Learn Hardcore Italian: Gli altoparlanti portatili si scaricano in fretta, ricòrdati di ricaricarli. - Portable speakers run out of battery quickly; remember to recharge them.

i is used before consonant-initial words (e.g. i libri).
gli is used before vowel-initial words or certain consonant clusters (e.g. gli amici, gli studenti, gli altoparlanti).
Since altoparlanti begins with a vowel, you need gli altoparlanti.

What does si scaricano mean, and what role does si play?

Here scaricarsi is a pronominal (reflexive) form of scaricare:

scaricare = “to unload,” “to download,” or “to discharge” (transitive).
scaricarsi = “to discharge itself,” i.e. “to run out of power/charge” (intransitive).
The si marks that the subject (the speakers) is acting on itself (themselves losing charge).

Why is the pronoun si placed before scaricano, rather than attached?

Pronoun placement depends on the verb form:

With a conjugated verb, pronouns go before: si scaricano, ci sentiamo, ti vedi.
With an infinitive, imperative or gerund, pronouns attach after as enclitics: scaricarsi, ricaricali, scaricandosi.
Here scaricano is a conjugated form, so si precedes it.

Why is the adjective portatili placed after altoparlanti, and is its ending the same for masculine and feminine?

Word order: In Italian, most descriptive adjectives follow the noun: altoparlanti portatili rather than portatili altoparlanti.
Ending: portatile is an –e adjective in the singular, so its plural (both masc. and fem.) is portatili:
- il computer portatile → i computer portatili
- la radio portatile → le radio portatili

Why is in fretta placed after scaricano, and could I use velocemente instead?

in fretta is an adverbial phrase meaning “quickly,” and it naturally follows the verb: si scaricano in fretta.
You can also say si scaricano velocemente. Both mean “they run down quickly,” but: • in fretta is more colloquial/conversational.
• velocemente is a formal adverb of manner.

Why is the imperative ricordati used instead of ricorda, and what’s special about the pronominal form?

ricordarsi = “to remember” (something for yourself).
ricordare (without si) = “to remind” (someone else).
To tell someone “remember (for yourself),” you need the 2nd p.s. imperative of the pronominal verb: ricordati.
Using ricorda alone would mean “remind (someone else).”

Why does ricòrdati have an accent on ò, and is it mandatory in writing?

The accent on ricòrdati is not part of standard spelling—it’s added here purely to show that the stress falls on the “ò.” In normal texts you simply write ricordati, without an accent.

Why is di necessary after ricordati in ricordati di ricaricarli?

The pronominal verb ricordarsi requires the preposition di before another verb in the infinitive. The pattern is: ricordarsi di + [infinito] So ricordati di ricaricarli = “remember to recharge them.” Omitting di would be ungrammatical.

Why is li attached at the end of ricaricarli rather than placed before the verb?

With an infinitive, object pronouns attach as enclitics.

ricaricare + li ⇒ ricaricarli
In contrast, if you conjugate the verb you place the pronoun before: li ricarico (“I recharge them”).