Quote:
Originally Posted by numus
Setset... very accurate in some aspects in a techincal brief, but none of that has to do with the problem with the moment and it's battery life 
The problem is pretty simple in the end..
All these devices can't utilize a direct volt or amp meter.. They utilize an ADC circuit and then use a calculation to determine voltage... they then integrate the voltage curve over the nominal voltage and create a linear decay curve that represents the majority of the voltage except for the very top and very low (very top you have a massive voltage dropout between max voltage and nominal voltage and the same at the bottom... massive dropout after nominal voltage into minimal voltage).... Now this is all fine and dandy and works VERY well in the end.. Except that for the moment they are utilizing an INCREDIBLY low resolution ADC which doesn't include a buffer region... The behold II on the other hand uses a 9bits calculation and has an incredibly HIGH buffer range per voltage (moment outputs ADC values as 10^3 while Behold II outputs adc values as 10^4)... This causes a problem when you have a large demand on the power system, since the voltage is a order of magnitude less then what it should be, any small drop is percieved as a huge voltage change...
I have written all this up over at SDX and explained how i modify the ADC values from stock to integrate a better buffer region so it doesn't drop off to 15% so fast BUT my new decay curve is to linear for my liking (it is based off the numbers samsung calculated and they aren't right (i haven't had time to actually recalibrate the curve) so with the modified cl14 kernels, it isn't as accurate as it was with teh cj05 kernels (since i modified both of them and the cj05 code's decay curve looked incredibly better.. but the values were off in my calculations)...
I have wrote all this to samsung and asked them to switch over to 9bits for higher resolution and got 1 response from the actually code programmer that they would look into the possibility of utilizing this... but no promises |
Thank you for the reply. I have no info on the actual coding and just wanted to contribute what I know. I've bolded your quote and wanted to touch back on that.
In order for a linear decay curve to work effectively, only 1 chemistry of Lith-ion will work. That's Lithium Manganese aka Sony Konion. The Konion cells are very nice in the sense that that act very much like SLA's but have a much higher energy density. They are also very robust in the sense that they can handle low voltage drain very well.
@ColdStart. To answer you bluntly, yes. We have crappy batteries. Don't feel too bad as this is not just us. All cell phones currently use these batteries. Prismatics cell designs are effective for slimming down the battery but they have a lower energy density than traditional cylindrical cells.
I'm seeing a shift in market trends. Laptops and cell phones are pushing for better battery technology and I just wanted to show you they already exist. The problem right now is mass manufacturing costs. Instead of thinking that there is a wall, just think of it as they haven't caught up.
Many threads are started about improving battery life and I completely agree on that. Those of you guys who are working on it are great! I still believe we need more capacity. Cell phone are getting faster, their screen are getting bigger and yet
the "limit" of batteries is still around 1500 mAh? That can't be right. 2 AH should be the minimum standard today, as I write this.
Think about tuning a car. Why spend time and energy tuning a corolla where you could tune a supra? We need a good base to start with and if we want the most out of our phones, we need to start with a good battery. 1440 mAh may be good a few years ago, but not today. I'm still surprised there isn't an upgraded battery available by Seido yet. Most smart phones today have around the same capacity. My last phone was a MyTouch 3g. It lasted about 1 full working day, the same as my Moment. I've talked to people with other smart phones and they too say they get about 1 full day of use. I guess a good idea is to look at other smart phones and see compare the life they are getting in terms of their batteries.
My guess would be they last about the same excluding blackberries with their smaller screens.