Kiam la baterio estas ŝargita, mi denove vidas la ekranon de mia telefono.

Kiam means when. It introduces a time clause: Kiam la baterio estas ŝargita = When the battery is charged.

It appears at the beginning because Esperanto often puts time or condition clauses first, but that is not required. You could also put the main clause first and the meaning would stay basically the same.

The -n marks the direct object. In this sentence, the thing being seen is the screen, so ekrano becomes ekranon.

The verb vidi means to see, and what you see takes -n:

• Mi vidas la ekranon. = I see the screen.

Because telefono is not the direct object of vidas. The direct object is la ekranon.

de mia telefono is a prepositional phrase meaning of my phone. After a preposition like de, you normally do not add -n.

So:

• la ekranon = the thing seen
• de mia telefono = describing which screen it is

Estas ŝargita means is charged or is in a charged state. It describes the battery’s condition after the charging has been completed.

That is different from:

• ŝargas = charges / is charging something
• ŝarĝiĝas = becomes charged / is getting charged

So la baterio estas ŝargita focuses on the result, not the process.

The -it- shows a completed passive participle. From ŝargi = to charge, you get:

• ŝargita = charged, having been charged
• ŝargata = being charged
• ŝargota = about to be charged

So estas ŝargita tells you that the charging has already happened.

Because ŝargita is acting like an adjective. In Esperanto, participles often behave like adjectives.

It describes la baterio, so it takes the adjective ending -a:

• la baterio estas ŝargita = the battery is charged

Since baterio is singular and not accusative, ŝargita stays singular too. If the noun were plural, the participle would also become plural:

• la baterioj estas ŝargitaj

La is the definite article, meaning the. Here it is used because we are talking about specific things: the battery and the screen.

But Esperanto usually does not use la before a possessive like mia, via, ŝia, and so on. So:

• mia telefono = my phone not
• la mia telefono

The possessive already makes the noun definite.

Denove means again.

Its position is fairly flexible in Esperanto. In this sentence, mi denove vidas means I again see or more naturally I can see again. You could also say:

• Mi vidas denove la ekranon de mia telefono.

The version with denove before the verb often emphasizes the return of the action.

Because the sentence is describing a general or current situation: when this condition is true, this is what happens.

Esperanto often uses the present tense in both parts of a sentence like this:

• Kiam la baterio estas ŝargita, mi denove vidas...

If you wanted to describe a past situation, you would change both verbs:

• Kiam la baterio estis ŝargita, mi denove vidis la ekranon de mia telefono.

Yes. de is the normal way to show possession or relationship:

• la ekrano de mia telefono = the screen of my phone

You could also say:

• mia telefona ekrano

That means something like my phone screen. Both are natural, though la ekrano de mia telefono may feel a bit more straightforward for learners.

Yes. Esperanto word order is fairly flexible, although some orders sound more natural than others.

For example, you could say:

• Mi denove vidas la ekranon de mia telefono, kiam la baterio estas ŝargita.

That is understandable, but starting with Kiam... is often nicer because it sets up the condition first. Esperanto uses word order more for emphasis and style than for basic grammar, since endings like -n already show the roles of words.

It means the battery is already charged. The phrase estas ŝargita describes the resulting state.

If you wanted to say the battery is in the middle of being charged, you would use:

• la baterio estas ŝargata = the battery is being charged

So this sentence is about what happens once the battery has charge, not during the charging process.