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EV Mode Drains Battery Faster After Cancelled?

Discussion in 'Prius c Fuel Economy' started by Hodr, Aug 1, 2013.

  1. css28

    css28 Senior Member

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    Do your car a favor.
    Start the engine before you drive anywhere (just press the accelerator for a moment after the Ready light comes on). If you're not in a hurry, take your time to fasten your belt, adjust your mirrors, etc. then get underway. I prefer to wait until stage 1a is complete (a little less than a minute of engine running) before moving the car.

    The car will be peppier because it's transmitting engine torque to the wheels and the battery charge is high enough to help.

    As fun as it is to pretend that you have an electric car, the truth is that you don't. Every kilowatt hour that you use with the EV button pushed has to be made up (with interest) by the engine later on.
     
  2. NewPriusC

    NewPriusC New Member

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    image.jpg

    Question: why my EV mode still on when i already park my car? Btw, i didnt press the EV button. Anyway, this is the best MPG i got so far for a trip!
     
  3. Species5618w

    Species5618w Member

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    The stealth EV mode is on as the engine is not running.
     
  4. coyote303

    coyote303 Member

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    I'm not sure I agree. What gives a hybrid its mileage is that it captures energy that would otherwise be lost. Some, most, or all of the energy that needs to be "paid back" will be done so with energy that would be lost on a standard car or, for that matter, lost on your hybrid if not used.

    My mileage is really good when my driving allows my car to use up this captured energy efficiently. There are times my mileage could be better, say, going up a long hill if I could "tell" my car that there is a long downgrade just ahead so proceed to use up the battery. When you push the EV button, you are essentially telling your car to go ahead and use up the battery.* Unless this driving is going to be followed by a long uphill or high speeds, it's likely the "debt" will be efficiently repaid with a net MPG gain.

    *I'm not suggesting EV button mode is good for going uphill; it's not. My point is the car's computer has to be conservative using the battery since it doesn't know what might lie ahead. I'm saying unless you're getting ready to merge onto a freeway or unless your garage is at the bottom of a long hill, EV button mode should be a net MPG gain.
     
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  5. css28

    css28 Senior Member

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    In your example if the anticipated downhill afterward were long enough that you'd exceed the battery's regen capacity during the descent (and thus have to use brake friction or "B" mode backdriving of the engine) then you could make a limited case for it.
    Also if you're driving at speeds in which using the ICE is less efficient than draining the battery in EV only to recharge later in the drive then EV makes sense--but the car will revert to EV in that case anyhow, without using the override button.
    The other, less obvious part of your long hill situation (other than the fact that a standard Prius won't pull very long at all on a hill using EV alone) is that by routinely deeply cycling your battery you probably will shorten its life slightly.
     
  6. It's probably been answered, but I've also seen this and yes this is normal. The hybrid is programmed to warm up the engine, but still use battery to propel the vehicle... so, during this phase, the higher your green arc is, the faster (higher current) discharge and it's inefficient. You would still have to wait the mandatory warm-up time before the generators kick in and the engine (rather than all battery) propels the vehicle.

    The other thing I've noticed recently is that say you go to a supermarket, 45 minutes later you come back hit the EV button and off you go. Same thing is likely to happen (if your engine has had enough time to cool off).

    So, I usually don't bother with the EV button on a cold engine, unless I plan a very short and very short trip, and those do happen every here and there.
     
  7. hill

    hill High Fiber Member

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    Install an EBH, and avoid the 1st 1minute/10minute warmup (turns on temps in your area).
    PriusChat Shop : Toyota Prius Engine Block Heater [Prius EBH] - $59.00
    The EV button in a non plug-in vehicle is what it is. Pull from the traction pack (at startup or later), and you gotta pay the piper. Your HSD has to be repaid for any/all withdrawels. All energy in the pack has to come from the ICE ... whether you climed to the top of a hill then regen on the down side, or whether you're practicing P&G.
    .
     
  8. coyote303

    coyote303 Member

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    With this logic, why would they even make hybrids? Of course all power initially comes from the ICE. The answer is because under many driving conditions, you capture energy that would otherwise be lost. So, more often than not, you are "paying the piper" with excess funds.
     
  9. hill

    hill High Fiber Member

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    Not " more often than not " ... but close ... 'sometimes' ... or, "under some driving conditions"
    And that's why they build hybrids. ... because of the "sometimes" conditions .... That's all it takes for a hybrid to be more efficient than a standard ice
    .