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Car troubles strike when you least expect them, and the three most common reasons to call a tow truck or roadside assistance are a flat battery, a flat tire, or no fuel.
When it comes to a flat battery, numerous jump starters exist that you can attach to the battery to give it a boost to get your car going. One of my favorite brands is Noco, and the company offers a range of jump starters -- from small to enormous.
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The only catch to these jump starters is that you have to keep them charged up. And if the jump starter happens to be flat itself when you need to use it, it can take hours to charge up to the point where it will in turn fire up a vehicle.
This is where batteryless jump starters come into play.
Unlike traditional jump starters that require a charge before jump-starting a car, this Rezervo Batteryless Jump Starter only requires a quick charge from a weak battery to get the car started.
Note: The branding on my batteryless jump starter is different from the one linked below, but the specs are comparable.
Instead of having a battery, these use components called ultracapacitors, and rather than needing to be charged before firing up a vehicle, these can be charged up from the car's flat battery in a matter of minutes.
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Yes, you read that right. It draws the power it needs from the flat battery. (Note the difference between a flat battery and a dead battery: A flat battery has used up all its charge but can be jumpstarted and will continue to work properly once charged. A dead battery has no residual charge left and therefore cannot be jumpstarted.)
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You connect the batteryless jump starter to the flat battery, wait while the ultracapacitors draw tiny amounts of power from the flat battery, boost it, and feed it back into the battery to start the vehicle.
And it really is that simple to use -- everything you need to know is printed on the jump starter.
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Connect the red to positive, marked with a +, black to negative, marked with a - (there are protections built into the jump starter in case you connect it the wrong way), press the ON button to charge up the ultracapacitors, wait for the two green lights to come on and you're ready. (On diesel systems with glow plugs, press the GLOW button to change the way the jump starter delivers the power.)
Now try starting the vehicle. It's that easy!
I like these batteryless jump starters a lot, and while I've yet to have a flat battery, I've used mine to quickly and safely jump-start a lot of other people's vehicles.