In the case of the Schumacher IP-55 model (12V 4Ah battery) the descriptive
term that's not been mentioned so far, is 400A Peak, for this model.

Manufacturers know that Peak is a (multi)million dollar word, whether it's
used with watts, HP, or amps.. because Peak distorts actual specifications.
Consumers love big numbers, and manufacturers know it.

With a properly rated current shunt, and a peak-reading amp meter attached,
one could determine the peak current available from such a small battery.

As Dave P points out, the number of times that a small battery can deliver
the somewhat severe duty discharge rates, is going to be a very limited
number of times.

I didn't purchase this Schumacher power pack as an emergency car battery
jump pack, but instead, only as a portable power supply.

--
Cheers,
WB
..............


"David Nebenzahl" wrote in message
.com...

OK, your impeccable documentation has won me over. I withdraw my
objection; the current claims on those jump-packs (300 amps, 400 amps)
must be believable after all. I'm a little surprised, though.