Guardamos el cargador portátil y las pilas de repuesto.

Guardamos comes from the verb guardar, which often means to keep, to store, to put away, or to save, depending on context.

In this sentence, it most naturally means something like we put away or we stored.

Some common uses of guardar:

• guardar ropa = to put away clothes
• guardar algo en una caja = to store something in a box
• guardar silencio = to keep quiet

Spanish often leaves out subject pronouns when they are not needed. The ending of the verb already shows who is doing the action.

• guardamos = we keep / we put away / we stored

So:

• Guardamos el cargador... = We put away the charger...
• Nosotros guardamos el cargador... = also possible, but nosotros is usually only added for emphasis or contrast.

Yes. Guardamos is one of those forms that can be:

• present tense: we keep / we put away
• preterite: we put away / we stored

So the exact time can depend on context.

For example:

• Cada noche guardamos el cargador. = Every night we put away the charger.
  → present / habitual
• Ayer guardamos el cargador. = Yesterday we put away the charger.
  → past

In Spanish, adjectives usually come after the noun.

So:

• el cargador portátil = the portable charger

This is the normal word order:

• una batería externa
• una funda negra
• un teléfono nuevo

Sometimes adjectives can go before the noun, but that usually changes the tone or meaning. With portátil, the normal position here is after the noun.

Literally, it means portable charger.

Depending on context, it could refer to:

• a charger that is easy to carry around, or
• very often, a power bank

In everyday modern usage, many people would understand cargador portátil as a portable device used to charge a phone or other device while away from a plug.

In Spain, pila and batería are not always used in the same way as battery in English.

A useful general guide:

• pilas = small removable batteries, like AA or AAA batteries
• batería = rechargeable battery pack, phone battery, car battery, drum kit, etc.

So:

• pilas de repuesto = spare batteries
• la batería del móvil = the phone battery

In this sentence, pilas suggests ordinary replaceable batteries.

De repuesto means spare, replacement, or extra to use when needed.

So:

• pilas de repuesto = spare batteries
• rueda de repuesto = spare tyre
• piezas de repuesto = spare parts

It does not change to match number in the way a normal adjective often would. It is a fixed phrase:

• pila de repuesto
• pilas de repuesto

So even though pilas is plural, de repuesto stays the same.

Spanish usually uses definite articles more often than English does.

Here:

• el cargador portátil = the portable charger
• las pilas de repuesto = the spare batteries

The articles agree with the nouns:

• el for singular masculine noun: el cargador
• las for plural feminine noun: las pilas

Even if English might sometimes say something more generally, Spanish often still prefers the article.

Yes. Pila is a feminine noun.

So the forms are:

• la pila
• las pilas

That is why the sentence says:

• las pilas de repuesto

By contrast:

• el cargador
• los cargadores

In the singular, portátil stays the same for both masculine and feminine nouns:

• el cargador portátil
• la consola portátil

What changes is the article, not the adjective.

In the plural, it becomes:

• portátiles

For example:

• los cargadores portátiles
• las consolas portátiles

Because las pilas de repuesto is the direct object, and it refers to things, not people.

Spanish uses the personal a mainly before specific human direct objects.

Compare:

• Guardamos las pilas. = We put away the batteries.
  → no a
• Vemos a María. = We see María.
  → a because María is a person

So here, no a is needed.

Yes, but the given order is the most natural neutral one.

Normal order:

• Guardamos el cargador portátil y las pilas de repuesto.

You could change the order for emphasis, for example:

• Las pilas de repuesto y el cargador portátil los guardamos aquí.

But for a simple statement, the original version sounds most natural.

Here it is more like to put away or to store.

The verb guardar can sometimes be translated as to save, but that depends on context. For example:

• Guardar dinero = to save money
• Guardar un archivo = to save a file
• Guardar los juguetes = to put away the toys

In this sentence, because we are talking about physical objects like a charger and batteries, put away or store is the best fit.