Help with Battery fuel gauge and cell balancing chips. Total Confusion

Good evening everyone,  i am  a junior electronics engineer and i am designing a new 4s 20Ah Li-po Battery management system for a portable instrument and i am somewhat confused regarding to the chips i  found so as to build it.

All i want to do is to supply the instrument through the 4s Li-po and, if the battery needs charging i will charge it through a wall adapter and also supply the instrument at the same time so as to function.   

For this purpose i was thinking of using a standalone charger chip with power-path . The bq24617. So far so good i think.

Next, i need a  balancing chip for the battery's cells. And here is where the confusion begins.

 After lots of searching and comparing chips it seems to me that there is no Standalone cell-balancing chip (to keep things as simple as possible) but instead i found these fuel gauge chips: bq40z60, bq40z50-R1, bq78350-R1  and
 these  monitor chips: bq76920, bq76200 that fit my requirements.

Now, the problem is that i don't know which of these chips would be the correct one to use (or in what combination) for my design  since all of them have, more or less as i see it, the same abilities and functions. For example all of them have Battery voltage monitoring ,Current monitoring, Temperature monitoring and most important cell balancing.

For example apart from the charger Should i use only bq76920 or (bq76920 together with bq78350) or bq40z50-R1?

I hope you can help,

Thank you for your time.