How are you protecting yourself from a dead battery? I was going to rely on Lexus roadside assistance, but a store had a jumper cables sale, and when I browsed the aisle I saw battery powered jump starters. I had not heard of these before. Reminded me of the battery advertised on TV 20 years back, with a turn switch to use the built in reserve battery, in case the main battery died. It made the capacity of the main battery less, but may help out in a jam.

My questions before I buy a jump starter are (a) what strength jump starter would be needed to jump an IS250, (b) how often anyone who has one of these has to plug in the jump starter (I don't want to be plugging it in every 6 months) and (c) are some brands better than others?

 

I have two portable jumpstarts that's been through so many jumps without failing. In fact, I haven't charged one of them in a year, and I've used it on probably 10+ cars before. I've charged from a Honda accord to a Chevy 2500 Diesel truck. Since your IS is a relatively small car when it comes to an electrical standpoint, you may not need a large jumpstart. In fact, I bought mine from Home Depot (Husky). Invest in one that's at least $40, and you'll be fine.

Always carry a jumper cable even if you have the portable jumper and roadside assistance.

 

those all in one jumpstarters(air pump, charger, starter) things are pretty good. We had a benz e240 die out on us because of a dead alternator. We jumped the car, and had a concept to charge the batterie with the jumper all the way back home (around 4 miles with 1 stop light)

comes in handy

 

jumper cables for me, we have one of those charger thing at the dealer and although it's more convenient, that thing weighs 40lbs and not exactly space-saving to take on trips and such. Plus you have to recharge after every use or else no charge at all

 

I've used one of the all in one deals (charger/light/air compressor) it's awesome! You hardly ever have to charge it as it packs a pretty hefty punch. They are heavy though...

I've also used it when my alternator died to get back home (6miles)

If you can spare the room and the weight I'd totally recommend it!

 

Are you sure it's the same charger we're talking about? The ones we have are portable units that weighs maybe 8lbs and is no larger than a small printer. The ones in the shop are usually charger units where you can trickle charge the battery, or charge it at full load. They require larger batteries and circuit boards, hence the large and heavy platform.

 

oh sorry I meant yes, you and I are talking about the same thing. I might have gotten mixed up about the weight, but they are quite heavy. I'm not talking about those ones that have wheels on them, although we also have them at the shop, they charge slooooooowww.

I also have those battery charger that you plug into the smoke lighter. they're quite handy although not as effective

 

I just weighed mine. It's 10lbs. You need to work out if you think they're heavy The ones in the shop are suppose to charge slow, hence trickle charging. But these jumpers in our cars are not chargers though. They're just batteries that are suppose to deliver power at startup as if they're the primary. The jumper I have can deliver up to 400A at startup. Never had trouble jumping any vehicle before.

 

I use those portable jump starters. Easy, cheap, and works every time. I've used it on many occasions. I've even used it to move my wrecked SC400 from the yard to the garage and back without a battery. Just clipped the jump starter pack to the battery terminals and started it up, removed jumper pack, and moved car. They are getting cheap and smaller now days that I'd probably buy one for every car I had and just leave it in the trunk.

As for weight, I have one of the older larger ones that are about 2X the size of a lot of the smaller newer ones I see now and it does have some weight to it, but probably no more than 20 lbs. My wife who is 5'1" had no problem getting it out of the trunk and using it herself.