Is Gen 5 Prius really better-looking than Gen 4 Prius Prime?

The Touring and Limited trims had P215/45R17 tires. The Eco and the rest had P195/65R15s. The larger and heavier trims were very likely what was used for the non-Eco mpg tests.

The gen 5 uses the same battery, has a greater weight difference, with the same 2 inch increase in wheel size, though the tires stay the same width. Its LE actually has a slightly better improvement over the other trims than the gen4 Eco.

The difference the Canadian Camry Hybrid LE and the US LE fuel economy is greater that between the Canadian LE and the XLE and XSE, with heavier weight, bigger wheels, and NiMH battery.

Any Coulombic efficiency advantage to Li-ion appears to be small. Considering the slow acceleration and deceleration rates of the EPA tests, it might not even show up there.

 

What evidence do you have that they didn't?

The tested weight of the 2020 Eco was 3250, and the other Prius used was 3375.
Data on Cars used for Testing Fuel Economy | US EPA
That's 240 and 300 pounds more than listed curb weight. The 60 pounds difference is from the other test Prius being equipped with all the options.

The coulombic efficiency of NiMH can approach 90% with fast charging, and the energy efficiency of Li-ion will drop with faster charging(your source). Then the numbers cited are general ones, and not the actual ones for Toyota's batteries.

Since you refuse to address the points I raised with the Camry and gen5, why is the Eco the only one with a higher rating? It isn't the only gen4 using the Li-ion battery. It appears most did. So why aren't they rated as high as the Eco if it is all about the chemistry as you claim?

 

I can't imagine anyone not loving that color.

 

Those are applications and certificates for the emissions. Only the cold test had fuel economy results. The different batteries mean different emission systems.

In the fuel economy database for 2016, there are three test Prius. A Two, Eco, and another from the Eco's test group.
Reported results for the Two.
city test: 64.9 and 77.3
highway test: 63.6 and 76.1

The Eco
city: 71.1 & 78
highway: 66 & 71.2

The Other was only used for the cold and air conditioning tests. Which weren't done with the Eco. I'm guessing it is another Eco as the first only did the high speed in addition to the base city and highway, and these cold and A/C results are better than the Two.

Looking further at the emission paperwork, These three test vehicles were used for those certifications. The Eco results were allowed to be used to cover the others for emissions.

Toyota surely did do some fuel economy testing with the others. They couldn't have been notably better if they decided to group them with the Two for window sticker rating.

 

Yet Li-ion, plus smaller wheels, thinner tires, and lighter weight, only gets the Canada Camry Hybrid LE 4.2% better fuel economy than the higher trims to the Eco's 7.7%. The even smaller wheels and thinner tires of the American LE get to 13%. Which is what started this side discussion, Toyota putting more effort into the American LE to get above 50mpg.

 

Later model years in the fuel economy database do differentiate between the Priu s and Prius Eco.

The Camry Hybrid LE already uses Li-ion. Looking at the US and Canada versions with the XLE/XSE shows that wheel size plays a bigger part in the LE's better efficiency than battery chemistry. Then much of the improvement of this gen from the previous came from the upgrade in engine technology. The 2025 X trims might reach the 50mpg hurdle from the mid-forties they are at now. The LE could beat the Prius XLE, but not the Prius LE. It won't be cheaper than the Prius.

 

Maybe worth noting: in Canada (shades of Henry Ford?), you can get any gen 5 non-plug-in Prius you want, as long as it has 19" wheels, and AWD.

 

Along that line, Japan can get any Prius Prime, as long as it is the top trim.

 

That does not wash. The Prius is close to the same size as the Camry. The term 'tiny car' should be reserved for the sub-compacts. A "Think" is a tiny two seater. So are some of the BMW models. The Tesla Model 3 is smaller than the 2024 Prius, yet I'm not seeing the term "tiny" applied to any of the Tesla models.

 

Except the hybrid LE in the US isn't using the same wheels as the ICE LE, which is why I was bringing up the Canadian hybrid LE.

With the ICE LE getting a 3.2% improvement over the XLE, that leaves less than 1% due to the battery, as there is also the engine efficiency of the Atkinson cycle in the hybrid.

The gen5 is an EPA midsize like your gen4. The total volume is almost the same as the Camry's. It just has more cargo space and less cabin.

 

I remember from my youth that the easiest way to change the performance of a car is to change the back end gear ratio. The easiest way to change the gear ratio? Simple. Put larger diameter tires on the driving wheels. For each revolution the car will move further.

On my car, it looks like the 19 inch rims with the lower aspect ratio tires move the same distance as the smaller rims with a higher aspect ratio.

 

This is news to me; I thought they used 15” rim model. Could be wrong.

With Gen 3 and 4 the 17” rim/tire combo has slightly smaller OD, versus 15”. With Gen 5 it’s the reverse: 19” OD is greater than 17”, and the difference is more, close to 1/2” for the OD’s IIRC.

 

My math was not wrong.
I only had numbers for the 2024 Canadian models so used 2024 US Camry, which has no 16" wheel models listed. I also converted the the Canada L/100 km to standard mpg and rounded them like the EPA in another post, and used those figures(Canada LE is rated 48 city/49 highway/ 48 combined).

The 2024 18" is 31mpg combined compared to the 17" 31mpg. Making the smaller wheel improvement 3.22%. 18" to 16" is a 9.7% improvement. That extra inch in wheel size reduction and skinnier tires triples the one inch difference improvement. Little weight changes to unsprung weight have a bigger impact than the raw numbers imply.

This all started cause I said Toyota put more effort into the US Camry Hybrid LE than the Prius L Eco(post #373). They just swapped the battery from the NiMH in the fleet sales Prius L. The Camry got the battery swapped and got the wheels from the fleet Camry. Toyota Canada didn't feel compelled to use the cheap wheels on a car that might be coming out of the same factory.

 

Mea culpa. I did not double check any of the dimensions for the 2024 XSE 19 inch tires VS the ECO tires.

Bringing it back to the thread title... no one said that they thought my 2017 Prius Prime looked great. They thought it looked different. They thought that it did not look like a Prius. A few thought that it looked more like a sports car than the Gen 3.

In the two months that I've had the fifth generation Prius Prime, I've had many compliments on it's over all looks, and many focused how good it looked with those rims.

Keeping it in perspective... I drove a GEN 1 Prius for more than 17 years and I liked it. I drove a Gen 4 Prius for 4 years, and I enjoyed it. I can only guess that my body type is close to what the Japanese use when determining the ergonomics for their cars.