Figure 1: end of charge voltage vs cycle life Effect of CV charge voltage on cycle performance Test cells charged at constant current at 1C rate to cut-off voltage followed by CV float charging at this voltage for 2.5 h and then discharged to 2.75 V at 1C rate. (Red line added to show reference loss @ 4.2V after 500 cycles.) (Choi, 2002)
Figure 2: end of discharge voltage vs cycle life Effect of discharge cut-off voltage (essentially depth-of-discharge) on cycle performance. Test cells charged by constant current at 1C rate to 4.2V followed by CV float charging at 4.2 V to 90 mA current cut-off and then discharged to specified discharge cut-off voltage. (Choi, 2002)