| T O P I C R E V I E W |
| galeforce |
Posted - 31/12/2007 : 12:29:07
Has anyone come up with a solution for a AA battery charger, I have a few panels from garden solar lights and wanted to put them to use, so if anyone has done this out there please share your thoughts with us. I know ben did this with his radio, but I just want to charge batterys AA.
Reduce your C02, go Green. |
| 8 L A T E S T R E P L I E S (Newest First) |
| Peter Williams |
Posted - 04/01/2008 : 15:25:10
Is it possible to use the light sensitive switch on these panels on other applications.
I have a night light for my little girl made from ultra bright leds run from 4 aa batteries charged by a 6v solar panel. I have to switch it on and off as required but would prefer not to.
Are these light sensitive switches made for a specific voltage or will they work with 4.8v, 6v, 12v blah blah blah??
Peter |
| ghurd |
Posted - 03/01/2008 : 15:49:59
If the battery voltage will not be checked often, it might be a nice idea to add some kind of "charge controller".
Series two 1N4001 diodes, put them in parallel with each cell. Cheap & simple. 2 series diodes will begin to pass small amounts of current around the battery when the battery gets to about 1.25V, and most of the current will bypass the battery before 1.4V.
I'm told it is fairly effective for small charging currents like yard light panels put out. No idea how to post a sketch of it.
A friend who knows a lot about ni-cds told me to try to keep them about 1.35V unless using a quality smart charger.
G-
|
| nobicus |
Posted - 31/12/2007 : 18:17:56
If 'galefore' is like me he has the whole set of 10 lights rotted through (bought 2 years ago cheap at B&Q).
You have joined two panels together to charge two batteries. I have left the panels as they are and have two panels charging two batteries. The only difference between me and you is that you have had to acquire a "two battery" holder and do some soldering. I have just attacked the lights with pliars and screwdriver just to reduce the size so that more fit onto the windowsill.
As most pieces of kit use four batteries would it be best to solder together four panels and use a "four battery" holder so that one would get an even charge on all the batteries?
I think I has better write my "newbie" details so that you folk know what I am trying to achieve with my "stuff"
|
| gotwind |
Posted - 31/12/2007 : 17:53:08
Yes Nobicus,
One panel would work fine, It was just that 'galeforce' had more than one available, I suggested using two together, connected in parallel for more power.
The light sensing switch is not an issue, because the panel is removed from the garden lamp ideally.
An idea of what I mean here.
http://www.gotwind.org/DIY_Solar_Powered_Radio.htm
The Futures Green - Getwind of it. |
| nobicus |
Posted - 31/12/2007 : 17:08:29
Wouldn't it work to have just one panel and use the battery holder that is inside the light? I have a number of these where the legs of the LED have rusted through because the lights were not waterproof. It would be easy to just line them up along the windowsill or would the light sensing switch that turns the LED on and off interfere? |
| galeforce |
Posted - 31/12/2007 : 15:00:19
Hi Peter,
Tried windstuff but looks like they no longer sell them. So I have come up with the idea below for the time being, I will clean it up when I get chance, but each battery gets 1.5v on a cloudy day.
Reduce your C02, go Green. |
| Peter Williams |
Posted - 31/12/2007 : 14:17:12
When the suns not out to play try Windstuff who used to sell a small educational savonius for charging aa batteries, I've got one but haven't build it up yet.
I'm undecided whether to try to attach the generator to a "tin can" stirling engine I'm making and run it off veggie oil. Or use the small motor from a broken hand winding touch type thingymebob.
Peter |
| gotwind |
Posted - 31/12/2007 : 13:11:10
Just connect the 4 volt garden solar panel to 2 AA cells using a blocking diode IN4001 would work o.k
You could connect panels together(in paralel) for more power.
The maximum charging current suggested is 1/10th of the rechargeable battery's storage rating.
e.g using 2000mAh battery's the max safe current would be 200 mA - Therefore no more than two of those little 80-100 mA panels to be safe.
There are loads of those garden lights lying around - You could probably build up your own 12v panel with enough. 20v/4 = 5 panels in series.
|
