OK,
I don't know if you guys know about these but here's a link to pete's site where he sells
Solderless Battery Tubes
These packs are great! If a single cell goes bad, its easy to replace it.
So, you could buy loose IB cells from mike and simply make a pack with NO SOLDER. I use these packs with GP 3700's and 2200's and beat nitros all day long :D
As long as the IB's are the same diameter as the GP's, they'll fit fine.