Playing with a "battery maintenance" solar panel?

[zuren]

I was helping a friend clean out his aunt's home with permission that I could take anything I wanted. I grabbed a few things with one of them being a "Solar Guard 12-volt Battery Maintenance System". It is one of those dashboard solar panels that back-feed through the cigarette lighter to keep a battery topped up, similar to one of these:

http://www.sportsimportsltd.com/1-5..._content=pla&gclid=CPr9s63C0bICFQJx4AodiDsA5w

I don't know anything else about it and haven't found any specs. In direct sunlight I measured 19v at the connecter and 15.4v in a shaded area. Other than it's intended purpose, is there anything else useful I could do with this? I'll probably snip the wire and put a set of Anderson Power Poles inline so I can connect other leads. But just looking for some ideas!

Thanks!

 

[MakersTeleMark]

You could hook it up to a 12v fan to stay cool in the sun.

 

[JIMBO]

:sombrero: They're not really good for anything except trickle charging (milliampere) and then only when the battery is already fully charged-

If you use the pwr outlet in the dash, it probably won't work anyway, because most ofem are "hot" only when the ignition is on-

An AC battery maintainer is better at home --

:costumed-smiley-007:wings: JIMBO

 

[zuren]

:sombrero: They're not really good for anything except trickle charging (milliampere) and then only when the battery is already fully charged-

If you use the pwr outlet in the dash, it probably won't work anyway, because most ofem are "hot" only when the ignition is on-

An AC battery maintainer is better at home --

:costumed-smiley-007:wings: JIMBO

Surprisingly, the outlets in both my car and van are always hot so it would still work as designed to trickle charge the batteries.

I was wondering about wiring it to a holder for rechargeable AA batteries (for example)? Or (not the best option) be able to directly connect it to a HAM or CB radio to get a message out if the batteries were drained? Just thinking out loud...

 

[JIMBO]

:sombrero: No, it wouldn't operate a multi watt ham unit and I doubt that it would even produce the 4w required for a CB--

Never say never though, although it would take some ingenuity to be able to provide the HOOKUP required for a radio-

:costumed-smiley-007:wings: JIMBO

 

[4x4junkie]

Definitely won't run a 2-way radio of any type that puts out more than 1 watt or so (plus it's voltage output not being regulated could damage something too).

It could work somewhat for the AA batteries, though if the current is much less than 200ma (which I suspect most likely it is), you won't get a full charge into them with just one day's worth of sun.

 

[wirenut]

A "battery maintainer" is only good for barely trickle charging an already charged battery. It won't run a CB, ham, TV or anything else. It probably won't run much of anything directly. Most of those panels are good for far less than 1 amp. Now you know why it was being given away.

 

[zuren]

I sent a note off to the company asking if they can send me some information about the unit but I'm not hopeful they will respond.

I need to get better using my multimeter with measuring milliamps. I see a similar kind of panel in NorthernTool that advertises as 2.5W so it is probably in the same ball-park. In full sun, measuring 20v, if it is a 2.5W panel that is 0.125a. However, if I was doing it right, it could have been close to 0.600a. I'm not sure I had the meter set up correctly. It was not enough power to spin a 12v computer cooling fan.

In any case, at the very worst I can use it as it was originally intended. My van doesn't get driven much in the winter.

Thanks for the comments!

 

[MakersTeleMark]

If it wasn't enough to spin a computer fan, I doubt it will do much for your battery.