Recommendation for a Solar Car Battery Charger ?

[Mako Koiwai]

Our little Miata racing battery died after a month of inattention. Any thoughts on using one of those solar chargers that one can plug into the cigarette lighter in order to keep ones little used battery topped up?

I understand that typically constantly trickle charging ones battery isn't a good idea, as opposed to using a SmartCharger, that periodically trickle charges. I've got a SmartCharger, but the car port doesn't have any near by power outlets.

Can one even charge a Miata through the cigie lighter?

[Christine Grice]

http://www.harborfreight.com/battery-di ... zmap=97853" onclick="window.open(this.href);return false;

[Christine Grice]

also found this:
http://www.batterystuff.com/solar-chargers/" onclick="window.open(this.href);return false;

[Aaron Goldsmith]

http://www.harborfreight.com/battery-di ... zmap=97853

works good for me.

[Mako Koiwai]

So you're saying that by using the quick release battery terminal ... I can extend how often I need to charge the battery?

The battery we're using ... yah ... bought the same one again ... only has 120 CCA, 8 amp hours ... weights 6.3 lbs.

[Craig Naylor]

Brings back memories of trying to get my '71 Volvo wagon back from college (St Louis) in '88 with the entire roof covered in solar panels as the alternator was dead, and it was going to take weeks to get a replacement. (Dealer provided them as the alternator was only months old and under warranty, but the wasn't one left in the country to be had.)

Car actually managed to make it all the way home on those panels. But boy did we get everyone attention on the drive home. People actually thought the car was powered by them.

[Christine Grice]

So you're saying that by using the quick release battery terminal ... I can extend how often I need to charge the battery?

Since you are the one who doesn't like it to be too quiet around here, I won't give you the answer right off the bat.
Question: Do you know why your battery goes dead after sitting for an extended period of time?

[Mako Koiwai]

I could google/wiki that ... but rather extend this thread.

btw. "your" link was the first thing I came across before starting this thread ... but I didn't find the answer there about solar chargers and detrimental constant trickling. Perhaps solar down time is enough to keep it from being "constant trickling?"

[Bob Beamesderfer]

When your racing batter wouldn't start the car did you try jumping it? I had to do that a couple of times before I got a trickle charger. I ended up with a Craftsman smart trickle charger and it kept the Odyssey ready to go.

You either need to disconnect the battery from the car's electrical system or keep it charged in some way. Modern cars all have a level of dark current draw that will flatten a small battery quickly.

[Greg Peng]

Any thoughts on using one of those solar chargers that one can plug into the cigarette lighter in order to keep ones little used battery topped up?

The Subaru/VW dealership where I was in southern Maryland used these on the new cars that were stored in their back lot. My mechanic friend there didn't mention having any problems using these chargers.

[Mako Koiwai]

When it wouldn't start ... i trickle charged if for about four hours (our regular charger stopped working) ... when it still wouldn't turn over I jump started it with a "power station" ... let it idle for at least a half hour while I washed the car, then drove it around the block. Turned it off and tried to start it again and not a peep.

Does anyone know ... is the ('99) Miata cig lighter "open" without a key in the ignition? Ours doesn't work at the moment with or without key. Fuses seem fine?

[Kurt Rahn]

When it wouldn't start ... i trickle charged if for about four hours (our regular charger stopped working) ... when it still wouldn't turn over I jump started it with a "power station" ... let it idle for at least a half hour while I washed the car, then drove it around the block. Turned it off and tried to start it again and not a peep.

Does anyone know ... is the ('99) Miata cig lighter "open" without a key in the ignition? Ours doesn't work at the moment with or without key. Fuses seem fine?

A guy who fixed mine in the G35 said that with all the stuff we plug into the 12V outlet these days, the circuit tends to short out. It may be the connection in the back of the outlet.

[Bob Beamesderfer]

When it wouldn't start ... i trickle charged if for about four hours (our regular charger stopped working) ... when it still wouldn't turn over I jump started it with a "power station" ... let it idle for at least a half hour while I washed the car, then drove it around the block. Turned it off and tried to start it again and not a peep.

Does anyone know ... is the ('99) Miata cig lighter "open" without a key in the ignition? Ours doesn't work at the moment with or without key. Fuses seem fine?

That's not enough driving. Could have put it back on the trickle for a day also.

The outlet itself has a fuseable link, sounds like that's burned out. Those links aren't very robust, which is why I never tried charging my Miata through the lighter.

[Jayson Woodruff]

Okay, more to this that you think.

If your loosing a lot of charge, like in two weeks, figure out why. Dying battery, amp leakage, etc.

Even race batteries should give you a month hooked up of stand by and a few months of disconnected standby. So if you're going off one month at a time, I'd use the disconnect, if you plan on several months at a time, think about a charger.

Unless something is wrong, a small solar cell should float the battery. It needs to be rated 14.4V and have a non-reversing diode in it (to prevent the battery from draining in the shade). A few watts should do it. So long as your charging device doesn't raise voltage your battery will handle it long term just fine.

Many cars have a relay that disconnects the cig lighter from the battery when you shut it off. Someone might know of a simpler way to test this, all I can think of is using my power supply and ampmeter to see if I could drive charge into the lighter. I don't too many non-electronics geeks have this equipment though.

Batteries self discharge faster in warmer weather. That might be what you died this month and not last month.

Jay W

Our little Miata racing battery died after a month of inattention. Any thoughts on using one of those solar chargers that one can plug into the cigarette lighter in order to keep ones little used battery topped up?

I understand that typically constantly trickle charging ones battery isn't a good idea, as opposed to using a SmartCharger, that periodically trickle charges. I've got a SmartCharger, but the car port doesn't have any near by power outlets.

Can one even charge a Miata through the cigie lighter?

[Rick Brown]

The solar panels we use for the timing lights are for charging through a cig lighter outlet. $20 at Harbor Freight, regularly on sale for ½ of that.

[Arthur Grant]

Can one even charge a Miata through the cigie lighter?[/quote]

You can always get the cig lighter to battery clamp converter and go directly to the battery. If the charger is inside the car I dobut the sun would be on it long enough during the day before falling into shade to be a problem. There are however circuits you can install to protect the battery.

As an example there is the 7Amp Solor Charge Regulator ($29.99) from Harbor Freight. http://www.harborfreight.com/7-amp-sola ... 96728.html" onclick="window.open(this.href);return false;
7 Amp Solar Charge Regulator
Item # 96728

Protects and regulates the charge of a 12 volt battery
Three LED indicators (charging, discharge, overcharge)
Three connections for battery (two-way plug), solar (two-way plug), and load (3" pigtail)
Overcharge protection at 14 volts
Discharge protection at 10.5 volts
Maximum input voltage: 22 volts
7 amp
100 watt

The charge regulator provides both overcharge and discharge protection. The regulator will automatically shut off power input form the solar panel to the battery to prevent damage to the battery.

[Steve Collins]

I think I saw a long lasting 20% Harbor Freight discount coupon in last issue of GRM.

[Richard Jung]

So you're saying that by using the quick release battery terminal ... I can extend how often I need to charge the battery?

The battery we're using ... yah ... bought the same one again ... only has 120 CCA, 8 amp hours ... weights 6.3 lbs.

Told ya, 2 or 3 Dekas = 1 Odyssey.

[Mako Koiwai]

... new Deka arrived and charging. The old one caused the charger to Fault Blink.

[Arthur Grant]

... new Deka arrived and charging. The old one caused the charger to Fault Blink.

What kind of charger are you using. If it's one of the schumachers the high end model will fail and ignore a battery that low end model will bring back to life. I have both there top of the line which I use on my boat, and their cheap model which I frequently use on my cars and trolling motors. It is an oddity of the automation.

[Mako Koiwai]

Question: Do you know why your battery goes dead after sitting for an extended period of time?

OK ... I give up

[Will Kalman]

Question: Do you know why your battery goes dead after sitting for an extended period of time?

OK ... I give up

Boredom and lack of purpose in life?

[Bob Beamesderfer]

Question: Do you know why your battery goes dead after sitting for an extended period of time?

OK ... I give up

Boredom and lack of purpose in life?

Lonliness?

[Steve Ekstrand]

Fibromyalgia?

[Mako Koiwai]

Question: Do you know why your battery goes dead after sitting for an extended period of time?

... it was Christine that was calling us out