Hai,everyone

i have some questions about the word "dead" here.
The first question,
does the word "dead" mean that not able to be used anymore/finished when using in
informal/spoken English?
For examples:1) A dead match.
(that means it's unable to be used anymore,right?) 2) A dead battery.
(that means as same as above,right ? )But as far as i know that "dead" can mean
not working because of lack of power.
For examples:
1) My cellphone is dead. (
that means i has run up the power of my phone,right? )
Therefore,i'm wondering that if i say this cellphone is dead,
does it mean
it's unable to be used anymore/broken or it's has run out of power ?Thanks in advance
