A hidden gem on Amazon, this portable charger is tiny, compact and ready to power up your devices on the go. Today, you'll ...

9V batteries are often found in devices that aren’t used very often. If you use a NiCd rechargeable battery you may find it completely discharged by the time you need it. Capacitors on the other ...

All of the common disposable alkaline batteries from AAA to D are single cells. The exception is the 9v battery which actually has six smaller cells inside of it. [Tom] took a look inside three ...

A mini UPS with 5V, 9V, 12V DC output and optional PoE can be used to power a WiFi access point, a broadband router, an SBC, ...

Here's how to safely set steel wool (also called wire wool) alight using nothing more than a 9V battery. It's not difficult but you must take care as the wool and the dish can get very hot - adult ...

This is the product's overall performance score, based on key tests conducted by our industry experts in the CHOICE labs.