Hi guys,

I don't use my car that much, as it's got stop/start I want to make sure that the battery keeps a good state of charge. I've been looking around and there is an AA branded solar charger that plugs into the ODB port and will trickle charge the battery. Has anyone used anything like this, are they any good, dangerous to be plugged into the OBD etc.....

TIA

Martin

Oh, here's a linky to the one I'm cosidering....

https://www.amazon.co.uk/AA-Essentials-AA1432-Battery-Charger/dp/B084M5ZL5L/

Can’t help you with the solar charger but I have an intelligent charger that I can recommend.

I purchased one after it was recommended on the forum in a thread earlier in the year. See link below.

https://www.ebay.co.uk/itm/121219067543

I find it very good and use it as and when required.

I am looking at getting one of these as well.  Most of them (including the one you link to) have a standard 12V connector which feels more appropriate to me as long as the socket stays live with ignition off.  I think anything under 10W is maybe a bit under powered and will struggle to keep up with the normal drain.  I was looking at this one but not yet ordered and tbh some of the reviews aren't great:

https://www.amazon.co.uk/TP-solar-Maintainer-Cigarette-Alligator-Motorcycle/dp/B07RXKN9MF/ref=mp_s_a_1_24_sspa?dchild=1&keywords=solar+car+battery+trickle+charger&qid=1596808792&quartzVehicle=29-405&replacementKeywords=solar+car+battery+trickle&sprefix=solar+car&sr=8-24-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExTUdSTU9GRUswMUVFJmVuY3J5cHRlZElkPUEwODAxOTM1UlM1NTJDN1g5RUFOJmVuY3J5cHRlZEFkSWQ9QTAyMzM5NzMyM1kxODJQUkRSQ01RJndpZGdldE5hbWU9c3BfcGhvbmVfc2VhcmNoX210ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

I got an AA branded cordless car vacuum before and it was not great quality so I wouldnt assume it is quality just because it had AA printed on it.

IMO the charger must reach 14,7V to actually charge the battery. My car service ppl said, that using normal charger in a Focus with S/S system will only keep the car awake, and end up with no added charge. I saw it myself last winter, when I was trying to load with a normal setting and not the AGM setting.

Additionally, does a charge coming through the cigarette lighter plugin go through BCM and get registered?

A small 10w 12v solar panel will typically put 0.25A on a sunny day into the car battery. This is such a small charge that a solar controller would not be needed if the leads were connected directly across the battery. The solar panel should have an inbuilt diode to prevent it draining the battery at night. And it needs a fuse inside. This might just offset the battery drain and stop it going flat. Anything less than 10w will not charge the battery properly.

I used a solar charger on my last car, One of those fold out ones (made by Sealey) with a built in diode, and and LED that lit when charging. It wasn't great! I started off getting a 12v socket installed that was permanently live - if it's controlled by ignition it won't charge when you take the key out of the ignition. Even with that, the battery would drain. Then, I connected it directly to the battery with the supplied cabling. This also didn't improve matters. (The car was only used a couple of times/month) but I still ended up jump starting it. I finally solved the issue - I sold the car LOL

From memory, I think I once measured about 200mA with strong sun. Honestly, you are better off with a proper trickle charger plugged into a 13A socket!

This is my one of choice with a great feature that even after a power cut, it will resume charging automatically without any intervention, most will need you to reset it. You won't know you need that feature till you leave your car on holiday for 2 weeks and have a power cut on day 2 LOL

 

Stephen. Maybe a 20w solar panel connected directly across the battery might work. I think I am being optimistic expecting 0.25A from a 10w panel. A 20w 12v solar panel with a diode and fuse connected direct to the battery might work if you can not use a trickle charger.

15 minutes ago, Kevin#95 said:

Stephen. Maybe a 20w solar panel connected directly across the battery might work. I think I am being optimistic expecting 0.25A from a 10w panel. A 20w 12v solar panel with a diode and fuse connected direct to the battery might work if you can not use a trickle charger.

I just checked my 'Sealey' box (SPP01), it is rated at just 1.5W  LOL I also tried another brand which I also just checked and it  is rated at just 4W. Maybe a 20W one will work, this was a couple of years back, pretty sure I couldn't get a 10W or 20W one then!

53 minutes ago, StephenFord said:

This is my one of choice with a great feature that even after a power cut, it will resume charging automatically without any intervention, most will need you to reset it.

Agreed, that was my suggestion earlier in this thread.

1 minute ago, PLB said:

Agreed, that was my suggestion earlier in this thread.

It was probably me that recommended it in the thread you took the suggestion from LOL I've been wasting money on chargers for 40 odd years now and this is the first one I have ever wholeheartedly recommended - frequently!

Agreed. Smart charger is a better method if you can use it.

 

7 minutes ago, StephenFord said:

It was probably me that recommended it in the thread you took the suggestion from LOL I've been wasting money on chargers for 40 odd years now and this is the first one I have ever wholeheartedly recommended - frequently!

Yes, thanks for the original recommendation 👍