arduBMS

Hi,
I want to build a bms for lithium battery. The key is to measure the voltage of each cell connected in series...

Using voltage dividers for every cell is ok for only few first cells thus the precision of measuring drops for every cell that we add...

My idea is to use some multiplexers and connect one cell at the time to charge a capacitor, and then disconnect the cell and connect the charged capacitor to arduino and measure the voltage... This way arduino could be powered by the same battery pack that he is measuring...
The only multiplexer I found capable of high voltage(72V) is the max14752... Is there any other possibly not smd?

When I have the cell voltages, It is easy to do everything else regarding balancing, voltage protecting, and It can be used for any type of lithium battery by just changing the parameters in the code.... Then I have the possibility to write all the data to some lcd, making graphs.......

Is this Idea any good?

Major problem will be accuracy, the atmega ADC is only 10 bit resolution. I'm working on an arduino BMS based on TI's BQ76PL536A chips, which are all in one , stackable to 192S, 3-6S lithium monitor/balance chips.