you can charge up to 50 watts or 5 amps, to do this you need to put about the same amount of amps into the charger.
to charge li-ions all you need to know is charge in li-po mode if its a 3.7 volt cell like an 18650 and positive goes to positive, negitive goes to negitive and for the best life of your li-ions dont charge any higher then 0.5 amps or 500 milliamps.
for series charging the amp,s of the charge always stays the same only the voltage goes up, the charger will sort the volts out its self.
for parrallel charging the amps double every time you add another battery and the voltage always stays the same, the charger will sort the voltage out but you need to increase the amps.
an example
series charging 6 x 18650,s is 22.2 volt at 0.5 amps will charge in the same time 1 x 18650 will charge at 0.5 amps.
parralell charging 6 x 18650,s is 4.2 volt at 3 amp and will charge in about the same time as 1 x 18650 but they all have to match in voltage and so on before connecting them up and this method is not recomended by me.
series in my opinion is better, but you need to balance charge.
B6 chargers do not like charging car batteries from my experince and they are in accurate for charging nicad,s and nimh AA,s AAA,s and D cell,s, but there are okish for li-ions and lipo,s with an accuracy around 0.04 to 0.4 volt per cell.