2 battery (?) problems

[RemixJ]

Hi, sorry for likely mistakes cause i have to write fast
My phone is sony xperia z1 compact
My first battery ( more likely software) problem is that my battery drains from 50-30 to 0 in seconds many times(not always though)

Second is that my battery shows x% and after reboot y% is completely different (70 to 5 and after 4 reboots 55)

Ive tried repairing phone trough pc companion but nothing helps
I have a locked bootloader therefore no rw system directory and i am rooted
Thanks for help

 

[RemixJ]

@RemixJ
xperia devices battery life is usually about 1~2 year.
I think you have battery was deterioration.

So a battery change would help?

 

[alex_hk90]

So a battery change would help?

It could do; quite a few of us had a similar problem and changing the battery solved it:
http://xdaforums.com/sony-xperia-z1-compact/help/battery-reporting-phone-dying-suddenly-t3095120

 

[RemixJ]

It could do; quite a few of us had a similar problem and changing the battery solved it:
http://xdaforums.com/sony-xperia-z1-compact/help/battery-reporting-phone-dying-suddenly-t3095120

k then, nothing else to do since i love this phone and i wont change it, Thank you all for help