HP Battery after replacement not Calibrating and The CMOS checksum is invalid CMOS error 502

[RuRu_05]

Last month my battery just suddenly stop charging properly, when i plugged-in the power adapter, it charged only 30 sec to 1min then it will stop (btw my Hp Laptop is 3 yr old). I can still use the laptop, as long as the adapter is plugged-in, the battery percentage will not decrease nor increase. When i looked at the battery icon,  Battery % Power Mode (plugged in).  So i ran an HP Battery check, and appeared "Primary Battery: Replace" . So I purchased a new battery,  after putting a new battery, i ran an HP battery check again, and appeared "Primary Battery: Calibrate".  So i tried to calibrate following the guideline that i found in HP Customer Support. After doing all the procedure at the end still the same, still mentioned in battery check that calibration required.

And also after replacing the battery, this appeared on the screen "The CMOS checksum is invalid. The CMOS will be reset to the default configuration and will be rebooted. Please check your Bios setup to see if they change. CMOS reset (502). I've tying to look also that CMOS battery on the motherboard but i can't find.

 I've tried to do some other solution that i've read on this community that had the same issue, but still its not working..  I also reformat my laptop and updated the BIOS and driver for the Batteries.

Please need any suggestion/solution for this issue.. Thank you.