Trickle Charger on Cigarette Lighter?

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Ethanh100
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Trickle Charger on Cigarette Lighter?

Post by Ethanh100 »

I need a new trickle charger for my M6, and I thought that it would be very convenient to have one that plugs into the cigarette lighter outlet so it could easily be plugged and unplugged rather than having to get to the battery. This way when the car sits for a week or so during the on season, I can throw it on the charger and keep the battery in good health. I have read some conflicting info online however and people say that it can damage the electronics of the car, however that seems to be with newer cars. Im only talking 1-3 amps, so well within the rated amperage of the cigarette outlet. Does anyone use these style chargers or see any reason why I shouldn't? Thanks!
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jps635
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Re: Trickle Charger on Cigarette Lighter?

Post by jps635 »

I've done this for a number of years now, using a C-Tek charger. See pic. Works fine and I have a modern ECU.
I do the same with my boat.
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Re: Trickle Charger on Cigarette Lighter?

Post by GRNSHRK »

I'm using a Black & Decker model BM3B on my 6er, works great, comes with all sorts of connection options, and I don't recall it costing more than $25 of so =D>

I also have a BMW smart charger which I use on the cabrio, but it was quite a bit more expensive and has less connection options :-?

But both of these plug into the cigarette lighter socket and haven't had any problems with either \:D/
:mrgreen:
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Re: Trickle Charger on Cigarette Lighter?

Post by Pod »

I'm sure using that lighter socket would be absolutely fine. Although it doesn't sit well with me.............

Maybe a better solution would be to install a dedicated socket, wired directly to the battery, which could be located somewhere out of sight. I would feel much happier doing this as I could be sure that the wiring was of sufficient gauge and easy to check from time to time.

Has anybody had an under-dash electrical fire in a car? I had one once when a plastic after-market rear defroster switch overheated and ignited in heavy London traffic (going around the Elephant & Castle roundabout). You would not believe the amount of choking, blinding smoke which came from it in just a second or two.

An experience I do not wish to repeat!
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Re: Trickle Charger on Cigarette Lighter?

Post by Tommys 89 635 »

I'll disconnect the battery after driving and usually 3-4 weeks I will connect it to a charger to make sure it's fully charged.
Last edited by Tommys 89 635 on Mon Nov 23, 2020 5:03 pm, edited 1 time in total.
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Re: Trickle Charger on Cigarette Lighter?

Post by jps635 »

Maybe a better solution would be to install a dedicated socket, wired directly to the battery, which could be located somewhere out of sight.
Is what I did above^^. Maybe isn't clear, that's a lighter socket next to the isolating switch
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Re: Trickle Charger on Cigarette Lighter?

Post by Pod »

jps635 wrote: Tue Nov 17, 2020 6:04 am
Maybe a better solution would be to install a dedicated socket, wired directly to the battery, which could be located somewhere out of sight.
Is what I did above^^. Maybe isn't clear, that's a lighter socket next to the isolating switch
I was responding to the original poster and hadn’t really looked at your installation, which is exactly what I was suggesting. There’s no way I would risk charging a car via the cigarette lighter socket as I think its a fire waiting to happen!

Just my 2c 😉
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Re: Trickle Charger on Cigarette Lighter?

Post by sansouci »

My Ctek has an accessory cord that has ring connectors on 1 end for direct attachment to the battery and a polarized connector on the other that attaches to the charger. No alligator clips needed
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Re: Trickle Charger on Cigarette Lighter?

Post by nick88highline »

I use a CTEK charger connected to this:

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It's a DIN socket, so slightly smaller than a cigar lighter and it's protected by a 7.5amp fuse. A magnet and reed swtich operate a flashing LED on the check control panel when the hatch is open so I don't drive off with the charger connected...I wonder why I added that ](*,)
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Re: Trickle Charger on Cigarette Lighter?

Post by GRNSHRK »

Ya know, you guys are scaring the shit outa me :shock:
There’s no way I would risk charging a car via the cigarette lighter socket as I think its a fire waiting to happen!
I checked the specs on the Black & Decker unit and the output is only 1.2A/12.6VDC :-"

And IIRC, the fuse on the cigarette lighter circuit is 25A :roll:

I also don't think that companies would make these devices to charge through that socket if there was that much danger or possibility of causing a fire [-X

Anyhoo, I may just disconnect them and charge once a week, something like that approach, since you guys got me thinking :-?
:mrgreen:
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Re: Trickle Charger on Cigarette Lighter?

Post by Pod »

I checked the specs on the Black & Decker unit and the output is only 1.2A/12.6VDC :-"
B&D :shock: :shock:

I found out to my cost many years ago that B&D produce crap equipment. I never buy anything made by them and you should do yourself a favour and throw it in the dustbin!

Just my 2c 😉
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Re: Trickle Charger on Cigarette Lighter?

Post by hornhospital »

Why? Just because some piece of B&D equipment you had was faulty, then everything they make is crap? Beg to differ. I have several B&D saws, cordless drills (one 15+ years old) , corded drills, and jig/saber saws. Most are 10+ years old. ALL of them still work well. I've never had one fail, and I am NOT gentle with them. They get USED.

Your mileage may vary.
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Re: Trickle Charger on Cigarette Lighter?

Post by RossDinan6 »

GRNSHRK wrote: Tue Nov 24, 2020 6:29 pm Ya know, you guys are scaring the shit outa me :shock:
There’s no way I would risk charging a car via the cigarette lighter socket as I think its a fire waiting to happen!
I checked the specs on the Black & Decker unit and the output is only 1.2A/12.6VDC :-"

And IIRC, the fuse on the cigarette lighter circuit is 25A :roll:

I also don't think that companies would make these devices to charge through that socket if there was that much danger or possibility of causing a fire [-X

Anyhoo, I may just disconnect them and charge once a week, something like that approach, since you guys got me thinking :-?
You are correct, the fuse is 25 amp. A little trickle charger is not a problem for the lighter socket. I wouldn't worry about it.
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Re: Trickle Charger on Cigarette Lighter?

Post by GRNSHRK »

Thanks for confirming Ross, as i really didn't think this was an issue to begin with :roll:

I just shuffled the green beast and cabrio around in the garage, preparing to do some work on the TS wheels, but won't say anything about that, just yet :-"

Both cars are back on the trickle chargers [-(

One last thought, I'm fairly certain that once the battery is up to snuff, the current draw reduces and only draws as charge is required, being "smart" chargers :-k
:mrgreen:
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Re: Trickle Charger on Cigarette Lighter?

Post by RossDinan6 »

Just to be sure you are aware, small maintenance chargers like Battery Tender will not charge the battery. That is not what they are designed to do. They can not supply the voltage and amperage necessary to charge. They will maintain the battery in a float stage. Be sure the battery is fully charged before storage, then hook up your maintainer.
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Re: Trickle Charger on Cigarette Lighter?

Post by emac »

I just have a hardwired lead from the battery and dangle it out of the trunk. It plugs into a Battery Tender (Deltran). sometimes I unplug it and leave it hanging out and sometimes I toss it in the trunk. Big fan of Deltran products. I have leads on lots of stuff and always wire straight to the battery.
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