Power system for DIY laptop

[UnbrokenMotion]

First off, i'm new to the forum, hello everyone!

Anyway, I am currently building a laptop that uses an Realan LR1106-250W12VDC power supply. Thanks to the 11.8v ~ 12.5 volt variable input on the power supply I can power the entire computer off of a battery pack.

However, I am unsure as to how to balance charge five 6P battery packs in series. I know I can use an 18650 protection PCB but I have no idea how to wire the battery pack itself. Do I need  resistors between cells? Diodes? How does this work?

Would it be easier or even feasable to put all of the batteries in parallel and use a boost converter?

Also, is it possible to integrate the battery so that windows detects the battery as part of the system?

[edavid]

How  can you use a 5S pack when the maximum PS input is 12.8V?

[grifftech]

How  can you use a 5S pack when the maximum PS input is 12.8V?

buck converter

[zv_odd]

Having pulled apart a few battery packs... They are usually wired in series, 4 - 8 cells at a time with sense wires (center taps) between each cell. The ones I've seen (Lenovo) had Texas instruments ICs designed specifically for the task.
The keynotes from this cyber security talk on battery firmware as an attack vector, has an good teardown and part explanation of a macbook battery.
https://media.blackhat.com/bh-us-11/Miller/BH_US_11_Miller_Battery_Firmware_Public_WP.pdf It also gets into the firmware component of the battery.

An overview of the standard low level computer power management BIOS API (ACPI) can be found here: https://en.wikipedia.org/wiki/Advanced_Configuration_and_Power_Interface.
So I'd guess it's usually the BIOS implementing this API and talking the System Management Bus https://en.wikipedia.org/wiki/System_Management_Bus using Smart Battery System https://en.wikipedia.org/wiki/Smart_Battery_System
Bonus http://www.pmbus.org/Specifications/CurrentSpecifications