What battery to buy for a Voilamart 500w 36v front hub?

[rayhigh]

Hi all, new to the forum and this is my first post so be gentle please!

I'm just about to get hold of a Voilamart 500w 36v front hub (new second hand, 3months old never been out of the box).

I'm looking for a battery and found one that's 36v 13ah for £220 (inc rear rack).

Is this going to be a wise choice?

I understand the Voilamart kit is popular so can owners give their experience of what batteries they have and what performance they get from them?

Regards... Ray

 

[Nealh]

The reason for their popularity is the cheapness but that means the electronics are crappy giving not much control over power delivery and user friendliness.

 

[Benjahmin]

Lot's of posts here about this kit. The motor is direct drive so not good at stop/start and hill climbing. It's happiest on flat high speed runs.
At low revs it will be inefficient using lots of battery power to turn to heat. They seem to use a high current controller so need a high maximum current battery to avoid voltage sag and cell damage. Whatever the maximum current of the controller is the battery should ideally be capable of delivering 1.5 times this amount. This will make the battery expensive.
Note the above is not the capacity (Ah or Wh rating) but the maximum current capacity - not always quoted in sale blurb.

 

[ldc]

Lot's of posts here about this kit. The motor is direct drive so not good at stop/start and hill climbing. It's happiest on flat high speed runs.
At low revs it will be inefficient using lots of battery power to turn to heat. They seem to use a high current controller so need a high maximum current battery to avoid voltage sag and cell damage. Whatever the maximum current of the controller is the battery should ideally be capable of delivering 1.5 times this amount. This will make the battery expensive.
Note the above is not the capacity (Ah or Wh rating) but the maximum current capacity - not always quoted in sale blurb.

what do you mean by direct drive? what motors to you recommend

 

[Nealh]

D/D or direct drive means the heavy hub is gearless inside and has no clutch mechanism to allow it to freewheel with no power so it turns them in to a nightmare should the battery cut out or something else goes wrong. Unlike a lighter geared hub which has internal gearing and a clutch that allows freewheeling with no power should an issue occur you can simply if need be cycle home or somewhere in a low gear though hills might be a drag, if the controller goes you can simply disconnect it to pedal.

 

[Benjahmin]

As Neal says, no clutch. So, when unpowered, the motor acts as a generator and you get the magnetic drag added to the larger weight of the motor.
It's this type of motor that has been used in bikes with regenerative braking, but the charge gain is so small ( due to the low mass of bike and rider) it has never proved worthwhile.