I was asking someone about leds for armada and I mentioned what I had seen on here. Here was his repsonse

Those blue and White leds run at about 15-20 milliamps each. This is a current rating, and states that if you test the circuit, your meter will read 20/1000’s of an amp. Pretty small. The CR2032 watch battery was designed for 0.5 milliamp discharge rate. The ships those guys were lighting were using 8-10 LED’s. It doesn’t take long to add up the current requirement for those circuits and you are near a 100 milliamp discharge rate. The total battery capacity of those CR2032’s is only about 250 mah. MAH means milliamp-hours, or if it was rated at 250 mah, it could supply 250 milliamps for one hour, or 1 milliamp for 250 hours. If you can imagine a graph, with those two points and a line between them representing current and time. Anyways, that rating is not technically accurate because of the 0.5 milliamp/hour max discharge rate limit.
If you tried to run 250 milliamps for 1 hour, you would overheat the battery and possibly explode it. That is the danger here. ANY circuit using those batteries could overheat and damage the ship or leak acid. Both are bad scenarios.
AAA and AA batteries are much more safe with much higher discharge rates and much larger capacities. But they are only 1.5 volts, so you need more of them to run LED’s. And they are bigger, so you can’t squeeze them into the same small places.
So, while these watch batteries probably won’t explode, they very well will overheat if you use them like those guys did. Plus, with 9 or so LED’s , you would literally only get about 1.5 hours out of each battery. And it would be different each time based on the quality of the battery and how long it has been on the shelf. If you went with the AA or AAA batteries, you would get many hours out of each set of batteries depending on how the circuit was designed.

Can anyone speak to this that has made an LED mod to their ship.

What model needs nine LEDs at once?

I have not modded my ships with LED so far, but he is right in term of the battery and the LEDs. Unless you use low current LEDs with only 1-2 mA, you will drain the CR2032 battery in no time. The danger of overheat might another part. Even when i dont think they might explode, they will still heat up quite a bit.
I made a line laser pointer with 2x 15mA laser modules. And i used 2x AAA batteries for the supply for these as well.

The problem is the white and blue LED start at 20 mA (at least the typical one). You can get low power ones (1-2 mA) far easier in red and green, but not in white and blue.

So if you want to mod your ship with blue and white LEDs, make sure to have the room for at least 2 AAA batteries. Or similar ones. There are special batteries that are a little bit smaller than AAA and still have enough power and a "typical drain" (discharge rate) to supply 9 LEDs. There are even some that you can put on the downside of the ISD base, if you dont want to put the batteries in the ship.
If you are using AAA ones, they are to big for the ship base.

I'm not to knowledgeable on electricity, but what if you set up the batteries underneath the ship base and ran wires up the fin and had a metal connection at the keyhole? So your on/off is when you put the model together or take it apart. You could do another connection at the base so you can take off the fin to flip the card. It would allow you to have multiple ship set ups and easy swapping of bases and fins. And you can access the batteries.

Undead- You could do that, but it is infinitely more complex. Would certainly make changing batteries easy though, and momentary switches (the kind you would recess in the keyhole so the lights are only "ON" when there is something depressing it) are far cheaper and get far smaller than locking switches.

I have my lighted ISD linked to a 9v battery. About the same size as 2 AA, little smaller length wise, and was easier to manage as one piece. However, it would have been nice to run 1 AA battery on each side of the keyhole. I had to do some pretty extensive interior space clearing to get mine to snap back together. I put 3 mags on each half of the ISD so it just clicks back in place, so I can turn it off, change batteries, mod the LED's or whatever with relative ease. I have been meaning to take pictures of all my mods but I have had so little evening time with children and my days have been filled from 7 am to 7 pm with work.

I used this in my ISD's and add resistors to some of the LED's so they're not so eye-searingly bright:

https://www.sparkfun.com/products/11259

This guy fits well inside an ISD, That being said, running engine lights, as well as window lights it's really only good for about a few hours before it visibly begins to dim.

I have no idea what amperage my LEDs have but I've never noticed both overheating or super fast power drainage. LEDS in my models- mostly in ISD- are running non-stop during the tournaments and I haven't replaced CR2032 yet (we are talking about 8-10 events 8-10h each). My methods (and knowledge) is far from professional however so don't take any risks with that and secure Your models (and health!) as suggested above

BTW I went to far with LEDs now (ISD, VSD, GSD and Interdictor) so I can't deploy all this models in a single fleet :/

Undeadguy's suggestion would work even better if you simply add a connector (USB or reclaimed PC stuff would be perfect for this, and there's loads of simple rechargeable USB dohickeys in existence?) near the keyhole, rather than try to engineer the keyhole itself? That's what I'd probably do, if I were so inclined, and gives you more space to fit your light sources/removes the preserving wattage concern. Also adds some weight to the base and allows you to observe the tournament rule of removing colliding models (not bases!)...

Anyone think that'd be worth a shot?

Current limiting resistor, thats my solution. I typically put two of those watch batteries in series with eachother and in series with a resistor and the LED's parallel with eachother. If i recall correctly i don't feed them the full 20mA so i can get away with it. Although the original poster may be right, in my experience I have not had problems with overheating or short battery life so there must be more to this problem than was originally suggested. I'll take some measurements next time i pop them open and tell you how much current is running through them.