XPS 15z (L511Z) Laptop battery not charging

Hello all! I have an XPS 15z AKA the L511Z.

The laptop will not charge the battery anymore.  Here is a list of relevant facts:

• When it is plugged in the battery level does not go down at all
• When the battery is removed, the AC adapter will run the laptop.
• In the BIOS the "AC Adapter Type" says "None". 
• In windows the current battery says  "2829 hr 44 min (65%) remaining"
• The current BIOS is A10 and I would like to update to A12 but it requires that both battery and AC adapter be connected.
• I have ubuntu on dual boot (if this helps).
• This problem first occurred after a windows update, but using restore point did not help.
• The laptop is refurbished and out of the 1 year warranty.  After having some trouble with audio during the warranty period, the motherboard was replaced and 3 months later this problem has arisen.

Any ideas on how to fix the problem?  I would really like to flash to the newest A12 bios but have been unsuccessful so far after trying the following:

• Starting Command Prompt as administrator and running the bios install with the /forceit command > still requires that charger+battery be recognized as attached.
• Running bios install from boot USB stick > "program cannot be run from DOS"
• Remove "Microsoft ACPI-Compliant Control Method Battery" driver within device manager > no effect