[k9srkool]

I want to know, if I connect four AA batteries together, and then connect the ends to the positive and negative terminals of a usb car charger, and then connect my iPhone 3G to the other end of the charger, will it properly charge my iPhone 3G? And if not, why not and what can I do to fix it?

Information on the car charger and the batteries:
The usb car charger was made for iPods, and the iPhone 3G can take a maximum of 5v dc current when charging.

I would be using four AA rechargeable NiMH (Nickel-Metal Hydride) batteries, each if which has 1.2V dc current and 2 amp-hours. The batteries also say "Standard charge 200mA for 16h," but I'm not sure what that means. They are the standard Duracell rechargeable batteries.

I believe that these four batteries will provide a total of 4.8v dc current, and usb cords use 5v dc current.

[one1]

Iphone Ipower: iPower Backup Battery for iPhone Has Built-in Speaker too

[k9srkool]

I know that I could buy that, but I want to make a diy charger, not buy one, plus it costs $44.

[one1]

You got 2 options, learn what you're doing and how to properly charge a 3 wire balanced Li-On battery, or buy that.

I gave you the only option that won't end in tragedy.

This is beyond ghetto.

[k9srkool]

I don't see any reason why it shouldn't work, I'm just wondering if there are any electricians here who can tell me if it won't work.

[Deviatorz]

Technically you can. You could splice the cable from the car port end and solder it to your batteries. However I would suggest you put a 5v regulator (7805 would work) between the battery and the charger itself.

What I would do is buy a usb cable with a female end, cut it and solder it to a 5v regulator and connect it (by soldering as well) to a 9v battery. There are plenty of these tutorials floating around. After that use the USB cable that came with the iphone and connect the male end to the female end, like you would when you charge your iphone regularly.

Look into your regulators. Find out what the max amp input of the iphone is and buy the regulator according to that (you don't want your iphone battery to blow up). Also my method isn't really efficient, as this method generates a lot of unwanted heat and you don't use the battery to the full extent. There are other chips floating around that make it a lot more efficient in terms or battery usage but might as well spend money on a battery charger for the iphone. I'm pretty sure there are tons of cheap battery iphone chargers floating around on ebay.

I'm not sure if my info is 100% correct (have been working with electronic components in high school only; I do a lot of extracurricular things in electronics =P) and do it at your own risk. I'm not holding any responsibility for your actions nor your outcomes, whether they be positive or negative. Do some research before plugging in batteries to your iphone and good luck.

[Chefanim]

Originally Posted by woknam66

I don't see any reason why it shouldn't work, I'm just wondering if there are any electricians here who can tell me if it won't work.

Seems you are new here.... you should listen to one1

[k9srkool]

Chefanim: one1 isn't making any sense, and just because I'm new here doesn't mean that I'm an idiot....I'm looking for someone who knows a lot about electricity who also owns an iPhone 3G....

one1: You're not making any sense.

Deviatorz: Thank you, but I really don't like soldering, and what I am contemplating doing doesn't require soldering and is fairly simple.

[kvizzel]

Hey man, if you aren't listening to anybody advice your SOL, your only option is to buy it.

Or wait, try it! Tell us when you break your iPhone.
Let me laugh.

[Chefanim]

one1 is the resident hardware guy here, he knows what he is talking about.

You say you are looking for someone who knows about electricity and owns a 3G, but you aren't listening to the best candidate here.

[Mes]

One thing is sure ........ you will find Apple hasn't made it easy to do what you're contemplating.... or anything for that matter. That's the whole reason behind the love/hate Apple relationship. You can jerry-rig something .... but even the simplest of battery kit solutions require some extra work (almost always soldering).

But give it a try .... and when it doesn't work, oops. We're not idiots either. Some of us have learned the hard way and really don't want that to happen to you.

[one1]

Originally Posted by woknam66

Chefanim: one1 isn't making any sense, and just because I'm new here doesn't mean that I'm an idiot....I'm looking for someone who knows a lot about electricity who also owns an iPhone 3G....

one1: You're not making any sense.

Deviatorz: Thank you, but I really don't like soldering, and what I am contemplating doing doesn't require soldering and is fairly simple.

It'll work fine, do it..... please have a friend with a video camera record the results.

[cricketlang]

Originally Posted by Chefanim

Seems you are new here.... you should listen to one1

hahahahaha for real. some people would just rather just do it themselves

[k9srkool]

Originally Posted by kvizzel

Hey man, if you aren't listening to anybody advice your SOL, your only option is to buy it.

Or wait, try it! Tell us when you break your iPhone.
Let me laugh.

I think that you are wrong.

Originally Posted by Chefanim

one1 is the resident hardware guy here, he knows what he is talking about.

You say you are looking for someone who knows about electricity and owns a 3G, but you aren't listening to the best candidate here.

I did not know that.

Originally Posted by Mes

One thing is sure ........ you will find Apple hasn't made it easy to do what you're contemplating.... or anything for that matter. That's the whole reason behind the love/hate Apple relationship. You can jerry-rig something .... but even the simplest of battery kit solutions require some extra work (almost always soldering).

But give it a try .... and when it doesn't work, oops. We're not idiots either. Some of us have learned the hard way and really don't want that to happen to you.

I still don't see why it wouldn't work, and nobody here has even TRIED to explain why. My logic is this: When the car charger is plugged into the car, dc power flows from the car, through the car charger, and into the iPhone. When the car charger is attached to batteries, dc power should flow from the batteries, through the car charger, and into the iPhone, right? If my logic is flawed, please tell me

Originally Posted by woknam66

why not and what can I do to fix it?

As I originally asked.

Originally Posted by one1

It'll work fine, do it..... please have a friend with a video camera record the results.

?!?!?

Originally Posted by cricketlang

hahahahaha for real. some people would just rather just do it themselves

Was that really necessary?

[Deviatorz]

@ Everyone

I think we should just help the guy. I mean, the Internet isn't a place we all like to put our trust on. Yes one1 is the best iphone hardware guy here but the guy still wants help. If on an essay you were required to show how to make something, you would most definitely fail the essay if you simply put, its not a good idea to make such a thing. One1 gave advice, woknam66 chose not to listen, so we should still help him accomplish his goal, whether the out come is good or not.

@ woknam66

I stated in my first sentence that "Technically you can.". Just make sure you wire (I guess you would have to strip and coil it on） it correctly to the charger. By that I mean MAKE sure that you coil it on to the iphone car charger before the adapter/regulator part. I don't know where the adapter/regulator is located on the charger, it could embedded in the end where you insert it into the car or it might be between two ends. Just make sure you coil it before it. If it is in the end where you insert your charger in, you will have to break it up and coil your batteries with wires in each terminal with the charger accordingly. If not then I think it would be ok make a cut before the adapter and match it with your batteries accordingly.

Also, it's best to find out what the output of a car (any car) is and put your battery in series + parallel to make it have a similar output as the car. Just because you have 5v volts with the battery doesn't mean it will have 5v come out the other end. The charger is made specifically for your car; in such a case, you won't have enough juice to charge your iphone if you series your battery into 5v.

Again I am not 100% sure if this will work. I helped out because I miss working in my high school electronics class. I take no responsibility for your actions and certainly not for your outcomes, whether they be good or not. I, as well, urge you to buy one from ebay. If this helped, please press the thank you button.