2017 Prius Prime First Drive: Best Prius Ever

I can only see a pop up about the Prius prime constantly covering the right hand six of my screen...

 

Thanks for the Prius Prime review!

Do you know what sort of cooling system they have for the (big) battery? From what little I've seen so far, the answer seems to be air/nothing, which, as we saw on the Leaf, is a recipe for lawsuit...

So, then, best you can tell at least, chademo will not be available on the US version?

Oh, and, perhaps I just missed it, but any idea how soon it will be available in the US?

 

1) air, cannot be compared to leaf, totally different problem.

2) no chad.

3) early 2017.

 

The Leaf's biggest problem, as I understand, is that it truly has no cooling.

The Prime actually has air cooling, which should help a lot.

 

it has worked fine for the pip so far, plus, toyota takes other precautions and have different chemistry.

 

Leaf's chemistry has been upgraded. Those issues of three past area of no concern anymore.

 

My understanding is that even with the upgraded chemistry, degradation is rather high.

 

I haven't heard that from owners of the newer models.

 

Isn't it a little too new for any definitive conclusions? That being said, from some literature I understood they at least allow ambient air circulation in their newer design but it's not forced and it seems a little tight. I've never liked their battery design and until they have some kind of active thermal regulation (other than adjusting internal resistance), I for one will be ignoring their EVs and plug-ins for purchasing consideration.


Unsupervised!

 

The new chemistry has already seen as many miles as the old when complaints became a serious issue for Nissan. Remember, the software has been adjusted as well. So, I'd say no.

Of course, there really isn't anything definitive. After all, we have no idea with any of the plug-in vehicles what "normal" aging is. That makes it difficult to gauge "excessive" to justify warranty replacement.

There's the education of owners causing inconsistent comparisons too. Some are aware of "cold soak" benefit and avoiding 100% recharges in stressful conditions.

And speaking of battery longevity, I'm working to provide updated videos of my Prius PHV just prior to getting my Prius Prime. Here's the first of the new ones, featuring a 13.9 consecutive-mile EV drive on my commute to work last week:

 

The Leaf has a fan, and a resistant heater to keep the electrolyte from freezing.
The pack in the Prime and other PHEVs are smaller than the Leaf's, so air cooling is fine. Plus, they can switch to ICE in the case that the battery does manage to get too hot.

 

Source link?

The original LEAF pack was completely sealed and passively cooled by radiating via its outer metal case. There was no fan inside. I don't follow the LEAF closely anymore but I'm not aware of this design having been changed in the LEAF. A quick search on mynissanleaf.com of threads and posts from 2016 did not indicate that anything has changed.

Nissan did add active air cooling using a fan to the battery pack on the e-NV200 utility van which uses the LEAF propulsion system but as far as I know they have not integrated this air-cooling modification back into the LEAF itself for whatever reason.

 

It was here that I heard it in a discussion between active and passive cooling. Guess, I should have questioned the source then.

Hopefully Nissan has wised up in regards for the gen2 Leaf. I don't see how passive cooling will be practical for large packs without bulky packaging.

 

I don't understand this. I would think the electric system would contribute in HV mode similarly to the way it does in EV mode, thus HV mode should be at least as fast as EV mode. Are you comparing EV/Prime to HV/HB or EV/Prime to HV/Prime?

 

In EV mode, the Prime is driven by both MG2 and MG1. In hybrid mode, it is MG2 and the ICE.
With the lag for the torque to build up from the ICE in the equation, the car will be faster off the line in EV mode, since it will be applying more torque at zero rpms. When accelerating to higher speeds, the times will be closer together between the modes as the ICE is contributing more, and the torque starts to decrease from the motor.

 

The ICE is way more powerful than MG1, right? And the Prime MG2 is more powerful than MG2 in the HB, right? Does this mean the Prime is faster accelerating than the HB in either mode?

 

The Prime has the same MG2, MG1 and ICE, which, from an economic point of view, is quite good for Toyota. The only differences are the addition of a one-way clutch, which in EV mode (not HV mode) allows the dual mode drive system to operate, and an adapted battery power management. The dual mode requires a high enough traction battery state of charge (SOC) (I understood 40%, but may be wrong).

This graph shows the initial acceleration is indeed better in EV mode.



The combined power of the MG2 & MG1 is 103 HP (torque must be pretty high from the start). It is, however, limited to 91 HP by the power the HT battery can deliver. After that, both modes roughly accelerate the same.

In fact, the HV mode may be tamer than that of the 4th gen Prius, because of the added weight, but so far, no data have leaked on that.

Jan

 

They have different power curves. But yes if the ICE is at speed then yes it's way more (>3 times) powerful than MG1 as well as MG2 except combined but the total power output is limited by the battery. So the ICE can output more power than the battery (72 kW vs 68 kW) although the battery output is not quite written in stone yet.

Nope. They are the same 53 kW motor.

Nope just in EV mode is it faster up to a certain speed (~40 mph).



Unsupervised!

 

IIRC, there are other electrical power limiting variables as well. For instance - motor running hot (hot days, elevation driving/full loads etc) , may cause ECU's to regulate power output, similar to when traction packs are approaching depleted status.
.

 

The ICE is more powerful, but the MG has higher peak torque, and it reaches it sooner. I don't know if any specifics are out on the the Prius engine alone, but around 2000rpm is likely the soonest it could reach peak torque; more likely later than that. A motor's peak torque on the other hand is at 0 rpm, and it decreases as the motor gains speed. That instant torque of the MG2 is what allows either Prius to be quicker than a comparable ICE only car when measuring from 0 to 20 or 40.

It's a time frame measured in seconds, in which the ICE has not reached the rpm for peak torque from idling yet. So the ICE, while able to produce more power, isn't producing its max yet. Going past 40mph, the ICE has reached full output, and the HB's acceleration rate about matches the Prime's EV one.

Which is faster in hybrid, I think will come down to the amount of charge in the Prime's battery. MGs are the same in both, but the MG2 is capable of outputing more than what the HB battery and ICE through MG1 can provide. A fully charged traction pack in the Prime means it could get more out of MG2 than the HB could. But the Prime is heavier, so without extra charge in the battery, the HB might beat it.