of batteries. In addition, you may want to invest in a package or two of rechargeable batteries and a charger.  Some would argue that you spend more time recharging and rotating the batteries.  I say, if you have a few sets of rechargeable batteries then you will always be prepared to rotate dead batteries for fully charged batteries, and still have a packages of regular batteries ready incase of emergencies, and not have to spend more for an overabundant amount of regular batteries. As for our experiment here, we see we don’t have to throw away a whole set of batteries when they (at first) appear to be dead.  In this case, there was only one bad battery and so only one battery needed to be replaced rather than also wasting the two good batteries for three brand new batteries.  This means:

  • You will use regular batteries at a slower rate,
  • Extend the life of still useful batteries,
  • Spend less money in the long-run,
  • Save time, energy, and resources such as gas, used going to and from the store, and
  • It’s more environment friendly.

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