Quote:
Originally Posted by setset
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.
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I might not have made it clear.. We
aren't talking about an actual linear discharge here... You take the semi linear curve based around the nominal voltage.. and take the
derivative of the curve... THAT will give you a linear discharge... We aren't talking about the actual discharge, we are talking about integrating the curve.. You then create a calibration and model based upon the derivative of the nominal voltage and reconstruction reporting values based upon this data... Assuming nominal voltage is hit at <90~100 (in that range) and >~10 ... Then you create a minimum voltage before total discharge (usually around 1/2 nominal) and set that as 0 point.. Then creating reporting levels at 5 (halfway) and 3 (point at which basic functions should be dumped except basic phone calls).. 0 point is set at the recovery voltage (anything below that and you can have cell damage which will lead to a decreased overall capacity)... I agree with you on the cell design and capacity but the problem is with standard Lithium polymers that are currently avalible you can't reach sufficient density to increase capacity without increasing size (and cost).. When
olivine-type lithium iron phosphate becomes cheaper, we will see a capacity increase due to higher achievable densities.. There is also a newer lithium cell structure that i think samsung or someone else is developing that will increase density ~50% over standard (1.5 times standard densities) but the cost of these is to high for mass production in portable electronic terms..
Also look into the research done at Bringhamton University where they can increase olivine lithium ion cells by introducing vanadium into the cathode material..