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Solar battery chargers for cars

Luzern
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Solar battery chargers for cars

Anybody got or used one?

We're relatively well provided with public transport, and so our car does not get a deal of use. Result flat batteries catch us out, ( and soon back inside to phone breakdown assistance Roll eyes). Amazon and Halfords are advertising solar chargers, that plug in to the EOBD diagnostic port, and leave on the dash.

What do you think of the idea?

No one has to agree with my opinion, but in the time I have left a miracle would be nice.
44 REPLIES
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Re: Solar battery chargers for cars

what is it charging? other than itself.
as it can't be charging the car battery just by being plugged into the ODB port surely.

anyway, a car that rarely moves, it's not just the battery being flat that can be of concern.
other parts not moving are going to be an issue too, depends how long it's sitting idle though.

i'd suggest it would be better to just buy a jump pack, rather than wasting money on a device that relies on the sun to charge anything.

Luzern
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Re: Solar battery chargers for cars

@chenks76 Not that with you with my fuzzy brain, but here's a describing one.

No one has to agree with my opinion, but in the time I have left a miracle would be nice.
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Re: Solar battery chargers for cars

yes, but i don't understand how it manages to trickle charge the battery via the ODB socket.
looking at the images there are clips that physically connect to the battery, it would seem that this needs an actual physical connection to the battery also.

anyway, at £22.49 for that i'd rather just take the car a 5 minute drive twice a week.
there's more than just the battery that can go back in a car not being used.
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Re: Solar battery chargers for cars

@Luzern   Having a quick "google" on the halfords offering.... it says " suitable for batteries up to 250Ah"... so you would do well to confirm the spec of your battery, and check with Halfords spec to make sure it matches or is above your battery spec

 

It looks as though there is a long cable with two clips ( as normally found on battery chargers) to connect to the battery terminals... Make sure that these clips and the wiring, is not in contact with the bonnet when closed.

 

@chenks76  From checking out the AA version... which states that it uses the EOBD port ... and your question about what is it charging...  HUH !?

 Solar panels generate electricity... so cannot "charge itself" as you allude to in your response.

 

Checking out the  "pin outs" on the EOBD socket it appears that pins 4 & 5 are "GND" /chassis/earth... and pin 16 is 12v + from the battery...

 

a pinout pic.png

 

Ipso facto... if you can get 12v + on pin 16 when connecting across to GND/Chassis.earth   then you can also send a current back down those wires TO the battery to charge it....  (as if connecting directly to the terminals via the red and black crocodile clips from a charger )..

 

 

alanf
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Re: Solar battery chargers for cars

From @Luzern's link

"Please note: the charger can only be used while the vehicle is parked and off. It is not waterproof and should not be left outside."

A bit limiting for a solar charger?

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Re: Solar battery chargers for cars

i still say it will be better for the car to just take it a short drive regularly to keep everything ticking over.
having a £22 device trickle charging a car battery unattended might not be the best idea someone ever had.
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Re: Solar battery chargers for cars

@chenks76  assuming you can start the car... !....

 

Hence the o.p. request  !....

 

one could argue that taking a car for a spin round the block every day, will also increase local pollution levels, which would be considered by some people on this forum to be a criminal offence.

 

 

  having a £22 device trickle charging a car battery unattended might not be the best idea someone ever had.

 

 

Hmm.... so ... do you plug in your phone... ipad .... whatever... or your 12v 4amp charger in your garage, and sit and watch it all the time?     chargers are supposed to be left " unattended".. and designed to be used that way ! ! ! ...

 

 Moderator's note by Mike (Mav): Quote fixed.

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Re: Solar battery chargers for cars

i was saying that rather than let the battery go flat in the first place, to keep the car ticking over thus the battery doesn't run flat, and as i said there is more than just the battery that you need to worry about should a car sit idle for long enough.

i don't have a garage so it's a moot point, but if i did i wouldn't plug my phone into charge in a garage then go away (never mind sit and watch it).

however to compare charging a phone to a 12v car battery would require a level of intelligence that is lower than the average or a reddit user. i assume you are not putting yourself in that category.
and, no, chargers aren't "supposed" to left unattended. you very often see advice saying that you should not left devices charging unattedned and there is always a risk.

and those considering driving a car to be a criminal offence are even lower on the scale of intelligence than those that would compare a charing a car battery to a mobile phone.
i would go as far to say that they are [-Censored-] idiots !!

Moderator's note by Mike (Mav): Avoidance of swear filter edited as per Forum rules.

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Re: Solar battery chargers for cars


Luzern wrote:

What do you think of the idea?


but back to the OP.

I would say it's a stupid idea.

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Re: Solar battery chargers for cars

I think you would need to go for more than a five minute drive to keep the battery well charged.

I suspect it takes a good run to get the battery back up to full charge as just starting the car takes a fair bit of energy out of the battery, tempature also affects things as some people have found to their cost on a freezing morning when the car fails to start.

If you have a garage, simply buy a battery charger and charge your car with the battery in situ but with the earth and positive leads disconnected, with old cars you could get away without disconnecting the leads but in modern cars there are too many fancy electronics that could go wrong.

Another possible option depending on model of car is to charge the battery via the cigarette lighter providing it has a live connection when the car is switched off.

Personally I would not consider any solar device I cannot see how it could generate enough power in a reasonable amount of time.

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Re: Solar battery chargers for cars

The solar panel chargers, as quoted... (halfords & AA ).. are "trickle chargers"...  therefore they do not charge a battery "from flat" to "starting condition" in a short period of time....  

   they work.. on the principle of keeping a small charge going into the battery, to counteract the "natural discharge" when not in use... thereby keeping the battery in relatively good order, so that when it is required for use, it has sufficient charge to be able to turn the starter motor, and the engine over, to get the car started.

 

Because it is "solar powered"  it is the "modern tech" of the old 2 amp trickle charger sold by many  motor accessory shops... all of which were "generally" left "unattended" during the night, trickle charging batteries all over the country.

 

 

RJM
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Re: Solar battery chargers for cars

I have the "AA" charger that plugs into the "EOBD" port.

 

Excellent piece of kit as long as you have a good battery in the first place.

Don't be tempted with models that can only be used via the cigar lighter or crocodile-clips as they are not so good.

I do not use my car during the week now and I have found this charger absolutely brilliant in keeping the battery fully charged. 

Here is the link for the AA with a full description; I purchased mine from ebay instead and saved a fiver.

 

https://shop.theaa.com/store/home/car-battery-solar-charger

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Re: Solar battery chargers for cars

@RJM  Exactly what the O.P. was wanting... and confirming what I have already posted.

EnglishMohican
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Re: Solar battery chargers for cars

Charging a phone (at high current to get the charge time down) is way more dangerous than trickle charging a 12V accumulator at the 200ma that the AA unit supplies when it is absolutely flat out. The recent Samsung exploding phone experience and the Sony Laptop battery disasters of a few years ago all go to demonstrate that. The accumulator charging does need to be done sensibly but 200mA and 12.7V max seems unlikely to produce much in the way of hydrogen.

The problem with a car may be that all the modern electronic gadgets (electronic locking, alarm etc) consume more power over 24hours  than the charger supplies in that time so the battery still ends up discharged. Also, winter is the worst time for accumulators and the time when the sun will produce least charge.

I do use a solar charger to maintain a 12V accumulator and it is very successful. I get a fully charged battery whenever I use it but it's not on a car so not quite a fair comparison. The charger sits behind the windscreen equivalent sloping at about 45 degrees and faces the sun much of the day. It is smaller than the AA one so normally only produces about 50mA but there are no gadgets attached so every bit helps. It has survived 5 or 6 years without a problem.