Car battery solar chargers

[simonbav]

Good morning all,

many years ago I used a 2.5 watt solar charger like this,

ECOARROW Solar Battery Charger 12V 2.5 Watt Solar Car Trickle Charger Waterproof Portable Amorphous Solar Panel Kit for Motorcycle, Boat, RV, Marine, Snowmobile https://amzn.eu/d/iOgdRzk

In the hope it would trickle charge the 12v battery in a significant way to ward off discharge.

Now that I understand watts divided by volts equals amps and have practical experience of the paltry levels of charge going into some LED lamps I bought for my workshop,

https://spvlights.co.uk/collections/solar-lights/products/solar-led-light-bulb

i wonder about the worth or value of this 28 watt solar trickle charger.

Limited-time deal: BigBlue 28W Solar Charger Foldable with Digital Ammeter, Outdoor Solar Powered Charger With SunPower Solar Panels Dual USB Ports(5V/4A Overall) for iPhone iPad Samsung Galaxy LG Cellphones and Devices https://amzn.eu/d/6gGbi1q

I don't have mains electricity where I keep my Landy and there is no drain on the battery when its parked up. What have others found in relation to solar trickle chargers?

  

Simon

[Scotty]

Hi Simon, I personally use Oxford Products Solariser for my motorbikes, I only use one of the bikes in the summer months and my modern bike ( which has stop start and Drl's ) I use for around 9 months of the year, I normally stop riding from December to March the rest of the time they are connected to the Solariser,I have never had an issue with either batteries, the reason this is my optimiser of choice is it's a well known brand in the motorbike world and was recommended by a couple of work colleagues that use them for there bikes and it's easy to use, mine is connected to the batteries all year around and when I stop using it for the winter I just undo the battery panel and plug it in, they are 12v so will work with a car battery, I should also point out that it still works on cloudy days  Paul

[Craig T]

I'm not sure if that panel you linked to on Amazon gives a 12v charge does it, looks like it might just be USB charging to me?

I have just put a new solar powered electric fence energiser in the field this morning. This has an internal 12v sealed lead acid battery, 12v, 8Ah and the solar panel is a 10W unit apparently. They reckon the panel will keep it going even through the darkest days of winter and off course the battery keeps it going overnight.

I almost bought a new fence battery, just like a car battery but suitable for deep discharge so more of a leisure battery and a separate solar panel to keep it topped up in the field but then the costs were very similar to this new unit and to be honest, I'm getting too old for carrying car batteries across a muddy field!

For keeping an already topped up 12v car battery going with no load on it I'm guessing you wouldn't need a really powerful solar panel?

Craig.

[Mycroft]

I have a 10W solar unit on top of my lock-up, keeping my truck trickle-charged. It does lose charge over time, but a hell of a lot less than nothing at all, allowing me to work on my other truck for weeks on end, yet still get a good restart. 28W sounds very useful indeed, although presumably you'd have to swap the usb end for some crocodile clips. If I was starting over, I might go for this bad boy - cheaper and 8w less than your unit, but dedicated to car battery charging:

https://www.amazon.co.uk/POWOXI-Upgraded-20W-Solar-Battery-Charger-Maintainer-Controller-Solar-Panel-Motorcycle/dp/B07TY3HGF7/ref=sr_1_18?keywords=car%2Bbattery%2Bsolar%2Bpanel&qid=1698673563&sr=8-18&th=1

[simonbav]

Thanks chaps. I've some useful experiences to go by. I like the sound of the Powoxi one.

[NoBeardNoTopKnot]

Got one on my lawnmower. Never dared try, would guess you won't want to START your engine with one plugged-in. I can see this frying your charger.