In the past when you needed a battery powered jump starter you were relegated to older lead acid batteries which made the units extremely heavy and large. Also they would lose their charge quickly if left idle for a period of time.
Lead Acid Versus Lithium-Ion.
But in the past many years easily available Lithium-Ion powered battery jump starters have quickly taken over the market. These fancy little units pack a large punch in a very small package. Plus with the advantage of very little self discharge so they are usually ready to go when needed.
So now jump to the power tool world and how it can take advantage of the large power reserves sitting in their 18 volt Lithium-Ion packs. In the past the smaller capacity 3.0 Amp Hour packs would have been a bit of a struggle to pull off a full jump of a car with a dead battery. Especially if it was a work truck with a large V8 engine. Or God forbid trying to start a large diesel engine from a jump starter. But now that we are seeing regular packs up to 6.0Ah from most manufacturers and then to take it even further with Milwaukee having packs all the way up to 12.0Ah the battery capacity threshold bar has been raised by leaps. And then to mix things up more you can include Makita with their X2 platform but instead of running this device in series to get 36V they could design the two packs in parallel so you would be at 18V with double the capacity. And then also included in this would be to run a Dewalt Flexvolt pack in regular 20V fashion to take advantage of the Amp Hours.
Here is a couple quick mock ups of what we predict will be coming down the pipeline in the future.
Makita X2 Jump Starter Running in Parallel for up to 12.0Ah (with 2 6.0Ah packs) of Power.
Milwaukee M18 Automotive Battery Jump Starter Mock Up.
As a related note way back in the day I was on a job site where a crew member had a dead battery on a piece of equipment. The only thing they had handy was a Dewalt 18V Ni-Cd pack. They rigged up some thick gauge wire and some alligator clips and sure as heck it started the piece of equipment. Now this was just an average sized motor from a small skid steer but it was still impressive to see that little battery crank it up. This little trick always had me thinking that one day we would see a device purpose built to use power tool batteries for such a use.