Almost certainly bricked device, looking for advice
Yep 100% sure it's hard bricked as the qloader 9008 shows up. 

The whole eMMC is damaged or just the boot partition. But as it was caused by a faulty battery, I guess it is damaged completely and would need to get replaced (eMmC chip).

There is 3 methods that can be used to recover the device: 


Repairing via an SD Card (for corrupted boot partition)
Repairing via JTAG (need JTAG interface, soldering in the main board, etc,)
Hardware replacement if the above didn't solve the problem.


After successfully completed the above, yoi should be able to flash a firmware normally.