I am a Ping abuser. I have a 48V20aH v2 that I am trying to kill, or more accurately, I just want to have fun and am running the heck out of it. I run a Crystalyte 5303 and a Crystalyte 48V35A controller on an upright mountain bike. My CA indicates 1500 watts (35-40A, ~2C) continuous. In the city on short (10 mile) trips I use 30-35 Wh/mile with 40MPH max and average speed around 25MPH. I have about 2100 miles and probably 250 cycles.
I had issues with the high current cutout on the BMS so I wired around it. I set a voltage cutoff of 41 volts on the CA and, testing with the BMS in-line, the CA cuts out before the BMS. I may get a cell that goes out and this method may not catch it but the cell is dead and needs replacement anyway - trying to save it is useless. I check individual cell voltages compulsively so I hope to avoid a cell that drifts out of balance.
I use a Soneil 4808SRF SLA charger adjusted to 60.8. It does have balancing issues. I saw a dramatic decrease in capacity charging at 58.9V and had the problems go away when I bumped to 60.8V. I do not run it down very often. I need to take a 30+ mile ride to check total capacity. The most I have seen is about 17aH after 31 miles. I have some single cell chargers coming and will top everything off then give it a range test. Running high current output, balance is the issue. I will try the Ping charger I got with the battery to see if it has a better charge curve to allow balancing but it has such a low output voltage that I doubt it will do better.
My impressions after 2100 miles is that Ping ROCKS. If you need a full 20aH at 30+ amps, you may need to go Headway or tool packs or if you are anal about life expectancy and will scream if you don't have 85% at 1000 cycles, keep the output at 1C, but if you are satisfied with 15-18aH and think the battery is expandable and will need replacing when it needs replacing, disconnect the BMS on discharge and ROLL. That being said, other than when it went out of balance, the battery still seems about as strong as new. I never really tested it well enough to know if it ever put out a full 20aH at the load levels I run but even 15 is enough for my normal rides. If I don't have a catastrophe, I expect this battery to last at least another year - another 2500 miles - and it may not even get the chance. I have a48V10aH Headway on order from EVComponents and am in corresponance with Ping on a v3 48V20aH. The only reason I am looking for another battery is because I think I want to go to 50-60A continuous and this battery would melt down at those rates - I am into abuse but I guess out-and-out murder IS beyond me. It already gets pretty hot in the bag and I think it is bouncing around quite a bit too.
I will update again at about 3000 miles (mid September?)...