14 months (6K miles) using 36 REAL FORCE 120 AH LiFEPO4 cells. Generally good results, but I'm having serious range problems now. I'm using Dimitri's mini bms so it's difficult to determine which cell is causing LV alarms but they now start at a little less than 20 miles, I'm doing most of my driving very gently at only about 100 Amps (sometimes less). Mostly at 35 MPH or less, only short excursions above 45 and this is Florida -- almost no hills. The pack has been top balanced again and again to the point that static (after driving) voltages are all within .03V of average cell voltage and highest voltage - lowest voltage is around 0.1 V after a day of driving. The lowest cell seems to change every time I measure cell voltages. For a while I was suspecting cell #6, then it was #30, then #5, and most recently it was #21. It's not at all easy to observe the LED's on the cells while driving so all I can really do is static voltage measurements after I get home. Obviously, something is amiss with my batteries but I need some sort of test procedure to determine what the solution is. Do I have to replace all 36 after only 14 months? I have never charged any cells above about 3.8V and only once have I measured a cell voltage below about 2.5V. If one is damaged, it doesn't consistently show up as way different from the rest. When I first completed the project, I could go 62 miles on a charge. Now the audible alarms start at around 19 miles. Anybody have an idea of what the fix is?