Fifth generation of iPhone. Repair of this device is straightforward, and requires screwdrivers, prying tools, and patience. GSM/CDMA / 16, 32, or 64 GB / Black or White.

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Direct charging of battery bypassing internal circuit

This picture says most of it:

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I want to connect a li-ion battery charger directly to the 4S battery, without removing it from the phone. This white plug shown touches the back of the pins 1 and 4 on the battery connector.

Will this work, or is the path of least resistance away from the battery, which could result in a short circuit? I'm currently looking at the schematics to try and make up my mind about this.

(I do this because there is something broken in the phone's internal charging circuit that I have been unable to solve. And yes, that red sticker is a good clue :))

Update

Here is the full setup. I kept the phone on while attempting, and I can confirm that it works. I have so far tested charging the phone from 10% to 30%.

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This phone does not charge through the charging cable. I kept it in anyway because the phone does notice it being plugged in. I haven't yet tested leaving it unplugged while charging.

The white plug is simply two small jumper wires with a third empty jumper head (just the plastic) between them. The distance turned out to match perfectly with the pins on the battery connector. I taped all of this together with electrical tape, then also taped most of the pins so they wouldn't touch any other metal surface in the iPhone.

Those jumper wires are simply connected to the + and - terminals of a 4.2V/800mA battery charger, which has all of the important safety components.

I was also lucky to find a plastic piece that allowed me to strap the plug at just the right angle.

With this, I can keep using the water-damaged logic board and charge the battery without removing it every time.

Answered! View the answer I have this problem too

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Having thought about this, the worst thing that should happen is that I will power the phone instead of charging the battery. Does that make sense?

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Yes, that will work as long as you realize that there will be no signal going to the charger to prevent over charging etc

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Thank you for the quick reply, oldturkey03! The charger I use, a Hähnel Ultima II for charging camera batteries, stops before overcharging a removed 4S battery. I was guessing it did so by measuring the voltage, and it stops before the battery is completely full. Shouldn't it do so also if the battery is in the iPhone?

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Can this make my iphone explose

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steven shad not your phone, just your battery:-) REad through the comments and answers you'll see that this was addressed. You have to prevent overcharging the battery whenever you modify this circuit.

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I can confirm that this will work for you... I've done it before when I was in a pinch and didn't have the right charging cable. I just split open a USB cable and hooked the red to positive and black to negative on the battery... it will charge just fine.

Only issue is it may not stop charging on it's own (it could pop and spray ion acid if it overheats from overcharging. Lithium ion batteries are extremely flammable, and also very toxic if it burns. So just be careful.

Major props to you though for getting it to work, I love your setup with the breadboard and the LEDs.

Another suggestion (if you have another iPhone... I have a lot cause I work on them), but you could get two batteries and switch them out to a working phone when it needs to be charged. You could also use two batteries and hook one to your charging system, so you can use your phone while the other battery charges. Just keep the screws off your iPhone and switch batteries. (The batteries are like $5 on eBay).

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Thanks for your reply! That is actually exactly what I am doing (swapping between two batteries). I actually prefer that over this direct charging method, since this makes the phone "busy". The charger I use is designed to prevent overcharging, though it doesn't charge as well as the iPhone would. And I have to admit that the LEDs are not used for now, I only store them on the breadboard, while the charger has its own LED indicator.

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