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[kashography]

Hey there
I wanted to calculate the expectet range of my bike on my way to work (a lot of city and some 80km/h pieces).

I startet with 100%, drove 36km to work and have 85% battery left, 38wh/km on this trip.
So the easy math to get the approximate range of (36km*100)/15 = ~240km

when i do this math with the 38wh/km i get a way higher numer: 38wh/km * 36km = 1368Wh right? When i calculate for the full 13khw of the battery i would get (36km*13000Wh)/1368Wh = 342km

Is the showed Wh/km not what i mean it is, or do i may not have the full 13kwh of the battery to use? Thanks für your advice

[Erasmo]

Yup on the low and high side of the battery capacity there is a buffer zone you can't use, this is to protect the cells. What you read on the dashboard is usable capacity.

[KrazyEd]

   The information isn't updated continuously. As stated in first reply, you will also not have the entire 13KW.
You will have to make several trips as similar as possible to determine your actual power used.
Try to make the trips long enough to use a significant portion of battery. If charging at private location,
use some sort of watt meter to determine exact amount of energy used. Kill A Watt is popular and
somewhat inexpensive here in the United States.
   If using public station, it should provide the information. If possible try to use same station, just as
you would if you were trying to determine MPG of ICE vehicle. There may be slight differences in
efficiency at different chargers. All should be within a specific range but small difference multiplied over
many KW or miles may add up. I would imagine that your consumption is somewhere in the range
of double to triple what you believe it to be.

[Ndm]

When my bike came back from the battery upgrade the expected range was 80, it took a few rides to get it back to where it was and it's still climbing after nearly 3000km on the new battery, the estimator is fluid and constantly adjusted to the previous rides

[kashography]

When my bike came back from the battery upgrade the expected range was 80, it took a few rides to get it back to where it was and it's still climbing after nearly 3000km on the new battery, the estimator is fluid and constantly adjusted to the previous rides

But i am not talking about the expected range that my zero estimates. I am never looking at that. I look how far i got with how much percentage and that gives me a more accurate range.

@ KrazyEd & Erasmo
Thanks, i will do more tests and will report more. Because when i sum up the driven 1368Wh in 15%, that would be only about 9.5kwh for 100%, what is littly .
Yesterday i did 140km (87.5miles) with 64% of my battery, but i do not remember at the wh/km number. somewhere +- 40

[Doug S]

The "nominal" battery capacity is really a marketing number, it's not something you're ever going to achieve in real life. Check the Zero app, it shows you the actual battery capacity, and I guarantee you it isn't going to be very close to 13 kWh.

My 2014 SR is rated at 11.4 kWh but the app shows the real value to be ~9.2 kWh, and it hasn't changed much if at all since I've owned the bike.

[Ndm]

Sorry I misunderstood the first time, I have the 13kw battery now and the highest I see on the app is about 12.1kw at 100 percent, my average is 78wh per km so I used that as my calculator for any rides that would be close to my total range, I use 10 percent for errors and it gives me a close guess, I usually get about 150km mixed to a full charge,which falls within the calculation

[NEW2elec]

+1 for what Doug said basically you can go by what Zero talks about on their main web page and manual for factors leading to more or less range.  Speed, heavy or light throttle, hills, riding up or crouched, wind, temp, rider weight, regen setting all affect your range.  Go on routes when you have plenty of time and see what your average is.  Going fast hurts that avg. going easy helps but with your battery going 35-50 MPH will get you about 100 miles  mixed riding.  If you see any major drops see your dealer.
Fun bikes.

[DPsSRnSD]

I'm confused by the wh/mi I see on the bike. I'm getting about 60wh/mi riding on a 50 mph street with a lot of intersections with traffic lights. But the Zero app reports I'm getting about 90wh/mi, which I think is the right number. Has anyone else seen this?

[BertTrack]

I sometimes do that game when riding long distances on my FX.

I have 6.5kwhr in the battery tops. (aprox)

A 65whr/hr drain from lights. (aprox)

So if i then go riding and i keep my whr/km on or below a certain number i know i can get somewhere.

If i keep it on 50whr/km i should be able to do 130km. This would take me 3 hours (aprox) so i'm loosing another 190whr from the lights. So make it 125km. aprox with a charge.

I've done this in reality and that works out nicely. It's a bit long for a ride. And slow. And you need to keep your accelleration low to ... 50wh/km as well. But that way it does work.

At least for me.

[BrianTRice@gmail.com]

The momentary Wh/mi figure on the dash is inaccurate for some design reason I haven't gotten a good answer on or figured out myself; obviously, groundspeed and voltage are accurate but amps is probably the inaccurate/imprecise factor. The "trip" reading is averaged out and seems less inaccurate, but provides very slow feedback.

I do know that moment-to-moment variation in the dash reading partly corresponds with airspeed / winds, once you've removed other factors like groundspeed and angle of incline.

Definitely be aware that nominal battery capacity is not the maximum capacity. I've summarized others' explanations here:
http://zeromanual.com/index.php/Unofficial_Service_Manual#Capacity

What does seem to be accurate is the estimate of range remaining, but this can also be projected from the state of charge reading (on newer bikes), trip miles, and battery capacity. I try to think of 1% per mile as a baseline and determine how far above or below my current riding is in relation to it. On my 16DSR, 13kWh max is 11.4kWh nominal so roughly 110Wh/mi yields 100 miles range.

[kashography]

i just finished my dayriding with 105km and 49% battery left. The boardcompuer sayd 39wh/km, whats really not true at all, because the last 50km were fast and steep hills..

after my work, it was 10° warmer than in the morning when i wrote the post. so the battery showed 2% more battery when i "started" the bike never the less, i drove much faster and drew the battery much harder for the last 60km today. and when i calculate the math with the new numbers, 100% battery only would be 8.27 khw.

what i see:
1. Boardcomputer is wrong with the wh/km, as BrianTrice said. (by the way, zeromanual.com is nice, have to read more on there!)
2. I have to test and see what the app sais instead, i will post the difference here
3. 10° C higher temperature increased my range/batteryload a bit
4. Speed is the highest factor for battery usage (i knew that, but i see it clear now)

but i still always got ~180-240km upscaled for 100% battery usage on the last 5 days of driving at minimum 100km/60miles per day (no highway). So i am really happy

[BertTrack]

Riding 105km with 6.63kwhr (theoretical) would mean 63wh/km i believe. That would be your avarage usage.

[mrwilsn]

Just so were all on the same page about what we are looking at...

The average watt hours per mile that shows up on the app home page is averaged over every mile on the ODO.  In my case 118 wh/mi based on over 14K miles on my bike.



The Wh/mi that shows up on the display under the TRIP AV is the average just for that trip.  The TRIP AV will reset when the TRIP 1 resets.  If you start at 100% TRIP 1/TRIP AV will both be reset.  If you ride and then recharge but don't recharge all the way to 100% the TRIP 1/TRIP AV will not reset.  I have also noticed that if I ride but only get down to ~90% and then recharge to 100% the TRIP 1/TRIP AV will not reset.  I haven't been able to work out the exact criteria for what triggers a reset.



Notice that TRIP AV is 61.7 Wh/mi but the average shown on the Zero app home page show 118 Wh/mi.  That's the difference between average consumption over just the 105.7 mile trip I took vs. the average consumption for the 14K miles on my bike (only 11473 ODO at the time of the 105.7 mi trip).

( 105.7 mi / 77% ) * 100% = ~137 mi (Note that the city range stated by Zero for a 2014 Zero S ZF11.4 is 137 mi...spot on)

137 mi * 61.7 Wh/mi = 8452.9 (8.452 kWh)

But if you look in the app my bike shows a capacity of 10.672 kWh.

10672 Wh / 61.7 Wh/mi = ~173 mi

10672 Wh / 137 mi = 77.9 Wh/mi



So now that we are all looking at the same information...the question is...does the bike have 10672 Wh and my trip really used 77.9 Wh/mi or does the bike have 8452 Wh and my trip really used 61.7 Wh/mi?

Note that the app also reports 92 Ah capacity.

92 Ah * 116 V = 10672 Wh

2013 and 2014 Zero's use Farasis 25 Ah bricks (2015 use 27 Ah, 2016 use 29 Ah).  2014 Zero S ZF11.4 has 4 bricks (2015 ZF12.5 and 2016 ZF13 also use 4 bricks).

(25 Ah * 4) * 116V = 11600 Wh

The Zero website lists the max capacity as 11.4 kWh and nominal capacity as 10 kWh.

Hmmm...more....data....required....

OK...time for another trip.   This time notice that the app shows my capacity is 10.764 kWh before I start my trip.  But still 92 Ah.  We see that the reason for this is that looking at the Battery 2 page shows the voltage is 117 V.  117 V * 92 Ah = 10.764 kWh.  Also note that the cell balance is just 1 mV !!!!  Holy smokes...that's REALLY good.  It's actually bouncing between 1 mV, 2 mV and 3 mV but I timed the screen shot to show that it was getting down to 1 mV.





At the end of this trip I had only gone 67.1 mi with only 18% battery left and 104.2 wh/mi.  Running through all the calculations again...

(67.1 mi / 82% ) * 100% = ~82 mi (Note that the highway range stated by Zero for a 2014 Zero S ZF11.4 is 70 mi @ 70 mph and I was going 60-70 mph for the majority of the trip)

82 mi * 104.2 Wh/mi = 8526 wh (8.526 kWh)



OK...one last data point.

This time I take the same route as trip 2 but there is traffic and I am able to do some serious drafting.  I go 88.6 mi with 11% battery left.  I averaged only 85.9 wh/mi even though I was still going about 70 mph for the majority of the trip (thanks minivans!!).

Doing the math one last time...

(88.6 mi / 89% ) * 100% = ~99.5 mi

99.5 mi * 85.9 Wh/mi = 8551 wh (8.551 kWh)



Also, looking again at the battery 2 page the cell balance is still 3 mV with the battery voltage at only 88 V....WOW!!!  That's amazing....it's not uncommon to see a cell balance of 50 mV - 150 mV at low SOC so 3 mV is amazing.  Way to match those cells Zero!!



So to recap...3 trips...

105.7 mi, 77%, 61.7 Wh/mi = 8452.9 Wh (8.452 kWh)

67.1 mi, 82%, 104.2 Wh/mi = 8526 Wh (8.526 kWh)

88.6 mi, 89%, 85.9 Wh/mi = 8551 Wh (8.551 kWh)

Those numbers seem pretty consistent.  My educated guess is that SOC is based strictly on battery voltage, Ah is just a spec number calculated based on battery voltage, the capacities in the app are based on specs and battery voltage and the Wh/mi provided by TRIP AV is based on real time measurements.  This would then imply that the Zero app numbers of 10.672 kWh to 10.764 kWh and the Zero specs 10 kWh nominal, 11.4 kWh max are just simple calculations based on specs and industry standards that don't mean much.

To cross check the numbers you can get a Kill-A-Watt meter to measure how much energy is going back into the bike after the ride then divide by the miles ridden (I don't have a Kill-A-Watt meter...yet...so I haven't done this myself...but I bet @Electric Terry has).  No different than calculating miles per gallon by measuring the number of gallons of gas you put into your car after a trip and then dividing by the number of miles for that trip.

But you may be left wondering....wait...Zero says the bike has anywhere between 10 kWh and 11.4 kWh but it really only has ~8.5 kWh...that's BS!!  Well...maybe...but considering the range numbers fall right in line with the Zero specs...who cares....battery capacity isn't really what's important....it's just a means to get more range...better aerodynamics and slower speeds are also ways to get more range.  As far as I'm concerned...as long as my real world range is close to the Zero specs I don't care about the real capacity of the battery....actually that's not entirely true....when I want to calculate my target Wh/mi for the distance I need to travel I use 8.5 kWh in my calculations.

[kashography]

Hey mrwilsn

nice report, thanks.
Even the boardcomputer or the app is not correct. I have about 1000km now, and the boardcomputer is mostly arround 40wh/km. My app says, that i have a 60wh/km over the whole 1000km. so there is about 1/3 difference

On my app;
100% charged is 12.064 kWh (on a 13kWh Battery, so about 1kWh buffer?), 116V and 104 Ah.
with 54% its 5.916kWh, 102V and 58 Ah.

So i think the App is right with its about 60wh/km, and the boardcomputer is wrong?! Im going to get a Watt-Meter sometime and then we know it for sure^^