BentHeadTX
Flashlight Enthusiast
I've done a lot of testing on the PowerEx 2700mAH AA cells as I have twelve of them. Four are in use and the other 8 are "matched" cells sitting quietly in a 8 cell holder. After running forming charges on a Cadex (they call it extended prime) and other various forms of testing they have about 7 cycles on them.
The big test was to see self discharge rates on the entire pack of 8 cells. The Cadex will do a 24 hour self discharge test which I did on one of the other cells in use and it returned a 6% self-discharge in one day. Since I am not using the cells presently, I decided that I could do a self discharge test to see how well they performed after a month of laying around.
The PowerEx batteries were treated to a two-cycle charge/discharge rate of C/10 charge and C/5 discharge set up as a 9.6V series pack. The discharge limit under load was 1.00V and charge cutoff was set at .08V per cell of voltage depression. The temp cutoff was 45C and the test was done with a room temp of 22C.
32 days later, I set up the Cadex 7400ER analyzer to discharge at a C/5 rate (540mA) with voltage cutoff of 1.00V per cell. The test returned a reading of 81% which is a drop of 18% from the initial 99% capacity reading. Or, to put it in mAH readings; intially it gave a reading of 2673mAH and dropped to 2187mAH.
Overall, I am very pleased with the PowerEx 2700's as they have a much lower self discharge rate than the PowerEx, Energizer and Sony 2500's (Sanyo HR stamp on all of them) Those 2500's would be very close to dead after 32 days so the 2700's are a big improvement.
Remember that those 8 cells were charged / discharged in a 8 pack in series so the worse battery would lower the results. Initially they were done seperately but now live and die together as a battery pack. Since the only thing these batteries have done is testing and cycling, it is probably the best case scenario for them but I'll use them eventually in a 8AA to 2D Mag mod.
Any questions?
The big test was to see self discharge rates on the entire pack of 8 cells. The Cadex will do a 24 hour self discharge test which I did on one of the other cells in use and it returned a 6% self-discharge in one day. Since I am not using the cells presently, I decided that I could do a self discharge test to see how well they performed after a month of laying around.
The PowerEx batteries were treated to a two-cycle charge/discharge rate of C/10 charge and C/5 discharge set up as a 9.6V series pack. The discharge limit under load was 1.00V and charge cutoff was set at .08V per cell of voltage depression. The temp cutoff was 45C and the test was done with a room temp of 22C.
32 days later, I set up the Cadex 7400ER analyzer to discharge at a C/5 rate (540mA) with voltage cutoff of 1.00V per cell. The test returned a reading of 81% which is a drop of 18% from the initial 99% capacity reading. Or, to put it in mAH readings; intially it gave a reading of 2673mAH and dropped to 2187mAH.
Overall, I am very pleased with the PowerEx 2700's as they have a much lower self discharge rate than the PowerEx, Energizer and Sony 2500's (Sanyo HR stamp on all of them) Those 2500's would be very close to dead after 32 days so the 2700's are a big improvement.
Remember that those 8 cells were charged / discharged in a 8 pack in series so the worse battery would lower the results. Initially they were done seperately but now live and die together as a battery pack. Since the only thing these batteries have done is testing and cycling, it is probably the best case scenario for them but I'll use them eventually in a 8AA to 2D Mag mod.
Any questions?
Last edited: