PapaSin69
While it may not fix 'battery life' it does fix things that CALCULATE battery life for iOS.
My 4s is showing a nasty habit of going at 100-75% in a reasonable period of time... even extended (like it would last for 2 days). But once under 40%, it starts dropping precipiticely. The last 2 times I've let it get below 45%, I've seen it either:
1) go to sleep at 45%, then wakeup minutes later at 10%, and then go immediately to 1% and power down automatically. I then tried to restart, and it showed battery needing charging. I plugged in the charger, and as soon as it restarted, I did 3 soft resets. When it restarted after the 3rd, it was at 46% power, not 3 minutes after plugging in the charger.
2) yesterday, I left in the morning at 92% (my wife commandeered my charger saying her 2% was more important). at 3pm, it was at 25%. Wife facetimes me. At the end of the 2 min call, it was at 1%, and immediately powered down. I tried viewing the screen, and got the need charging signal. I then tried power-on and got the apple, so I did 3 soft resets. Lo and behold, it came up at 15%, and ran for 1.5 hours just fine, with me surfing on wifi.
I'm stopping at the apple genius bar today to discuss this. My guess is the PMU logic is flawed, and well, my 1.5 year old battery is likely starting to show wear as well.
But, to your point, phone resets do improve the phones energy consumption or prediction of power needs/capacity-calculation.