Carefully Remove the 9V Battery to Find the Smaller Batteries Inside
If you’ve ever hacked electronics , you’ve probably had the illusion that most gadgets are screwed up for you. For example, 9V batteries are just six AAAA batteries stuck together.
As reddit user usgiorgi notes, many of the batteries purchased from major stores contain a smaller battery pack . For production reasons, this makes sense. This is also useful if you are creating a project and need to set up a power supply.
The rest of the components are at hand too. Reddit user CaptainKozmoBagel points out that you can salvage the top of a discharged 9-volt battery to make a new 9-volt connector with just a little wire . Please note that you should not tear up the old battery. Lithium-ion batteries (such as the ones used in your phone) can explode if you try to open them. The 9-volt batteries, on the other hand, are fairly safe to disassemble.
If you need a new 9V connector, simply solder the old 9V connector to the pins. | Reddit