I am going to suggest that you are miss using the battery.

8% is almost dead, and that is the "Blue Screen of Death" for a battery if you do that consistently.

Pun intended from "Microsoft Windows OS"​

The battery manufacturers recommend to not draw them down below 40%. Lithium batteries will last "forever" if you keep them in the upper 2/3rds of their capacity.... I have a Qi wireless chargers installed in all of my phones, and Qi pads all over the house. If the phone is not being used, it is laying on a charger.... the battery has a monitoring circuit that tells the charger to cut back at 98% and from there it trickle charges to 100%, and then it only maintains a surface 100% charge. it will NOT over charge.

I have a 6 years old Samsung Galaxy S with the original OEM battery that is still very serviceable.... I just topped it off to 60% this morning.... for 'storage', it is best to maintain the battery at about 40%, do NOT try to keep it at 100%, that is almost as bad as letting it drain down to 0%

read this for more.

* Battery => How To Maximize Battery Life

 

I have not timed the charging at all, But, having noted that caveat, it seems to me that the 'fast charging' is not charging anywhere near as fast as it was a year ago. I imagine, that very much like most things, time itself is the problem. Very much like me...it's just getting old

JM

 

I can relate to the 'old part', today is my 73rd birthday.

 

And a very happy birthday to you AZ, I'm not far behind at 69, but you're only as old as who you feel! Phil

 

but you're only as old as who you feel! Phil

It might only be a coincidence, but I've noticed that as I get older the spring in my step becomes less springy. The truth is one feels one's age

 

Hit the wrong button But i'm going to be 88 in June, so it's excusable

JM