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EV on 0. Hybrid Battery stays full. Is there a way to force use it for EV? Where does regen go?

Discussion in 'Prime Main Forum (2017-2022)' started by ride43, Nov 21, 2017.

  1. ride43

    ride43 New Member

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    Prime Plus
    Sorry for the confusing title. I have a few questions. I think in general I might not understand the basics of hybrid mode. I understand EV, and can see the range and Green portion of the battery go down when driving, and up when regen braking.

    However, once the EV is totally depleted the hybrid battery seems to stay full no matter what. Shouldn't it use a little of it, and then let the regen braking build it back up? When it stays full and I regen brake is the charge not saved? I would have thought it might go to the EV battery if there was surplus.

    Another interesting observation: I was on the highway and my EV ran out and it went to Hybrid. I did not hear the engine very loud, and continued to drive what felt like EV mode and saw the hybrid battery deplete quickly. Then I pulled off the highway and when at a light it sounded like it kicked into charge mode (did not display charge indicator on dash) and the hybrid battery went to full. It seems that it did this to protect the engine, which was pretty cool.

    If not is it better to kick out of EV mode with a few miles to spare, so you can get excess regen charge saved up to the EV battery when available?

    So I wonder are there other situations where one could "force EV mode from the hybrid battery" if we only needed to go another mile or two on surface streets and knew we could plugin soon to build the hybrid and EV battery back up after?
     
    #1 ride43, Nov 21, 2017
    Last edited: Nov 21, 2017
    Andyprius1 likes this.
  2. Tideland Prius

    Tideland Prius Moderator of the North
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    1. Yes any regen in HV will top up the battery so you should be able to get some EV miles back if your descent is long/steep enough. I can't comment on the behaviour since I don't own a Prime.
    2. If you're in EV Auto, it might've started the engine earlier before the EV portion of the battery became depleted but I'm not 100% on this behaviour.
    3. If you drove around with a light foot like you normally do in a regular Prius, you might be able to use a bit more of the HV portion of the battery before charging up.
     
    #2 Tideland Prius, Nov 21, 2017
  3. PT Guy

    PT Guy Senior Member

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    This is a misunderstanding. EV means Electric Vehicle. That is the car running on the traction battery (the big battery that powers the traction motors). There is no "hybrid" battery. There is only the small 12 volt battery for lights, radio, powering up the system, etc., when the car isn't running.

    So...don't worry. Just drive. The system is smart enough to take care of you and itself. Even when the traction battery shows no charge, it has some charge. It'll get more charge when coasting, or braking, or sometimes when the engine is running without you doing anything except driving. It'll use that charge to power the traction motors sometimes with the engine off, or sometimes in addition to the engine. Don't spend too much time looking at the green & blue worms crawling on the multifunction display. Look at traffic.

    When I'm headed out on a run I know is longer than the traction battery will take me, I switch on EV Auto. That gives me gasoline power in addition to battery power when the system calls for it up hills and when I mash the accelerator pedal. It seems to give a bit better overall gas mileage. The only other thing I switch is the shifter to B when coasting on long downhills, and back to D all the rest of the time. That puts a bit more charge into the battery and a bit more regenerative braking.
     
    #3 PT Guy, Nov 21, 2017
    Last edited: Nov 21, 2017
    priuscatprimeguy likes this.
  4. Andyprius1

    Andyprius1 Senior Member

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    I have a plus and find that using eco mode going out preserves all of the home charge. On the return
    I use ev/eco and get phenomenal mileage’s. eg: To= 85-90 mpg // From= 189 to 199.9 mpg + Do not confuse this199.9 with what shows initially. What I quoted in from is real mpg, not some theoretical nonsense.
    This is all hill up/down to about 2000 feet, which makes it even more phenomenal!
     
    #4 Andyprius1, Nov 23, 2017
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