Can I recharge my own battery with the trickle charger I use on my lawnmower?

Dear Car Talk

Dear Car Talk | Jan 01, 2000

Dear Tom and Ray:

We spend five months each winter in a warmer climate and store our other car in the garage. When we return, the battery is always run down. There's no short, so it
must just be running down from disuse. I have a small trickle charger that I sometimes use to boost my lawn mower battery. What if I hooked it to my car battery, and a
timer unit turned it on for 20 minutes or so each day? To help save you time, I'm providing you with three possible answers: A) This has to be among the two to three
dumbest ideas we have ever heard. You'll burn up your car and enlarge the ozone hole in the Earth's atmosphere; B) This is a stroke of genius. Wish we had thought of
it. Get a patent on it and become a millionaire! or C) Disconnect your battery and reset the clock and radio settings when you get back. -- Roy

RAY: Well, first of all, Roy, we want to thank you for your thoughtful and considerate approach. If more of our readers gave us questions in the form of multiple
choice, we'd get a lot more of them right.

TOM: Not necessarily. But in this case, our answers are A and C.

RAY: Someone already has a patent on something like this, but we don't recommend it. It's just too risky to play around with that kind of electricity when you're not
around to monitor it. It'll probably work, but what if something goes wrong?

TOM: Right. Which would you rather do when you get home after the winter, Roy? Charge up the battery overnight and reset your radio buttons, or sift through the
charred remains of your furniture and personal belongings looking for your fire-insurance policy?

RAY: Here's what I'd do. I'd either disconnect the battery, or just join a road club, like AAA. For 40 bucks a year or so, they'll come and jump-start your car whenever
you need them to. So when you get home from Florida or Arizona or wherever, you call them up, they come out and start the car, and then you drive around and let the
battery charge itself back up.

TOM: The only problem is that sometimes you have to wait a long time for the road service to show up, and that's inconvenient. Wait! I've got it!! Put in your call for
road service BEFORE you head south for the winter!

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