Solar Battery Chargers

Hoolie · Post by **Hoolie** » Fri Jul 13, 2007 12:00 am

Can anyone recommend a good solar charger for AA batteries? It seems there are a lot of different kinds out there, but the specs are sometimes scarce (e.g. how long does it take to charge?) Also, I've seen a lot that charge 4 AA batteries. Are there any that charge 8 or more? I expect to be running through them pretty quick. I'm using one portable amp that uses 8 AA batteries. Also, I use a halogen bike light which quickly saps power from 4 AAs. Possibly also using AAs for el wire. I'd rather not buy a bunch of AAs in bulk and then throw them all away.

Also, I will probably need a way to recharge an ipod. I've seen one solar charger that is made for this purpose (the Solio), but it's pricey (85-100 bucks). Any cheaper alternatives out there?

Captain Goddammit · Post by **Captain Goddammit** » Fri Jul 13, 2007 3:28 am

Well, none of these suggestions are solar, but...
If you'll have your car/truck there, it's battery should have zero problem keeping an iPod charged and still fire up at the end of the week, although you could always bring jumper cables to be totally safe. It'll also easily handle having AA battery chargers plugged into it. You could start the motor for a little while every few days to be sure it stays full.
Small battery chargers draw so little current that if you end up with neighbors who have a generator, they're usually happy to let you plug in and charge up, so bring your home charger just in case.

gyre · Post by **gyre** » Fri Jul 13, 2007 1:48 pm

I agree with charging off a generator or your car.
I'm paying 40 cents each for duracell AAs, so not bad.
Can you wire a larger battery into your device?
D cells maybe or a gelpack?

I think you would need a panel and separate charger to do what you want in solar.
I would think $200 to $250.

What I do with cameras is bring a lot of rechargeables with me.

Post by **AntiM** » Fri Jul 13, 2007 2:10 pm

Well, if you're in Hushville, there's no gennies, and you can't run your car. We charge off a 12v deep cell which we hook to a solar panel during the day(13w but I'm not certain without looking, no, it's buried in the lightbox in the garage.) Never paid attention to the timing on charging four AAs, less than an hour or so though.

gyre · Post by **gyre** » Fri Jul 13, 2007 2:40 pm

Charging time varies.
If you use the cheap chargers, the only smart charger is the ac only one from duracell.
Some of the others are 12 volt compatible, but not smart chargers.
Some pro chargers will work on many different batteries.

Lithium rechargeable batteries would be the best to use.

Post by **AntiM** » Fri Jul 13, 2007 2:55 pm

We have an inverter and alligator clips, stuff from the truckstop.

EspressoDude · Post by **EspressoDude** » Fri Jul 13, 2007 3:14 pm

Another possibility is to get a "standard" 12 volt solar panel to charge up a 12volt deep cycle battery, then run a 12volt dc to 120vac inverter (50 - 100watt cheapo). Then you can plug a regular 4hour lithium or ? battery recharger into the outlet.

gyre · Post by **gyre** » Fri Jul 13, 2007 3:23 pm

I found this.

http://www.icpsolar.com/4105/system_setup.asp

I found some AA and universal chargers for about $30.
They should all state charging time at full power.

A full size battery is about 3000 mah so you can estimate from the output of the solar panel.

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 10:29 am

Thanks for the replies everybody.

Some of these comments are onto something I was already considering, but I really didn't know how to go about it. That is, getting a larger solar panel and using it to power a standard AC outlet. This is intriguing since I think it would open up other power possibilities for me besides just charging batteries (lighting my shade structure for example). I really don't like the idea of using a gasoline powered generator.

The other thing that occurred to me is the limitations of my ipod. It's an older model and the battery is good for only about 4 hours. But I could pick up a 2GB ipod nano for about $100. The battery life on these is around 20-24 hours. So, it wouldn't need the constant charging my current ipod would require, and I could give it a charge off the car mid-week. I think I'd rather do this than shell out that $100 for a Solio.

Still, I'm intrigued with the idea of a basic solar setup utilizing the 12 volt battery. Is there a good online source for ordering such things?

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 11:29 am

gyre wrote:Can you wire a larger battery into your device?

Now this may be a possibility. I don't have the amp yet (it's being shipped), but I found out it has a DC 12V input. Photo here:

http://www.audio-ideas.com/reviews/powe ... p-rear.jpg

It seems conceivable that I could use this input to wire it to a 12 volt battery. Is there an available connector that would work or would I have to make one?

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 11:49 am

Captain Goddammit wrote:Well, none of these suggestions are solar, but...
If you'll have your car/truck there, it's battery should have zero problem keeping an iPod charged and still fire up at the end of the week, although you could always bring jumper cables to be totally safe. It'll also easily handle having AA battery chargers plugged into it. You could start the motor for a little while every few days to be sure it stays full.

Ah, here's a variation on this idea. I think this can be a cheap solar solution by getting one of these:

http://www.harborfreight.com/cpi/ctaf/d ... mber=44768

So, I could charge my batteries using car chargers, and then plug this thing in to retain the charge on the car battery, no?

gyre · Post by **gyre** » Sat Jul 14, 2007 12:16 pm

The plug for the amp should be readily available at a good electronics supply house.
They may be available made up but are generally made for each use.
Good quality cigar lighter sockets and plugs are available too in marine grade from Marinco and others.
Be certain the wiring is correct for your devices.
Bhphoto is a good source for adapters made up.

Any solar panel can be set up for charging a car battery.
I don't think the small one will do much though.

I found bulk prices on AA nicads and nimh.
I would use quantity rather than solar for such a short term use unless you have other uses for the solar setup.

You have a lot of choices for the amp.
You could make a battery pack of D cells and use Lithium ion, nimh or nicad or alkaline.
Or you could use a small 12 volt battery like a gel pack.
Do you know the power consumption?

Again, be very sure of polarity when plugging in any device.
All should be polarity protected, but many are not.
Most are a standard configuration, but not all.

I recently bought a few boxes of duracell alkalines for the summer.
I think I paid 75 cents for D cells and 35 cents for AAs and a little more for AAAs.

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 1:19 pm

The amp is the Sonic Impact T-Amp. I'm using it to make a small, portable sound system. I'm having trouble finding more detailed tech specs for the amp other than these:

# Technology: Trichip TA2024 IC
# Amplifier type: 10 watts RMS x 2 max into 8 ohms, 15 watts RMS x 2 max into 4 ohms
# Capacitor: 330uf
# Inputs: One stereo RCA to 3.5mm minijack, one power adapter
# Power source: 12V DC, 2000mA adapter (not included) or eight AA batteries (not included)
# Height: 3"
# Length: 7"
# Weight: .6 lbs

It will power two speakers, the labels on the back say:

Maximum Power 20W
Impedance 8

My only concern is battery life, and I have found some comments on the web about a limitation here with the 8 AAs. So, I'm looking for a solution.

gyre · Post by **gyre** » Sat Jul 14, 2007 1:46 pm

This review has the distortion specs for the chip itself.
It is 5 watts at 8 ohms and 9 watts at 4 ohms.

http://www.6moons.com/audioreviews/sonicimpact/t.html

The power supply you mentioned is 24 watts at 12 volts but the amp may handle more if the supply is under sized.
8 AAs does come to 12 volts exactly.
Nimh and nicad put out less voltage than alkalines and will reduce output somewhat.
As usual, the efficiency of your speakers is crucial.
The less power you use, the less power the amp will draw.

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 3:33 pm

Yeah, I'm trying to build this with as many materials I have on hand as possible. The speakers are from a small Pioneer stereo system with a broken CD player and other problems. The speakers themselves work fine, but I don't know how power efficient they are. Thanks for your input on this gyre. Once I get this project completed, I will try to remember to post some pics here.

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 3:52 pm

Another idea that occurred to me...

For my desktop computer, I have a UPS exactly like this one:

http://www.buy.com/prod/tripp-lite-bc-p ... 32447.html

It seems to me I could bring this along fully charged, and then use it to charge the ipod or rechargeable AAs. I would imagine it holds enough power for this??

gyre · Post by **gyre** » Sat Jul 14, 2007 4:10 pm

You can connect some speakers with a known rating and compare.
If they are drastically inefficient, it may be worth changing.
Efficient speakers are not all expensive.

Be very careful to keep the amp as cool as possible.
Use a shade cover for it if needed.
Just because the chip is rated for a certain wattage does not mean the unit will support it.
Direct sunlight will reduce the power it can shed.

gyre · Post by **gyre** » Sat Jul 14, 2007 4:19 pm

Depending on condition, the tripplite should work.
I would think it would be better to try not to drain it fully.
You could call tripplite and ask.
A few small things should not be a problem though.

Hoolie · Post by **Hoolie** » Sat Jul 14, 2007 5:01 pm

Cool. I will look into speaker efficiency.

The amp will actually be inside a box simply as a place to carry it, but also to protect it (hopefully) from sun and playa dust. The speakers, however, will be getting a severe dose of dust. I am planning on installing the speaker covers, but I know the dust will get right through them.

I think I will runs some tests charging with the tripplite here at home.

gyre · Post by **gyre** » Sat Jul 14, 2007 5:17 pm

A box should shield it from the sun, but take care it doesn't hold it more heat than is outside.
You can bag the speakers in thin plastic with little problem.

unjonharley · Post by **unjonharley** » Sat Jul 14, 2007 7:20 pm

I have run computer speakers for 4years now.. They call for 9v but I stick 12v to them.. They have a little amp built in.. I use the 12v batery pack from a drill.. Keep it charged with two solor panels about the size of a paperback book..This year I'm getting some of my recharge power from spinning the drill motor from the bicycle wheel.. In years past I have used current reducers from 12v to 4.5v and 9v.. You lose 40% battery to resistance.. Not a good show.. For the 4.5v to run the disc player I had the battery place weld up a pack of 4 rechargable.. Then I'm adding two more of the solor panels mentioned above.. ((Harbor Frieght)) 14$ per.. Also this year I'm adding in a boom box.. Go to weld up 8 D cell rechargables and keep them pumped with the drill/gennerator.. In past years I used a solor powered radio to amp instead of the boom box.. There was a small transmitter to feed the sound to the radio.. The whole thing was a big mess of wires but a lot of fun to screw around with..
OK to clean the whole mess up: Sound will start from a disc player or Ipod type.. the disc payer will be powered with 4AA rechargables sodered togeather with two solor panels in line set at 4.5v... In the case of the Ipod, a single AAA will run 7-8 hours.. bought 24 of them..

Then the boom boxset up: Sound will be feed by direct wire.. The boom box will be powered with 8 D cells sodered togeather (9v).. Hope to aford two 5 watt 12v solor panels to keep up the charge.. standby is 12v batery with reducer..

Then the speakers. they will be powered by the drill motor gennerator feeding through the charge port of the drills battery pack..

Are we having fun yet¿¿

Tiahaar · Post by **Tiahaar** » Sat Jul 14, 2007 8:58 pm

Unjon! That is a great concoction of power wiring you are putting together heheh I'll have to keep a fire extingisher handy when you come by in case your battery pacs are smokin. I'm trying to get away from running any lights from an inverter and do direct DC. Found out the main bus inverter draws 25 watts just idling so I'm getting a couple of the tiny 325 watt rated inverters (with tiny idle power) for AC stuff and leaving the big guy off most of the time.

unjonharley · Post by **unjonharley** » Sat Jul 14, 2007 9:29 pm

Tiahaar wrote:Unjon! That is a great concoction of power wiring you are putting together heheh I'll have to keep a fire extingisher handy when you come by in case your battery pacs are smokin. I'm trying to get away from running any lights from an inverter and do direct DC. Found out the main bus inverter draws 25 watts just idling so I'm getting a couple of the tiny 325 watt rated inverters (with tiny idle power) for AC stuff and leaving the big guy off most of the time.

YOu just never took a good look at the trike, platform.. Scares me

Ripped the big inverter out of my mobil.. Saves 15$ a month.. Installed a battrey charger.. It keeps up fine.. Converted some stuff to 12v. Like the monator and one tv.. put in a car radio/disc player for sound through out.. Stayed 120v compact for over head lights.. Moving to another location this fall.. Some solor panels and windmill will fit in very well.. Have part of a cupola set a side already.. That should hold the whole powe station..

I have three inverters 75w 350w 800w.. 75 from the van battery for the razor on camera.. 350 if I need to charge AA orAAA over night.. have never hookup the 800

Question?? Will I burn the 9v boom box if it hit the 8 D cell rechargables with 12v..

ibdave · Post by **ibdave** » Sat Jul 14, 2007 11:34 pm

Ok, here is my question.

I want to run my grey water sump pump using a solar panel this year. I think it draws 1.5-2.0 amps 12v I have not found any amp listing on the smaller panels.. Also if the unit puts out more amps than being drawn will it burn out the sump pump. Last year I had it hooked to a car battery, but had to use the car charger hook to the honda gennie. The grey water evap set up really only works during the daytime bla bla blaaa. you get the point.. Thanks

gyre · Post by **gyre** » Sun Jul 15, 2007 12:32 am

unjonharley wrote:
Tiahaar wrote:Unjon! That is a great concoction of power wiring you are putting together heheh I'll have to keep a fire extingisher handy when you come by in case your battery pacs are smokin. I'm trying to get away from running any lights from an inverter and do direct DC. Found out the main bus inverter draws 25 watts just idling so I'm getting a couple of the tiny 325 watt rated inverters (with tiny idle power) for AC stuff and leaving the big guy off most of the time.

YOu just never took a good look at the trike, platform.. Scares me

Ripped the big inverter out of my mobil.. Saves 15$ a month.. Installed a battrey charger.. It keeps up fine.. Converted some stuff to 12v. Like the monator and one tv.. put in a car radio/disc player for sound through out.. Stayed 120v compact for over head lights.. Moving to another location this fall.. Some solor panels and windmill will fit in very well.. Have part of a cupola set a side already.. That should hold the whole powe station..

I have three inverters 75w 350w 800w.. 75 from the van battery for the razor on camera.. 350 if I need to charge AA orAAA over night.. have never hookup the 800

Question?? Will I burn the 9v boom box if it hit the 8 D cell rechargables with 12v..

Unjon, you qualify to be a Pogo character.
8 nimh or nicad should be putting out 9.6 volts, so maybe.
I presume you are talking about while the pack is connected to the boom box?
I would think the batteries would tolerate it, but can't say for sure.

How did you save money every month by taking out the inverter?

My trailer just came with a battery charger/12 volt converter.
Inverters do vary a lot in efficiency.
Some big ones are very efficient.

I can help you convert your lights to 12 volt fluorescent if you want to.

gyre · Post by **gyre** » Sun Jul 15, 2007 12:46 am

ibdave wrote:Ok, here is my question.

I want to run my grey water sump pump using a solar panel this year. I think it draws 1.5-2.0 amps 12v I have not found any amp listing on the smaller panels.. Also if the unit puts out more amps than being drawn will it burn out the sump pump. Last year I had it hooked to a car battery, but had to use the car charger hook to the honda gennie. The grey water evap set up really only works during the daytime bla bla blaaa. you get the point.. Thanks

I saw one portable charger rated at 160 ma.
2 amps is 24 watts at 12 volts.
Most small ones will be below one watt.
One of the first systems I helped someone with was a water pump for a barn and it worked okay, so it can be done.
As long as the voltage is regulated, the device won't draw more power than it needs.
Charge controllers are usually in place for batteries though.

unjonharley · Post by **unjonharley** » Sun Jul 15, 2007 5:58 am

ibdave wrote:Ok, here is my question.

I want to run my grey water sump pump using a solar panel this year. I think it draws 1.5-2.0 amps 12v I have not found any amp listing on the smaller panels.. Also if the unit puts out more amps than being drawn will it burn out the sump pump. Last year I had it hooked to a car battery, but had to use the car charger hook to the honda gennie. The grey water evap set up really only works during the daytime bla bla blaaa. you get the point.. Thanks

\/
Just put a battery between the pump and solor panels..That is a place i would use a 12v drill batery and conect the panel through the charge port..

unjonharley · Post by **unjonharley** » Sun Jul 15, 2007 6:23 am

gyre wrote:
Unjon, you qualify to be a Pogo character.
8 nimh or nicad should be putting out 9.6 volts, so maybe.
I presume you are talking about while the pack is connected to the boom box?
I would think the batteries would tolerate it, but can't say for sure.

How did you save money every month by taking out the inverter?

My trailer just came with a battery charger/12 volt converter.
Inverters do vary a lot in efficiency.
Some big ones are very efficient.

I can help you convert your lights to 12 volt fluorescent if you want to.

\/
The mobiles converter go's into a loop when the storage battreies are full.. It eat a lot of ac watts in the loop.. A battery charger drop down and off..

There is neg value in going 12v fluoresent from 120ac.. The mobile has 12v feed through out it.. I,m running 120ac 9&18 watt compacts for over head lights.. For bright light there is a compact spot light with a dmmer switch..After I move this fall.. If the wind blows and the sun shines I will use the free 12volt lights.. Converting the kitchen to 1930s 40s including a gas light.. It's cheap to run in the winter for light and that little heat.. I slipped a tiny fan in behind it.. I want to build a sawdust filled ice box and put a heat exchanger in.. Like the one for travel.. It will cost in ac if the free sun and wind is not putting out.. Our family runs a freezer for all..So I could sub it with block ice part time..

gyre · Post by **gyre** » Sun Jul 15, 2007 1:59 pm

I'm a little confused.
All the wiring in my trailer is 12 volts for lighting.
If you are on the grid all the time, ac is fine, but I thought you ran on 12 volts some of the time?
I'm trying to decide whether to get a good inverter or just get 12 volt ballasts.
There are some advantages to the 12 volt units in terms of flexibility besides efficiency.

If you are using ac, you might want to upgrade to some of the more efficient types such as PL-S or the T-8s in use now.
Ballast of that type have come down a lot.
I plan on using those for bounce lighting in my trailer.

unjonharley · Post by **unjonharley** » Sun Jul 15, 2007 2:26 pm

Yes, I have retired into a 5th wheel which I am remodeling to the 1930s 40s style.. Cept the loft/bedarea.. Going for altra modern there.. The ligting is 12v.. But being on line all the time I have went to hanging light fixture.. For these I have the new conpact bulbs.. Also a couple of naked bulbs.. For these I have cripton.. MOstly for show.. They give about 25w lite.. Have gas lights insalled already.. I have left the 12v in place.. Later this year they will be powered by 12v wind and solor as will my refigerator..