need an Electrical engineer to explain this, jump box Options

[r_towle]

Hi,
I have a 997 (this feels like the start of a support group thing)

This car has an electric front hood latch.
So, the battery needs to be hooked up to open the front hood where the battery is...
Its not logical, but Porsche put in a shortcut.

So, go to the fuse box inside, pull out a red lead, and hook up a 12VDC battery to this lead, and chassis ground...
Hood opens.

Instead of using a full size heavy car battery, I went and bought a lithium battery "jump box" thing
Schumacher SL1639 Lithium Portable Power Pack and 1000A 12V Jump Starter

So, it will not work.
We ended up getting a full size battery, with jumpers, just to open the hood, so we could reconnect the battery.

My question is...WHY does it not work?
When I put my meter on it, I see 16VDC
ITs fully charged.
Its on.

The Tech support told me the unit can only be used for jump starting a car.
The mechanic at the shop told me he also had this issue, and the unit needs to see a load??

I will return this if it will never work...but I really need to know why it won't work.
I can get a motorcycle battery, or some other unit that will take care of my needs...but this thing should work...yet it does not.

Anyone care to explain electricity to me?

Rich

[mepstein]

These will fit in the palm of your hand and start a large truck with a dead battery. I’ve personally used it on the truck. It’s what I purchased for my daughter. Gets high reviews.

[fixer34]

These will fit in the palm of your hand and start a large truck with a dead battery. I’ve personally used it on the truck. It’s what I purchased for my daughter. Gets high reviews.

Sorry, there is no way in hell that unit will provide 1000amps unless you measure the time in milliseconds. The clamps themselves would melt after 2-3 seconds.

[Superhawk996]

These will fit in the palm of your hand and start a large truck with a dead battery. I’ve personally used it on the truck. It’s what I purchased for my daughter. Gets high reviews.

Sorry, there is no way in hell that unit will provide 1000amps unless you measure the time in milliseconds. The clamps themselves would melt after 2-3 seconds.

Agree on the 1000A rating - marketing hype.

Ratings are like cheap stereo ratings of old - optimistic and rated at peak.

However, research how lithium ion batteries perform. They can be designed for peak energy or peak power. A single 18650 cell can deliver 30A in short repetitive bursts. Pouch cells can put out even more current due to large surface area of the anode and cathode. This ability to deliver very high power out of such a small package is what makes Lithium ion batteries dangerous if used improperly and/or short circuited.

It is VERY EASY for these small jump packs to crank a completely dead vehicle (with or without vehicle battery) with a very small footprint and light weight. Used to use them a couple times a week. Way better than hauling around those old lead acid jump packs.