The way you wired the LED is correct for the econoboard.
The LED positive goes to the battery positive and the LED negative goes to the LED output on the board.

The problem is that the econoboard was engineered to drive 3 or 4 standard LEDs, so it is not giving much current at all.
To increase the current to the LED we normally use the PNP transistor wired as shown in this thread:

http://forums.thecustomsabershop.com...ght=econoboard

The thread is veeery long, but you can stick with the diagrams in the first post, they are correct.

The transistor you need is a TIP42C or equivalent.
It can give you all the current you need or, in other words, it can give you all the current your batteries are able to provide