Volt or Leaf?

Today I Googled "EV1" and read several most interesting articles about the GM EV1. Facts that I did not recall and never remember reading. Anyone interested in EV's should go back and read some of the history of these fascinating vehicles.

 

You can learn a lot about the EV1 if you checkout Darrells page on the EV1, he "owned" one (well, leased, since they where all leased)

Darell's Electric Vehicle Page

 

More reason to think LEAF.

 

i dont blame you. when i remember even half the events surrounding the EV 1 i go into a deep state of depression.

so on the one hand, its good to remember what we did in hopes that the debacle can be avoided

on the other hand... forgot what i was gonna say, i am now depressed

 

Having read about EV1 .... I wonder why GM only claims a 40 mile range? From other post, we have seen the Volt's battery ... it is enormous, a large "T" shaped device that limits the Volt's capacity to 4 occupants. Plus, it is touted to be the latest in battery technology. Then why only 40 miles? The EV1 had further range on very "primitive" batteries, although they were enormous as well.

Someone suggested a while back the Toyota's "genius" was energy management, explaining the Prius was really remarkable in all that it accomplished with a very small battery. Maybe GM's "energy management" is not as refined?

 

GM is being cautious with the Volt and only using 50% of the battery (its a 16 kWhr pack as I understand it and it's limited to ~8 kWhr). They probably could get 80% usage of the battery and be fine, but since the chemistry is still relatively young they want to make sure it lasts the full 150,000 miles or whatever they're warrantying it for.

The old chemistry for the EV1 was NiMH which was /very/ heavy (weighing ~1000 pounds). The new Lithium pack weighs ~400 pounds and is much more resilient in colder climates. I think the EV1 also had a "lead acid" option for a lower-end system and that battery weighed 1,400+ pounds...

The LEAF is using the same battery chemistry (24 kWhr), but they're using 80% usage, hence the much larger range.

Andrew

 

GM wanted the EV1 to fail from the start because they didn't want to build cars that didn't burn gasoline. Their ad campaign was basically to say, "This is a lousy car; go out and get one." Then they didn't sell them, only leased, and finally took them all back and crushed them: perfectly good cars!

The lesson they learned is that people WANT an electric car with over a 100-mile range, so they're building the Volt to only go 30 miles (claimed 40, but we know what their claims are worth) in hopes that that, along with the $40,000 price tag, will discourage people from buying them.

Are you sure? I was under the impression that Nissan is using a proprietary chemistry, developed in-house, or with a partner.

 

Fairly sure--yes. Everybody has their own proprietary method for making batteries but the core chemistry is essentially the same. Most of the "proprietary" business has to do with how the cells are packaged / produced. I believe it's a newer method for constructing the cathode that apparently is easier to manufacture (hence, cheaper).

Andrew

 

I hate to agree with daniel but nissan is using Li-maganese, other chemistries I've seen is Li-cobalt, LI-lead. Nissan is the only one using LI-maganese combo I know of.

 

I'm pretty sure the volt was originally planning on using a LiFePO4 chemistry (eyeing A123 as a possible supplier) but I believe they switched to a Li-manganese chemistry to cut costs (remember the announcement a few months ago about how they suddenly expected the battery to cost a lot less than previously calculated?).

I could be wrong about this, they obviously haven't published official detailed specs on the batteries--it's more from extrapolations on news articles about the battery and claims from volt engineers. We'll know for sure once more details come out I guess.

At any rate, my original comments about the volt battery usage and how it compares to EV1 still apply since it is clearly a lithium ion format of some variety .

Andrew

 

The battery chemistry of an EV and and ER-EV are very different. I am pretty sure that the battery has to be denser (which brings up more thermo derived issues).


Elon Musk explained it better than I ever could, some of what he says is fud, but take to heart when he talks specifically about the battery chemistry.

You are correct that some inherent drawbacks from using anything LI based. If Nissan can negate the drawbacks with the LI-Maganese
chemistry, they will be top dog in the low-mid priced EV market.

 

I vote for the Leaf. I can't wait to buy one. For me the full EV makes great sense. We use the Prius for road trips, and use the Leaf around town. Plus with all the great rebates, we got solar panels installed this year. Charge the Leaf from solar power. Sounds like a great solution to me!

 

There is absolutely no inherent reason whatsoever why a BEV and a range-extended EV must use different battery chemistries. It is likely that GM and Nissan will end up using different kinds of batteries because they are different companies using different suppliers or developing different technologies in-house. But both cars need to store electrical energy, and both benefit from reduced weight, increased energy density, and reduced cost. Both cars need a battery that can supply sufficient power to the motor, and while the Leaf will go farther, that just means it needs more battery.

Both could work perfectly well on identical chemistry, and if it's the best chemistry available, they would be smart to do so.

 

I am out of my league discussing electrical matters.

That said, having read of the extended charge time with 110v house current, although shorter charge time with 220v ..... will it not require an enormous solar array to provide sufficient power to charge an EV battery?

Also, you will be religated to charging the EV during the day time.

I have had some experience with hot-water collectors, and I have been impressed, but photovoltaic collectors have (in the past) not provided much electricity .... maybe newer models do?

Do you have a "tracking" system that follows the suns path and maximizes output?

Good luck.

 

What generally happens is the solar array charges a battery bank, and the battery bank powers all demands the house outlets need until it dies, and then it switches over to the grid. So you may technically be charging off the grid at night, but you are powering your house in the day from the solar bank primarily. Alternatively, you can have a secondary battery bank just for the EV, but it seems silly just to say with 100% certainty you are powering it via solar. 20% solar is better than none.

 

In addition, it depends what you mean by 'enormous'.
Our 9.6Kw array (about 44 panels) makes, on a good day in March, about 50 Kwh. Much more than a single day's charge for an EV.
Our system is grid tied, so we pump energy into the grid during a bright day when we are making more power than using. And draw from the grid when using power at night, or on a cloudy day if we aren't making enough.
So technically a system like this isn't powering the EV directly, but if the express purpose is to power an EV and the solar array generates more power over time than the car uses over time...

 

Zythryn, you must have an enormous house, I just got a quote on a system, 24 panels, 5.50KW, costs about $37K, then there is the %30 Federal Tax credit and a $1K MA State credit, along with a Mass Solar rebate of $1/watt (another $5K off), still the payback is about 10 years. Not sure I am going to do it, as I don't think I will be in this house for another 10 years... FYI, my southern exposure only had room for 24 panels.

 

Big, but not huge. We cheated a bit. The peak between the side and back of our house faces due south. So our back is facing SE and the side faces SW. So we used the real estate on both sides.