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	Raimu	2012-09-05 , 18:34
	Posts: 139 \| Thanked: 181 times \| Joined on Nov 2011 @ Oulu, Finland	#11

Holy ****, the look of that thing! You have my commendations.

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	Estel	2012-09-06 , 11:13
	Posts: 5,028 \| Thanked: 8,613 times \| Joined on Mar 2011	#12

Originally Posted by Fallingwater

What's the proper procedure? Do I go to the security people and say "look, I've got this battery I have to carry with me, but I need you to see it now so you don't think it's something entirely different"?

No freakin' idea, never did it. Your idea sounds good - I would ever check it few days before travel, contacting airport officials (maybe electronically, via mail with photo?), just to be sure, that I won't be forced to leave it behind on airport.

Originally Posted by Fallingwater

I doubt there's such a thing as a genuine 3.8Ah 18650. Last I heard the big guys (Sanyo, I think) had just barely managed to make one that held 3Ah, and even that wasn't being sold in great numbers; I'd be surprised if a 3.8Ah 18650 could even be made with consumer-level technology.

Hm, I always mistake phillips with panasonic, I mean the latter, in fact. Do you think that brand like them would cheat on capacity? In my country, it's possible to buy 3100 mAh version quite easily, locally.

I think I need to do own tests, as soon as I'll have backcover big enough to put them inside. BTW, in Your case, You use 3 18650's, so it would be 9,3 Ah. Even if they don't keep capacity to single mAh, it's a gain of 1/3 power draw frome each cell - realistically, I would expect 9Ah of practical power. If cells are not totally, completely fake, that is.

Originally Posted by Fallingwater

I like the idea of a proper body, and if I had a 3D printer I might try to make one, but as it is I'll just slap a square of plastic on the whole thing and call it a day. I just want something else than the bare cells to act as a contact surface and bear possible impacts.

I'm doing the opposite thing - milling it from piece of aluminum

Also to be found in my signature. Although, no way of putting 3 inside - 2 is absolute max, which proves enough problems as is, to fit it inside.
Bonus - it's barely thicker than Mugen cover. Something between 2 and 3 mm. For 6000 mAh capacity, it's a instant deal for me

/Estel

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N900's aluminum backcover / body replacement
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Measure battery's real capacity on-device
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vi_	2012-09-06 , 13:58
Posts: 1,680 \| Thanked: 3,685 times \| Joined on Jan 2011	#13

Originally Posted by Estel

...it's possible to buy 3100 mAh version quite easily, locally....

Highly doubtful...

__________________

N900: One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.

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Fallingwater	2012-09-07 , 09:59
Posts: 80 \| Thanked: 79 times \| Joined on May 2012 @ Northern Italy	#14

Originally Posted by Estel

No freakin' idea, never did it. Your idea sounds good - I would ever check it few days before travel, contacting airport officials (maybe electronically, via mail with photo?), just to be sure, that I won't be forced to leave it behind on airport.

That's a good idea.
Heh, I can visualize me going through the airport with my own security escort :P

Hm, I always mistake phillips with panasonic, I mean the latter, in fact. Do you think that brand like them would cheat on capacity? In my country, it's possible to buy 3100 mAh version quite easily, locally.

What is your country?

Panasonic probably wouldn't lie, but you have no guarantee that the cells have been made by them. The ones you can find locally are probably Chinese fakes with "Panasonic" printed on them, especially if they're cheap. Genuine 3.1Ah 18650 are quite expensive; I've had a look, and I can't find them for less than 12 euro each shipped from European sellers. They are cheaper from Hong Kong (about €8 each), but the fake risk is higher.

2.9Ah Panasonics are considerably less expensive (€8 locally), which would make them a more sensible buy, though still not cheap.

As for 3.8Ah ones, the fact that none of the places I know returns anything other than Chinese brand names (the various WhateverFires) when searching for them says a lot. I'm quite sure no 3.8Ah 18650 cell actually exists on the consumer market, and I'll bet a small amount of money any you manage to buy will give you a lot less capacity than stated, whether it has "Panasonic" written on its side or not.

Heh heh, I even found "4200 mAh" Ultrafires. Anyone who believes that deserves to get suckered.

BTW, in Your case, You use 3 18650's, so it would be 9,3 Ah. Even if they don't keep capacity to single mAh, it's a gain of 1/3 power draw frome each cell - realistically, I would expect 9Ah of practical power.

Yeah, but it'd be a lot more expensive. This mod cost me a grand total of $10 and the phone already lasts a very long time; I just don't have the motivation to spend three times as much money to increase runtimes another 50%.

Runtime report: yesterday I spent about an hour browsing the Internet on 3G, along with the normal non-Internet phone usage. The battery gauge had gone down by exactly one notch from full by the time I went to bed.

Last edited by Fallingwater; 2012-09-07 at 11:21.

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	Estel	2012-09-07 , 21:21
	Posts: 5,028 \| Thanked: 8,613 times \| Joined on Mar 2011	#15

Originally Posted by vi_

Highly doubtful...

Hey, we are not discharging N900 on 1A or 2A from single cell... In fact, in dual cell setup, even our average-high 300 mA would be halved, resulting in 150 mA during heavy load, and 250 mA under super-heavy load (and 500 mA being absolute maximum, if You have turned everything that is turnable, + powering something out using hostmode, + torchling on, + CPU @ 100%, +...). For tripple cell, it would be even lower per cell. For this, standard manufacturer's way of measuring via 1/10C discharge (300 mA for 3Ah battery) is absolutely OK for us.

Originally Posted by Fallingwater

What is your country?

Panasonic probably wouldn't lie, but you have no guarantee that the cells have been made by them. The ones you can find locally are probably Chinese fakes with "Panasonic" printed on them, especially if they're cheap. Genuine 3.1Ah 18650 are quite expensive; I've had a look, and I can't find them for less than 12 euro each shipped from European sellers.

Yea, I was talking about price tag 9-12 euro, locally. It's still cheap, compared to cost of dual-scud, or dual-polarcell, or any other 2 flat batteries, used to create 3000 mAh dual-mod one.
---

As for 3,8Ah, I also haven't confirmed it, but from initial info, it was also Panasonic (successor of the 3100 model). Maybe it was hoax, after all.

Still, 6Ah battery from two 18650's, bundled *inside* device (with total thickness little more than N900 with mugen cover) is neat for me