Every car, not only older ones, can have battery issues – particularly if you leave it unused for a month or more. But traditional battery-booster packs are huge, heavy, and aren’t the type of thing you’d want to carry around. Enter the Cobra JumPack, which relies on Lithium-ion batteries to shoehorn a useful amount of charge into a unit no bigger than a small paperback book.
The JumPack’s Lithium-ion battery relies on the same Lithium-Cobalt technology used to pack as much power as possible into small handheld electronic devices such as phones. It shoehorns 6,000mAh into its rugged plastic casing, which is a little more than most laptop batteries. It can supply a 180-amp starting current, with a peak of 360 amps.
This is actually a fair bit lower than traditional portable jump-starters, which may offer as much as five times the peak current; a car with a big engine might require a battery with 700 cold cranking amps. However, if your battery isn’t completely flat, the JumPack needs to simply make up the difference, and its abilities should prove more than sufficient in most instances – unless you drive a truck, that is.
A rubber flap covers the contacts for the jump-start cable, which is a little short, but the JumPack is light and small enough to be positioned near the battery that you’re trying to assist. Jumping car batteries isn’t its only ability, either. There’s a USB port available too, which can supply up to 2.4A at 5V. So you can charge up the average phone at least three times.
There’s a brightly lit LED strip on the top, near a big green-ringed button, which you press to determine remaining capacity. Press and hold the button and a second LED on the front lights up, so you can use the JumPack as a torch.
I tried the JumPack with a three-litre, four-cylinder car – a Porsche 968 – that had been left unused for too long and wouldn’t start from its own battery. This vehicle needs quite a hefty load of amps to turn the engine over due to the capacity of the individual cylinders. To my surprise, it took only a few attempts to get it started, and the JumPack still had three-quarters of its charge left.
There are two options for recharging. You can either use the cigarette lighter adapter, or the micro-USB port – although no mains adapter has been included for this. But at £80, the JumPack isn’t particularly pricey, and an essential gadget if you don’t use your car that often. It’s small enough to keep in your glove compartment, or you could even carry it around with you at all times, just in case.
At time of review the Cobra JumPack was available for £80.