schmidtj — I respectfully disagree. The link you give does not support your claim either — note their low Typical Drain currents compared with 10 A (10 000 mA). Their total charge capacity (in ampere-hours) may be high enough, but these batteries cannot supply a large current like 10 amperes while at the same time maintaining their voltage close to 12 volts. Their internal resistance is far too high. By the way, the TCH's absorptive-glass-mat type of 12-V battery does not have a high peak current rating, and so should never be used for jump starting another car.

Stan

I can't find any data on what the absolute maximum amperage a alkaline cell can produce at a reasonable voltage.
What if I take my 12 volt battery pack (made of of D cells) and attach it to the dead 12 volt battery. Let the battery pack dump itself into the dead battery to it's own self depletion. I "suspect" there is a good chance the 12 volt battery would now have enough capacity and amperage to start the car. Assuming the 12 volt battery is only discharged and not defective.
In effect I use my battery pack to "charge" the 12 volt battery and not directly power the TCH computer and inverter.

schmidtj — You could try looking at
http://batteryuniversity.com/
or
http://www.batterystuff.com/tutorial_battery.html
for starters.

Stan

You're assuming that TCH battery is totally dead. That should rarely be a case. Even if the 12V battery goes totally flat, it should recover some charge if left undisturbed for some time. Also the 10 Amp current is required only for few seconds to get the ready light, after that inverter will start charging battery from traction pack. I can assure you that any NIMH or NICD pack is capable of delivering more than 10 amps. I don't think you can do anything with 12v electric outlet inside the car since that is disconnected from battery when car is off, so direct connection to battery would have to be made, but if you make such connection you don't even need 10 amps either. Even if the battery pack can only deliver 1-2 Amps, let it charge car battery for few minutes and that should be enough.
I need to see if I can come up with some small battery pack , to use for jump start my TCH just in case. NIMH and NICD cells are more than enough but they don't hold full charge for too long and in few months they will not have enough charge left, also the voltage has to be higher than 12 V , probably more than 13 for electricity to flow but I need to check how much more than 13v is safe.
I think TCH 12 v system is rated at less than 100 amps, so directly cranking the starter with it is not a good idea, but you could charge the other car's battery with TCH for few minutes, then disconnect the cables and crank the other engine then.

what about those things that you just plug into the 12v DC to charge up a car. Would those work the same way?

No. Those receptacles are off unles your are in ACC or Ready mode. I carry something similar to two of these from my Prius days except mine have the larger clamps for attaching to the +12 volt battery post and a chassis grounding point. Never had to use them but my hope is they will dump enough energy into the 12 volt battery to be able boot the system and get the car going.
http://keyon.en.alibaba.com/product/...p_Starter.html