Solar recharging of AA- and D-size batteries [Archive] - Glock Talk

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DJ Niner
08-27-2011, 22:05
Here's what I'm looking for: A solar rechargeable battery system that will charge 2-4 AA batteries or 2 D batteries, at near-47-degrees N latitude (North Dakota), even under less-than-ideal conditions, in less than 6 hours, for under $100. I would prefer an off-the-shelf solution, but if I have to cobble something together to get it, as long as I know in advance that it will do what I need done, then I'll build it.

Seems like most of the small battery solar chargers are ~$30 cheesy plastic trickle-chargers that barely work in full desert sunlight, or they are relatively expensive portable systems aimed at the backpacking/camping market. The D-cell requirement also seems to be limiting my options.

This is to be used as a stop-gap measure in the short term, and as an auxiliary or semi-portable secondary system once I upgrade the household to a more powerful permanent setup.

Anyway, I've searched quite a bit, and can't really find anything that would seem to do the job. If any of you has seen, heard of, or has experience with a similar system, I'd be happy to hear your responses.

Thanks in advance for your help!

racerford
08-28-2011, 07:39
Do you have a battery charger now for those sizes? Can it function off of 12VDC. Will it charge in the time mentioned with the proper inputs?

How big are you D-Cells? 10000mah? If so, and they are NiMH. That is 12 watt hours each. So the panel will have to produce that produce at at least 4 watts under you conditions plus and conversion losses. So at least a 10 watt panel, I would think.

So we need more information to answer the question.

kirgi08
08-28-2011, 12:47
I can't think of anything in your price range.'08.

cowboy1964
08-28-2011, 14:05
What do you need D-cells for? Maybe you should look for alternatives for that.

Bolster
08-28-2011, 15:15
Try this search (http://www.candlepowerforums.com/vb/search.php?searchid=582671) at CPF.

The big argument is whether or not you want a battery to mediate the charging. After mulling it over and reading, I'm in the "mediate with a battery" camp, myself. Don't like the start-stop of charging every time a cloud drifts by. OTOH, backpackers don't like to haul around a battery to mediate.

You pick.

PS: The "enlightened" rechargers I know use Eneloops, and the D-casings they sell to go around the AA batteries. So that way you're just recharging AAs. Remember AA and D have the same voltage output, it's just runtime (amp hours) that's different. So with a few more swapouts (and faster charges!) you CAN use AAs instead of your Ds. Some folks like to standardize this way...I like to, but I don't run many Ds anymore. "Legacy" technology mostly (ie, old stuff).

RED64CJ5
08-28-2011, 15:58
This is what I have/use that means most of your criteria:

http://www.amazon.com/Powerfilm-USB-AA-Solar-Charger/dp/B001RMBHMK/ref=sr_1_1?ie=UTF8&qid=1314568673&sr=8-1

Sam Spade
08-28-2011, 18:32
Goal Zero 7 Watt system. About $100.

http://www.goalzero.com/shop/p/106/

RWBlue
08-28-2011, 20:12
I looked at this before when I was looking into a portable full powered HAM solution, and came up wanting. Then again, I was looking for more power, but over a longer period of time.

I don't have enough data to know for sure, but this might work for your price range.....
http://www.batteryjunction.com/solarchargers.html
http://www.batteryjunction.com/v2pocounbach.html


Personally, I would want more/larger solar panel. I would also want one that can be left out in the rain, snow,....

DJ Niner
08-28-2011, 22:44
...

PS: The "enlightened" rechargers I know use Eneloops, and the D-casings they sell to go around the AA batteries. So that way you're just recharging AAs. Remember AA and D have the same voltage output, it's just runtime (amp hours) that's different. So with a few more swapouts (and faster charges!) you CAN use AAs instead of your Ds. Some folks like to standardize this way...I like to, but I don't run many Ds anymore. "Legacy" technology mostly (ie, old stuff).I think this should solve the problem nicely! Not sure how I missed seeing the D/AA sleeves. I'll have to run a few tests, but even if I have to change-out the sleeved AAs twice as often, I'll still come out way ahead due to the cost/logistics/ease-of-use (and my "D cell" problem is pretty much what you said; a few older devices that I don't want to do without or replace at this time).

A hearty "Thanks!" to all the folks who provided input and links!

Dirk Pitt
08-31-2011, 14:26
These seem to be over looked. I have been using these for some time in the garden and it hit me that each one of them is a AA battery charger. I jam ust using this link as an example there are all kinds of these things out there and they work good. I have mounted some of the heads to a board and point them at the sun, yes it is crude but it works and it is cheap. And you are hiding your power regenerating tools in plain site! They do come with a lousy chinese rechargeable battery, I just put a good one in and it works.

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&productId=202080420&langId=-1&catalogId=10053&MERCH=REC-_-search-3-_-NA-_-202080420-_-N&locStoreNum=6647

RWBlue
08-31-2011, 17:34
These seem to be over looked. I have been using these for some time in the garden and it hit me that each one of them is a AA battery charger. I jam ust using this link as an example there are all kinds of these things out there and they work good. I have mounted some of the heads to a board and point them at the sun, yes it is crude but it works and it is cheap. And you are hiding your power regenerating tools in plain site! They do come with a lousy chinese rechargeable battery, I just put a good one in and it works.

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&productId=202080420&langId=-1&catalogId=10053&MERCH=REC-_-search-3-_-NA-_-202080420-_-N&locStoreNum=6647

Yep, I have a few of those around the house. With the little LED, they glow most of the night.

DJ Niner
09-01-2011, 01:37
These seem to be over looked. I have been using these for some time in the garden and it hit me that each one of them is a AA battery charger. I jam ust using this link as an example there are all kinds of these things out there and they work good. I have mounted some of the heads to a board and point them at the sun, yes it is crude but it works and it is cheap. And you are hiding your power regenerating tools in plain site! They do come with a lousy chinese rechargeable battery, I just put a good one in and it works.

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&productId=202080420&langId=-1&catalogId=10053&MERCH=REC-_-search-3-_-NA-_-202080420-_-N&locStoreNum=6647I also have a (large) hand-full of similar lights; slightly older ones that actually take two AA cells instead of one. I bought them for camping and/or longer-term power outages, as they will provide a limited amount of dim-but-useful area lighting with little or no setup or maintenance. They can be charged outside and then brought inside at night, with one or more placed in each room to assist in nocturnal navigation. :cool:

The ones I have are not bright enough to read by, but plenty bright enough to get around the house or use the bathroom at O-dark-thirty. Keeps any children calm, removes the need for candles or other more hazardous options, and reduces the use of other higher-power choices like flashlights, which can be saved for more high-need/high-speed applications.

But if it's cloudy when charging, you won't get much out of them that night.