Here’s How a Jump-Starter Works

What’s great about jump-starters is that they’re pretty simple machines when you start to dig into them, and don’t require a Master’s thesis to explain. So today, I’m going to dive into a short explanation and show you exactly how a jump-starter works using the Athena jumpstarter from Uncharted Supply Co. 

Quick, someone raise up Mjolnir to get this party started.

Think of a jump-starter as a handheld rechargeable battery. Within the jump-starter’s case is a series of battery cells that can hold a charge. Charging is essentially like you’d charge any other battery, in that you’d connect it to a wall—via a USB cable to an outlet for the Athena—or through your car’s 12V outlet. 

This charges the internal battery cells, which then holds the charge until you’re ready to throw that electricity at something. From there, you just jump your car as you would using normal jumper cables, although you don’t need the second car. You just hit the power button, attach the leads, and jump the battery back to life. That’s it!

What you do need to know, however, is that a jump-starter doesn’t charge your battery, despite popular thought. Instead, jump-starters provide just enough electricity to jump the battery back to life or provide just enough power to turn the engine over and get your charging system running. So you won’t be able to turn your vehicle off right after it starts, as these devices are purely for when your battery dies. 

If your alternator is DOA too, you’ll likely find yourself jump-starting your vehicle a few times. And it’ll likely be time to get both a new alternator and a new battery. 

Most jump-starters are good for anywhere between 10-20 jumps, depending on the size of the unit. Uncharted Supply Co.’s Athena is good for 20 jumps with a full charge, which should get you out of any sticky situation. 

Noco Boost’s Plus GB40, which is of similar size to the Athena can also provide up to 20 jumps with a full charge. But something larger and made more for professional garages like Schumacher’s ProSeries will double, if not triple those numbers. 

There are even some new batteries that have built-in jump-starters, such as Anti-Gravity’s motorsport batteries. 

For those that are more visual folks, here’s a jump-starter in action. 

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