Solar panel trickle charge ?

[misteroboto]

I have one of those trickle charge solar panels that came with the car new.

I've been using it my work truck. The boss has it hooked up like a spaceship with computer, printer, gps, and satellite radio. The battery goes dead all the time in the Sprinter. I don't know how effective it is, but I figured it couldn't hurt.

I'm changing jobs so the panel is going on the shelf. Twice a year I check the water level, do a hydrometer test and run a trickle charger on it. I got that tip from the hermtdi battery maintenance thread. (Thanks, Herm!)

My question is, should I put this thing in the back window of the car into the accessory outlet once a week or so or keep doing what I've been doing and shelve it?

 

[rydogg]

Shouldn't your battery be sealed (i.e. no water level to check)? Mine is sealed.

To answer your question, are you running/charging anything while the car is off? If not, then I wouldn't really worry about it. If you've always got a cell phone or computer running off the battery, then it might be wise to keep it plugged in.

 

[Lug_Nut]

The factory supplied battery charge 'maintainers' have a maximum output of about 170 mA, if I recall. That's about 3 watts at their 18 volt potential.
That's in full, direct, no-haze, sunlight hitting squarely on the full panel.
Change the angle, add some overcast, put it behind tinted glass and output plummets from that low amperage. One spot of shadow on the cells and all the other cells try to charge that one, not feed the battery.
And then there's nighttime, dusk and dawn, early mornings and late afternoons....

The panels are intended to provide a daily average output to keep a full battery full, but not to cope with extra parasitic loads such as chargers the owner adds on.
Get a lighter socket multiplier with several outlet ports. Plug the devices and the panel into the multiplier, but don't put the multiplier unit into the dash.
If the devices don't maintain their stand-by capacity on solar panel power alone, then they are the source of the battery depletion.

Without those items (not needed for new job?) there may not be a need for the panel. Operating the vehicle for an hour a week should be more than enough to keep the battery sufficiently charged.
A trickle charger will put out 3 watts 24 hours a day, not just an hour or two with less power, or none, the other 22. Use the trickle charger if the car will be parked at home for weeks at a time.
The panel will be perfect when you leave the car at the airport parking lot for two weeks, but for other reasons? Shelve it.

 

[johnboy00]

3 Watts, not Amps.

 

[Lug_Nut]

DOH!
Corrected.

 

[ruking]

I would use a trickle battery charger at the very least. I have had a Battery Tender Plus for a few years.

Lug Nut pretty well has it covered. The real issue with VW's is the alternator (VW TDI anyway) is NOT designed to bring the battery up to full power. When you add to that the so called parasitic battery current draw, the battery is in some stage of pretty close to 24/7 current drain.

 

[40X40]

Shouldn't your battery be sealed (i.e. no water level to check)? Mine is sealed.

To answer your question, are you running/charging anything while the car is off? If not, then I wouldn't really worry about it. If you've always got a cell phone or computer running off the battery, then it might be wise to keep it plugged in.

There is electrolyte level that you can check. The cell caps are hidden under the label on top of the battery. Sneaky, huh?

Use distilled water only.

Bill

 

[Sprocket]

There is electrolyte level that you can check. The cell caps are hidden under the label on top of the battery. Sneaky, huh?

Use distilled water only.

Bill

While at Autozone the other day another customer asked the person behind the counter for some battery acid. I never knew they carried battery acid. Would this be better than adding distilled water?

 

[blaz]

While at Autozone the other day another customer asked the person behind the counter for some battery acid. I never knew they carried battery acid. Would this be better than adding distilled water?

I think that's for when the battery is dry (some new ones are shipped that way) or the plates heavily exposed from over-charging, over-heating or leakage. But if you've lost this much water, the battery's probably shot anyway. Otherwise distilled is good for top-up.

 

[misteroboto]

The factory supplied battery charge 'maintainers' have a maximum output of about 170 mA, if I recall. That's about 3 watts at their 18 volt potential.
That's in full, direct, no-haze, sunlight hitting squarely on the full panel.
Change the angle, add some overcast, put it behind tinted glass and output plummets from that low amperage. One spot of shadow on the cells and all the other cells try to charge that one, not feed the battery.
And then there's nighttime, dusk and dawn, early mornings and late afternoons....

The panels are intended to provide a daily average output to keep a full battery full, but not to cope with extra parasitic loads such as chargers the owner adds on.
Get a lighter socket multiplier with several outlet ports. Plug the devices and the panel into the multiplier, but don't put the multiplier unit into the dash.
If the devices don't maintain their stand-by capacity on solar panel power alone, then they are the source of the battery depletion.

Without those items (not needed for new job?) there may not be a need for the panel. Operating the vehicle for an hour a week should be more than enough to keep the battery sufficiently charged.
A trickle charger will put out 3 watts 24 hours a day, not just an hour or two with less power, or none, the other 22. Use the trickle charger if the car will be parked at home for weeks at a time.
The panel will be perfect when you leave the car at the airport parking lot for two weeks, but for other reasons? Shelve it.

Thanks lug nut. On the shelf it goes.

 

[misteroboto]

Shouldn't your battery be sealed (i.e. no water level to check)? Mine is sealed.

To answer your question, are you running/charging anything while the car is off? If not, then I wouldn't really worry about it. If you've always got a cell phone or computer running off the battery, then it might be wise to keep it plugged in.

Here is a link to the battery maintenance thread: http://forums.tdiclub.com/showthread.php?p=606172

 

[rydogg]

Here is a link to the battery maintenance thread: http://forums.tdiclub.com/showthread.php?p=606172

Domo arigato, misteroboto.

(I tried not to, but I just couldn't help myself)