tool idea - is this viable?

[vavet]

18V battery powered tools are popular.
Portable battery packs are popular for jump starting vehicles with dead/depleted batteries.

What would it take to use an 18V power tool battery as a vehicle jump starter? I'm imaging a slide-on or slide-over adapter with some alligator clip leads. I think the voltage would have to be stepped down to be compatible with a typical vehicle 12V system.

What's the right size battery to jump start a typical 4 cylinder or 6 cylinder gasoline powered vehicle? Let's assume the vehicle battery isn't completely dead, but just a little too weak to do everything it needs to do.

 

[K13]

How many amps does a power tool battery produce? I am going to guess nowhere near enough to boost a car.

 

[RaisedByWolves]

How many amps does a power tool battery produce? I am going to guess nowhere near enough to boost a car.

It would make a lot of cool smoke though.

 

[ItsNemo]

How many amps does a power tool battery produce? I am going to guess nowhere near enough to boost a car.

As far as I can tell, the typical Dewalt 5ah is good for ~50 amps peak draw...that's at 18-20v though. A pair of them and stepped down, you might be able to get close to 120 amps, which should be enough to start a vehicle with a weak battery.

I can't imagine those lithium jump packs are anything more than 18650 or 21700 cells in the end anyway and they're not delivering 1000 amps either.

 

[K13]

As far as I can tell, the typical Dewalt 5ah is good for ~50 amps peak draw...that's at 18-20v though. A pair of them and stepped down, you might be able to get close to 120 amps, which should be enough to start a vehicle with a weak battery.

I can't imagine those lithium jump packs are anything more than 18650 or 21700 cells in the end anyway and they're not delivering 1000 amps either.

All the ones I see say they are rated at at least 600Amps. Why would anyone want to carry around 2 separate batteries plus some sort of device to convert them into a jump pack when I can buy a dedicated unit that will more than likely outperform it for $130 CDN.

 

[slowtwitch73]

Endless youtube vids covering this....old idea

 

[ItsNemo]

All the ones I see say they are rated at at least 600Amps. Why would anyone want to carry around 2 separate batteries plus some sort of device to convert them into a jump pack when I can buy a dedicated unit that will more than likely outperform it for $130 CDN.

There's no way they deliver 600 amps for more than a couple milliseconds though.

I can understand the desire though, I keep tons of cordless tool batteries around and charged and know they'll still work after a few years. Seems most jump packs only last a few years themselves before the entire thing is trash. For a quick jump start of a neighbour or car out in the back 40, I could totally see something like this being handy.

My solution has just been a plug in charger with "starter" function, it's only 100 amps for starter but works every time.

 

[mogandave]

Would it not make more sense to use the portable battery packs as chargers for the tool batteries?