Best battery life combo?

[GeekyTanuj]

Wanna ask for the suggestion of best rom + kernel + kernel settings for the most extreme battery performance on our ghost?
(Android version doesn't matter!)
Even tips for a better battery life on stock Lollipop/KitKat would be highly appreciated!

 

[Jekodark]

I'm using LineageOS 13 + 3.4.113_mm_x_kernel_v1.5 and battery life has increased A LOT. I was very surprised. Also performance are better!

 

[Y_Yan_C]

I'm using LineageOS 13 + 3.4.113_mm_x_kernel_v1.5 and battery life has increased A LOT. I was very surprised. Also performance are better!

how many hours screen-on?