Anyone Tracking Charge Statistics?

Discussion in 'Clarity' started by MrFixit, Apr 22, 2021.

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  1. MrFixit

    MrFixit Well-Known Member

    There are a lot of different ways to 'manage' charging with a vehicle like the Clarity. After an ownership period of 2.5 years (~22K miles, 75% EV), I have executed a total of 430 charge cycles. Here are the resulting statistics...

    As a strategy, I tend toward 'full' charges. On trips longer than the EV range, I intentionally try to return home as I reach 0 EV miles. With multiple short trips around home, I tend to charge only after the EV range gets "low" (or if I'm about to go on a longer trip).

    The charges that were greater than 14 kWh all occurred within the first year. Any more, none of my charges exceed ~13.5 kWh due to the known effects of battery capacity degradation.


    Is anyone else 'geeky' enough to maintain this kind of statistical data?
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  3. JFon101231

    JFon101231 Active Member

    No, but coming from a CPA/excel nerd, I like it :)
  4. DrDeke

    DrDeke New Member

    Here are my per-day stats since I got my L2 charger installed (very shortly after I bought the car) :


    Chargepoint does have some CSV-exportable stats, but they are still on a kWh/day basis, not per charge or per minute.
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  5. MrFixit

    MrFixit Well-Known Member

    I love data !!!

    Does this represent virtually all of your electrical usage (you mentioned L2 installed shortly after you bought the car)?
    If so, your 1.25 MWh would correspond to something like 4K miles (using the EPA's 31 kWh per 100 mi.)

    If I ignore the peaks that are clearly the sum of multiple charges, there are still some peaks at ~15 kWh. Maybe even those could be a multiple charge because I think they are still a little over the battery capacity too. Then, there are quite a number of others that are in the 13-14 kWh range. Those seem like they may be single charges with an 'empty' battery, and are consistent with my experience.

    Thanks for posting your data...

    If you are technically inclined, you may be interested in monitoring your Battery Capacity over time. Honda's HV battery warranty is based on this figure. You can learn how to query this value yourself here:

    We have a shared spreadsheet where forum members have been accumulating a fair amount of data about battery degradation over time.
  6. DrDeke

    DrDeke New Member

    Yeah, this represents almost all (I'd say at least 95%) of my electric usage for the car. I occasionally charge elsewhere (relative's house, public charger), but quite rarely.

    I do have one of those Vgate OBD-II adapters; I'll take a look at the battery capacity PID soon and add it to the spreadsheet.
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  8. Denrac

    Denrac New Member

    It's almost a year old tread, but here are some charge statistics that might be of interest.
    I've monitored around 2500 "charge events" (labeled "événements" in the graphs) on my home L2 charger between june 2019 and march 2022. These account for over 95% of all charge events performed in that period of time on my 2018 (canadian) Clarity. I'm retired, so the car spend most of the time at home (particularly in this COVID era). In cold weather, i.e. from november through april here around Quebec City, the car is kept plugged as recommended by Honda. In warmer time, the car is charged as SOC drops below 70%. My L2 charger is limited to 30 amps.

    Since new, I've driven 28000 mi. with a day average of 20 mi.. There has been many multi-hundred miles trips, including vacations towing a small euro trailer-tent. The total average MPG (US) is 78 and MPGE is 140 (or 4.1 mi/kWh). The estimated ratio of EV vs HV miles is 55:45 since new (and 70:30 for the last couple years).

    From my data, I can recognize 3 types of "charge" event : battery charging ("recharge de la batterie" in the graph), battery heating ("réchauffage de la batterie") and what I've called battery monitoring ("surveillance de la batterie"). Each type has a specific profil related to energy consumed (kWh), peak amperage (max amperage) and elapsed time ("durée") (Some highest time elapsed values could be ignored as the home power controler pause EV charging when kitchen appliances require power)

    For each event type, 3 smaller graphs display the number of events vs each characteristic with a table showing averaged value ("moyenne"), standard deviation ("écart-type"), minimum and maximum values. A fourth graph shows the time distribution of consumed energy.
    The battery monitoring event type might be related to battery heating as showed by the time distribution of those events (kind of checking if the battery needs to be warmed). Battery heating require around 200 kWh per season.

    Battery capacity readout was 49.3 Ah in january 2022 (from 49.9 nine months earlier).

    Stat_1.jpg Stat_2.jpg Stat_3.jpg test
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  9. Steven B

    Steven B Active Member

    @Denrac, I am curious about this statement:
    "Some highest time elapsed values could be ignored as the home power controler pause EV charging when kitchen appliances require power"

    What device or devices are providing you with this functionality? I think this would be good information for homeowners putting in an L2 EVSE when the breaker panel is old and undersized or even when they use the L1 charger in a garage on a shared circuit with a freezer, etc.
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  10. Denrac

    Denrac New Member

    @ Steven B : the power controler used is a device I've builted around a Raspberry Pi-zero micro-computer (a computer half the size of a credit card) and a Siemens VersiCharge L2 EVSE. The VersiCharge is, to my knowledge, the only EVSE having a wired remote control interface.

    The VersiCharge control interface consists of 2 dipoles : a "control switch input" that, when shorted (by a dry contact), puts the EVSE in lock mode and stops charging. The second dipole called "status output" is shorted by the EVSE when charging.

    Other hardware are a pair of clipped on wire SCT-013-000 current sensors, an Arduino ADS1015 analog to digital converter, a HL-52S electromechanical relay module, some resitors and LEDs for the visual interface, a wall wart power supply and the 60 amps electrical sub panel with breakers for the kitchen oven, the induction cooktop and the EVSE.

    I've writen the control code in Python 3 which comes with the Rasbian (Linux) operating system distribution, after installing GPIOZero and Adafruit libraries. Python is an interpreted programing language with a high overhead, so current readings are not as fast as the hardware permits.

    The control code has 3 main functions :

    -- First, every second it reads the current entering the sub panel and the current outpouring to the EVSE. It stops or prevent from starting the EVSE (via it's "control switch input") when the incoming current reaches or might reach the continuous duty limit of the panel (48 amps for a 60 amps panel). When the EVSE is not in use (sensed via the charger's "status output"), it assumes it could start at any moment at full power (30 amps). The LED inferface always displays one of the 3 states : charger ready, charger in use and charger locked. The "control switch input" is wired to the normaly-closed side of the electromechanical relay, so that if the program is halted for any reason, the charger remains locked (and the kitchen appliances can have all the power).

    -- Second, once a day, during a charge event, it momentarily stops and then restarts the charger to check the wired control response. If it's not functioning as required, the LED interface displays an alarm signal.

    -- Third, during a charge event, it computes the total energy going into the EVSE via the current sensor on the EVSE wire and writes it in a log file together with the maximum (1 second) current and the elapsed time of the event. The log is periodically dowloaded to an EXCEL spreadsheet.

    A similar system could be built around a smart EVSE using WiFi or Bluetooth connexion, but the fail-safe mechanisms might be trickier to implement.

    Although I've worked as an information technologies analyst, computer hardware and programing is not my domain of competence nor am I an electrical engineer, but building that controler was a fun DIY project. I could provide more detailed information if requested.
  11. Steven B

    Steven B Active Member

    There is a coming market for this if it can be simplified and commercialized for the "matter" smart home standard.
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