Recommended emergency jumpstart gadget?

[Malarkey]

There are several on the market, ranging from large devices with air compressors and other utility built in, to small devices that plug into the cigarette lighter ports. Does anyone have any personal experience with them?

I'd prefer one of the small ones and would really like one that you can just chuck in your car and forget about but I don't know if they hold charges for months (or years).

Any suggestions would be appreciated.

[jayman]

Don't get the cigarette lighter one. When powered down, the Prius cigarette plug is normally dead unless you specially modify it. So if the Prius 12 vdc battery gets too low, the cig plug booster won't work.

I got a basic 700 amp booster box from Canadian Tire. They were on sale at a 50% markdown. The reason I got such a high capacity one is that the Prius really shouldn't be used to boost other cars. Here in winter at -40, a surprising number of cars, trucks, minivans, etc die right at an intersection.

So far I've used the booster box to start an old Dodge K-car, a full size pickup, and a minivan. It helps a lot if you instruct the motorist to wait a minute or two for the booster box to try to charge the dead battery first.

The box cannot be ignored. It must be recharged after every use, otherwise once a month take it out and plug it in for an hour or so to ensure a full charge. If you just leave it in the car, I would guess after half a year the charge will be too low to be of any use to you.

The one I got from Canadian Tire had almost no charge when I got it out of the box. According to the sticker, it had been manufactured half a year previous.

[kohnen]

<div class='quotetop'>QUOTE(Malarkey @ Jul 9 2007, 09:46 PM) [snapback]475906[/snapback]</div>

There are several on the market, ranging from large devices with air compressors and other utility built in, to small devices that plug into the cigarette lighter ports. Does anyone have any personal experience with them?

I'd prefer one of the small ones and would really like one that you can just chuck in your car and forget about but I don't know if they hold charges for months (or years).

Any suggestions would be appreciated.
[/b]

I can think of two ways to come up with something you don't need to worry about for years:

1) Make one using a gel cell that gets periodically attached to the 12 V aux battery to keep a float charge on it. (I had mentioned in another thread the idea of having it connect every time the brake lights come on).

2) Take 8 (or 16, or 24) Everready 1.5V AA Lithium batteries and hook them into a package that puts out 12 Volts. Put some clips on it and, if the 12 V aux battery gets discharged, I bet that could put enough charge back into the battery to let you start up. (You would have to immediately disconnect the Lithium battery pack so that it doesn't receive a charge - lithium batteries HATE that!)

Either of these would permit you to forget about maintaining it until you need it.