Mobile is not starting up - Xperia U

Hi Team,

My mobile is in switched OFF state for last 5 months. I have changed it for whole nigh'== Heading text ==t and tried to start but not worked. I have googled and tried to switch ON by pressing volume button and power button for few minutes but no luck. Please let us know how to fix it.

Remove the battery and charge in another phone or adapter and check the battery voltage or replace battery it will work 100%