RE: Inspiron 7537 - Battery Not Charging
DO NOT update the BIOS without a functioning battery. Not only is that risking the mainboard, but it will not solve the problem.
Unplug the system, remove the base cover and disconnect the battery. Hold the power button for 30 seconds and reconnect the battery. If it's still not recognized thereafter, the battery needs to be replaced.
If you're under warranty, call Dell for a warranty replacement of the battery.
If the system is out of warranty, you can get a repair estimate
there is a charge for the estimate but it is applied to the cost of the repair.