Batteries in Series

[Recumbum]

The GM 24v 16ah batteries - if a person took two of them in series to give 48 volts, you would have almost double the number of ah's and I would think it would be a bigger bang for the buck than the 48v 20ah battery. Yes?

[Bikemad]

The GM 24v 16ah batteries - if a person took two of them in series to give 48 volts, you would have almost double the number of ah's and I would think it would be a bigger bang for the buck than the 48v 20ah battery. Yes?

Unfortunately it's not that simple, you would have double the voltage, but the same 16Ah rating.

If you put them in parallel, you would have a 32Ah rating, but it would still be a 24Volt battery.

Alan
 

[Recumbum]

The GM 24v 16ah batteries - if a person took two of them in series to give 48 volts, you would have almost double the number of ah's and I would think it would be a bigger bang for the buck than the 48v 20ah battery. Yes?

Unfortunately it's not that simple, you would have double the voltage, but the same 16Ah rating.

If you put them in parallel, you would have a 32Ah rating, but it would still be a 24Volt battery.

Alan
 

Oh sure, ya had to rain on my parade huh! grin Well so much for that idea.

[Leslie]

There is logic in adding AH in series.  Alan response was correct 2*24 16AH in series it still a 16ah battery.

1.  The hub will consume more current at higher volatges
2. Say your packs last for an hour and 15mins normally, you may will go an hour and 5 mins at 48v but at 45 kph.  Not quite double distance but faster and further.
3. The pie should be fine and efficient at 48v unless there are huge differences between the voltage models.

Unless the motors are wound with a notable difference you may get up to 90% more distance at double voltage.  That being from 24v to 48v.  Higher series pack voltages, the hub will suffer from larger inefficiencies then some wish to accept.

Its possible your model Pie will be perfect at 48v and maybe a sunny parade after all.  Just check your windings and their impedances and compare them to a 48v model before you leap.