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[deckofficer]

Staying within the design parameters of the components used, my guess is based on the 29 Ahr cells being capable of 5C discharge like the old 20 Ahr cells.

Controller at 102 volts and 775 amps would be good for 106 hp. After being schooled by Doctorbass I learned that 550 amps is the input rating and after subtracting efficiency turns out 70 hp is about it, nothing left on the table.

Battery at 13 kwhr and 5C discharge would be good for 87 hp.

Battery at 16.3 kwhr would be 109 hp, controller could handle this small % increase.

Since output is limited to 70 hp, Zero is being very conservative, leaving 39 hp on the table.

[Doctorbass]

Here is an interesting question that also has been adressed few times in the past

The Zero size 6 controllers are not in fact 775A but 550A.  the 775A is the phase current and 550A witch is their rating on the label is the battery current.

See page 3-9 on this document: http://www.thunderstruck-ev.com/Manuals/Gen4_Product_Manual_V3.0.pdf

Then let say you consider the battery voltage sag under load with the most powerfull actual setup availlable, the ZF13 with powertank = 29Ah x 5 = 145Ah
145Ah x 5C = 725A continuous and 10C burst ( if i remember correctly) = 1450A burst... but still limited by the  battery 300A internal class T fuse or the 500A controller fuse and the delay that leave some margin for higher amp .. The sag is aproximatively 4V under full power so at 116V full charge you get 112V at 550A.
This give 61kW

Btw the real battery capacity you should use  is by using te Ah x nominal voltage ( not maximum voltage as Zero ZF advertize as "maximum capacity") this give you 145Ah x 102V = 14.790kWh energy.

The actual rating is 52kW, however i ever saw up to 59kW on the Zero apps ( not sure how precise is that data collection but i suppose it come from the current sensor of the controller witch should be pretty precise.

So.. at the battery side you could consider 59kW as the maximum someone saw and 61kW as the maximum possible power draw by the controller.

Some legend say that few ever tested dual size 4 with splitted  motor winding. these are 350A rated so 700A burst.

I've been told that the actual 75-7R IPM can output about 100hp...witch is the maximum before saturation occur.  It could be probably with dual size 6...

But we know that Arlin succeded to build a E motorcycle outputing 81hp on his DIY dyno... this was with 75-7R and dual size 4 setup.

This give you some perspective

Doc

[deckofficer]

Thanks Doc, very informative. On one of my old projects I was using the Winston LiFePO4 100 amp cells when they started to come down in price (about 10~12 years ago). Prior to this I always used Odyssey AGM lead bricks. You mention that Zero's pack sag is 4 volts under 550 amp load, which at 116 pack voltage isn't bad. With the AGMs I saw almost that much at the 12 volt single battery level. At 96 volts if memory serves me, about a 25 volt sag. We have come a long way in 10 years. My Winston cells gave me my first experience of very low sag under high current. I still have those cells and they are still performing fine.