I bought a 5s and 4s pack about a year ago or so and ended up shelving them. About a half year ago or so I noticed the 5s pack puffed . I reached out to Steve @ OSE and he told me to send it back to him . Anyway I got busy with life and never did send it . Now I finally have time for boats and trying to get back to the hobby . I know there was a issue with my 5s pack but now the issue is with the 4s. 4s pack reads zero volts!! ... I thought Lipo’s could be stored for several years with minimal deterioration like my Zippy’s that have been battlefield tested and why they may not be as powerful as the Graphin type they don’t crater when not in use as I have noticed putting them into service from a year of sitting on the shelf and then back to the shelf , they seem like the perfect battery for somebody who is off and on with the hobby. Now the Graphin 4s pack seems totally dead and not puffed while the 5s Graphin pack is talking a different language that my volt tester, I mean when I reached out to OSE with the dead cell issue on the 5s he said send it back , but I didn’t just because I got caught up with life . I don’t really care about a refund or an exchange, I just need to know the skinny on the shelf life. For all I know these are really good pack and I ruined them by not using them . All my 8000mah 30c zippy packs are fine. Thank you for the comments 05A4D235-292D-417C-AA9B-08D2077EA877.jpg1177019B-6348-45D8-89F4-EF15DD014BEE.jpg5CFD7D58-1AB7-4E0D-9029-421245EC343F.jpg