Coincidentally, when I turned the key in the ignition of my car ... starter to turn over, so you don’t really need a huge battery—5 amp-hours is often sufficient. Trevor Raab For the jumper ...

This is a fully automatic battery chargers with 3 charge stages. Automatic charging protects your battery from being overcharged. So you can leave the chargers connected to the battery indefinitely.

But jumping batteries on cars built after 2000 might not be so smart. Newer vehicles can contain dozens of computers and even more digital devices. Jump-starting a car with cables connected to a ...

If the car battery dies again or the jump start does nothing, call roadside assistance or buy a replacement battery. Often, stores will install a car battery for free, but call ahead to make an ...