Originally Posted by Motorolalover

Its 2460/2530 mAh. I wonder what does that mean.. does it mean its in between this?

"2460/2530 mAh (min/typ)" ... i take that to mean:

2460 mAh = minimum (guaranteed by the manufacturing process and/or quality assurance testing)
2530 mAh = typical (most batteries will have this amount)

What's interesting is the "9.3/10Wh (min/typ)", which has double the tolerance (7%) as the mAh (2.8%)

2460 mAh @ 3.8v = 9.3Wh
2530 mAh @ 3.8v = 9.6Wh

So I suspect that the package, for whatever reason, overstates the "typical" Wh slightly.

Thanks! I was waiting for a teardown to give me an idea of how repairable it is. I will probably get one soon...

One thing tho: Is the screen fused with the front glass? Is it also fused with the carcass? (meaning that if it breaks of the touch stops you have to replace the WHOLE front assembly)

I believe all AMOLED displays works that way, but it doesn't hurt to ask...

I wonder if we had a vzw maxx HD if we could just slap the back onto the xt925, battery and all so I would't have to pry all the electronics off the maxx back just to use it?

@grant2 excellent work dude. thanks a lot.

You said ask for pictures if you need... here is mine..

can you take few more pictures of the back cover under the battery.

I am trying to figure out if i can squeeze an Qi or powermat receiver in there, maybe with some bulging... but not sure about the NFC and etc around the area.

cheers

Originally Posted by amedeh123

One thing tho: Is the screen fused with the front glass? Is it also fused with the carcass? (meaning that if it breaks of the touch stops you have to replace the WHOLE front assembly)

YES the display appears to be plastic-welded to the bezel! There is no obvious way to separate them. (see pics in main post)

I cannot determine if the glass is fused with display or not.

Originally Posted by nippit

I am trying to figure out if i can squeeze an Qi or powermat receiver in there, maybe with some bulging... but not sure about the NFC and etc around the area.

New pictures in the main post! Unfortunately I'm not sure they can give you the info you want...

007shark talks about putting a magnet on the cover in this post: http://forum.xda-developers.com/show...3&postcount=17 so clearly there is room to put more in there.

The cover is already shaped thicker at the top, which is where the NFC is glued, so the battery tray is actually flat.

I don't think there is room for something about as thick as a credit card. The case can flex a bit, but only in the middle, so anything thicker than a credit card would have to be a decent amount smaller than the battery tray (which is 105mm x 58mm) for the flexing to give more room.

I could only find a picture of a Qi receiver for the Galaxy S3. If the pad you are thinking of using is the same dimensions as that, I expect it to fit. However, getting power to the battery is another issue. The EV30 battery plug has 4 pins and they fit snugly into the PCB. You can't really attach there.

It seems much more plausible to solder the receiver to the battery's electronics at the same place as its plug is soldered. You would need to use your voltmeter to identify which of the solder points actually connect to the + and - terminals on the battery. (See picture in 1st post). Once you've soldered the wires you can attach the receiver to the battery with the double-sided tape that's already on the battery.

If you attempt an install, please let us know how it goes.! This sounds like a great mod.

Edit: I tried to reassemble phone with a credit card between battery & PCB. It was still too thick. I would guess you could fit approx. 1/2 credit card thickness, or approx. 0.35mm. However if you include the potential flex from the back cover this receiver probably could still fit.

Originally Posted by grant2

"2460/2530 mAh (min/typ)" ... i take that to mean:

2460 mAh = minimum (guaranteed by the manufacturing process and/or quality assurance testing)
2530 mAh = typical (most batteries will have this amount)

What's interesting is the "9.3/10Wh (min/typ)", which has double the tolerance (7%) as the mAh (2.8%)

2460 mAh @ 3.8v = 9.3Wh
2530 mAh @ 3.8v = 9.6Wh

So I suspect that the package, for whatever reason, overstates the "typical" Wh slightly.

Actually not weird for the tolerance.
The voltage probably has some tolerance. So P=IR.
That is Power is equal to Voltage times Current.
So 2.460x3.8v = 9.4Wh
If we back into the number then we will assume 3.8V is the minimum voltage from the battery based on the specs.
Then that means you could have a voltage as high as 3.95 from the battery based on 10Wh.

The bottom line is that to get to 10Wh either the voltage or current capacity has to go up.

Originally Posted by tech_head

Actually not weird for the tolerance.
The voltage probably has some tolerance. So P=IR.
That is Power is equal to Voltage times Current.
So 2.460x3.8v = 9.4Wh
If we back into the number then we will assume 3.8V is the minimum voltage from the battery based on the specs.
Then that means you could have a voltage as high as 3.95 from the battery based on 10Wh.

The bottom line is that to get to 10Wh either the voltage or current capacity has to go up.

2.46ah x 3.8v = 9.348Wh. So I think you are rounding the wrong way.

I considered that variable voltage may be responsible for the discrepancy, and although there was some merit, I wasn't really convinced.

My EV30 battery has a voltage range of 3.51v -> 4.33v during discharge. This would produce an average voltage of 3.92v, assuming an even slope. If the slope were convex (i.e., voltage drops more slowly at higher voltages) the average could indeed be 3.95v.

The problems I have with the idea is:

1) voltage is controlled by the onboard electronics. Others might tell me if this isn't the case, but every EV30 battery should have _exactly_ the same voltage range (determined by controlling electronics), even if the capacities vary (determined by electrode materials). Therefore voltage cannot contribute to the delta between "min" and "typ" batteries.

2) why would the "min" Wh be calculated from 1 arbitrary voltage level (the one displayed on the label) and the "typ" be calculated from some other arbitrary voltage level (3.95v) that's not listed anywhere?

...
an interesting academic discussion, and perhaps one day someone in the battery manufacturing industry can confirm exactly how the numbers on the label were derived?

Originally Posted by grant2

YES the display appears to be plastic-welded to the bezel! There is no obvious way to separate them. (see pics in main post)

I cannot determine if the glass is fused with display or not.

Damn! I was hoping to remove the sand and crap that's stuck inbetween the bezel and screen!

Anyway, nice teardown! Thanks so much for taking the time and posting.

asd

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i love my phone