Lenovo P2 is good choice if battery life is your primary concern.
Premium looking phone with amazing battery life, turbo charging feature and good disply quality, speedy proccecor run apps and games without lags and hang, above average cameras, accurate fingerprint sensor and great call quality makes it a good choice.
Cons. Slightly heavy to hold becouse of the battery size
Overall sure shot choice for a smartphone if battery primary concern. One of the best smartphone from lenovo.