A jump starter and a battery charger are two different machines and are not interchangeable. The most important distinction to make in understanding the differences between the two is this: a jump starter does not charge your car battery.
A jump starter produces a powerful jolt of energy to your battery via the two cords attached to it. The jump starter in most cases is battery operated and is charged up and ready to go when you need it. Its only job is to produce singular shots of electricity to revive the battery.
Think of it as a defibrillator for your car: after one good burst of energy from the jump starter, your cars “heart” (battery) can begin beating again.
Jump-starting you car only takes a few seconds and requires some follow up; once you shock your battery back to life, you are often required to drive around in your car for a while (usually 20-35 minutes) to give your battery a chance to recharge itself.
It sounds counterintuitive, but that’s how a car battery usually keeps itself charged. If you don’t drive around and give your battery a chance to recuperate, your battery may die again.
A battery charger is different. A battery charger slowly feeds energy into a dead battery. They can be very useful if you don’t need to use the car right away and have the time to wait while it charges.
Just like you plug your phone into a phone charger, the charger for your car battery will slowly charge your battery.
In reality, it’s sometimes better to charge your battery with a car charger over a period of time if your schedule allows it.
However, many if not most people rely on their vehicles for everyday transportation, and can’t simple wait around for their car battery to charge over the course of hours. That’s when a jump starter comes in handy.