Help settle an argument please.  

I think it will work in a wall outlet. My stepdaughter used to sometimes plug it in that way. It is still a good idea to charge the battery too though.

I think it depends on the laptop, but I have run mine without the battery connected, just through the wall outlet.

I cant speak for all laptops but if I just plugged mine into the wall it would work without the battery being charged.

Sure. As long as it is plugged in, the battery does nothing but charge.

I have used my laptop with the battery removed before with no issues.

The battery is just a cordless way of using a laptop for a while but isn't necessary if you have an outlet nearby.

Answering from email so you probably got 100 of the same answers. Apologies if I repeated what others may have said.

It does indeed depend on the laptop. Some are able to run without the battery and just plugged in, but I remember others need the batter plugged in as part of the power component.

I think it works that way, even with a Mac. I'm on a Mac, but I don't recall if it did work without a battery the last time I removed it and just kept the power plug/adapter on.. But I do know that with PC laptops, the computers work fine without the battery, just the AC adapter.