I have an STM32 based vehicle tracking circuit with an SIM808. I want to use it in vehicle with an LM2596 regulator and a 3.7V li-ion backup battery.
I searched and found out that there are two topologies as attached picture. I need to know which topology is better according to li-ion li-polymer cell internals and increase its lifetime.
Question 2: What is the recommended way to implement that topology?
Our load must continue its working during power switch without interruption.