Hello dear Ti comunnity :)
I'm looking for solution to switching between two batteries which are used to power up whole device (Boost converter followed by LDO's).
What I want to achieve is little uncommon solution so :
BAT1 will be primary power source and BAT2 will be secondary which will be active when BAT1 will be depleted/removed/damaged.
I know that I can use PowerMUX or ideal diodes with enable input to control voltage of BAT1 via comparator or battery monitoring IC to make ideal cut off / source switch.
But I'm looking for something more useful which will give me more freedom in terms of charging.
So I want to achieve charging of BAT1 when BAT2 will be used and vice versa to mantain proper discharging of both batteries - this is my main goal here.
I want to avoid as much as possible any mainentrance due to battery replacement or switching them in place (reconnecting them at PCB) due to nature of Li-Ion bat.
I'm not looking for charging both batteries in the same time or discharging them equal (because I found some solutions that working this way).
My charging current is ~ 2A which is rather typical (wall adapter 5V/2A), I'm using dedicated IC for charging Li-Ion battery (both are 18650 type 3.7V).
Cut off voltage will be 2.7-3V then second power supply will be turned on to maintain proper operation and 1st bat should be charged until it will be charged at 95%
When BAT1 will be fully recharged it should be switched back to power up device, then BAT2 is going to recharge.
Wall adapter will be connected all the time but only to maintain charging (not as a 3rd power supply option).
Is there any IC solution for that ? I assume I will need some MOSFET's but how to control that charging sequence?
What if both batteries are depleted (wall adapter disconnected/damaged etc.) which battery will charge then?
Let's assume both 18650 will be at ~ 2.7V - we are not talking about removed /damaged cell - both will be connected all the time.
Thank you for time and help :)
PS: sorry if my post does not belong to this forum, if there is more suitable place for my question then please move my thread to proper place.