I do not recommend that a novice user ever try to update the BIOS. If you make a mistake the computer might not work at all. Then you will need to return it to the factory to have a new BIOS chip installed.
Have you called Dell and/or run the hardware diagnostics that are built-in to your laptop? Pull F11 multiple times at start-up and you should get the Dell diagnostics scree,
Was this laptop purchased from any of our retail partners? If yes, how old is the computer?
Try the below mentioned steps and see if these steps help:
1. Disconnect all peripherals and confirm if system is working fine with AC Adapter only.
2. Remove AC adapter, Battery and drain flea power by pressing and holding the power button for 10-15 seconds. Re-connect the AC Adapter and battery and check if the percentage of charge increases.
3. Check the AC Adapter status in the BIOS. Ensure it is not Unknown/Not Detected.
4. Try charging the battery with the notebook powered off.
5. If any of these steps do not work, please follow the steps suggested by `xpcman'.
Note: Plug your computer to a good, working UPS before you update the BIOS. If you experience a loss of AC power or a significant voltage sag/spike during the BIOS flash, you will either have to buy a new BIOS chip or buy a new motherboard.
6. Try swapping with a known good battery (if available). If known good battery works, the battery is faulty.
7. As suggested by `xpcman', try running "Primary Battery test" using Dell Diagnostics. Click here to find steps on how to run Dell 32-Diagnostics.
7. Run the "MS-Fix it" for "Fix power consumption problems and extend the laptop battery life". Click here to access this "MS-Fix it".
Do reply with results.
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