Steve,Is your worst case really 230 Wh / mile? That's rather incredible (translates to 4.3 miles / kWh). That's around the *best* I ever get with my Leaf, in summer. What are you driving, and where?
Peri
------ Original Message ------ From: "Steve Heath" <[email protected]>To: "Peri Hartman" <[email protected]>; "Electric Vehicle Discussion List" <[email protected]>
Cc: Sent: 06-Dec-18 9:28:14 AM Subject: Re: [EVDL] poor 2011 Leaf performance
It could well be. The charts you refer to have so many caveats that the figures are only a very rough guide. This is one of the major problem of calculating range.The best mile/Kw I have got has been 180 and the worst is 230. Average is 190 and this measurement is based on coulomb counting over the distance. i.e. measuring the amount of power supplied by the batteries to travel the distance. This is not the same as the amount of power from the plug to charge the batteries nor is it the same power that the motor uses which causes further complications. The distances btw are also near the theoretical maximum that my battery pack can support so that the effect of the battery capacity curve cancels out.If I use the capacity used based on voltage then it can get very silly. I was getting figures of 600-700 w/mile because the voltage vs soc is non linear. I could drive 25% of the range and the capacity would drop to 50%. This did not make sense so I stopped using them and fitted coulomb counters. I do use the voltage to predict low battery but the rest of the data is just a rough guide. The gauge does look pretty on the dash though.Get the Leafspy and start collecting your own data and use that to build up the values for your car. That will indicate exactly what is happening.Cheers Steve On 06/12/2018 16:24, Peri Hartman via EV wrote:So, Steve, are you inferring the the 3.2 miles / kWh number could be inaccurate? If it's reasonably accurate, it becomes irrelevant on how efficiently I'm driving (yes, stop & go makes a big difference).I agree, my capacity and remaining charge estimates may be off. That's where the LeafSpy would help. Again, anyone care to recommend a ODB2 device?Peri ------ Original Message ------ From: "Steve Heath" <[email protected]>To: "Electric Vehicle Discussion List" <[email protected]>; "Peri Hartman" <[email protected]>Cc: "Haudy Kazemi" <[email protected]> Sent: 06-Dec-18 8:00:26 AM Subject: Re: [EVDL] poor 2011 Leaf performanceThere is another factor: 14 miles in one hour indicates to me a lot of stop start running and this can have a serious effect on the efficiency of the car.I do notice that stop start driving is not as efficient as cruising and there is little or no regen on braking. End result is a 15% difference is consumption in my experience.I can use less energy taking a longer route that has no speed bumps compared to one with them where I have to slow down and accelerate from.Although my car is a conversion, I do have very good coulomb counting instrumentation of what goes out and into the batteries and on the chargers and these agree within 1%. I also have a voltage system that monitors the voltage and controls engaging Turbo mode if that will force the battery voltage to drop below the BMS panic level. What is interesting is that the coulomb counting is pretty well consistent but the voltage representation can vary as much as 20%. LiION batteries are very difficult to measure SOC from the voltage except for the two extremes.So what happens is that the coulomb count is ok but the capacity estimate from the voltage can and does vary.So add all these factors up and it can explain where the missing power has gone.I would also expect to use more than 1 kw for heating. Definitely worth getting more accurate data. On 06/12/2018 15:23, Haudy Kazemi via EV wrote:Leaf owners can benefit greatly from the LeafSpy app (not free) and a quality bluetooth OBD2 adapter. They can then look at the detailed healthand capacity stats in app. My guess is 9 bars would be about 16 kWh capacity. You may also be losing energy to sticky brakes. Some brake exercise,including using the parking/emergency brake may be in order. Brake issues are a common issue on gently driven vehicles with regen because the brakesdon't get warmed/worked out much.On Wed, Dec 5, 2018, 13:11 Peri Hartman via EV <[email protected]> wrote:Thanks, Collin. That affirms one part of the "mystery": poor range in winter. The other half - missing 3.5 kWh - still persists. Peri ------ Original Message ------ From: "Collin Kidder" <[email protected]> To: [email protected]; "Electric Vehicle Discussion List" <[email protected]> Cc: Sent: 05-Dec-18 9:13:32 AM Subject: Re: [EVDL] poor 2011 Leaf performanceI have two leafs here - 2012 and 2013. The 2012 is lucky to get 40miles of range in the winter. In the summer it's closer to 50 miles.The 2013 can drive somewhere in the range of about 40-45 miles inWinter and 60-70 miles in Summer. I wouldn't consider any of that tobe great but that's how it is. As far as I've heard, the batteriesthey used in 2011 and 2012 were pretty bad and degrade very badly overtime. By 2013 the batteries got better then more recently they got better again.I think there is an issue where the cells do very poorly in Winter and you don't get nearly the range you would calculate you should be able to get. Be very careful how far you drive in Winter with these things. I basically drive back and forth to work and charge when I get to work (there's a J1772 6kw charger here). I don't usually have to charge at home, even in Winter, even if I drive around a bit between home and work. But, I live 9 miles away from work so that's only 18 required miles to get back and forth. Still, driving 9 miles from work to homein Winter will easily take 20% charge, sometimes more. This agrees with my above guess. 9*5 would be 45 miles range at best.On Wed, Dec 5, 2018 at 11:27 AM Peri Hartman via EV <[email protected]>wrote:Cor,So, just to make sure I understand, you have 8 capacity bars, whichyou're assuming is 100% - 15% - 3 * 6.25% = 66% of 24 kWh, or about 16 kWh, correct? In my case, with between 8 and 9 capacity bars, that would be 100% - 15% - 2.5 * 6.25% = 69%, or 24 kwh * 69% = 16.5 kWh.My estimate for the range remaining doesn't change - I used the tableinthe link below and did not assume them to be linear. So the rest of mycalculations are unchanged. Still results in 3.5 kWh being "lost" somewhere.If someone local (Seattle) has a gid meter and is willing to lend it,Imight be able to get some more accurate extrapolations. At least I'dknow the true capacity and the true amount of energy used, right? Peri ------ Original Message ------ From: "Cor van de Water via EV" <[email protected]> To: "Electric Vehicle Discussion List" <[email protected]> Cc: "Cor van de Water" <[email protected]> Sent: 04-Dec-18 6:48:24 PM Subject: Re: [EVDL] poor 2011 Leaf performanceCapacity bars are not linear.The 12 bar display is actually anything from 85% to 100% capacity. Below that, every bar stands for 6.25% if I am not mistaken (quoting>from memory)So 7 bar capacity can be as low as 100 – 15 – 4 x 6.25% = 60% so lessthan 15kWh. Also, there is a reason it is called the GOM (Guess-O-Meter).My Leaf has 8 capacity bars. I can drive home and go from 12 quicklyto10 or 9 and then arrive home with only 6 or 7 bars left.Then drive to work starting with that half charge and arrive at workwith still 3 bars left….I have noticed that range bars are not linear, so you can’t say Xbarsis so many kWh left.GIDs are a better measurement, so use LeafSpy and you can much betterjudge what your Leaf is doing. Hope this helps, Cor. Sent from Mail for Windows 10 From: Peri Hartman via EV Sent: Tuesday, December 4, 2018 6:13 PM To: Electric Vehicle Discussion List Cc: Peri Hartman Subject: [EVDL] poor 2011 Leaf performanceAnyone want to take a stab at this mystery - poor performance of my2011 Leaf ? Temp about 45F Heat on: drawing average of about 1 kW "other systems" drawing about .25 kWDrove 14 miles, went from 12 range bars to 5 bars (full charge levelis9 capacity bars) Average 3.2 miles / kWh Duration about 1 hr.Driving pretty carefully - usually only 2 "balls" on the usage meter.For electrical systems, I estimate I used about 1.25 kWh. For traction, 14 / 3.2 = about 4.5 kWh Total: 5.75 kWh. According to https://electrolease.nz/blog/nissan-leaf-range-charts-and-tables.html 5 bars equates to about 45% charge remaining.Assuming that the capacity bars are linear and I'm between 8 and 9,thebattery should have somewhere near 17 kWh (24 originally). 45% of that is about 7.5 kWh remaining charge.Add in what I've used, 5.75, makes 13.25 kW - but should be around17.Plus extrapolating the mileage: 14 / 45% = 31 miles estimated totalrange. What happened to the other 4 kWh?And, am I the only one who get 31 miles per charge? This Leaf has had miserable winter range since the beginning. Still don't know why.Peri -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20181205/ac242f27/attachment.html_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20181204/67c9fb0f/attachment.html_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA ( http://groups.yahoo.com/group/NEDRA)-------------- next part -------------- An HTML attachment was scrubbed...URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20181206/500b6fe9/attachment.html>_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.orgPlease discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.orgPlease discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
_______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
