hoeuisil byeoge issneun konsenteue chungjeonseoneul kkojassneundedo baeteoriga jal an chasseoyo.

They are doing two different jobs.

1. 벽에 있는

   • Here, 에 marks the location of 있는:
     있는 = that is located / that exists
   • So 벽에 있는 콘센트 means the outlet that is on the wall.

2. 콘센트에

   • Here, 에 marks the place/destination where something is inserted.
   • 충전선을 콘센트에 꽂다 = to plug a charging cable into an outlet

So the phrase breaks down like this:

• 회의실 = meeting room
• 벽에 있는 = that is on the wall
• 콘센트에 = into the outlet

Altogether: into the outlet on the meeting room wall.

This is a very common Korean noun-modifying structure.

• 있다 = to exist, to be located
• 있는 = existing / located / that is

So:

• 벽에 있는 콘센트 = the outlet that is on the wall

Korean often puts a verb before a noun to describe it:

• 책상 위에 있는 책 = the book that is on the desk
• 밖에 있는 사람 = the person who is outside
• 회의실 벽에 있는 콘센트 = the outlet that is on the meeting room wall

So 있는 is directly modifying 콘센트.

꽂았는데도 means even though I plugged it in or despite plugging it in.

It can be broken down like this:

• 꽂다 = to stick in, insert, plug in
• 꽂았- = past tense stem, plugged in
• -는데도 = even though / despite the fact that

So:

• 충전선을 꽂았는데도 = even though I plugged in the charging cable

This ending is used when the result goes against expectation.

Example idea:

• You plugged it in, so you would expect it to charge.
• But it did not charge well.
• That mismatch is exactly what -는데도 expresses.

-는데 often just connects two ideas:

• background
• contrast
• soft explanation

-는데도 is stronger and means:

• even though
• despite the fact that

Compare:

• 충전선을 꽂았는데 배터리가 안 찼어요.
  = I plugged in the cable, but the battery didn’t charge.

• 충전선을 꽂았는데도 배터리가 안 찼어요.
  = Even though I plugged in the cable, the battery didn’t charge.

The second one emphasizes that the result is surprising or contrary to what should have happened.

Because 차다 here is functioning like an intransitive verb.

• 차다 = to fill up / become full / get charged
• The battery is the thing that becomes full
• So 배터리 takes 가/이, not 를/을

That is why:

• 배터리가 찼어요 = the battery charged / became full
• 배터리가 잘 안 찼어요 = the battery didn’t charge well

A useful comparison:

• 배터리를 충전했어요 = I charged the battery
  → transitive, so 배터리를
• 배터리가 충전됐어요 / 배터리가 찼어요 = the battery got charged
  → intransitive/result state, so 배터리가

잘 안 + verb is a very common pattern in Korean.

It often means:

• doesn’t work well
• doesn’t happen properly
• doesn’t do much
• not very successfully

So here:

• 잘 찼어요 would mean it charged well
• 잘 안 찼어요 means it didn’t charge well / it barely charged

The 잘 does not always mean only well in a positive sense. With 안, it often means not properly or not much.

Examples:

• 잠이 잘 안 와요. = I can’t fall asleep easily.
• 문이 잘 안 열려요. = The door doesn’t open well.
• 인터넷이 잘 안 돼요. = The internet isn’t working well.

So in your sentence, 배터리가 잘 안 찼어요 suggests the battery charged poorly, slowly, or barely at all.

Because the speaker is talking about the result after some time had passed.

They are not describing the charging process in real time. They are saying something like:

• I plugged it in,
• but afterward,
• the battery did not end up charging well.

So 안 찼어요 reflects the outcome.

Compare:

• 배터리가 잘 안 차요.
  = The battery doesn’t charge well.
  This sounds more like a general/habitual statement.

• 배터리가 잘 안 찼어요.
  = The battery didn’t charge well.
  This refers to a specific past situation.

충전선 means charging cable.

• 충전 = charging
• 선 = line, wire, cable

So 충전선을 꽂다 means to plug in the charging cable.

By contrast, 충전기 usually means:

• charger
• the charging device/adaptor itself

In everyday speech, people may use these a little loosely depending on context, but the basic distinction is:

• 충전선 = cable
• 충전기 = charger/adaptor/device

So this sentence specifically says the speaker plugged in the cable to the outlet.

콘센트 is a loanword, originally from a foreign source via Japanese usage, and in modern Korean it means electrical outlet / socket.

So:

• 콘센트에 꽂다 = to plug into an outlet

A native English speaker may expect a word closer to outlet or socket, but in Korean 콘센트 is the normal everyday word.

Korean commonly stacks descriptive information before the noun and leaves the main action for later.

Here is the structure:

• 회의실 = meeting room
• 벽에 있는 = that is on the wall
• 콘센트에 = into the outlet
• 충전선을 = the charging cable
• 꽂았는데도 = even though I plugged it in
• 배터리가 잘 안 찼어요 = the battery didn’t charge well

A very literal order would feel like:

• Meeting-room wall-on existing outlet-into charging-cable plugged-even-though battery-NOM well not filled

That sounds strange in English, but it is natural in Korean because Korean builds up context first and gives the main result near the end.

Yes. A very natural alternative would be:

• 회의실 벽에 있는 콘센트에 충전선을 꽂았는데도 배터리가 잘 충전되지 않았어요.

This means almost the same thing:

• the battery didn’t charge well
• the battery didn’t get charged properly

The difference is mostly in feel:

• 배터리가 잘 안 찼어요
  = more everyday, more like the battery didn’t fill up/charge well

• 배터리가 잘 충전되지 않았어요
  = slightly more formal or technical, more explicitly was not charged

Both are correct and natural.

Yes. It sounds natural and everyday.

In speech, Koreans often prefer simpler, more direct verbs when talking about ordinary situations. 차다 for a battery is a good example of that.

So:

• 배터리가 안 찼어요 sounds conversational and common
• 배터리가 충전되지 않았어요 sounds a bit more formal or explanatory

If you are speaking casually about phone charging, 차다 is very useful to know.