Between the invention of the self starter and the end of the 20th Century, the best portable car jump starters weren’t something you carried with you. They were heavy lead-acid automotive batteries ...

There’s only one way to answer the question, “Is it my battery, or something else” when your car won’t start: Hook up the best car battery tester and get a readout of what’s going on. Skip the ...

You can check the health of your iPhone's battery to determine when it's time for a replacement.

It's easy to tell if your iPhone is charging when it's turned on, but a little more difficult when it's powered off. Here's ...