4 x AAA to power usb device ?

cbr

cbr

cbr

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Not sure if im posting this in the right place, sorry.

Im trying to make a battery pack (4x aaa rechargable batterys)
to power a small video camera that has its own internal battery, but that only lasts about 3 hours. normally charged from usb, and can use while on charge.

So i got to thinking if i make a battery pack with the 4 aaa batterys,
each battery has 1.2 volt, so in total 4.8 volts.

Although a multi meter reads them as 5.2 volt.

do any of you know if this would work ?
 
It could work. It depends on whether the camera can accept a "poor quality" power supply (i.e it's designed to work with power supplies that can't regulate voltage very well, like your batteries)
 
I have a powerchimp emergency charger I desperately bought at an airport once. Takes 2 AA batteries and can charge most devices with a USB connection.

Power output from their site says 5.5V 450mA max (It charges my iPhone 3GS fine and also charged a friends Archos media player fine too).

Might be worth looking at as they are quite cheap.
 
thanks for the replies so far :D

Just doing a few tests @ the minute.

how can two AA battery's give a total of 5.5 volt ??? :confused:

normal AA,s have a voltage of 1.5 volt
x2 gives a total of 3volt,

Well im no expert thats why im here asking lol

Will reply back soon once i check a few things
 
OK

I have tested several times, my fully chraged battery pack 4xAAA = 5.4 volts

The mains charger for the camera gives = 5.59 volts works

The usb lead for the camera, plugged into my usb port gives = 5.01 volts works

So why wont the battery pack not work ? its between the upper & lower volt level the camera can clearly work at

Any ideas
 
cant be 100% but think the little camera would be about 150ma
the internal battery that is crap, is 3.7 volt 620maH

though im not patching through to replace the internal battery, just trying to use a battery pack as a charger, if that makes sense !

the batterys im using are sanyo eneloop 800maH each x4 = 3200

Maybe this is my downfall,, I was going on the idea the camera would only draw what it needed .

enlighten me please
 
Just thought of this, even if it had of worked wont all the amps fry the internal battery :eek:
as i had planned on using this like a charger !!
 
cbr said:
how can two AA battery's give a total of 5.5 volt ??? :confused:

normal AA,s have a voltage of 1.5 volt
x2 gives a total of 3volt,
Click to expand...

These charging devices have a small circuit inside them (DC to DC converter/buck boost) which increases the voltage of the two batteries to give 5v output.

It would work with 4 x eneloops; however because there is no circuit to stabilise the voltage it will not be very efficient at all and as the battery voltages fall the device that you are charging will stop charging.

cbr said:
Just thought of this, even if it had of worked wont all the amps fry the internal battery :eek:
as i had planned on using this like a charger !!
Click to expand...

Do not worry about the mismatch with amps, volts is the most important thing here.

The figure of mAh (milliamp hour) is the capacity of the batteries that you have.

There aren't many decent devices around that take AA batteries and give USB output as said by vidda powerchimp is one of them. Most of these products tend to have their own internal non removable rechargeable battery.

Here is quite another popular one which can be ordered in kit form or pre-assembled: http://www.ladyada.net/make/mintyboost/
 
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cheers 2StepSteve that looks interesting.

I understand its not too stable but i thought it would have worked all the same.

Further testing. . . .
the mains adapter works as said before.

but after more checks the usb cable for the device does not work.

When I say it wont work, it does indeed charge, so does the battery pack i made.

what i mean by wont work is. . . the camera wont operate while charging like it does with the car charger and mains charger.

Im starting to think these work cuz there are pins (data pins) short in the cable so the device knows to operate as normal

instead of going in to usb mode.

Could I be on the right track
 
cbr said:
Im trying to make a battery pack (4x aaa rechargable batterys)
Click to expand...
I use one these to charge my USB devices when am out


http://www.ebay.co.uk/itm/DURACELL-...rElectronics_Batteries_SM&hash=item19c31f4dfb

CFf15wWkKGrHqZlIE1F3PZbojBNVToZPO3w_12.jpg


DSC00362.jpg
 
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sorry to hijack the thread a little but i have a question that may be relevant?

how important is the mah rating for a device? i have a device that i have to constantly buy power packs for that use 6 aa batteries (their own brand im guessing) that are rated ar 9v 2200mah. in that past i have made my own packs by soldering standard batteries in the same onfiguartion, but now im considering using a single 9v battery. will it work?
 
Jesus, just buy a decent camera.

azamc said:
sorry to hijack the thread a little but i have a question that may be relevant?

how important is the mah rating for a device? i have a device that i have to constantly buy power packs for that use 6 aa batteries (their own brand im guessing) that are rated ar 9v 2200mah. in that past i have made my own packs by soldering standard batteries in the same onfiguartion, but now im considering using a single 9v battery. will it work?
Click to expand...

mAh is the capacity of the battery, the higher the rating the longer it lasts. 6 AA batteries will last many times longer than a 9v battery which typically only have a capacity of 550mAh.
 
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who said it was'nt a decent camera !!

But would'nt matter what the device was, its the project im trying to do thats not very common.

no offence meant but do you even understand what im trying to do with it ?
 
yes thats right i could, and it be the same type it replaced! and therfore last just as long as the first.

But as i said it dont really matter what the device is at the end of the day
 
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