it just seems like the risk of having to handle, unplug, replug, and unplug, and replug the balance harnesses into the parallel series harnesses all the time would lead to the leads breaking off on a regular basis.
plus this is charging at .1C with this little charger but if you had a regular bulk charger you could be charging at 1-2C with less cost for the charger and if you got one of these BMSs from bestekpower that agnius found then you would have protection for the battery from accidentally shorting the output or from accidentally leaving the pack connected to the load and over discharging.
the lipo stay so well balanced they don't need the long time balancing like the lifepo4 and if you had a BMS on the pack then you could put a switch in the circuit current to turn off the pack when you are handling it, or plugging it into the controller so you would not have the spark problem when connecting to the controller.
i wish there was someone who could do the data com hack on this one and do a thread on it showing how the LCD display could be used to monitor the health of the battery. it has a self discharge rate monitor which seems like it would be an ideal indicator of battery problems and it has a thermal breaker to stop charging when the pack overheats and it also has a thermistor to monitor pack temperature during use. i think you can order it with the 15S and maybe even add some shunt resistors to increase the current capacity and then hack the output mosfets with something larger but it would be 15S lipo so the 62V would work with the regular 36-48V controllers and you could charge with a regular 48V lifepo4 charger adjust up a little to the 62V: http://www.bestekpower.com/fuelgasgauge/BMS-D141.html
or this one for 24S lipo which is rated 80A which seems conservative: http://www.bestekpower.com/888v24spcmbmspcbforli-ionli-polymerbatterypack/PCM-D131.html
sacko just bot one delivered for $73 so i thought it was a deal too. che.aper than the signalab from ping or the same from BMS battery