Samsung Semiconductor held its Foundry Forum this week and announced a breakthrough in its fabrication process for making the Exynos chips that power its Galaxy smartphones. The new technique will give the company at least a 12-month lead on the competition in moving to the 3nm process that will result in a 50 percent boost in battery life just in time for the Galaxy S12.
https://www.notebookcheck.net/Minimum-50-battery-life-boost-for-Galaxy-S12-over-S10-thanks-to-Samsung-fab-breakthrough.420884.0.html
Nah, no chance. Knowing how manufacturers operate, they'll just reduce battery size and claim it's enough because of the power-efficient chip...except, cellular modem and screen are one of the major battery killers and nanometers won't affect their consumption. So chips may be 50% more power efficient, but i'd guess real-life authonomy gain will be 10% to 20% at best and they'll probably put 10%-20% smaller batteries anyway...
IIRC advertised efficiency and performance gains are mutually exclusive, and yes as the other guy said screen consumption is a major issue, but the modem is integrated in most of Samsung's SoCs, and should a 5G modem be discrete it would also need to be manufactured on the most advanced process, or maybe one generation behind.
Another issue is that either Samsung's 5nm or 3nm node density is actually projected to fall significantly behind TSMC, but I can't remember which.