Volt vs. Prius C, Prius and Prius PHV

What's the x-axis?

 

Good stuff. Your indicating a Versa Note and a model S. Which vehicle types are you referring too? Are there no startup costs when installing chargers at the home for the plug in models?

 

pip comes with a 110v charger, but they recommend a dedicated circuit. not everyone adheres to this, but you're pulling 11 amps or so and you wouldn't want much else on it.

 

Is the Volt still prone to catching on fire spontaneously?

 

prone maybe a poor choice of word.

 

Apologies....

Still not a fan of GM products

 

i hear ya. i'd be more concerned about who's gonna bail them out next recession.

 

Spontaneous fires have never been an issue, that's just haters hype. The only volt fires were from a totaled car, drained of gas, but left sitting with a fully charged battery for a few weeks. (Ignoring the manufactures process for depowering). Even given that GM has upgraded the battery tunnel so now one cannot even get the fully totaled car to have that effect. Multiple prius's did, however, spontaneously catch fire and burn during huricane sandy (from saltwater infiltration). Neither of these is anything to really worry about.

 

Good information. Make a list what you want in a car & go with that. For me had to have good back seat room. The volt does not have that. But a friend has a volt & it's a cool car.

 

That is a scary thought, but a very good point brought up.

As taxpayers, will we again be seen as "suckers" by Congress and produce another Government Motors bail out?

When will people (taxpaying voters) start petitioning, calling, emailing their elected officials and say: NO.

DBCassidy

 

The only Volt fires should of never happened in the first place. Plain and simple.

What your statement is saying proves the lack of common sense in the alledged totaled Volt. First responders always disconnect electrical power from a crash. That is SOP.

It does no good to have a upgraded battery tunnel if the power can not be easily disconnected.

GM, again, falls flat on its' face for poor communication to first responders safety. even before the very first Volt was bought by customers, power disconnection classes should have been givened to first responders concerning the Volt.

Shame on GM for not being proactive on this!

DBCassidy

 

I had no idea just how limited the rear seat in Volt was until playing with one at the State Fair a few days ago. On my previous in-person opportunity, I only looked at legroom. Seeing Volt offered nearly 2 inches less room for knees (specifically 1.9") quickly ended my check. I didn't bother to look at anything else. It was obviously smaller than Prius. I should have continued with a detailed inspection.

Looking at room for feet. I noticed just how low the back of the front seats were in Volt. The top of your feet get pressed against it. There's no extra as there is with Prius. That discovery came as quite a surprise. I hadn't ever considered that particular comfort measure.

Another totally unexpected observation was noticing how low the top of the door was. I'm just 5'8", an average size man. So, finding out I'm too tall is quite out of the ordinary. When I turned to look out, all I could see was the roof of the car. To see out the window, I actually had to duck down. That certainly isn't the situation in Prius.

Last but not least, there's the lack of a middle seat. Some families, especially those who children have friends, will find that too much of a compromise. That extra seating comes in handy from time to time.

Long story short, the appeal to mainstream consumers is clearly in favor of the regular model Prius (and the plug-in). Prius is a midsize car. Volt is compact. There's no contest which one offers more rear seating room. It's strange how GM decided on a size which clearly limited its appeal to the masses.

 

GM added reinforcement so the coolant will no longer spill into battery compartment, for a specific test.

This does not mean it will be fire proof in all situations. There is additional risk in cooling the battery pack with liquid.

Plugin hybrids from Toyota and Ford are air cooled so they don't have that risk. Even a full EV like Leaf is air cooled.

 

The liquid cooling adds expense too... which hasn't been justified yet.

How much of a benefit does that truly provide? What's actually needed?

We've seen the overkill situation in the past.

 

Of course its not fire proof, no Li-ion battery is. Once it is hot enough and exposed any li-ion battery will burn, and burn very aggressively.


The reinforcement was added so the pole test crash does not crack the battery pack, not just so the liquid will no longer spill.


Liquid cooling only presents a risk if
1) the battery is not depowerd after an accident (which it always should even if air cooled -- its dangerous to leave high power in a crashed vehicles). Disconnected (as is automatic in a crash) is not the same as depowered.
2) the coolant is provided time to corrode elements. It took 3 weeks for the volt coolant to cause a problem. Furthermore any fire-surpression chemicals, including just water, could cause similar problem. That is why cars swamped by sandy caught fire.

Given that the gas tank in a crash presents far more of a risk, worrying about the battery is just FUD.

So the real issue is that after a crash a battery should always be depowered, just as it gas tank should be drained.
I've see NO material from Toyota or Ford suggesting air cooling serves any purpose other than reduced cost/weight.
Can you provide one suggesting the use it "so they don't have that risk".

Well lets see. Nissan, who is using just air cooling and the only other manufacture with enough battery and enough deployment to allow meaningful conclusions, has had serious degradation issues with air cooled batteries. Multiple owners in AZ have lost more than 15% of their usable range. Volts have not lost much at all (a few at ~2% loss), even though they have been in the same regions for the same length of time. Since End-of-life for a battery is generally considered when it reaches 20% loss of capacity, the leafs in AZ could be going through batteries in 3-4 years instead of 8-12 for a volt. Given the high cost of the battery I'd say the protection of liquid cooling is a measurable benefit.

Its also about long-term care and customer perception of reliability. Nissan already had to buy back a number of leafs, lost a lot of respect (partially because of how they handled it, especially compared to how GM handled the battery-fire non-issue). The only friends I had that were considering Leafs are now driving Volts. Designing for reliability, not just minimal cost, is important in a new type of vehicle. Toyota did a good job on that for the Prius which is part of the overall brand reputation. GM is doing the same with the liquid cooling and other reliability design elements in the Volt.

One cannot tell if the Prius PHV's air cooling is sufficient (the design is slightly better than Leafs cooling) but given the battery is sooo much smaller than a leaf its not likely to be an as much of an because people won't really know if its degraded much and the engine turns on a bit sooner since the engine turns on frequently anyhow.

 

Also adds weight on the already very heavy compact.

 

I see the overkill statement was not understood... or intentionally diverted. The discussion is about hybrids, not electric-only vehicles.

Why does a plug-in hybrid that also has a gas engine also need liquid cooling?

The engine can reduce load from the battery-pack significantly. Why put a heavy burden on electric draw during times of heavy demand when it can so easily be prevented by briefly substituting low RPM combustion instead?

It makes no sense carrying around an engine and a transmission to link it if the system goes out if its way to avoid using it. Hybrids achieve efficiency through the sharing of power sources. That lack of balance, depending entirely on electricity, doesn't make any sense.

So what if the engine runs for a few seconds. Does the addition of liquid cooling really justify all that extra expense, weight, and complexity?

 

Sure, reducing fire risk after a collision is good even if the risk was long after the occupants would normally have been extracted, the scenario was specific to a side impact striking a specific location and transmitting the collision energy along a front seat attachment bracket, the car had to rotate upside down even though risk of overturning in the Volt is unusually low due to the low center of gravity, and the damage that induced the fire from the side impact was hard to reproduce so they resorted to simulating the collision damage by damaging the battery pack by itself in a laboratory setting.

The fix was mostly a small piece of additional steel in the battery tunnel to spread the energy from a direct collision impact on that floor seat attachment bracket.

The battery pack automatically disconnects in the event of a serious collision (airbag deployment etc.). It can also be easily disconnected via a plug that is accessible by removing the bottom mat inside the center floor console. Other EVs have similar disconnects. The one for the LEAF is under a carpet flap in the center and just behind the front seats. The real issue with longer term fire risk is not just disconnecting but actual draining of the energy in the pack. That is something that would most likely be done at the junk yard after towing.

Unsurprisingly, you just made this up (apparently without bothering to do a simple 60 second google search). GM was training first responders at least 3 months prior to the first customer delivery.

Here's a quote from a first responder blog back in the fall of 2010.

2011 Chevrolet Volt First Responder Labels | Boron Extrication