The battery is a 95 cell 25AH Lithium (3.7V per cell nominal). That's almost 200A at over 350V (almost 400V at full charge and no load).
I have long suspected that the available electrical power was speed limited by a fixed table. You have confirmed (not disproved) that hypothesis. Bob Wilson
The non conventional trend of the power curve may indicate that the 'dual motors' in EV mode is not engaged from the beginning but rather a speed controlled feature (engaging at ~40 mph?). The ~58 kW at around 30 mph (as compared to 53 kW rating of MG2) may partially be explained by data collecting and processing accuracy, but MG2 may operate slightly above its power rating for a second or two due to a lag in the current limiter intervention?
Perhaps the first step is to map MG1 and MG2 rpm as a function of vehicle speed. Knowing the P610 gearing may provide the answer. Next see if we can find SAE or other credible sources of MG1 and MG2 performance curves. But in the meanwhile, I'll see if I can find Scangauge II definitions that give torque and rpm for MG1 and MG2. Then I can replicate the 30 mph maximum acceleration with an iPhone video record the data including the indicated speed. Bob Wilson
That's why I use the name "ePWR." I don't claim to understand the technical and mechanical aspects of the Prius, but I sure enjoy the smooth & quick acceleration of my 2016. Thanks for the interesting thread.
I am surprised to see that the ICE of the Prius beats the electric 120 hp motor of the Ioniq by nearly one second when it come to 80-120 km/h time ! With EU Prime you can also floor the pedal using normal pressure,but if you press it real hard you can force the ice to fire up just in case you get in an emergency situation and a bit more power is needed . Is that different to the model in the US ?
I'm not following you, Bob. Looks like the two runs are different whether power versus speed or power versus time (oops...just noticed the vertical label on the second one is wrong - should be Power (Watts)).
You're right! Yet both show that curious dip that climbs up again. Now I'm wondering if it something else: temperature? battery discharge? That is a puzzle. Makes me wonder if there is a power level that does not show that curious dip? Bob Wilson
So, I've been wondering why the car doesn't perform in Ev mode like it should. When asked, the chief engineer said the car should put out 76kW in Ev mode. The European specs say it's limited to 68kW in Ev mode. I'm only measuring 61-63kW peak. Could be that the European specs are correct, but only refer to battery electrical power, which would then have to be multiplied by power electronics and motor efficiencies. Call those two 90% combines and 68kW*0.9 = 61.2kW. Motors are *always* specified by shaft output. In this case, it could be that my assumption that this is the case for the car as well is wrong, and the 76kW number from the chief engineer was wrong, and the 68kW number from Europe is electrical, not mechanical.
Ok, Ok, I'll go do some benchmarks today too. I'll use an accurate accelerometer and see if I can get the me and the car weighted. Then I'll do some maximum accelerations and integrate to derive the speed and calculate the kinetic energy over time. Then I'll use the EPA coefficients for the drag power. Sorry, I've been 'lazy' about this. I note there are some iPhone apps that use the built-in accelerometers to do the same. I'll survey them see if one makes sense. Bob Wilson
For those who live at high altitude will notice Hybrids in general feels faster compared to N/A engines. ICE needs fuel + oxygen to work and the oxygen gets less the higher you go up thus N/A engines lose about 30% power at high altitudes. Toyota Corolla 0-60mph 9.2 seconds With 30% loss it becomes: 13.1 seconds Yes the Prius Prime is faster* Cheers! *in Denver, CO 5280 feet elevation
You have to be careful about these altitude claims. First, oxygen concentration doesn't change with altitude. What changes is barometric pressure, and thus mass per unit of volume (density). Since a regular engine is volume-flow limited, rather than mass-flow limited, density is what counts. And density goes like this: ft density ratio 0000 100% 1000 97% 2000 94% 3000 92% 4000 89% 5000 86% 6000 84% 7000 81% 8000 79% 9000 76% 10000 74% 11000 72% 12000 69% So, in Denver (between 5,000 and 6,000 feet in most places), you're down about 15% for a naturally-aspirated engine. On an engine that has a turbo or supercharger, the ratio will be less.
Wow good to know the ratios! So about 15% loss at 5000ft. I have driven a Honda S2000 n/a engine all the way up to Mount Evans just west of Denver @14,000 ft highest paved road in America.
You wonder what the fuel pump and injectors are doing at that 14,000ft (wow!) elevation!! Cavitation Central! .
In the Denver area, the three octane levels you can buy are 85, 87 and 91. I think at sea level those same levels are 87, 89 and 94, correct?
I've re-run the 0-60 test in Hv mode. Here's a comparison. Keep in mind where I live - this was done at nearly 6,000 feet of altitude. Ev: 20 1.96 30 3.45 40 5.57 50 8.40 60 11.91 Hv: 20 2.11 30 3.53 40 5.39 50 7.82 60 10.62
Pretty slow car. Fast enough for me but it is a bit disappointing to know that it’s slightly slower than the gen 2.
At my altitude, it's much faster in Hv mode than the gen 2. I measured my gen 2 in the same location at 12.2 seconds.
Yeah, BUT, he did say 6000 ft.!!! That makes a HUGE difference with a non turbo car!! My Alfas would drive like stuck pigs when I would visit my folks in Idyllwild, CA, at just over 6000 feet! Sea level performance should be better. My real world Prime experience is that I can pass or keep up with anything that isn't all out racing. .