It'll Never Work!

Just had to charge my car battery and found myself pondering (very briefly) as to why they don't make a battery charger that plugs into the cigarette lighter!

Ever thought of an invention that just could never work?

You mean like one of these?

http://www.amazon.co.uk/dp/B000VWQXJO/ref=asc_df_B000VWQXJO6448244?smid=A3P5ROKL5A1OLE&tag=googlecouk06-21&linkCode=asn&creative=22206&creativeASIN=B000VWQXJO

powdered water.

Nice try, Carl. An impressive gadget, but that's just carrying a spare battery with you!

True, but it does support your theory

I suspect they dont charge this way due to the fire risk. Any sort of problem and those cables heat up or even melt then you wil be in trouble

Would make sense to have a socket under the hood thoug rather than battling with cables and trying to work out what to connect to what

I have a couple of useful gadgets like that though. Jump leads that are powered via the cigarette lighter and my tyre pump is powered in the same way. I have used them to help others several times.

Gary

Ummm! I think there may be a point being missed here...

Dead battery powering the cigarette lighter to charge itself? Think about it.

The cigarette lighter works off the battery.... if the battery is dead... the cigarette lighter is dead too.

 What you need is basically what Carl has posted up (an auxiliry battery) which is somehow hard wired to the main battery, but only discharges on demand.

Well done, Wayne! Now read the title and the OP again!

I think Lee is the only person that got the point.

The device I posted acts as a boost rather than a charger or a replacement battery. Its meant to give a battery with low charge a boost.

I suspect another reason you can’t use the lighter socket as a charging point is the number of amps needed to charge a battery, The leads from a battery charger has great big thick cables in order to cope with the amps. The leads leading to and from the lighter socket are much thinner and would melt with that many amps  passing through them - Net result = 1 burning car.

Probably a lot worse in a truck where everything is 24v and twice the amps. Take it from someone who plug a phone charger in to a trucks lighter socket thinking it was the normally 12v. Lots of sparks and blue smoke later and I had one very dead phone

I think any invention (if made complex enough with redundant backups) can work.

The old example has always been the solar powered torch.... which has since been invented as it converts the solar energy to charge the battery rather than discharge it instantly.

The same can be said with your idea.... it's not impossible to design a battery within a battery whereby the second battery only conects to the main batter terminals on demand (basically like a set of jump leads but built into the structure of the battery). Yes, it would be unreasonably large and heavy, but that's more down to the components needed to make a car battery being heavy in the first place.

The principle itself however is sound.

I cannot think of any invention that cannot be made.. as long as it has the right components to make it work disregaring practicality and expense of course.

Honestly, you couldn't make it up.

Steve's point is that you can't charge a dead battery from a cigarette lighter because the battery's dead. That's why he titled the post "It'll never work".

He then asked for similar flawed ideas. Lee came up with "powdered water" (just add water - geddit?)

Come on lads...

I always thought it odd that builders never did the roof first, to keep them dry.

 You do know that powdered water does exist???

But in the spirit of it.... what about an inflatable dartboard??

It's ok, I got the point, right away so don't worry, it didn't fly past me. It just started me thinking about the different gadgets I have come across.

Gary