If you live in a cold climate, you have probably occasionally had trouble starting your car on an especially cold morning. Aged or weak 12-volt lead-acid batteries seem to give up the ghost at the most inopportune times. In the old days, you would pull out your jumper cables and hope a good Samaritan motorist would stop to give you a jump or call for roadside assistance. A few years ago battery-powered portable jump start boxes hit the market. They could start your car, but because they contained lead-acid batteries they were heavy and bulky and were usually used primarily by car dealers or roadside service crews.
Fortunately, now there is another option: a new generation of mini jump starters that use lightweight but powerful lithium-ion batteries that can boost a dead battery and help the vehicle start. They are small enough and light enough (usually around a pound) to store in the trunk or the smallest ones even fit in the glovebox. What’s more, they can do a lot more than just start a car.
On the booster side, all battery boosters come with jumper cable clamps that allow the box to connect to the dead battery terminals. Some come with reverse polarity protection, a nice feature. Also available on some models is a semi-permanent cable and connector that lets you attach the booster without having to use the clamps on the dead battery. Just plug it into the special connector and start the vehicle.
Besides jump-starting, portable packs also provide electricity for a variety of purposes. Almost all of them will have a flashlight or emergency lantern. The power pack has USB ports that let you charge your cell phone or a variety of other personal electronic devices. Some come with built-in air compressors that let you fill a low tire or blow up an air mattress. When equipped with an inverter they can also provide regular AC power at a campsite or during a power failure, You can’t run your AC or refrigerator, but a desk light and maybe a radio or small appliance will be possible. You can also run your laptop computer several times longer than it will go on its built-in battery.
Prices are all over the map, depending upon the features you are looking for. Typically a bare-bones jump box will start at around $70, while fully equipped ones (which will be bigger, heavier, and much bulkier) can run into a few hundred dollars. It depends on your wants and needs.
All of this is made possible and affordable by the increasing energy density and reducing cost of lithium-ion batteries—a direct result of the growth of electrification of the transportation system.
Kevin Clemens is a Senior Editor with Battery Technology.