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ArcticMyst Security by Avery

Need help.

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Oct 24, 2009
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Okay my laptop finally kicked it last bucket.
It had a problem of its dc barrel jack coming off the board even when being super careful.
So all i would do is resolder it to the board.
But after doing it, it will still not work.
I can charge the battery in another pc and power it up just fine but i can no longer run it for long time the battery's only lasted 2 hours.
So my question is can i solder the power supply to the battery itself, now while saying that i know that this is not the best fix and it will need some sort of circuit so i dont over charge the battery but.
I have no more money left to pour into things like a new pc.
So what i am after is some circuit to let me over ride the laptops charging circuit and make the power supply into a fake battery.
Power supply; 19.2V 4.62 A
Battery ; 14.8V 6450 mAH capacity 96WH
But the battery has 9 terminals.
Here is a low quality video of my charger and battery.

With out this pc i am not going to be able to be online as much, i have to steal a friends pc to charge the battery then i have to hope it lasts before i can steal his...
 





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You mean solder the power adapter to the laptop's battery connector terminals, so it'd be like a wall-powered-through-battery-connector system?

I would say it's fine, but I'd drop the voltage down from the wall adapter to whatever the battery voltage rating is.
 
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I've come across several laptops with the DC power jack failing. My method is, wherever possible, to remove the silk-screen (green layer) from the PCB in the area surrounding the jack, and allow a large amount of solder to flow across the entire affected pad. This means that the connection is larger and would need more heat before becoming damaged. I've fixed several successfully with this method, and tried but failed on another laptop (connection was still not reliable enough).

Remove as much of the original cheap Dell solder as possible, and use some flux too. There are some that are too far broken to fix though, and you risk doing more damage. YMMV.
 
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it has been fixed 12 plus times and now it just wont work so i have a 1000$ laptop and cant use it.
That is what i was thinking but i dont want to release any smoke if you know what i mean.
Also the battery has lots of terminals around 9 is there any way to tell whats what or should i break open the battery even tho its still good.
 
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The battery has a chip inside which monitors temperatures, discharge rates, voltages etc, and feeds that information to the computer, and cuts power if the batteries are at risk of fire. That accounts for some of the pins. Also, those pins might provide access to each of the battery sets (inside are X batteries parallel, 4 batteries series) - so that might be what 5 of the remaining pins are?

Trying to charge directly without using the battery manager is not a good idea, and might be hard or dangerous. You could give it a go, but each of the pairs of parallel batteries is directly connected by welds to a nickel strip, which connects to the battery manager board. Charging without detaching might be hard, and re-attaching them (to make it usable in the computer again) is a pain and may be impossible without the right tools - soldering isn't the best way, and risks damaging the batteries, and in most cases doesn't even stick.

I'd try repairing the jack unless there really is no other way - can you get any macro photos of the PCB?

You could provide a pinout of that connector. Alternatively I think I have a dead battery similar to yours. What's the serial/model number of yours? I'll go check mine.

EDIT: mine is an U1223, 14.8V, 4300mAH. Part Number D2025.

EDIT 2: Cracked mine open - plenty of plastic clips but no screws. Force was used in opening ;)
8x 18650-sized batteries in there, with 2 temperature probes thermal-glued on to them. Attached to the battery casing by double-sided tapes, with 4 "blank" batteries (plastic tubes) at the edge to prevent rattling. Mine's 4 series, 2 parallel. Investigating further for you, may be a couple of hours since I have other stuff to do.

Edit 3: From left to right (orientation of battery as seen in vid thumbnail):

Gd,Gd,SC,SD,TS,BI,ID,B+,B+ according to the silk screen.

Don't ask me what SC,TD etc are yet, I'm not sure, but they're part of the battery control circuit. SC,SD, BI,ID have what looks like a current-limiting resistor so they're probably signal wires though.
 
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yes ours are the same i can use that model number.
Okay so what i want to know know is can i just say screw the battery and use those terminals to power the laptop?
I want to make this thing into my bench pc so it will not need to be portable. or have a battery.
I was told that i might need to do more than drop the voltage down but i am not even sure how to drop the voltage of a 6amp psu...
I also smoked the charging circuit so i am sure that whole route is dead.
 
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See my edits.

It would be possible (in theory) to essentially just hollow out the battery, and solder the appropriate power (14.8V,5A) to the correct connection points, and remove the li-ion batteries themselves, to make a non-portable "wall adaptor" that sends the power to the machien via the battery port and not DC jack. The issue is:

BIG PROBLEM: You might find that the machine refuses to start up without the battery manager attached (battery clones have this problem sometimes) so in that case you'd have to make a power supply that provides 4 3.7V lines to trick the battery manager into thinking that the batteries are fine?

Anyone got more experience than I do with this kind of battery hacking?

I don't have a lab-style PSU or I'd try it out myself for you. If you're desperate I might risk it with a regulated 12v line from a computer's PSU, but I'd rather not risk damaging my old but working laptop.

EDIT: Post 1500, 100 rep :)
 
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Well to make something to trick the logic circuitry wont be hard after i hollow out the battery.
Lets just say for the sake of my great luck (i dont have) i wont need to do this. i just need to reduce the V and attach it inside the battery.
To do this i need to drop the current how do i do that?
 
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my steam is up atm kiyoukans stream - Live Webcam with Free Chat


battery.jpg
 
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