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-   -   1930 mah battery... (https://talk.maemo.org/showthread.php?t=32330)

daveb70 2009-10-01 19:47

Re: 1930 mah battery...
 
Quote:

Originally Posted by Lord Raiden (Post 337728)
As for the question of battery capacity, your total number of cells determines your top end charge capabilities. For smart batteries with smart circuits, and a unified cell design, you simply control the maximum charge by changing the cell firmware. So by rights, a 1200mah battery and a 2500mah battery of the same size and form factor are identical (assuming the unified cell design), save for the cell firmware.

Hmmm, I was under the impression it was more a factor of quality, similar to how CPU processors which may all churn out from the same fabrication plant are binned according to speed, and obviously their cache has to function. (or they may turn into crippled Celerys of yesteryear)

In my long ago days of R/C car racing we'd always pay more for higher capacity cells. Cheaper cells (fewer mAh) were also less likely to be matched (putting simiilar charge/discharge curved cells together in a pack). I can't imagine even with lithium-ion batteries companies would make high capacity cells and put them in a pack, cripple them with limiters (in a very loose sense) and then sell them as lower cap batteries. Maybe I'm misunderstanding Lord Raiden's take on what I quoted above, or "smart battery" production technology does not agree with me and appears wasteful and costly.

I would hope that even the cell/portable device battery industry would work in the same manner, giving legitimate reason for charging more for a battery with higher capacity- because they are either harder to come by (elite picks from the QC department) or they cost more to make.

I won't speak for misrepresentation of capacity by foreign knockoff battery brands. We all know we take risks buying cheap. YGWYPF

qole 2009-10-01 19:49

Re: 1930 mah battery...
 
Quote:

Originally Posted by zkyevolved (Post 337573)
... all you'd need is a DIYS Nokia Battery Door Kit! Home Depot anyone? Lol. Someone get out the easy bake oven and some clay! We're making an extended battery cover :D

That is going to be VERY tricky to do, since the sliding camera door is partly over the battery at the moment. If you want a bigger battery in the same slot, it is going to require some differently shaped batteries, at the least (they can't be a constant thickness for the whole length of the battery).

But a new third-party back cover with a big kickstand would be nice.

mece 2009-10-01 20:03

Re: 1930 mah battery...
 
I'm always sceptical when it comes to cheap batteries. I've managed to bloat a couple of cheap lipos (while charging, with a proper charger. Talking rc batteries here) without doing anything wrong. If you're not there when it happens, so you can turn it off, things go bad. Very bad.

Here's a youtube video of some finnish rc guys demonstrating the bad mentioned above:
http://www.youtube.com/watch?v=YCWdnjLqVWw

R-R 2009-10-01 20:11

Re: 1930 mah battery...
 
Anyone has the gear to test this battery and compare it to a stock BL-5J ?
Also on the safety/construction side afterward ? :)

zkyevolved 2009-10-01 23:25

Re: 1930 mah battery...
 
Quote:

Originally Posted by R-R (Post 337771)
Anyone has the gear to test this battery and compare it to a stock BL-5J ?
Also on the safety/construction side afterward ? :)

I would chip in a few bucks to the purchase of this for testing :P I'm just curious! LOL.

But I will be purchasing a second battery and an external charger (so I don't need the battery in the phone to charge it, that way every morning I'll have two ^^) hehe.

Lord Raiden 2009-10-01 23:43

Re: 1930 mah battery...
 
Quote:

Originally Posted by daveb70 (Post 337751)
Hmmm, I was under the impression it was more a factor of quality, similar to how CPU processors which may all churn out from the same fabrication plant are binned according to speed, and obviously their cache has to function. (or they may turn into crippled Celerys of yesteryear)

In my long ago days of R/C car racing we'd always pay more for higher capacity cells. Cheaper cells (fewer mAh) were also less likely to be matched (putting simiilar charge/discharge curved cells together in a pack). I can't imagine even with lithium-ion batteries companies would make high capacity cells and put them in a pack, cripple them with limiters (in a very loose sense) and then sell them as lower cap batteries. Maybe I'm misunderstanding Lord Raiden's take on what I quoted above, or "smart battery" production technology does not agree with me and appears wasteful and costly.

I would hope that even the cell/portable device battery industry would work in the same manner, giving legitimate reason for charging more for a battery with higher capacity- because they are either harder to come by (elite picks from the QC department) or they cost more to make.

I won't speak for misrepresentation of capacity by foreign knockoff battery brands. We all know we take risks buying cheap. YGWYPF

Well, you are right in the fact that OEM's will sell inferior batteries in the lower MAH categories, just like the chip makers sell chips that can't be clocked to full speed as their less speedy siblings. But if they can't get enough of the lesser or "semi-failed" units to fill the orders for the smaller capacity batteries, they'll simply "downclock" (to use a cpu term) the higher capacity batteries to fill those slots.

As I said, to save money they use one common battery, and then label and program them based on how they perform. So if you had the bios code for the smart chip, you *could* take your battery up to the higher capacity, but then it may or may not give you full capacity and may risk some nasty side effects. And again, this is using the unified cell design, similar to the BP-4L and others like it. This doesn't apply to the ones that use separate cells, where more cells = more MAH, such as laptop batteries.

Another side note. Laptop batteries and multi-cell designs tend to be "dumb" batteries, in the fact that the smart charging chip is actually on the unit itself, and not the battery. Smaller devices like the NITs, phones and such have to offload that work to a tiny chip on the battery itself.

urnass 2009-10-02 00:53

Re: 1930 mah battery...
 
I'd be dubious about the battery too, but here is a device that measure battery discharge capacity (mAh). http://www.californiasailplanes.com/supertest.html. It says it works with NiCD and NiMD batteries, but it should work for any battery. I'm not sure of the normal load on the battery (mA), but I'd pick the 125mA setting, as to high of a setting could damage the battery.

Here a pricer option:http://http://www.siriuselectronics....roducts_id=348

The basic test method required integrating the battery's current over time. This is most easily done by connecting the battery in series with a current meter / multi-meter and a resistor (appropriately sized to give a reasonable current draw on the battery). Then measure the current over time (shouldn't change much till the battery nears the end of it's life). Plot the data; calculate the area under the curve and you have the battery's capacity in Amp-hours or mAmp-hours (depending on the units used). Assuming the maximum current draw on the battery is 100ma @ 3.7V, you'd need a 37ohm resistor (or something close). If the battery really is 1950mAh & you only drawings 100ma, this test would take 19.5 hours.

Lord Raiden 2009-10-02 01:02

Re: 1930 mah battery...
 
That product is only or RC toy batteries, and it's a bit dated considering it deals with the <1000mah battery group. What you need is a battery tester that specifically tests Lithium Polymer batteries.

Rushmore 2009-10-02 01:07

Re: 1930 mah battery...
 
Quote:

Originally Posted by AnimalMind (Post 337435)
I have wondered if you could do something like this without hurting the phone. I upgraded my G1 battery from the standard 1200mAh to a 2300mAh and did not notice anything negative.

Is there a reason NOT to do this?

-- AM

I just ordered the N900 today and also have a G1 with 2,300mah battery. G1 lasts two days with it (but no 3G radio on).

I will be interested in this battery for sure.

Jason404 2009-10-02 01:13

Re: 1930 mah battery...
 
Apply Occam's Razor. Surely if such high capacity batteries were available, that did not have any downsides, Nokia would be using them as OEM?


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