friedwires
100 W
so i took a chance and bought this battery condition unknown. http://endless-sphere.com/forums/viewtopic.php?f=9&t=34397
The battery was shipped right away and it showed up sooner than expected. the first thing i noticed when comparing the battery to the one on the test thread was that this is the same exact battery that DocBass had tested back in 2009. I also noticed that the enclosure is in pretty rough shape, its got a few shipping miles on it.
i went ahead and measured voltage on the charge and discharge plugs,and read barely over 9v on each, i also measured at cell level, the highest being 2.2v, and the lowest being 0.00 with several being under 1.0v. i changed out the charge port to a 3-pin xlr and hooked up a 2.5a 60v sla charger and it would'nt take the charge. i did some more measuring and found that the pack voltage was 19.5 actually twice the voltage that was reading on the charge and discharge plugs. other than soldering terminals and doing instalations,i have no experience with lithium batteries. so far its just been plug and play for me. There is definately something up with the bms so i bypassed it and got the charger to turn on. i let it run for a couple hours till i got a voltage of 52.5v. i let it settle a bit then i connected 2 300w light bulbs directly to the pack and discharged to 47v or so and repeated the process three times. i tried to discharge through the discharge plug,but once the load was put on it the voltage on the plug went to zero. here are the cell readings from last night about 15 minutes after charge
3.32 3.32 3.32 3.31
3.30 3.30 3.30 2.95 52.5v
3.32 3.32 3.32 3.32
3.30 3.30 3.30 3.22
and here are the readings after resting overnight
3.29 3.29 3.29 3.28
3.28 3.29 3.29 0.88 50.0v
3.29 3.29 3.29 3.29
3.29 3.29 3.29 3.07
one thing i did notice while discharging was the low cell would actually reverse polarity only a couple minutes into discharging, i imagine that one is junk. i'm also still measuring only half of the pack voltage at the charge and discharge ports, i'd like to just pitch that stupid bms and run the battery without it. will these cells self ballance? and when should i stop the charge? is 3.32 enough?
The battery was shipped right away and it showed up sooner than expected. the first thing i noticed when comparing the battery to the one on the test thread was that this is the same exact battery that DocBass had tested back in 2009. I also noticed that the enclosure is in pretty rough shape, its got a few shipping miles on it.
i went ahead and measured voltage on the charge and discharge plugs,and read barely over 9v on each, i also measured at cell level, the highest being 2.2v, and the lowest being 0.00 with several being under 1.0v. i changed out the charge port to a 3-pin xlr and hooked up a 2.5a 60v sla charger and it would'nt take the charge. i did some more measuring and found that the pack voltage was 19.5 actually twice the voltage that was reading on the charge and discharge plugs. other than soldering terminals and doing instalations,i have no experience with lithium batteries. so far its just been plug and play for me. There is definately something up with the bms so i bypassed it and got the charger to turn on. i let it run for a couple hours till i got a voltage of 52.5v. i let it settle a bit then i connected 2 300w light bulbs directly to the pack and discharged to 47v or so and repeated the process three times. i tried to discharge through the discharge plug,but once the load was put on it the voltage on the plug went to zero. here are the cell readings from last night about 15 minutes after charge
3.32 3.32 3.32 3.31
3.30 3.30 3.30 2.95 52.5v
3.32 3.32 3.32 3.32
3.30 3.30 3.30 3.22
and here are the readings after resting overnight
3.29 3.29 3.29 3.28
3.28 3.29 3.29 0.88 50.0v
3.29 3.29 3.29 3.29
3.29 3.29 3.29 3.07
one thing i did notice while discharging was the low cell would actually reverse polarity only a couple minutes into discharging, i imagine that one is junk. i'm also still measuring only half of the pack voltage at the charge and discharge ports, i'd like to just pitch that stupid bms and run the battery without it. will these cells self ballance? and when should i stop the charge? is 3.32 enough?