Question Laptop needed AC power for first time after battery replacement

[mmp09]

I have a strange observation. I recently changed the battery of my HP 245 laptop. I installed what is called a Compatible One (Not made by HP but by other vendors meeting the exact specs) After I secured the battery in place, I closed the back panel and pressed the Power On button.

However nothing happened as if battery is dead. No POST, no backlit on screen. Nothing.

I reconnected the battery just in case and same observation.
So I thought battery is DOA. So I decided to check what happens when I plug in AC charger.

This time Laptop powered on when on AC charger. Upon booting into Windows, it showed good battery health and charge at 90%. So there was no reason for laptop not to power on the first time. Now after I turned off Ac power, laptop did not abruptly shut down (as expected) and now even if AC is not plugged in Laptop properly powers on only on battery (as expected).

Now laptop is working fine.
So why it did not power on for first time when on new battery? Has anyone noticed such a behavior?

I have never seen such a behavior so far.

 

[helpstar]

This laptop doesn´t have a cmos battery, if main battery is dead or replaced, the cmos resets and has to "reinitialize" (mostly automatically) before the battery is recognized correctly. date and time as well.

 

[mmp09]

@helpstar - Thanks for your input. So does it mean that this behavior was Normal?
Date was reset to some day in 2017 if I remember but not 1900.

 

[helpstar]

yes, that´s normal.
usually the date is reset to the date of production or whatever the programmer likes to be the first date