Dell Precision M4600 Laptop Slice Battery Support?

[Davide-NYC]

I have three Dell M4600 Precision laptops. They are very good for the price I paid and have given me years of service.

I wanted to add an extra battery to my laptops and purchase the KJ321 slice battery for this purpose. Assuming that the E-Dock port underneath the laptop would support this battery.  I purchased two of these slice batteries and charged them up overnight.

Turns out they are not supported, except that they are… ... allow me to explain.

The Slice battery is identified correctly by the ePSA Pre-boot System Assessment, but not the BIOS and thus, not the OS. In my case the OS is Windows 10 Pro (64 bit)

Here is the primary battery installed, properly identified:
Primary https://ibb.co/xz6nLhj

Here is secondary battery installed and properly identified:
Secondary https://ibb.co/RzHMWPj

Here are both batteries, installed and properly identified:
Both https://ibb.co/zs5r4f3

And finally, for good measure, here are neither batteries installed and properly identified:
Neither https://ibb.co/QXBm7JZ

Is there a way to provide support for this battery in the BIOS? Is there maybe an alternative BIOS that allows for this. Seems like it should be possible.

Thanks, Davide.