"What is my actual battery capacity/range?"

This is, hopefully, first in a series of informative posts about Zero motorcycles and batteries. The goal here is not to disparage Zero, but to inform people about the differences between marketing numbers, the real world, and how to anticipate what they can actually do.

Zero batteries can be thought of as a series of 'small bricks'. Like Tetris, 4 of them form a square. The FX platform either uses 2 individual small bricks or two tied together into one 'long brick'. The S/DS platform uses a Tetris square battery case that either houses 1 or 2 'long bricks' in what they call the 'monolith'.

As of right now (4/13/19) each 'small brick' is listed as a 3.6kW unit. Therefore a 'long brick' is 7.2kW, and the largest monolith is 14.4kW.

These are, for lack of a better term, marketing numbers. They would lead you believe that if you were to drive the bike at, let's say 120 Watt hours per mile, you would have a 120 mile range on a full charge.

Let's delve a little deeper. BUT NOT TOO MUCH. DO NOT BE SCARED.

Watts are a unit of measurement that is literally Volts multiplies by Amps. All Zero batteries on all Zero bikes operate between 95-116.4 Volts. Consider that the empty and full measurements on a gas tank gauge. This means the midpoint in there is actually ~102 Volts. Remember that.

The Amp Hours of the pack are the next key factor. Farasis, who manufacture all of Zero's batteries, stamp on a nominal Amp Hour battery number onto each pack. Again, this is sort of a marketing number. There is no way for the default, average user to see this data unless you watch the CAN signals of the bike. As I have ways of watching the CAN signals I happen to know what various values of the batteries actually are in actual amp hours instead of nominal/marketing.

For example, I have a 2016 SR with a 13kW monolith and a 2.8KW Power Tank. One would therefore assume I have 15.8kW of battery at my disposal. Not quite. Marketing numbers.

A closer investigation reveals that the 13kW monolith is actually 104 Amp Hours, meaning it's made up of 4 of the 26 amp hour small bricks. Well, shit, 104x116.4 (max voltage) doesn't sound so bad, right? That's 12105.6 or 12.1kW of battery instead of the marketing number, right? Well, not quite. You need to measure the mid point because half the time the battery above that and half the time it's below that. That's 102 Volts. That means 104 Amp Hours x 102 Volts (104*102)= 10608 or 10.6kW.

This means my 13kWh monolith has a real world value of 10.6kWh. Additionally, my 2.8kWh Power Tank lists as 25Ah from Farasis, but the bike recognizes it as 22Ah. Combining my 104Ah monolith + my 22Ah Power Tank yields a 126Ah battery system. Multiply that by the median voltage (102), and you'll see I have a 12852 or ~12.8kWh battery.

Now that I know what I actually have I can measure my real world driving ranges based off it. Let's say in Eco mode at 70mph I set it to watch the Wh/mile setting and it's a value of 140. This is saying I'm using 140 Watt hours every mile. Well, let's take our 12.8kWh and divide out 140 it gives me 91.8. This is the range I can expect if I average 140 Watt hours/mile.

Remember that the SR/F has the same battery as the current top SR/DSR models and that 14.4 is a marketing number. As I don't have one I don't know the exact amp hours of the pack, but I assume it's ~120. This means an actual usable 12.2kWh battery pack.

Questions?