По истечении срока аренды нужно освободить ячейку для хранения.

По истечении means upon expiration, after the end of, or when ... has expired.

So По истечении срока аренды means something like when the rental period ends or after the rental term expires.

This is a fairly formal expression. In everyday speech, people might more simply say после окончания срока аренды.

Both can express a similar idea, but they differ in style.

• по истечении = formal, bureaucratic, often used in notices, contracts, rules
• после = more neutral and common in everyday language

So this sentence sounds like an official instruction or policy notice, which is why по истечении fits well.

For example:

• По истечении срока аренды... = formal notice style
• После окончания срока аренды... = more neutral/plain

Истечении is in the prepositional case.

That is because the preposition по can require different cases depending on meaning. In the fixed formal expression по истечении, it is used with the prepositional case.

The base noun is истечение:

• nominative: истечение
• prepositional: истечении

So:

• по истечении = upon expiration / after the expiration of

This is a set formal phrase, so it is often best learned as a chunk.

Because they form a chain of possession/specification.

• истечение срока = expiration of the term/period
• срок аренды = term of rental / rental period

So:

• срока is genitive because it depends on истечение
• аренды is genitive because it depends on срок

You can think of it as:

[expiration] of [the term] of [the rental]

This kind of noun chain is very common in formal Russian.

Срок аренды means rental period, rental term, or lease term.

• срок = period, term, deadline, duration
• аренда = rent, rental, lease

So срок аренды is the amount of time for which something is rented.

In this sentence, it refers to the period during which the storage locker/cell has been rented.

Нужно here means it is necessary, one must, or it is required to.

This creates an impersonal construction:

• нужно освободить... = it is necessary to vacate...
• more natural English: you must vacate...

Russian often leaves the subject unstated in this kind of sentence. The meaning is general: the person renting the storage unit is expected to do it.

Russian often uses impersonal sentences in instructions, rules, and notices.

So instead of saying:

• Вы должны освободить ячейку... = You must vacate the locker...

it says:

• Нужно освободить ячейку... = It is necessary to vacate the locker...

This sounds less direct and more official. The implied subject is the renter / the person concerned.

Освободить is perfective, while освобождать is imperfective.

Here the sentence is about completing a one-time required action: the storage unit must be emptied/vacated once the rental period ends. That is why the perfective verb освободить is used.

• освободить = to free, vacate, clear out completely
• освобождать = to be freeing, to free repeatedly, or to focus on process

After нужно, either aspect is possible in Russian, but the choice changes the nuance:

• нужно освободить = the result must be achieved
• нужно освобождать = would sound more like an ongoing or repeated process, which does not fit as well here

Because ячейку is the direct object of освободить.

You are vacating what?
→ ячейку

The dictionary form is ячейка. For a feminine noun ending in -а, the singular accusative usually changes to -у:

• nominative: ячейка
• accusative: ячейку

So:

• освободить ячейку = to vacate the locker/cell

Literally, ячейка can mean cell, compartment, or slot, depending on context.

In this sentence, it most likely means a storage locker, storage compartment, or rental storage box/unit.

So although the core meaning is something like cell/compartment, in natural English this would usually be translated according to the real-world context:

• locker
• storage compartment
• storage unit

Для хранения means for storage.

It explains the purpose of the ячейка:

• ячейка для хранения = a storage locker / a compartment for storage

Grammatically:

• для takes the genitive case
• хранение becomes хранения

So:

• для хранения = for storing / for storage

Yes. A very literal translation would be cell for storage, but that sounds unnatural in English.

Depending on context, better natural translations might be:

• storage locker
• storage compartment
• storage unit
• deposit box or locker in some public places

Russian often uses more descriptive noun phrases that are translated more idiomatically into English.

Yes, definitely.

Several things make it sound formal or administrative:

• по истечении is a formal expression
• the impersonal нужно is common in notices and regulations
• the whole sentence is concise and rule-like

This sounds like something you might read:

• in a rental agreement
• on a posted notice
• in instructions for locker use

Yes, Russian word order is flexible, but the original order is natural for an official notice.

Original:

• По истечении срока аренды нужно освободить ячейку для хранения.

Possible variation:

• Нужно освободить ячейку для хранения по истечении срока аренды.

Both are grammatical. The original puts the time condition first, which is very common in formal writing:

• When the rental period expires, ...

That said, the original version sounds more polished and official.

The core meaning is upon expiration of the rental term.

In practice, in rules or notices, this often implies that once the term has expired, the storage space must no longer remain occupied. So in real usage, it often carries the practical force of:

• when the rental term ends, you must vacate it
• or even it must be vacated by the end of the rental term

The exact timing depends on context, but the official tone suggests a strict requirement tied to the expiration point.

The main stress points are:

• По истече́нии
• сро́ка
• аре́нды
• ну́жно
• освободи́ть
• яче́йку
• для хране́ния

A rough pronunciation guide:

pa iste-CHÉ-ni-i SRÓ-ka a-RÉN-dy NÚZH-na asva-ba-DÍT' ya-CHÉY-ku dlya khra-NÉ-ni-ya

A few notes:

• по is usually pronounced more like pa
• о in unstressed positions often sounds closer to a
• нужно is pronounced roughly NUZH-na

Yes. A simpler, less formal version would be:

После окончания срока аренды нужно освободить ячейку для хранения.

Or even:

Когда срок аренды закончится, нужно освободить ячейку.

These mean roughly the same thing, but the original sentence sounds more official and notice-like.