Joined
·
5 Posts
Battery Technology
1 - 20 of 23 Posts
Lithium is an immature technology rampant with risks and uncertainties. Even the basic chemistry is not settled, with Lithium Manganese being the latest more promising combination. So let's be honest; vehicle ready Lithium batteries are 5 years away.
HOWEVER, 10 years ago GM was in production of a car that got 130 to 150 miles on a charge. Since then those NiMH (nickel metal hydride) batteries have powered almost every hybrid made and many have well over 100,000 miles on them in all kinds of climates and driving conditions. Toyota Rav4 EV owners have yet to change out any battery packs and many have over 100,000 miles and that's while driving ONLY ON THE BATTERIES, since the Rav4 EV is not a hybrid.
The concept of a hybrid is to NOT require so much of the batteries, as the generator can keep the batteries at any SOC level it chooses and even assist the batteries when continued high current is called for. So instead of 1000 lbs of NiMH batteries to get 130 miles, the volt could use 300lbs to get it's 40 mile "all-electric" range. This is the right choice for the Volt, and when Lithium is mature, what's the big deal; start putting Lithium in and make it a 100 mile range vehicle without changing much of anything else in the car.
So it makes you wonder; WHY is GM embroiled in hatching a new battery technology when America needs this car NOW, and lots more models like it. Let's get out of the Lithium quicksand and go build this car.
Dr Mark
HOWEVER, 10 years ago GM was in production of a car that got 130 to 150 miles on a charge. Since then those NiMH (nickel metal hydride) batteries have powered almost every hybrid made and many have well over 100,000 miles on them in all kinds of climates and driving conditions. Toyota Rav4 EV owners have yet to change out any battery packs and many have over 100,000 miles and that's while driving ONLY ON THE BATTERIES, since the Rav4 EV is not a hybrid.
The concept of a hybrid is to NOT require so much of the batteries, as the generator can keep the batteries at any SOC level it chooses and even assist the batteries when continued high current is called for. So instead of 1000 lbs of NiMH batteries to get 130 miles, the volt could use 300lbs to get it's 40 mile "all-electric" range. This is the right choice for the Volt, and when Lithium is mature, what's the big deal; start putting Lithium in and make it a 100 mile range vehicle without changing much of anything else in the car.
So it makes you wonder; WHY is GM embroiled in hatching a new battery technology when America needs this car NOW, and lots more models like it. Let's get out of the Lithium quicksand and go build this car.
Dr Mark
Joined
·
4,087 Posts
NiMH batteries are:
1) TOXIC - chock full of Lanthanide series heavy metals (lantanum, cesium, Preseodymium, Neodymium) that leach out of landfills and into our drinking water - it is a clever marketing tool to throw a generic M in the chemical formula to hide the toxicity
2) EXPENSIVE - there is NO path to reducing the cost of these batteries - as you say, they are in thousands of hybrid vehicles, and they are still expensive
3) HEAVY - you can't escape basic chemistry, and the density of the anode and cathode metals in NiMH is 11 - 17 times more dense / heavy than Lithium, so it will never come close to matching the specific energy of the Lithium batteries, greatly reducing weight and size of the battery
Lithium Ion batteries are:
1) NON-TOXIC - it is an organic salt, so it is safe for landfills
2) CHEAP - these batteries are made by the billion for laptop computers, and while formulas may vary, the construction is a well known science
3) LIGHT - the only element with higher specific energy is hydrogen, so it will be the final battery chemistry for mobile applications
NiMH is history for mobile applications, and will only be used in stationary power storage applications around intermittent renewable sources.
LiIon is required for a mass market capable PHEV
"So it makes you wonder; WHY is GM embroiled in hatching a new battery technology when America needs this car NOW, and lots more models like it. Let's get out of the Lithium quicksand and go build this car."
America certainly does need this car NOW.. but to make a difference in CO2 emissions, energy security, trade-deficit reduction..etc.. a PHEV has to have the range, durability, and cost that will enable it to be a mass-market vehicle.
..and to make it mass-market viable, it has to have batteries that have enough energy storage for sufficient range, don't add 1000 lbs to the car, and are durable for 10 years/150k miles..
..and to have batteries with enough energy density/low weight the Volt needs Li-Ion...
LiIon finally has the energy density and other attributes required to make a mass market PHEV possible.
Li-Ion is not a new technology.. consumer electronics, laptop computers, cell phones have been using it for years. Applying it to robust and safe automotive scale applications is the new challenge. It is a considerable (but conquerable) engineering challenge.
If we wanted a Volt that weighed 75% of a Tahoe because of the battery pack, then NiMH might be fine.. but mass reduction is a very significant factor in any vehicle's efficiency.
These GM engineers know what they are doing.. there is no game going on here. Cheer them on for their effort to conquer the first mass scale Li-Ion automotive application.
Once Li-Ion is proven automotive application suitable, a huge number of further improvements in vehicle fuel efficiencies will come to market.. not only in the form of PHEVs, but also the broader use and greater efficiency of mild hybrids and strong hybrid architectures.
"So it makes you wonder; WHY is GM embroiled in hatching a new battery technology when America needs this car NOW, and lots more models like it. Let's get out of the Lithium quicksand and go build this car."
America certainly does need this car NOW.. but to make a difference in CO2 emissions, energy security, trade-deficit reduction..etc.. a PHEV has to have the range, durability, and cost that will enable it to be a mass-market vehicle.
..and to make it mass-market viable, it has to have batteries that have enough energy storage for sufficient range, don't add 1000 lbs to the car, and are durable for 10 years/150k miles..
..and to have batteries with enough energy density/low weight the Volt needs Li-Ion...
LiIon finally has the energy density and other attributes required to make a mass market PHEV possible.
Li-Ion is not a new technology.. consumer electronics, laptop computers, cell phones have been using it for years. Applying it to robust and safe automotive scale applications is the new challenge. It is a considerable (but conquerable) engineering challenge.
If we wanted a Volt that weighed 75% of a Tahoe because of the battery pack, then NiMH might be fine.. but mass reduction is a very significant factor in any vehicle's efficiency.
These GM engineers know what they are doing.. there is no game going on here. Cheer them on for their effort to conquer the first mass scale Li-Ion automotive application.
Once Li-Ion is proven automotive application suitable, a huge number of further improvements in vehicle fuel efficiencies will come to market.. not only in the form of PHEVs, but also the broader use and greater efficiency of mild hybrids and strong hybrid architectures.
Is Lithium an Immature Battery Technology
Dear Jason,
The question was not which technology holds the most promise; the question is which battery is ready TODAY to go into a production vehicle? What we are talking about here is a 316 lb battery pack vs 175 lbs; 140 lbs is no reason to delay production of any and all electric drivetrains.
To date large format lithium batteries are not producable with reasonable yields due to the nanostructure of the plates and the fact that any imperfection will propagate and destroy the cell. That's why Tesla Motors went to production with a battery pack made up of over 6,000 cells. But since they needed the 100+ mile range NiMH was not an attractive option. With a Series Hybrid like the Volt, the big news is that it gets twice the gas mileage of a conventional car and that my friend could cut 150 million gallons per DAY out of the American trade deficit. Driving with zero gas is just a side benefit.
It is pretty well known that Lithium batteries are prone to explosive self-ignition, but their problems with slow deterioration in both hot and cold temperatures is not as well known. Is GM planning to heat this pack every night of the winter for every car in northern climates? Just normal daytime heat in Florida will cause Li batteries (I believe it's true with all Lithium chemistries) to lose 10 to 20% capacity per year (impedance increases). AC Propulsion is very upfront about that and makes their EBox customers sign a paper stating that they realize that a full battery pack replacement within 5 years is a distinct possibility.
The problems you point out with NiMH can all be accomodated, as evidenced by the fact that they are in widespread use in hybrid automobiles. The same cannot be said for Lithium. Case closed.
If you started production of the Volt with NiMH batteries, the Lithium batteries could be made an option when first introduced (assuming that like any embyonic technology, the first production will be low-yield and expensive). Personally I'd like to see a $15,000 version of this car with a 20 mile electric range that uses spiral wound Gel or AGM lead-acid batteries like Odyssey, Optima or Genesis. Then the consumer would really have a choice. Like I said, I recharge my electric car at work, so I only need a 15 mile range to drive 30 miles/day gasoline free.
Dr Mark
Dear Jason,
The question was not which technology holds the most promise; the question is which battery is ready TODAY to go into a production vehicle? What we are talking about here is a 316 lb battery pack vs 175 lbs; 140 lbs is no reason to delay production of any and all electric drivetrains.
To date large format lithium batteries are not producable with reasonable yields due to the nanostructure of the plates and the fact that any imperfection will propagate and destroy the cell. That's why Tesla Motors went to production with a battery pack made up of over 6,000 cells. But since they needed the 100+ mile range NiMH was not an attractive option. With a Series Hybrid like the Volt, the big news is that it gets twice the gas mileage of a conventional car and that my friend could cut 150 million gallons per DAY out of the American trade deficit. Driving with zero gas is just a side benefit.
It is pretty well known that Lithium batteries are prone to explosive self-ignition, but their problems with slow deterioration in both hot and cold temperatures is not as well known. Is GM planning to heat this pack every night of the winter for every car in northern climates? Just normal daytime heat in Florida will cause Li batteries (I believe it's true with all Lithium chemistries) to lose 10 to 20% capacity per year (impedance increases). AC Propulsion is very upfront about that and makes their EBox customers sign a paper stating that they realize that a full battery pack replacement within 5 years is a distinct possibility.
The problems you point out with NiMH can all be accomodated, as evidenced by the fact that they are in widespread use in hybrid automobiles. The same cannot be said for Lithium. Case closed.
If you started production of the Volt with NiMH batteries, the Lithium batteries could be made an option when first introduced (assuming that like any embyonic technology, the first production will be low-yield and expensive). Personally I'd like to see a $15,000 version of this car with a 20 mile electric range that uses spiral wound Gel or AGM lead-acid batteries like Odyssey, Optima or Genesis. Then the consumer would really have a choice. Like I said, I recharge my electric car at work, so I only need a 15 mile range to drive 30 miles/day gasoline free.
Dr Mark
I agree with Dr. Mark in that GM should have made a NiMh and/or AGM EREV vehicle years ago but I don't think those multiple multiple development paths make sense today eventhough an AGM version would be most practical for my use. I don't think Lithium Ion cells kept at 80% or less SOC lose 10-20% per year, even in Florida heat. This sounds like 100% charge decay. Also, I didn't realize LI batteries decayed in cold temps. I thought they just have less power and less working energy.
Can anyone explain why the batteries MUST last 10 years and 150,000 miles?
Can anyone explain why the batteries MUST last 10 years and 150,000 miles?
Joined
·
7,983 Posts
Dr. Mark and Koz
GM wants this car to differ in it's performance in as few ways as possible from that of every other car of it's size. It wants the technology to be as transparent as possible. It also wants to put out a machine that is sufficiently advanced (balanced with good reliability) to reflect the biggest bang for the buck to get the acceptance level up, not just for a relative handful of fanatics (in which I include myself), but also to many, many households worldwide. Anything short of Lithium simply will not accomplish that in Volt 1.0. They've addressed the thermal issued mentioned by Dr. Mark. In fact when I read his first post about the Lion issues, my first thought is that he's got some "old" info on the stability and energy density of SOME of the initial lithium chemistries - not those now available. I believe Dr Weber mentioned sorting through something like 36 "flavors" before looking mostly at these two.
Hope this helps
GM wants this car to differ in it's performance in as few ways as possible from that of every other car of it's size. It wants the technology to be as transparent as possible. It also wants to put out a machine that is sufficiently advanced (balanced with good reliability) to reflect the biggest bang for the buck to get the acceptance level up, not just for a relative handful of fanatics (in which I include myself), but also to many, many households worldwide. Anything short of Lithium simply will not accomplish that in Volt 1.0. They've addressed the thermal issued mentioned by Dr. Mark. In fact when I read his first post about the Lion issues, my first thought is that he's got some "old" info on the stability and energy density of SOME of the initial lithium chemistries - not those now available. I believe Dr Weber mentioned sorting through something like 36 "flavors" before looking mostly at these two.
Hope this helps
Joined
·
3,689 Posts
Folks, Don't overlook the power of marketing. Let's face it, lithium-ion sounds modern (it is used in all the new fancy electronics) and differentiates itself from the old sounding tech. Just the thought of putting lead acid batteries in my Volt makes me cringe.
Joined
·
4,087 Posts
If it were simply a matter of weight, you would be right, but cost is significantly higher and range significantly lower.
Tell that to Lithium Tech Corp., which has been making large format lithium ion batteries for the "military/security, transportation and stationary power markets" for over a dozen years. Their tech was used in the Thunderstruck bike, which holds the world record for 0-60 and 1/4 mile times of any electric vehicle.
http://www.lithiumtech.com/About.html[/quote]
A123 and other Li-Ion battery manufacturers are using a completely different battery chemistry than those used in laptops, for the stated purpose of eliminating thermal runaway conditions. Tesla chose to stick with laptop chemistry batteries, because those are produced in the millions today, so they included thermal management systems and other safety features to eliminate any cascade failures.
How do you accomodate high cost of NiMH? Having taxpayers provide subsidies? Having automakers accept a loss? Having consumers pay higher prices?
You can't make heavy metals non-toxic, so how do you prevent them from ending up in landfills? You end up creating an expensive reclamation program - more cost for the taxpayer, automaker and/or consumer.
As I have refuted your stated weakness of Li Ion, it is your NiMH batteries that are left infeasible.
I've read about lead-acid batteries that use a foam substrate on which to plate a thin layer of lead, reducing weight and increasing surface area of lead on foam matrix to improve overal efficiency, but can't find that website now. I think it may been these guys, but do not know:
http://www.metafoam.com/
Joined
·
12 Posts
Dr. Mark is wrong with all respect
If Chevy wanted to use a Nimh battery the production date would be exactly the same. The Volt is on the standard production schedule. Design-->build manufacturing tools-->test-->sell That's the line.
If Chevy, or any U.S. auto manufacturer wants to make a new product line it takes 3 years. Japanese manufacturers are on a two year schedule.
The battery isn't even slowing down production unless it goes beyond that schedule. The only time it will slow production is at final assembly, if it's not ready in the quantity we need. There's no sign that's the case yet and GM is still in the Design phase.
If Chevy wanted to use a Nimh battery the production date would be exactly the same. The Volt is on the standard production schedule. Design-->build manufacturing tools-->test-->sell That's the line.
If Chevy, or any U.S. auto manufacturer wants to make a new product line it takes 3 years. Japanese manufacturers are on a two year schedule.
The battery isn't even slowing down production unless it goes beyond that schedule. The only time it will slow production is at final assembly, if it's not ready in the quantity we need. There's no sign that's the case yet and GM is still in the Design phase.
Joined
·
1,802 Posts
Okay, I think there are a few points here people haven't considered.
First of all, Jason, thank you for pointing out that the new Lithium batteries are actually "Lithium Iron" and other chemistries, that are different from "Lithium Ion" but we see the names interchanged a lot.
Another issue with NiMh is the owners.. The "good" NiMh chemistry is now owned with a controlling share by the oil companies, who refuse to sell it.
Still, the NiMh batteries used in most hybrids seems to be holding up well enough. I agree - If the delay in the vehicle is simply due to batteries, then use an existing technology - Heck, I don't care if it is lead-acid batteries of some kind. I don't care if that means the range will only be 20 miles. That is still going to cover a lot of people. Heck, my EV only has 20 miles range (with no range-extender to bail me out) and you'd be surprised how many places I can drive it to using no gas at all. I can even make 40 mile round trips if I can recharge at the destination. Only takes my car 3 hours to recharge completely.
So yes.. the battery excuse is a poor excuse. There are plenty of batteries that are viable now. Even the EV-1 had decent range with lead-acid batteries. You can always offer different models with different types of batteries.
Then there is what I consider to be the REAL reason....
GM gave itself a bad name with the EV-1 program. It is trying to dig itself out of the hole. If they come out with a new car using the same batteries the EV-1 used, then suddenly people might ask, "Well, why were all the EV-1's crushed if this technology was good after all?"
So GM gets out of the problem by being able to tout the new Lithium batteries as the reason why this technology is suddenly viable.
Also, the patents aren't owned by oil companies like the NiMh.
One last thing.. I don't think NiMh is that toxic. I think you are thinking of Ni-Cad.
First of all, Jason, thank you for pointing out that the new Lithium batteries are actually "Lithium Iron" and other chemistries, that are different from "Lithium Ion" but we see the names interchanged a lot.
Another issue with NiMh is the owners.. The "good" NiMh chemistry is now owned with a controlling share by the oil companies, who refuse to sell it.
Still, the NiMh batteries used in most hybrids seems to be holding up well enough. I agree - If the delay in the vehicle is simply due to batteries, then use an existing technology - Heck, I don't care if it is lead-acid batteries of some kind. I don't care if that means the range will only be 20 miles. That is still going to cover a lot of people. Heck, my EV only has 20 miles range (with no range-extender to bail me out) and you'd be surprised how many places I can drive it to using no gas at all. I can even make 40 mile round trips if I can recharge at the destination. Only takes my car 3 hours to recharge completely.
So yes.. the battery excuse is a poor excuse. There are plenty of batteries that are viable now. Even the EV-1 had decent range with lead-acid batteries. You can always offer different models with different types of batteries.
Then there is what I consider to be the REAL reason....
GM gave itself a bad name with the EV-1 program. It is trying to dig itself out of the hole. If they come out with a new car using the same batteries the EV-1 used, then suddenly people might ask, "Well, why were all the EV-1's crushed if this technology was good after all?"
So GM gets out of the problem by being able to tout the new Lithium batteries as the reason why this technology is suddenly viable.
Also, the patents aren't owned by oil companies like the NiMh.
One last thing.. I don't think NiMh is that toxic. I think you are thinking of Ni-Cad.
Joined
·
4,087 Posts
I agree the Volt is strategic, but not merely for image purposes. The serial hybrid or E-REV configuration is the path to ZEV's, so it positions GM for the future.
It's not a face saving argument, it is a fact. Li-Ion batteries are a few times lighter per unit of energy, and several times smaller in volume per unit of energy - that makes an enormous difference. Mostly, though, the breakthrough idea of having a range extender, to reduce the total energy storage needed by 80%, on top of the size / weight reduction of going to Li-Ion from NiMH, is what really makes the Chevy Volt economically feasible.
The M in NiMH stands for Lantanum, Cesium, Preseodymium and Neodymium, which are Lanthanide series metals having low to moderate toxicity, so they are certainly not harmless.
Joined
·
1,802 Posts
I disagree. I'm not saying that Lithium isn't better. What I'm saying is that it was still doable with the previous battery technology. The improvements Lithium provides are not an order of magnitude better. And the argument of the range extender doesn't work with me, because GM had a prototype EV-1 that had a range-extender back in the 1990's. So again, this isn't a new idea. If they claim the batteries were too expensive, then they could have easily scaled back the NiMh packs on the EV-1 to a 40-mile (or heck, even a 20 mile) all-electric range, and relied on the range extender for the rest of it.
I still believe that GM knows they screwed up with the EV-1 program, and now they are trying to save face by touting new technology. Yes - the technology for the Volt is undoubtably better, but not a "dealbreaker" better. In other words what they had before was just as viable.
The only difference now is the rising cost of gasoline has made their large Hummers, Suburbans, and Tahoes unattractive and hard to sell. They are feeling the financial pain of their previous strategy. Now they realize they need to diversify their products if they plan to survive well into the 21st century. Now they are sitting there thinking "If only we had mass produced the EV-1, we'd be selling hundreds of thousands of them now with such high gas prices."
Joined
·
7,983 Posts
Adric22
Bob Lutz did a much better job pointing out that GM screwed up back then, in his remarks at the auto show. He knows it. We know it. Get over it.
Is it totally out of the question that they now want to do what's in their stockholder's best interest (even if it involves developing a great vehicle)?
Joined
·
1,802 Posts
Actually. I was unaware that GM admitted to screwing up. This is news to me. Can you point me to some website or video so that I can see exactly what he said? This is interesting, as I was still under the impression that GM had not admitted to anything.
Joined
·
7,983 Posts
At the show, Bob went over the difference between being a car company "with the family name on the building" (read Toyota) and one that is beholden to it's stockholders. When Toyota says "I'd like to sell a hybrid" and the engineers say, but you'll lose money, Toyota can still build it. When GM knew that it'd take 2-300 million to develop a hybrid AND lose hundreds of millions the first few years, Bob said, "Who wants to be the one to present THAT to the board". Maybe someone here knows of a video clip of that part of his presentation, but I know he said it. I was there. He also said that if he had to present the same situation now, the board would tell him to go forward with it.
I think all thefacts are listed here....nimh are older, heavier, and worse for the environment. You get better bang for your buck with Lithium. Will the charging system be able to balance the Lithium batteries. When Lithium batteries are brought down it is best to "balance" the cells within the pack for optimum perfomance.
As well, Lithium batteries can be molded into any shape which makes it easier for a designer (like me) to package it into the space provided.
As well, Lithium batteries can be molded into any shape which makes it easier for a designer (like me) to package it into the space provided.
Bob Lutz Speech at VoltNation
http://gm-volt.com/2008/03/21/volt-nation-video-bob-lutz-answers-questions/
Bob admits in hindsight that GM should have built a hybrid, even though it would have lost money.
He doesn't admit the EV-1 program was a failure, nor should he. It was a major technical advancement for automobiles, and many drivers of the EV-1 raved about it. It just wasn't a commercial success, especially in a era of $1.25 per gallon gasoline.
The battery packs in these automobiles are expensive. If they will not last the lifetime of the vehicle, the owner will be faced with a horrendous replacement cost when they fail. This was a major problem for the EV-1. A significant number of owners would need battery replacement prior to 10 years, and this would give the EV-1 a bad reputation. See the following link for more discussion:
http://www.treehugger.com/files/2006/07/ev1_criticism.php
I expect the Volt to actually be an updated, more advanced version of the EV-1. GM was onto something great with the EV-1, they just couldn't make a good case for the batteries. With Li-Ion and a range extending ICE, they are poised to manufacture a world-class vehicle that has no compromises.
See this post on the GM-Volt website, link attached.
http://gm-volt.com/2008/03/21/volt-nation-video-bob-lutz-answers-questions/
Bob admits in hindsight that GM should have built a hybrid, even though it would have lost money.
He doesn't admit the EV-1 program was a failure, nor should he. It was a major technical advancement for automobiles, and many drivers of the EV-1 raved about it. It just wasn't a commercial success, especially in a era of $1.25 per gallon gasoline.
The battery packs in these automobiles are expensive. If they will not last the lifetime of the vehicle, the owner will be faced with a horrendous replacement cost when they fail. This was a major problem for the EV-1. A significant number of owners would need battery replacement prior to 10 years, and this would give the EV-1 a bad reputation. See the following link for more discussion:
http://www.treehugger.com/files/2006/07/ev1_criticism.php
I expect the Volt to actually be an updated, more advanced version of the EV-1. GM was onto something great with the EV-1, they just couldn't make a good case for the batteries. With Li-Ion and a range extending ICE, they are poised to manufacture a world-class vehicle that has no compromises.
1 - 20 of 23 Posts
