Extended batteries are getting crappier, at least the ones from Spider-Foot (and by extension, most of the other nameless OEMs):
I was impressed with the performance of my spiderfoot battery, so I bought three more and tested them. It looks like the newer batch isn't as good. Maybe they changed suppliers once their name has been established?
If anyone's interested, I've uploaded the graphs here:
https://s3.amazonaws.com/eug/SpiderFoot-3.5...attery-Test.pdf Summary:
- The stock battery rating is accurate, 1,617mAh at 500mA with a 2.8V cutoff.
- The first SpiderFoot 3,500mAh battery measured out at 2,413mAh on the third cycle. At the 7th cycle it was 2,396mAh.
- The second SpiderFoot 3,500mAh battery had an average of 2,146mAh on the 3rd, 4th, and 5th cycles.
- The third and fourth batteries had similar characteristics the first charge cycle had a lower capacity (2,018mAh and 2,041mAh). The second, third, and fourth charge cycles were pretty even with an average of 2,126mAh and 2,135mAh.
At 2130mAh, I would rather get the genuine 2,000mAh battery - it's a lot slimmer and lighter.
I'll use it a bit more and see how it goes in a month or so.
Taken from eug at XDA, one of the guys with the cap testing rig.