Notebook Hardware and Upgrade Questions

Hi there, 
Good day.

I have a critical issue and I hope to find the answer here.

My laptop `HP ENVY Laptop 13-aq0xxx` which I bought Dec. 2019 is facing a "sudden" issue in the battery.

What is it? Say I have turned off my laptop while my battery was 60%, then the next day I turned it on, it then boots normally and when I got the lock screen. the device is suddenly shut down, and it's not a normal shutdown, it is like a power outage while there is no battery plugged in "which is not true of course", and then it doesn't respond to turn on unless I plug in the charger, and when I turn on, I find the battery still 59%, not 0% or so.

Can not determine what is happening.

One more thing, when I got this, then I immediately test the battery health using hp support assistant just after the device is turned in after this situation, I find the health is weak. and when the battery is completed charging, then the health is normal again. so the status is not stable, neither the mentioned sudden shutdown. 


One last situation, now the battery was 40% and suddenly the device is powered off the didn't respond to power on unless I plugged the charger, and I found the battery became 1%

I don't know what is the root cause, but last week I have been working on the battery for like 4 hours and the current capacity was almost 40000 out of the design capacity which was 52000, so I don't think there is normal behavior to be that bad in one week.

I hope to get an answer to this.

Thanks