携帯電話の電池がすぐになくなるって英語でなんて言うの？

How annoying is it when your mobile phone battery runs out quickly? You wait a long time for it to charge, only for the battery to be dead a few hours later!

When we talk about the battery on our phone, we can say "phone battery", "battery", or even just "charge".

We are all familiar with the effects of poor battery life and the batter may be well-described by the adjective 'duff'.
"I need a replacement battery as this one's duff!"

You can say that your phone can "drain" or " dies" as they both mean that the battery loses its charge quickly.

1. When the phone battery life runs out quickly, you can explain that it "drains" quickly. If something is draining, this usually means it's not holding the electrical charge very well, and therefore it goes down or drains away.
   
   2. If your phone dies really fast, this usually means that the battery runs out of charge quickly. Therefore, if you explain simply that your phone dies, it is widely understood that it has a battery problem without specifically saying the battery dies/drains.

People say phone battery or phone charge. Both can be used interchangeably. It usually happens when your phone is getting old and needs to be replaced or taken to the store for maintenance. Adding "horrible" to the sentence shows your frustration with your phone and it is a pain everyone will understand.
Hope this helps!