Often, the only liquid level indicator you need is your eyes, such as when looking at your cold beverage on a summer’s day. Other times, though, it’s useful to have some kind of indicator light that ...

Sometimes we need a non-contact liquid level sensor. There are several ways to build that, but the easiest is to try an optical liquid level sensor. You may already have an idea in mind since you are ...

A new kind of battery stores energy in what researchers are calling “rechargeable fuel”—electrodes in liquid form. The result can be either recharged like a conventional battery or replaced by pumping ...