Battery power dependent on level of charge?

[Gionnirocket]

Perhaps if it could be implemented only when the voltage has fallen continuously below 48v... but then again adding even more complexity.
For me smaller lighter battery technology would be worth more. Then you could go 8+ in parallel

 

[harryS]

Using a converter will cost you in efficiency. I tested a boost converter to raise my 36V battery to a constant 48V. Lost 15% range, going at the same speed. Where's the power lost? Conversion. You could get better efficiency with better magnetics.

The converter was about $25, and it worked surprisingly well for a inexpensive piece of gear.

Bicycles are simple enough that it's enough for the rider to simply pedal harder or just go slower, as the battery voltage runs down.

 

[PCeBiker]

,.. I tested a boost converter to raise my 36V battery to a constant 48V. Lost 15% range, going at the same speed.

And,.. That 15% loss of range is all turned into heat almost entirely in the converter, so 15% of your battery's ah rating would be how much energy the converter has to dissipate as heat.

Another thing that bothers about the idea, is that as the battery's voltage drops, it has to put out more and more amps into the converter, for the converter to have the same output.

Right when you should start going easy on a tired battery, is when you ask the most of it.

 

[6zfshdb]

And,.. That 15% loss of range is all turned into heat almost entirely in the converter, so 15% of your battery's ah rating would be how much energy the converter has to dissipate as heat.

Another thing that bothers about the idea, is that as the battery's voltage drops, it has to put out more and more amps into the converter, for the converter to have the same output.

Right when you should start going easy on a tired battery, is when you ask the most of it.

Yes, heat is the main reason for the loss, however a booster is less efficient than a buck voltage reducer. They don't generate as much heat.