I'm not sure if this has been discussed here before. But I've noticed some LEGO sets have a "light brick". As far as I can tell, these are bricks with a light and a battery in them. Sets with a light brick include "The Orc Forge" (9476), "Whitecap Bay" (4194), and it appears the new "Winter Village Cottage" (10229), among others. I don't have any light brick sets so I'm not familiar with them. My question is, does a light brick in a set effect the investment value at all? Is it a good feature short and long term? Is it possible for the battery to corrode/leak and damage the set, especially if stored for the longer term? Any comments? Similarly, I wonder if Power Function batteries (e.***. in Technic sets) can have a problem with corroding/leaking if stored for a long time.

Not sure about the investment impact ... and like you, I haven't come across them that often, but in the sets where I have, the light bricks come with the little plastic piece that prevents touching between the battery and the contact. As long as that doesn't get removed it should go a long way to preventing corrosion... I might be wrong though ??

If the set has a battery it will eventually corrode even if there is a barrier between the battery in the contact. I have had many discussions about batteries in toys and there is only once conclusion...they will corrode. Now the time it takes can depend several factors (mostly temperature). Good thing about legos is that if the piece corrodes, you should be able to replace it without buying the set again. This is not the case for other toys (transformers).

Good question. I find that most sets with some sort of light up bricks or minifigures are popular. They might not be the best investments, but I don't think the light up bricks hurt values. They probably raise values tp a small degree in that it is a "special" feature. I find the batteries last a long time. I have a light up Lando Calrissian from ten years ago and the light saber still works, but I never tried replacing a battery.

A lot of my light bricks from the Exo-Force theme don't work anymore. Is it possible to replace 'em?

I find the batteries last a long time. I have a light up Lando Calrissian from ten years ago and the light saber still works, but I never tried replacing a battery.

Lando never came with a lightsaber. In fact, he never even had a lightsaber in the movies! I'm assuming the minifig you're talking about is Mace Windu. There was a Mace Windu minifig with a light-up purple lightsaber a few years back.

A lot of my light bricks from the Exo-Force theme don't work anymore. Is it possible to replace 'em?

Lando never came with a lightsaber. In fact, he never even had a lightsaber in the movies! I'm assuming the minifig you're talking about is Mace Windu. There was a Mace Windu minifig with a light-up purple lightsaber a few years back.Yes..My bad. You are correct.