The jump-starter boxes have been around for a while and having jumped my share of cars and trucks I never really thought they would work that well with a battery half to a third the size of a car battery. So when my sister gave me one for Christmas ...... oh.....that’s nice thanks her son is a motor head racing stock cars so I bet he had an influence on the gift. So I opened it up and charged it and noticed it has a accessory cigar lighter outlet with compressor and I thought it may work for ham gear so once charged I hooked it up to a 2 meter radio via the heavier clamps and worked a few local contacts for 2 hours last night while charging an HT from the outlet. This morning the guy next door asked for a jump on his POS truck again so I used the jump-starter and the truck started on the first crank. Looks like I underestimated the value of of this tool for starting vehicles and use as a portable 12 volt power station.
These use a "Trick" of Physics, to make a near Dead Battery, act like a Charged Battery, for a very Short Time.... What they do, is use a Source, that has a very Low Impedance, in the Charger. This dumps High Amps into the low Battery, that causes the Electrolyte to be Heated, which then allows the low Battery to develop a much higher Current Pulse, before it goes flat, upon Cranking. If they use a Lithium Ion, NMH, or NiCad, this is what is happening. If the source is LeadAcid, then that Battery will have very Thin Plates, with Lots, and Lots of Surface Area. That lowers the internal Impedance of the. battery, compared to the Starting Battery, in the vehicle. Isn't Knowledge, WONDERFUL.......
Mine works great (used it on my folks boat a couple of times), holds a charge for a good long while and will power my CPAP machine all night on the lighter socket. Oddly enough I can get a full night of CPAP but can't fully charge an iPhone 4...oh well.
Every "jump box" I have ever opened up (more then a few) has had a sealed lead acid battery. The battery I have found in all cases is the same style I have found in emergency lights and some higher end uninterruptible power supplies. Most of the boxes I have had work well if the car battery is just a bit low to turn the engine, and the car usually starts right up. When the car battery is totally dead, or the car requires extended cranking to get it to start then the box may or may not work. Don't run the box down to far and it will last a good few years. Just treat it like a standard lead acid battery. As a side note, did you know they make a wire feed flux core welder too? I don't remember the manufacturer but it is based on the same jump box technology. It is pretty good for light duty welds in a pinch when there is no power.
I may have to revisit these. My Daughters bought me one several years back, I don't remember the brand but it was red-I know, no help Anyways it was a POS. Wouldn't jump a small car, let alone one of my diesels. I've never thought much of them since, but like I said, I may need to rethink this Thanks for the post.
Actually, I have been planning to buy one, but there are so many choices I have not been able to select a clear winner yet. Any input from those who know which ones are Best?
@kellory - I have a rather old Everstart 300amp booster. They don't make it anymore and I had to resort to ebay to get a decent picture of it (attached). Here are a few URLs that do comparisons: 2015 Top 10 Jump Starters Comparison Top 10 Best Jump Starter Comparison & Reviews. Best Jump Starters of 2014 based on Expert Reviews | Best Jump Starter 2014
I carry this one from Northern Tool. It's a little pricey. You need to buy the battery seprerate from the box. I like the fact that it has a air compressor, led light, and a 450 watt inverter built in. The best part is being able to replace the battery without having go all McGyver on it. NPower Flex Powerpack XL 6-In-1 Powerpack/Jumpstarter, Air Compressor System Item# 24928
watch this product demo video on the website. Amazing. Antigravity Micro-Start XP-1 | 126-882 | J&P Cycles HINT: he doesn't stop with the motorcycle. A little steep but worth having, I'd say. As for tires, I have one of these in each vehicle. Amazon.com: Campbell Hausfeld RP1200 12-Volt Compact Inflator: Home Improvement For bikes, take off the plastic case, it makes a tiny package. Like this: Motorcycle Tire Air Pump - webBikeWorld KMart was selling them for like $13 a few months ago, but this isn't such a bad price. People talk about finding them at Northern Tool and such but I didn't find any locally.
I have one of the bigger ones (like you've pictured here), though don't think it's good for anything but jumping a vehicle. My next one will likely be one of those small Li-ion models, that's got a body no bigger than a Thermos jug. Mostly, I'm looking for a good jump starter, that doesn't weigh as much. For my own use, my Jeep is a stick shift, so I should be able to get it started by rolling it, and popping the clutch.