Xperia ION root removed, battery run down to 0 percent and now Doesn't turn on help!!

hi guys i am roockie with the xperia ion I buy this phone to my brother but since i remove the superSU root first and then i wait until the battery run out to 0 percent to charge fully the battery again the phone Doesn't turn on anymore, i follow the steps to charge the phone 53 hrs to see the led lights and nothing happen, do you thing that the battery Doesn't charge? the phone is dead.

please help and thank you

battery goes for 15 percent straight to 10, then to 5, then dead.

so lately my battery is being annoying. I'll hit 15 percent, then outta nowhere it goes right to 10, then all of a sudden I hear the beeps again and my brightness lowers and i'm at 5. wtf?

then within like 30 seconds, it's dead and the phone is shutting off.

now, it did this before a factory reset, and again after one. I'm still in kitkat 4.4.4.

the battery status is fine, and it's not bloated or anything. I hardly ever use fast charging so I have trouble believing that within less than 1 year of the phone, the battery died already.

my battery life in general is garbage and i average maybe barely 3 hours screen on time a day at like 16 hours off charger... but what this is doing I've never had happen on a phone before.

any thoughts?

Sent from my Galaxy Note 4