Since day one the end cells in my ping pack where always the most stubborn to balance. They did this on the ping charger, an imax b8 and my cellpro10s.
I have also read that if a cell is going to die its most often the one at the end (at least from high discharge rates).
I didnt like pings charger (for no tried and tested reason) other than it kept bouncing the cells to 3.9v when balancing. This could take 6 hours so decided to wire a connector for a cellpro10s charger and have never looked back. I can charge at 4ah through my pig tails only or 10ah down the main charge leads (although I never need above 4ah anyway and never go higher).
The pack now balances in 30 minutes max. I can now turn the charger on the same morning im going to need it without worry of it not getting fully charged. It charges perfectly to 3.42v where the cells all start to wander off unevenly, then 30 mins later they are all at 3.64 and never goes anywhere near 3.9v.
I also removed the bms to reduce any current loss in it both while sat and running. The bms also seemed to drag down 4 cells (I guess it needs 12v to operate) meaning I would have to unplug it every time I left it unused for a few weeks. This never made a huge difference but I believed it was helping bring the pack out of balance and prolong the agony of wanting my bike fully charged to ride while the ping charger slowly balanced the pack. I often notice say 1-4 cells at 3.30v and cells 4-8 at 3.48v although in ah terms it would prob be 0.2ah max. I guess this is why Ping supplies the bms unplugged now as it is in transit for weeks.
I now have a voltage alarm set to 3.0v which means I have around 2ah left maybe and to start pedalling harder when it beeps rather than suddenly have the bms cut out and have to push a hub motor 5 miles home lol. The bike seems to feel more lively right till the end now the current isnt passing through the bms circuits. Before removing it I noticed a slight drop in performance near the last quarter of the packs life. Maybe this is just psychological lol.
For me I have extra heavy duty charge sense wires fitted but to the average ping owner im sure you can use the bms sense wires combined with the two main charge leads to get your alarm working on every cell. The reason I have extra leads mainly was to use my cellpro10 charger to charge via its pig tail connectors only. No disconnecting of the packs main leads is now needed for this set up.
The cellpro10s is the Best £100 Iv spent so far to make my EV life smoother and can now charge a bunch of lithiums for other projects like lights etc . The imax 8 has 300mah bleed current and the ping bms is likely to bleed off even less only working by turning the charger on and off according to cells hitting high voltage then waiting to be slowly drained down. The cellpro charger boasts 1 amp equalising bleed drain and can confirm this is at least 5 times faster than the ping charger and imax 8 at balancing
http://s1239.photobucket.com/albums/ff506/bionicdan/
I have also read that if a cell is going to die its most often the one at the end (at least from high discharge rates).
I didnt like pings charger (for no tried and tested reason) other than it kept bouncing the cells to 3.9v when balancing. This could take 6 hours so decided to wire a connector for a cellpro10s charger and have never looked back. I can charge at 4ah through my pig tails only or 10ah down the main charge leads (although I never need above 4ah anyway and never go higher).
The pack now balances in 30 minutes max. I can now turn the charger on the same morning im going to need it without worry of it not getting fully charged. It charges perfectly to 3.42v where the cells all start to wander off unevenly, then 30 mins later they are all at 3.64 and never goes anywhere near 3.9v.
I also removed the bms to reduce any current loss in it both while sat and running. The bms also seemed to drag down 4 cells (I guess it needs 12v to operate) meaning I would have to unplug it every time I left it unused for a few weeks. This never made a huge difference but I believed it was helping bring the pack out of balance and prolong the agony of wanting my bike fully charged to ride while the ping charger slowly balanced the pack. I often notice say 1-4 cells at 3.30v and cells 4-8 at 3.48v although in ah terms it would prob be 0.2ah max. I guess this is why Ping supplies the bms unplugged now as it is in transit for weeks.
I now have a voltage alarm set to 3.0v which means I have around 2ah left maybe and to start pedalling harder when it beeps rather than suddenly have the bms cut out and have to push a hub motor 5 miles home lol. The bike seems to feel more lively right till the end now the current isnt passing through the bms circuits. Before removing it I noticed a slight drop in performance near the last quarter of the packs life. Maybe this is just psychological lol.
For me I have extra heavy duty charge sense wires fitted but to the average ping owner im sure you can use the bms sense wires combined with the two main charge leads to get your alarm working on every cell. The reason I have extra leads mainly was to use my cellpro10 charger to charge via its pig tail connectors only. No disconnecting of the packs main leads is now needed for this set up.
The cellpro10s is the Best £100 Iv spent so far to make my EV life smoother and can now charge a bunch of lithiums for other projects like lights etc . The imax 8 has 300mah bleed current and the ping bms is likely to bleed off even less only working by turning the charger on and off according to cells hitting high voltage then waiting to be slowly drained down. The cellpro charger boasts 1 amp equalising bleed drain and can confirm this is at least 5 times faster than the ping charger and imax 8 at balancing
http://s1239.photobucket.com/albums/ff506/bionicdan/
