New Delhi, Dec. 29 -- Cold weather has a way of exposing things we normally ignore. Pipes act up. Skin dries out. And phones, suddenly, start behaving strangely. The battery that felt dependable a week ago now drops from 40% to single digits without warning. You step outside, check a map, and the phone shuts down. Back indoors, it springs to life again as if nothing happened. It feels like a fault. It isn't.

Most smartphones use lithium-ion batteries, and they don't enjoy the cold. Lower temperatures slow down the chemical reactions inside the battery, which reduces how much power can be delivered at a given moment. The phone hasn't lost charge overnight. It just can't access it properly while it's cold. That's why the problem feels dram...