Battery, CMOS, and POST issues with HP Envy 15 x360

[silflay3]

I recently had issues with the battery no longer holding a charge / being detected by the laptop about a week ago.  This resulted in a "CMOS checksum" message when I boot up my computer as well as a Battery warning and a suggestion to have it replaced.  This usually causes the laptop to take a VERY long time to boot up (probably literaly 5 minutes).  The laptop also can't seem to keep the time anymore.

Reading from this thread:

http://h30434.www3.hp.com/t5/Notebook-Hardware-and-Upgrade-Questions/Envy-x360-battery-short-and-CMO...

It seems that there isn't a dedicated CMOS battery.

The laptop could be powered on through the AC adapter.  The moment the AC adapter plug is disconnected, the laptop shuts off, leading me to believe the battery can't function anymore.

I replaced the battery with a matching one from amazon.  The battery seems to work since I can remove the ac plug without having the laptop suddenly shut down, but I still get the very long boot up time, and now it seems that the laptop can't detect the battery.  The indicator in the taskbar indicates "Plugged in / not charging" or "no battery detected".  I no longer get any messages related to the CMOS or the battery, but booting up the computer still takes a very long time.

I've tried accessing the BIOS and tried to make all the settings adjusted to the default, but this doesn't seem to help.

The warrenty has expired for the laptop and I would to see if there's an easy way to resolve the issue as it is right now.

[C001u5_Cl4y]

HI.silflay3

Try updating the bios:

HP PC Hardware Diagnostics UEFI

5.9.0.0 Rev.A

24.3 MB

Mar 20, 2016

http://ftp.hp.com/pub/softpaq/sp72501-73000/sp72853.exe

HP Notebook PCs - Updating the BIOS | HP® Customer

Let's see if we are lucky with the problem.

Regards.

[silflay3]

No luck with that solution.

Oddly enough, I don't think that UEFI contains a BIOS file.  I get the following error:

"The selected BIOS image was not available.  You may select an alternate image file, or cancel the update."

Going through the directories, I can't find any BIOS images that are different from the current one when I install the UEFI into the hard drive partition.  Installing the UEFI into a USB drive leads to empty folders in the BIOS directories: "Current" "New" and "previoius" comes up empty.

I've tried reflashing the same BIOS that was in there, but that didn't seem to help either.

The current BIOS version I have installed is F.26, 1/19/2015.

Using the same UEFI, I attempted to run a battery check, but the interface "freezes" at 1%.  The interface seems to be able to check the processor fine.  I don't know if this might narrow down my issue.  This is with the third party battery.   I'll attempt this again with the HP battery that it initially came with sometime tomorrow.

[silflay3]

Attempting to run a battery check on either of the batteries (the original battery and the replacement) runs an error that says "No battery is installed" Could something else be wrong here?