I got IB's that I had since last year that are still takin on anywhere from 4100 to 4300 mah's. I do have a routine that I follow and maybe that is why my packs are doing so well. I don't run mod either so that could be another factor as well. I discharge after I run, equalize and put in the box till next time. I then equalize again then charge them. If sitting for longer then a week I will run them on my Spintec and Dyna Pulse before charging.