The batteries in most consumer electronics produce 1.5 volts each.
Different products use different numbers of batteries to achieve different voltage requirements. For example, a TV remote might be designed to run on 3 volts, so two 1.5 volt batteries will provide the necessary voltage when connected in series.
Larger devices, such as radios with large speakers or large kid’s toys, typically have larger batteries, like C and D cells. Smaller devices often use AA and AAA batteries, allowing the devices themselves to be smaller. All of these batteries output 1.5 volts, but the larger batteries have much higher capacities, meaning they last longer. D batteries have four times the capacity as AA’s.
There are many other types of batteries that are not 1.5 volts. One of the most popular is the nine-volt battery, which is technically called a PP3 battery. Smoke detectors, garage door remotes, transistor radios and a variety of other devices use these batteries.
They’re pretty convenient, giving you the voltage of six batteries after only inserting one battery. In fact, that’s exactly what they are — they’re just containers that link six smaller batteries together. Here’s a picture of a nine-volt battery that was taken apart:
Each of the six batteries outputs 1.5 volts, giving a total of 9 volts when connected in series. The name brand nine-volt batteries usually contain six quadrouple A batteries (AAAA) which are rather uncommon in consumer electronics but find a home in medical devices such as glucose meters.
As you can see in the picture above, AAAA batteries are very close in size to AAA cells. That’s worth noting since they could save the day if you’re short on AAAs :)
