Easy battery charger via cigar-lighter?

[solvitquick]

May have dreamt this, but I thought I saw an advert for a home-power-up device which could then be plugged in to the cigar-lighter to power the battery. True or false? P.S. I know there is a glove-box jump-starter but no good for me at moment - but may buy one after present probs are solved. Ty all.

[ChuckFickens]

You may or may not be able to trickle charge the battery through the cig lighter... it depends on the car.

Far easier and better to get a trickle charger that you connect direct to the battery.

[solvitquick]

Yup, you right (again) Chuck, safer anyway - I believe cigar (actually cigarette lighters lol) are best for that purpose-only, for those who need them.
SIQ.

[gingejbee]

If your car is parked outside, you could try one of these:

http://www.maplin.co....trickle-charger-98358

Two different neighbours use these and have never had trouble starting ...even in last winter's very low temperatures. They just leave the unit on top of the dash and plug into the lighter socket.

[Khandro]

I can understand how you can charge a battery from a donor car, ie. your neighbour's, thus depleting his battery, but how on earth can you charge a battery from itself via the cigar lighter?

[Hopkirk]

Yes but Gingejbee, they might just have good batteries.

Our Astra, which I bought new in December 2003 is still on its original battery and never has a problem starting. It also does lots of short journeys.

[Khandro]

OK, I now get it; it's solar powered.

[jomifl]

many cars have a diode that prevents trickle charging through cigar lighter sockets. Don't expect a 300 milliwatt solar charger to do anything other than maintain charge and support the electrical devices that a running when you lock up the car and leave it. Buy a cheap generator that you can keep in the boot if you don't have access to mains power for charging. For the same price you can get a new battery which should cope with the coldest winter.

[gingejbee]

Both of the cars I refer to above are second cars and are little used - perhaps once or twice a week, standing outside most of the time.
I was not suggesting that this solar trickle-charger would do anything for a flat or partly-charged battery - simply that it would maintain a good charge in an infrequently used one.

[solvitquick]

Yup, gang I get your messages loud and clear, ty all. Best answer difficult to choose but I'll keep to the simplest advice. For info by the way, car in garage and never outside. Solar-powered is never for me in home or any small devices except garden-lights (weak and decorative only).
Unlike many ABers (sad the way they ask a question, get the knowledge and disappear - so unfair after so many devote time and wisdom to answering) I WILL nominate a best answer.
So, I'll mark as best answer (close between ChuckFickens and jomifl) to: ChuckFickens! But ty all, very educative.
SIQ.

[Khandro]

If the car is kept inside a garage, isn't it still possible to have the device outside, say on the roof, and still connect it to the car via the cig. lighter?