Solar powered trickle charger?
Solar powered trickle charger?
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Discussion

RizzoTheRat

28,959 posts

222 months

Wednesday 3rd August 2022
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Think this is the one I've got
https://www.amazon.co.uk/AA-Essentials-AA1432-Batt...
Connects via the ODB port so easy to plug in when leaving the car for a bit. I got it as I was leaving the car unused for months at a time, no idea how the battery would have been without it but I had no problems starting the car after a couple of months unused.

ETA: Looks like that's an updated version and comes with a fag lighter connector too, which would be even easier than the OBD port, but obviously check your fag lighter is permanent live not ignition switched.

Edited by RizzoTheRat on Wednesday 3rd August 09:57

Scrump

23,943 posts

188 months

Wednesday 3rd August 2022
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I have this one:
https://xenta.co.uk/tv-and-home-entertainment/gadg...

Worked fine in the Summer, not so good in the Winter.

Scrump

23,943 posts

188 months

Wednesday 3rd August 2022
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nuyorican said:
Oh so they do exist then! That's good. Do you leave them connected full time?
I left the panel on the rear shelf but pulled the plug out of the lighter socket when using the car. Not sure if it was necessary to disconnect.

Mine has a regulator which is apparently worth having to stop over charging of the battery and also to stop the panel discharging the battery overnight (which seems to be a possibility). Again I am not sure if it is really necessary but it came with the panel so I used it.

RizzoTheRat

28,959 posts

222 months

Wednesday 3rd August 2022
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I only use mine when I know I'm leaving the car for a long time, and unplug it before starting the car.

Worth thinking about the size vs usage though. You probably need around 3-4 Watt hours to start a car, so mine would need nearly an hour in full sunlight to generate that much power, and on and a cloudy day solar panels will only be generating 10-20% of thier usual power, so 5 to 10 hours to replace the charge from a single start.

Scrump's one should charge in about 1/3 of the time mine does.

OutInTheShed

14,651 posts

56 months

Wednesday 3rd August 2022
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I tend to think that if you're starting your car twice a day and running it for ten minutes each time, it should keep the battery charged.

I use a solar panel on my boat to keep the batteries topped up. I've got an old 10W panel which is more than enough. These are now quite cheap on ebay.

I recently got a 50W panel for £39, this seems to give enough charge to make up for using cabin lights, nav instruments, charging phones and tablet etc.

General guidance seems to be you can just install a small panel and not bother with regulators etc, if the panel Wattage is less than about 1/10 of the battery capacity in Ah. So a 5W panel should be fine for a typical car battery. Given that it's behind a windscreen and probably shaded more often, you could probably go up to 10W

These are the people I bought from:
https://www.ebay.co.uk/itm/252394102201?hash=item3...

Another handy thing:
https://www.ebay.co.uk/itm/265720760745?hash=item3...

lighter socket usb adaptor with volt meter. A cheap and cheerful thing that charges my phone and tells me a lot of useful stuff about the alternator and battery. You've just prompted me to buy another one!

QJumper

3,238 posts

56 months

Wednesday 3rd August 2022
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If you've run your battery flat a coiple of times then it's possible your battery's had it, as it should fine if used every few days.

As for solar chargers, I have an OBD port one, and it says to disconnect before starting the car.

Personally I'd be replacing the battery before thinking of solar chargers.