Should Plug-In Prius have an EV button?

If the shipping Prius PHV has similar characteristics and limitations, it definitely should. You could have scenarios where you want to save the charge for non-highway portions at the end, but are unable to.

Example: Your commute consists of getting almost immediately on the highway or a substantial portion in the middle yet you don't want to waste it on the highly draining highway portions (due to drag) but want to save the EV for the last part which is city. You can't w/o an EV button.

Many of the folks here on PC who did get to drive the Prius PHV (not me), expressed the same need. They mentioned they had to speed (go above ~60 some mph) in order to force it to not stay in EV.

BTW, were you intending to post the above article as Prius news or just posting a poll?

 

Or maybe have a 'Hybrid' button instead of an EV button. That way you can select the car to run as an existing hybrid Prius if required WITHOUT using the stored EV range.

Example - You live in the suburbs and commute 30 miles to the city. It would be more useful to run the car as a hybrid for the first part of the journey and then have the option to switch back to EV for the congested journey through polluted city streets.

The 'Hybrid' button would reset at every power down in the same way 'Power Mode' does on the existing Prius and maybe 50% of owners wouldn't bother with it, but it would give flexibility to those who would.

 

An EV/HEV switch is needed. People are going to drive more than 13 miles. People are going to drive in different conditions. People know their journeys better than the car. So, a driver override would help it be more efficient. It's fine if they put a minimum time on the HEV mode for reasons of emissions control.

 

This is exactly what I had in mind when I saw the thread title. There are going to be situations where battery charge will be wasted because of steep grades or high speeds at the beginning of a trip. With the ability to shut down EV mode, the battery charge can be saved for when it can be used most efficiently.

 

The HSI bar becomes the EV bar. It shows you when (exceed the bar all the way to the right) the gas engine will assist. It requires constant eying on the EV bar.

If EV button was provided and turned on during emergency acceleration, you forget that you were in EV mode. Wouldn't that be dangerous? These steps will delay:

1) Wth? Why isn't the gas engine assisting for full power?
2) Oh I am in the EV mode, huh!
3) Search for the button and turn it off

 

This should be a non issue. In EV mode there is already a built in override feature that will cancel EV mode and begin ICE assist when power demand reaches a specific threshold. I think the point of this thread is to determine interest in being able to completely disable the 2 dedicated plug-in batteries until such a time that the driver decides to engage them. Once engaged they should still be subject to the built-in override system if full power is needed.

 

I agree, Prius PHV should switch back to EV mode even after the gas engine assist. You would think it will operate in HV mode once the gas engine comes on right? Nope.

The prototype Prius PHV had a "super HV" mode. It is a transition mode before the battery is discharged to operate in normal HV level. This super HV mode can go 60 mph with the gas engine off but the gas engine is more sensitive to assist. This is basically a Blended Discharge (BD) mode. BD provides very high MPG!

 

I want that feature too. However on the flip side, if the driver forget to enable the sub-packs it defeats the purpose of plugging in. I would bet that human nature will overestimate and will have extra charge when reaching the destination most of the time.

I am sure Toyota will have the data from testing the prototype.

 

I like the idea of a forced Hybrid mode button for saving the battery charge somewhat, but an EV button is kind of redundant as that's the mode it should default to when there's a full battery.

 

Good point.

 

i'll put it this way, if prius doesn't have it and someone else does, i'll be looking at the other one. i don't know what the epa requirements are, but if possible, i would like a plug in hybrid that lets me drive in pure ev until the computer says the batteries are too low or some other necessary reason. i don't like the idea that the engine has to warm up every time i leave the garage.

 

It doesn't. Prius PHV always starts in EV mode. The gas engine doesn't start until you exceed the EV bar (moving in real-time).

See this video below. In city driving, you don't utilize the EV bar more than half most of the time during acceleration.