The only time these guess-o-meters are correct is when they read zero. I’ve had three OEM electric cars. The implementation of the guess-o-meter in the 1998 Honda EVPlus was by far the best. It consisted of a bar graph with two horizontal bars indicating the distance to empty in different conditions. The horizontal scale of the graph was distance in miles. The green bar was the distance if driven most efficiently. The yellow bar was the distance under the current operating conditions. Driving fast up hill with the heater blasting on a cold day would push the yellow bar towards the left much faster than the green bar. Coming back down the hill, the yellow bar would catch up with the green bar. When the car was stopped, the yellow bar changed to some unknown average. A quick glance at this graph provided all the information required. If the range needed was less then what the yellow bar indicated, but less than what the green bar indicated, then all that was required was to operate a little more efficiently and the destination would be within reach. If the destination was farther than what the green bar indicated, a charging stop was going to be required before reaching the destination.
The best thing that can be said about the guess-o-meter in the 2011 Nissan Leaf is that it is inaccurate. It consists of a number indicating the distance remaining in miles. It is based on some unknown algorithm that seems to have no relation to reality. It also has a state of charge gauge with twelve segments indicating the charge remaining. Unfortunately, each segment does not represent the same amount of charge. Over time it is possible to get a feel for the amount of charge each segment represents, but figuring this out and applying the knowledge at each observation of the gauge was more work than appropriate for an instrument that is intended for use in a moving automobile. The guess-o-meter in the Chevy Bolt is a combination of the instrumentation of the Honda EVPlus and the Nissan Leaf. It consists of three numbers: at the top is a theoretical maximum distance analogous to the Honda’s green bar. In the middle is a number indicating the distance based on some unknown algorithm which seems to take into account operating history and current operating conditions. At the bottom is a theoretical minimum distance. I do not understand why this number is anything but zero. If the car is powered on while sitting in a parking lot, the battery will eventually fully discharge without driving a single mile. The Chevy bolt also has a state of charge gauge that seems to be consistent and much more accurate than the corresponding gauge in the Nissan Leaf. The Chevy Bolt also has a very nice feature referred to as trend bars. These give an indication of the current operating conditions. If the car is currently being operating in a manner that would exceed the middle number, a trend bar extends upward from the middle number towards the theoretical maximum number. The length of the trend bar indicates how efficiently the car is being operated. If the car is being operated in a manner that would result in a shorter range than indicated by the middle number, a trend bar extends downward toward the theoretical minimum number with the length of the bar indicating who inefficiently the car is being operated. By operating the car in a manner such that the trend bars never extend above or below the middle number, will result in the range indicated by the middle bar being achieved. The trend bars make the Chevy Bolts instrumentation as useful as the distance to empty meter of the Honda EVPlus. It just isn’t as simple and requires more effort. Instrumentation should not only be accurate, but simple. While the guess-o-meters that just present a number are simple, they are not accurate, making them useless. Ed > On Feb 3, 2021, at 3:10 PM, Matt Lacey via EV <[email protected]> wrote: > > Likely the milage of driving up and down the driveway is much worse than > actually driving somewhere. > > The calculated range is based on how much energy used in the previous several > miles. > > She just needs to go for a drive to correct the calculation > > Get BlueMail for Android > > On 4 Feb 2021, 03:55, at 03:55, Bill Dennis via EV <[email protected]> wrote: >> She leaves the car plugged in all the time, even after it's fully >> charged. >> She uses 110V charging. >> >> Bill >> >> -----Original Message----- >> From: EV [mailto:[email protected]] On Behalf Of Peri Hartman >> via EV >> Sent: Wednesday, February 3, 2021 12:32 PM >> To: Electric Vehicle Discussion List >> Cc: Peri Hartman >> Subject: Re: [EVDL] Pandemic Cell Fade >> >> What does the Volt charger do at full charge and the cable stays >> plugged >> in ? Does it periodically recharge as parasitic uses discharge the >> battery ? What is her charging pattern and what was it before the >> pandemic ? It could be that, after one year, constant recharging to >> 100% >> damaged the cells. What Just pure speculation. >> >> Peri >> >> << Annoyed by leaf blowers ? https://quietcleanseattle.org/ >> >> >> ------ Original Message ------ >> From: "Glenn Brooks via EV" <[email protected]> >> To: "Electric Vehicle Discussion List" <[email protected]> >> Cc: "Glenn Brooks" <[email protected]> >> Sent: 03-Feb-21 11:26:39 AM >> Subject: Re: [EVDL] Pandemic Cell Fade >> >>> One of the Battery cells going bad, maybe. >>> >>> Sent from my iPad >>> >>>> On Feb 3, 2021, at 11:14 AM, Bill Dennis via EV <[email protected]> >> wrote: >>>> >>>> Pre-pandemic, when my mother-in-law charged her 2017 Chevy Volt, it >> would >>>> have about 60 miles electric range. Throughout the pandemic, she's >> done >>>> nothing with the car except drive it to the top of the driveway and >> back >> to >>>> check the mail. When we were finally able to get to Georgia to >> visit >> her >>>> this week after fifteen months, I notice that a full charge shows >> only >> 40 >>>> miles range now. Anyone ever notice anything similar, or have any >> guess >>>> why? >>>> >>>> Thanks, >>>> >>>> Bill >>>> >>>> _______________________________________________ >>>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >>>> ARCHIVE: http://www.evdl.org/archive/ >>>> LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org >>> _______________________________________________ >>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >>> ARCHIVE: http://www.evdl.org/archive/ >>> LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> ARCHIVE: http://www.evdl.org/archive/ >> LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> ARCHIVE: http://www.evdl.org/archive/ >> LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20210204/72949d8c/attachment.html> > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > ARCHIVE: http://www.evdl.org/archive/ > LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/ LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
