Having issues with my “top of the line” 4s lipos. One cell seems to go dead in all of them. Bought 3 6500 and 3 5200 zappers and all of them are now DEAD? Lost 5 of the 6 to a dead cell and finally tonight the last one puffed and broke the case. I don’t feel that they lasted near as long as my old batteries even though I always treated these way better. Always used the charger to put in storage mode after every race and never left them charged over night. My old batteries I just left them wherever they were at the end of the run and used them 4-5 years. They were a low C battery and I decided that when I got serious about racing I would buy the “better” battery. Well it seems the theory is better doesn’t make it last longer. So any suggestions on a good 4s lipo?