Stock based roms will provide better battery life than cm based roms.There is no individual rom with best battery life.You have to try them personally.
It also depends upon how many apps are running in background.
A debloated rom will be faster(and battery friendly?).
A kernel is also responsible.There are many kernels.I cannot tell which has best battery life.You have to try them personally.I would suggest to try apolo kernel.
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