EV vs Hybrid Dashboard Indicator and can I force battery use

Discussion in 'Prime Technical Discussion' started by harhar, Oct 11, 2019.

  1. harhar

    harhar New Member

    Joined:
    Oct 11, 2019
    6
    1
    0
    Location:
    Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Prime Premium
    On the dashboard indicator there is the green bar (EV charge) and the blue bar beneath it. Our daily trip into town runs out of EV about 5km from home and it switches to ICE. Due to hills/highway I've been unable to stretch the EV any further trying all of the hypermiling methods I've read about.
    I am wondering about the blue bar once the EV battery runs out. This is the hybrid battery isn't it? Is there a way to force using the hybrid once I'm out of EV rather than turning the ICE on first? I'm already in ECO mode, what else can I do?
    If the blue indicator is the hybrid battery then the two of them combined would definitely get us home without turning on ICE but for some reason the Prime always wants to engage the ICE first.
     
  2. schja01

    schja01 One of just a few in Chicagoland

    Joined:
    Apr 22, 2005
    948
    612
    0
    Location:
    Chicagoland
    Vehicle:
    2018 Prius
    Model:
    Prime Advanced
    It’s all one battery. When in the Blue portion you will be in EV mode from time to time s/a the conventional Prius. So if there is a way to force a conventional Prius to not use the ICE that same would apply on the Prime. All current Prius have a EV mode but it’s more a suggestion than with the Prime’s EV mode.
     
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    83,244
    36,315
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    welcome!
    sorry, no. it is programmed to start the engine when you run out of wall charge. further use would damage the battery.
    anywhere to charge on your route?
     
  4. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    4,526
    3,425
    0
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Welcome to PC.

    Since you live in Canada it must be getting colder by now. If you recently purchased the car, you may get a better EV range next summer when the temperature warms up. Meanwhile, going into the winter, expect the EV range to drop precipitously. Depending on your routine driving habit, it is sometimes better to force the HV mode sometime in the beginning or in the middle of a drive than running out of EV range and having the ICE come on only a few miles before shutting down. With your current situation, the ICE does not have enough run time to complete the warmup cycle and you may be getting very low on your traction battery, both not so good for the car.

    I am in very similar situation as you on my daily routine commute with total distance of 35-37 miles to drive on a full charge. I usually run HV in the morning commute and save EV on my commute back with ~40% EV left when I get home. Yes, that forces ICE to come on, but unless you can get 100% of your trip on EV, I think it's better to have some EV range left when you finish the trip so you are not forcing the traction battery to go habitually low state of charge. Good luck.
     
    #4 Salamander_King, Oct 11, 2019
    Last edited: Oct 11, 2019
    jerrymildred and bisco like this.
  5. harhar

    harhar New Member

    Joined:
    Oct 11, 2019
    6
    1
    0
    Location:
    Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Prime Premium
    Well that's too bad, we're so close to avoiding any gas consumption.
     
  6. harhar

    harhar New Member

    Joined:
    Oct 11, 2019
    6
    1
    0
    Location:
    Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Prime Premium
    Nothing free, and the $2 minimum at the nearest charger isn't quite worth going out of our way.

    How long does it need? How would I know if we are low on our traction battery?
    I was hoping that driving the Prime would allow us to avoid using gas on our regular commute so we just use gas for longer trips, but you are saying this would be detrimental to the vehicle? What would using up our EV everyday first do exactly, the salespeople didn't mention anything about this when we told them our driving situation/requirements.
     
    #6 harhar, Oct 11, 2019
    Last edited by a moderator: Oct 12, 2019
  7. noonm

    noonm Active Member

    Joined:
    Feb 5, 2019
    436
    396
    0
    Location:
    NJ
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    Full charges (100%) or deep discharges (0%) can significantly reduce battery life: Battery Lifetime: How Long Can Electric Vehicle Batteries Last? | CleanTechnica

    To reduce that effect, pretty much as PHEVs/EVs, restrict the amount of the battery capacity that you can use. Based on my own experience and others on this forum, you can only "use" about 6.3kWh out of the total 8.8kWh battery in the Prime. That corresponds to about a 11-12% charge on the low end to a 87-88% charge on the high end.

    As far as I know, there is no way to bypass this restriction. However, if you could, doing this regularly would shorten the battery life, although how much it would shorten is unclear.

    Besides the hypermilling you are currently doing to increase the range, the only other option I know is to "pre-condition" (i.e. have the car cabin heat/cool) while its still plugged into the charger. Warming the car up appears to be the biggest drain on EV range in the winter time (dropping mine into the ~20 mile range), so this can partially offset the impact.

    I've also seen the defrosters eat up valuable electrons, so if you can clear the ice without or minimize the amount of defrosting you do, that would also help.
     
  8. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    83,244
    36,315
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    how many km is your commute, one way?
     
  9. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    4,526
    3,425
    0
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    It depends mostly on the ambient temperature. On a hot summer day, the warm-up cycle required to bring the catalytic converter and other pollution controlling devices up to optimal temperature is minimal. During summer, I've had the warm-up finished in less than a mile, but on a very cold winter day, it could take 5 miles or longer. During this period, there is really nothing you can do to improve fuel efficiency. Just drive normally and let the computer do the work. When you run out of EV range and ICE kicks in, your battery SOC (State Of Charge) is at 14%. After switching to HV, until ICE finishes the warm-up cycle the car continues to use the traction battery power. This is the time when, even though the ICE has already stared, the traction battery SOC can dip down. From other reporting, it can get as low as 7-8%.

    If you reach your home and stop your car at this point, your traction battery is at this low SOC. It is a known fact that deeply discharging and leaving it at a discharged state is not good for a lithium battery's longevity. What we and for sure Toyota salesperson do not know is how this will affect the longevity of PRIME's lithium battery. I am sure if you do this only once in a while, it is not a big deal, but if you keep doing this day in and day out for years, it is quite conceivable adverse effect will result. I certainly do not want to find out the effect on my car. That's my take.
     
    #9 Salamander_King, Oct 11, 2019
    Last edited: Oct 11, 2019
    jerrymildred likes this.
  10. harhar

    harhar New Member

    Joined:
    Oct 11, 2019
    6
    1
    0
    Location:
    Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Prime Premium
    It's 25km one way. There are two big hills on the highway and another hill back up to our house that seem to take the biggest chunks of the charge.

    Ok, the traction battery is the blue bar? This one doesn't drop down and is almost always full when we get home - the final 5km is all uphill so when the EV is used up (pretty much right before the 'final ascent') the ICE kicks in and is pretty much on until we get home. I guess that's just mountain living for you.

    That's a good idea, we'll have to start doing that now that it's getting frosty overnight. It's too bad I can't use Entune to do it before we go outside - you know if they had told me that only the top model has that option I might have considered it since we already went for the Upgrade (just not the Technology). I still don't understand the point of Entune.
     
    #10 harhar, Oct 11, 2019
    Last edited by a moderator: Oct 12, 2019
    bisco likes this.
  11. harhar

    harhar New Member

    Joined:
    Oct 11, 2019
    6
    1
    0
    Location:
    Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Prime Premium
    On the subject of pre-conditioning I just realized the A/C button on the key fob should work for this right? Does it use the last cabin temperature setting as a reference point? I assume you can't defrost with it though.
     
  12. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    6,255
    7,843
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    As @Salamander_King said above, the warm up time is variable. You can experiment by putting the car in HV mode well before the EV range runs out. Note the odometer reading. When the computer decides the system is warm enough, it will shut off the engine. That's how far it takes under those specific driving conditions. Colder weather and slower driving take longer while warmer weather and faster driving are quicker.
     
  13. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    4,619
    2,959
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    Yes and no. It's possible because Ford has utilized this concept since 2013 in my C-Max Energi. They call it EV+ and it uses the GPS to learn one's home, work, or any frequently visited spot and will allow the car to dip into the HV portion of the battery and maintain EV mode to the destination even tho' the meter has reached zero EV miles left. This feature has its limits of course but it works very well for destinations with a charger (home). (y) Nothing like the ICE firing up 1-2 blocks from home..... :mad:
     
    jerrymildred likes this.
  14. harhar

    harhar New Member

    Joined:
    Oct 11, 2019
    6
    1
    0
    Location:
    Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Prime Premium
    Too bad the Prius can't do it yet, this is precisely my situation.
     
  15. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    83,244
    36,315
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    mine too, sometimes. i was hoping they would have added it to prime, after all the pip complaints, but no luck.
     
  16. vvillovv

    vvillovv Active Member

    Joined:
    Mar 19, 2013
    834
    293
    0
    Location:
    NY
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    There are two things you can do to make the entire trip in EV mode. But to answer your question about forcing the car to use more of the battery pack for high discharge rates than toyota prime programming deems the high discharge rate limit, the answer is NO, you can't force more from the battery pack after that programming limit is reached.
    The two ways I mentioned above are really only one, but have two different methods of implementation.
    The one is SLOW DOWN.
    The two implementations are,
    Slow down even slower than you are already driving your whole trip.
    You can try Creep Home mode, but I doubt it will get your 5K no matter how slow you go.
    I believe the Creep Home mode starts at around 10 mph and decreases as you drain more charge from that hybrid section of the state of charge display on your dash.

    Be warned that trying to fool the cars computers that way can have negative results both initially and in the long run. Some with warning messages displayed on the Dash and some without.
     
  17. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    4,526
    3,425
    0
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Once you reach EV range zero and the car switches to HV, the battery charge bar in MID stays relatively constant, but they do depleate one or two bar during operation. You can use OBDII adaptor and phone app to monitor the real traction battery SOC. According to some reports, you can get down to 7-8% SOC level during HV mode.

    Uphill indeed eats up EV range very quickly. You can't do anything about the uphill to your home, but if you said you have two hills on the highway. If you can take an alternate route to avoid the highway and two hills, you hit two birds with one stone. You can slow down and you will avoid uphills. It might be worth exploring. You also said the trip is 25 km, that's 50 km or 31 miles. That distance is very doable all on EV during the warmer month without using any AC. I can get 40 miles of EV range on flat roads, on my regular commuting with 150 feet elevation changes, I can sometimes get entire 36 miles on EV, but not always. Of course, going into winter, the EV range will diminishes to below 20 miles, so I can only do one way of my regular 18 miles commute all in EV.
     
    #17 Salamander_King, Oct 12, 2019
    Last edited: Oct 12, 2019
  18. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    6,255
    7,843
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Or while pulling into the garage as happened to me a couple times.
     
    vvillovv likes this.
  19. andy musetto

    andy musetto New Member

    Joined:
    Nov 14, 2019
    1
    0
    0
    Location:
    NJ
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Premium
    my 2019 prime switches from ev to hybrid even when there is ev battery left; don't know why
     
Loading...