Learn Spanish (Latin America): No hay pilas para la linterna aquí. - There are no batteries for the flashlight here.

We use para because it indicates purpose or destination. The batteries are intended for the flashlight. A good rule of thumb is to use para when you can swap 'for' with 'intended for' in English.

Why use hay instead of están if we are talking about location (aquí)?

Even though we mention a location (aquí), we are talking about the existence of batteries in general, so we use hay (there are). If we were talking about specific batteries we already knew about, we would use estar, as in Las pilas no están aquí (The batteries aren't here).

Why isn't there a word like unas or las before pilas?

After the verb form hay, we never use definite articles (el, la, los, las) because hay introduces unspecific things. Since we are saying there are zero batteries in general, we don't need unas (some) either. We just leave it blank: No hay pilas.

What is the difference between pilas and baterías?