Recommendation for Solar Panel to charge my Surefire Beast II HID

[mrwhite1]

I wasn't exactly sure where to post this, but since my goal is to have something capable of charging my Beast II HID, I thought I would ask here.

I will preference that I dont have any electrical experience, so please forgive my ignorance in terms of volt, watt, mA, etc...

I have been looking for some type of portable solar panels, and was wondering if anyone had any experience with them? I had originally been looking at the Brunton ones http://www.brunton.com/catalog2.php?cat=200 or http://www.powerenz.com/store/, but there are so many other brands thought I would ask for opinions.

I know the Beast II case has an input for 12V, and I notice that several of the panels can do 12V or use a converter to AC... but there are so many differences in the wattage / mA... what should I be looking for? Can someone recommend a particular panel that would work?

 

[N10]

can these solar panels really charge the beast 2 battery directly?...i don't know much about solar chargers but most of the ones i've seen seem to take a long time to charge batteries to full capacity(unless you're using arrays) and would the current they provide be sufficient? ok i gues i'm not helping but i'll wait for others to chime in..just interested in your question..

 

[mrwhite1]

Well there is the question? Will it? I haven't a clue... Just dont want to spend hundreds of $ on something that wont work. I was wanting a solar panel to put in my go bag, and figured I'd try to get something big enough to charge my laptop or anything else I might need. The Beast is the biggest thing I have that might need charged so I wanted to get something that could handle it. From some of the information I've been reading, for example on laptops, they recommend running panels to a battery, then a inverter off battery which would allow you to use the actual power cable for the laptop.
Since the Beast has both adapters I'm not sure if charging AC vs DC what the advantages / disadvantages would be.

The panels I was looking at all say 12V, but the amount of watts and mA are different. For example: The Brunton Solaris 26 is 26 watts (15.4 volts / 1600 mA) the bigger Solaris 62 is 62 watts (12 volts / 3100mA).

Or I could maybe couple the panel with one of their batteries and inverters and charge it that way, and let the panel recharge the battery...
http://www.brunton.com/catalog2.php?cat=200
http://www.brunton.com/product.php?id=604

It's all way over my head and it a bit overwhelming.

 

[gibbs]

Wild shot in the dark here, but if your light has one of those wal-wart type chargers, have a look at it, eg it may say 12v 1.5 amps or something along those lines. Assuming the light has an internal charging circuit to control the current to the battery, a solar panel with roughly the same rating should do the same as the wall wart would. By the way it may be rated in milliamps (mA) divide that number by 1,000 to get amps.

 

[SemiMan]

How fast do you want to be able to charge the battery? How big is that battery by the way, i.e. how many AH?

Semiman

 

[SemiMan]

Hard to find any info on the B1R-BK but I will make some guesses.

Battery pack says it is good for 2 hours so I will guess it is about 50 watt hours, maybe more?

I am guessing there is a custom Surefire charger? Is it only AC powered or is there a DC input? If there is a DC input is it 12V?

Hard to make any guesses about how efficient that charger is going to be. If there is any user's manuals or anything you could point to then could probably help.

Semiman

 

[mrwhite1]

Yes the charger has AC and DC input (12V) however there is no information in the manual about battery specs

 

[SemiMan]

Yes the charger has AC and DC input (12V) however there is no information in the manual about battery specs

Well 50 Watt-hours is a reasonable guess than.

The issue is likely the efficiency of the 12V input versus charging. It is likely a switch mode charger though so count on maybe 80% or more. So you need to put in at least 60 watt hours.

The problem with most panels is that while they say "12V", the "open circuit" voltage can be much higher, i.e. 18V under bright sun. Even under load they may be 15-16 volts or more. I would suggest calling Surefire and asking them how exact that 12V needs to be. No doubt you are not the first to try to do this.

Semiman

 

[electromage]

A plain PV panel will not charge a battery effectively. You need to add a solar charge controller to the equation. Some of the smaller kits include them, such as Brunton ones you linked to. At the very least you need a diode to prevent the current from going the wrong way when the panel is putting out less voltage than the battery. It would help to know what the current rating on the AC charger is.

The Beast probably expects somewhere around 12V in to charge effectively (10-15) maybe, if it's designed to connect directly to a car. You should find a system with a panel, charge controller, and a small sealed battery (AGM or gel). Then connect the Beast's charger to the small battery. That will give you the best results. You can then connect whatever 12V devices you might need to charge/power as well, even in the dark.

 

[mrwhite1]

I would suggest calling Surefire and asking them how exact that 12V needs to be. No doubt you are not the first to try to do this.
Semiman

I wish it were that easy... I have not had overly great success via email or phone conversation with Surefire about the Beast II. It's like no one knows anything about it... I usually get, "Well we will have to look into this and get back with you" and never do.
I wish I could speak to someone on the manufacturing floor that could give me specifics about it.

 

[SemiMan]

A plain PV panel will not charge a battery effectively. You need to add a solar charge controller to the equation. Some of the smaller kits include them, such as Brunton ones you linked to. At the very least you need a diode to prevent the current from going the wrong way when the panel is putting out less voltage than the battery. It would help to know what the current rating on the AC charger is.

The Beast probably expects somewhere around 12V in to charge effectively (10-15) maybe, if it's designed to connect directly to a car. You should find a system with a panel, charge controller, and a small sealed battery (AGM or gel). Then connect the Beast's charger to the small battery. That will give you the best results. You can then connect whatever 12V devices you might need to charge/power as well, even in the dark.

Actually a charge controller may not be needed at all. The Surefire built in battery charger IS the charge controller. The issue is what voltage it will take. Adding a charge controller with a battery may be needed if the Surefire does not have enough range, but keep in mind, unless you are using a high end MPPT charger, you may be losing a ton of output from the panel (20-40% or more).


Semiman

 

[electromage]

Indeed, a separate charge controller is probably only necessary for building a system with another battery.

At the very least, something to keep the voltage in the normal range produced by cars should help.