ICE in EV Mode ... Again

just so you know........my man boobs are as flat as the road I drive on, so no regen

 

What !!! You admitted the other day that you had "man boobz." Are you now changing your story to say you're as flat chested as say, Twiggy?

OK...you, you, you story changer. Your screen-name is now Priustwiggy. And your T-Shirt front will now say, "THIS SPACE RESERVED FOR MY TWIGGY CHEST BUT I STILL HAVE A 55 GALLON STOMACH WHICH RESEMBLES ONE BIG BOOB. JUST LOWER."

 

yup

but, hey, no regen! no ICE!

 

you can send me p/k's shirt.

 

DA WAN DAT SAY'S NO REGEN ON FRONT N NO REGEN ON BACK?

 

mine can say 'too much re-gen' on the front and 'too much estro-gen' on the back.

 

Yup, I've seen the same sort of low figures on short trips when the ICE fires up due to low temps/battery protection scheme. Luckily my normal daily commute (28 mi one way) is long enough to absorb some of the loss- I get about 68-72mpg at the end of my commute when the ICE fires up early. If the ICE stays off till I need it- I still get 81-85mpg even in the cold with snow tires (X-Ice Xi2) on.

Agreed. There must be a better way to handle possible regen overcharge...

 

i think i'm getting a handle on it, but obviously, the pip has the upper hand!

 

Neither. That's why I keep asking questions... which unfortunately continue to be misinterpreted as something other than learning details of how the system works so they can be shared with others later.

The engine started simply because the battery-pack was too cold for the draw requested. The road was flat and I was slowly accelerating. With the energy-bar only in the middle and the a few percent of full capacity already consumed, it was very clear that there is a third scenario at play.

I've seen that a number of times now, all from the same situation... the Prius sitting for several hours in temperatures below freezing. It makes sense to ease the burden on the pack for longevity and in most cases you'll need the engine for heat or acceleration anyway.

We know there's a city mode available, where the engine can be suppressed more. It's entirely possible the time schedule for offering a dynamic enough range our particular market simply wasn't realistic. After all, Nissan wasn't able to deliver a cold-weather package immediately upon rollout. With the next generation of Prius so close, it's not that much of a stretch seeing resources carefully chosen for short-term use.

 

certainly understandable when batteries are at a temp below which engineers deem safe. my question is, how long does it take to warm the engine to get heat to the batteries, and how does it get heat to the batteries if you don't turn the heat on to warm the cabin? or is it just using ice for motive power to decrease battery stress?

 

It's more a matter of longevity rather than safety. Warmth of the batteries does seem to be a key component too. I disrupted the recharging last night after the Prius had sat cold for a few hours, knowing the only warmth would be from the act of recharging itself and that moment would be peek. Sure enough, I was able to do the same drive without the engine starting despite the sub-freezing temperature outside.

 

How does warming the engine get heat to the batteries?

Mike

 

The battery's thermal regulation is a fan and the cabins air temperature. Personally, I'd be running the heater for a comfortable environment for both me and the battery.

 

PiP battery is cooled/heated by two fans. They draw air from the cabin. The fan speed can be set by Torque app so you could preheat the battery with some external heating element held close to the battery air intakes. I have never tired it and don't try it unless you know what you are doing. I have set the battery fan speed and I can hear it revved up so I know that works.

The best way to heat the battery (without tinkering) is to run the cabin heat, let the ICE run. When the cabin and battery is up to the temp, it should allow more EV operation later in the trip.

 

doesn't running the PIP in EV warm up the batteries also? The chemical reaction caused by discharging the batteries during EV travel.

 

The heat generated from discharging battery is very little. I think about 10-15% is loss through heat. So out of 2.7 kWh usable energy, that'll be very little energy for heat.

 

Good point, still doesn't explain why I can drive all EV even when outside temps are 23 degrees

 

you all are missing the question. if the engineers decided to have the ice start when it's too cold for the batteries for whatever reason (longevity, safety, performance, etc.) the heat from the ice doesn't get to the batteries unless you turn up the cabin heat which will then be sucked in thru the fans. this requires something from the driver that the engineers didn't decide to control. just like a/c is good for the batteries when it's really hot out, it doesn't come on automatically. so, is ice start up really a function of temp?

 

Well, the manual claims it is

 

doesn't it say 'may come on under 14 degrees'?