In AutoblogGreen Podcast #4
, ABG talked to Dr. Alan Gotcher of Altairnano Technologies
about the battery technology that makes the Phoenix SUT go. You can now read the interview transcript below.
AutoblogGreen: This is Sam Abuelsamid from AutoblogGreen and I'm talking today with Dr. Alan Gotcher who is the CEO of Altair Nanotechnologies. Why don't we start off with just a little bit of background on the company, where you're coming from and what you're working on.
Alan Gotcher: You bet. Altair Nanotechnology is a young company that is publicly traded on the NASDAQ. Our ticker symbol is ALTI. We have just over 90 employees. We're based in Reno, Nevada and we have an operation in Anderson, Indiana that does rapid, product design and rapid prototyping. The company has been developing products for some unmet needs using nano-structured ceramic materials that are providing some performance that really hasn't been achieved before with these materials, primarily because of the high surface area and small particle size that's inherent in nanotechnology. Some people have appreciated the recent advances we've made in battery technology, where we have developed a new class of electrode materials that are used in lithium ion batteries. And it's analogous to what was done with the nickel-based batteries 20 or so years ago when metal hydride electrode materials replaced cadmium in nickel cadmium batteries to produce what's called nickel metal hydride batteries. And we're doing something similar with our nano structure ceramic materials where we produce a lithium titanate material that's used to replace graphite that's conventionally used in conventional lithium ion batteries and as a result we have a new class of batteries that we call nanotitanate to reflect the new electrode material. Now, these batteries have almost unbelievable performance in that they can be recharged very rapidly. Depending upon the power supply, we can recharge these batteries in less than a minute, in large format that would power, say, a full sized all electric vehicle that carries five adults. Those battery packs can be recharged in less than ten minutes. The vehicles are not your conventional, electric vehicles. These are not souped-up golf carts. These vehicles can break loose the tires from a standing start, accelerate to speeds in excess of 100 miles an hour, even though that's higher than the speed limits of American roads. The batteries have tremendous life, estimated to be in the range of 12 to 15 years, or about the design life of the vehicle. And importantly, these batteries can operate at minus 50 Centigrade to plus 75 Centigrade, or 165 Fahrenheit. It's unusual battery technology and the technology's been validated by third parties.
You can find out more about how Altairnano's battery charges so fast, lives so long and their relationship with Phoenix and Zap after the jump.
ABG: Well those NanoSafe batteries, that's the technology that I think most of our readers will be most familiar with. Particularly because of your involvement with Phoenix Motorcars. Can you give us a little bit more of an explanation of the significance of the nano particles and how that contributes to the performance of the battery and the capabilities of the battery.
AG: You bet. Using nano materials means that we're building the primary particle at a very small size, and typically for our material that's at 20 to 30 nanometers. And then we fuse those particles together. And by doing so we get high surface area that's intrinsic to having small particles. And it's the choice of the material, the lithium titanate spinel that gives us the stability and the high surface area gives us kinetics, rapid ability to inject the lithium ions into and out of the crystal structure of the electrode material. So, by having a high surface area we get rapid kinetics, which means we can charge quickly and it also means we can discharge quickly which provides power, which is what allows us to turn the UQM motor on the Phoenix platform and provide 400 foot pounds of torque through the UQM electric drive. That gives us the torque to break loose the tires, it gives us the rapid acceleration and that's due to the small particle size and high surface area of these electrode materials. The long life is due to the inherent stability of the material.
ABG: How does the surface area help, the performance of the battery? What would be the significance of that compared to a typical lithium battery that you would find on the market today?
AG: Well, typical lithium ion batteries that are on the market today would use a graphite or carbon based type electrode. The surface area of those materials are typically around one square meter per gram of material. The materials that Altair produces in its battery typically will have 40 to 200 square meters per gram, so a much higher surface area. A factor of 40 to a couple of hundred times. And it's that significant increase in surface area that gives us the ability to rapidly charge and discharge. Because it's the interface between the surface of the electrode material and the electrolyte that defines, the surface, well, it defines the kinetics.
ABG: What about the battery life? I think I've seen the battery life for the NanoSafe battery is quoted at something like 20,000 charge cycles. That's, as compared to the best lithium ion batteries on the market today being, you know, anywhere from 500 to maybe 1,000 at the high end. How do the nano particles help to achieve that long charge cycle life?
AG: Well, there's a couple of reasons for that. First let's describe what we mean by a charge and discharge cycle for the NanoSafe batteries built on these nanotitanate materials. We'll fully charge the battery to 100 percent state of charge and then we'll discharge it completely to zero percent of state of charge. So these are full charge/discharge cycles, not a light discharge where you just might use 20 or 10 percent of the capacity of the battery. We're using 100 percent, and we also do it very rapidly. Meaning, when we're cycling our batteries, rather than a conventional lithium ion battery which you might charge in say 2 to 4 hours and discharge in 30 minutes, we'll, charge and discharge our batteries in say 6 minutes, which is very rapid. Now, when we do that, you're correct; we'll get 20,000 cycles of charge and discharge, 100 percent charge and 100 percent discharge, and we'll do, 6 minutes to charge it, 6 minutes to discharge it. Now, conventional lithium ion battery's done much slower, typically 2 to 4 hours to charge, say 30 minutes to discharge. Now, there are two reasons for the remarkable stability and the very rapid charge and discharge. It's the surface area of the nano particles that give you the ability to have very rapid kinetics or a very rapid charge and discharge, and it's the choice of the material, the inherent stability of the material that gives you the long cycle life. Now, why is that important? lithium ions are injected in and out of the crystal lattice during charge and discharge. And for our nanotitanate material there is zero deformation. Zero deformation means that there's no swelling or shrinkage when the ion is injected in and out of the crystal lattice. For graphite, it's not a three dimensional host; it's a two dimensional host and it swells and shrinks, roughly 10 percent on a full charge and discharge cycle, as the lithium ions move in and out of the graphite crystal structure. And it's that swelling and shrinkage that causes stress to be built up and concentrated over time that leads to crystal lattice fracture and then that leads to some side reactions that over time build up the internal cadence of the battery which increases the resistance and decreases the life of the battery.
ABG: You mentioned the very fast discharging. Now, I take it that's something you would do in the lab, for purposes of testing the life cycle, or, the life span of the battery. Obviously you wouldn't want to discharge the battery in 6 minutes in a real world application.
AG: Oh, no.
ABG: In a normal type of discharge cycle, do you still get the same kind of performance? The same kind of life span out of the battery? Or would that change?
AG: What typically happens for all batteries and including the Altair NanoSafe battery, the harder you work the battery, the more you exercise it, typically the shorter the life. So if you do 100 percent discharge and 100 percent charge, that's the most severe case. And if you do it aggressively in a short time, that's even more of a worst case. And so if you were, say, to take a battery and charge it over 10 hours and discharge it over 10 hours, that's a very casual, pedestrian charge and discharge rate. And if you only discharged it to 20 percent of its capacity rather than 100, again you're not working the battery very hard. And its cycle life will look better and, so there's curves that you look at. And typically end of life is considered about 80 percent of the original charge capacity of the battery. And as you mentioned earlier, Sam, most lithium ion batteries have an end of life at about 500 to 1,000 cycles if you charge them relatively quickly, meaning 2 hours, and you discharged them relatively quickly, meaning, say, 30 minutes. In the case of our Altair batteries, we're continuing to test what that means. And we're in excess of 25,000 cycles and counting.
ABG: So then in a real world application like for example, in the Phoenix SUT, we could actually expect to see even more than 20,000 charge cycles because most of the time it's probably not going to go through the fast charging and it's certainly not going to go through those kind of fast discharge cycles.
AG: That's correct. And that's why we're confident that the battery life will be in excess of 12 to 15 years. Now, let's talk for a minute about how the battery packs get discharged in use. And so when you stomp on the pedal what you're doing is moving battery power to the UQM motor to the wheels of the vehicle and you're driving the vehicle forward. When you take your foot off you coast and when you step on the brake you actually generate electricity from regenerative braking and you put that power back into the battery pack. Now, the Phoenix sport utility truck carries five full sized adults is specified to have a range of about 135 miles and there's clearly a duty cycle that comes with that, how fast do you accelerate it, what's your top speed, how often do you brake, is it used on the freeway or is it used inside a city. But on average if it's a combination of those, this vehicle typically will have, with a 35 kilowatt hour battery pack, a range of about 135 miles, a top speed in excess of 100 mph, although you probably drive it within the speed limits of the city or on the freeway. And it's got remarkable, efficiency on this regenerative braking.
ABG: What about the currents required to do the kind of fast charging that's been talked about, the 10-minute charges on these batteries? Obviously that's not something that people would be able to do at home. How much current would be required to do a 10-minute charge?
AG: Well, you're right, Sam, there's different charging and recharging conditions. the vehicle has an onboard, converter, so it'll allow you to plug the vehicle into a garage outlet, be it a 110 volt or 240 volt, typically those circuits would be at 15 to maybe 40 amps. When you're rapidly recharging this would be done at a recharge station and the vehicle is designed to be connected to a 480 volt, three phase, 400 amp circuit and it'll recharge in less than 10 minutes.
ABG: What about the energy density of the NanoSafe batteries? How does that compare to some of the other current lithium ion chemistries?
AG: Well, typically we start with, when we talk about the NanoSafe battery, comparing it to battery packs that are used in electric and hybrid electric vehicles today. And the technology of choice at the moment are batteries based on nickel metal hydride chemistry. And with respect to performance on any dimension of energy density, power density, and those really relate to the size of the battery pack for a given application. The Altair technology will be roughly half the size and half the weight of any nickel metal hydride battery pack used today. And it will have typically two to five times the life of a nickel metal hydride battery pack. It's remarkable performance relative to today's battery technology, nickel metal hydride.
ABG: How about in comparison to some of the lithium ion technologies that are being used for some of the upcoming vehicles, for example the Tesla Roadster or some of the things that GM is looking at for some of their future plug in hybrids and for the Volt and for other vehicles.
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AG: Well, let me try to answer that because they're two very different applications. The Tesla Roadster is using laptop batteries. These are cells that are cylindrical that are called 18650 format and they have over 6,800 cells in a battery pack and this battery pack needs to have heating and cooling to keep the 18650 cell in the right temperature range which is typically from about freezing to plus 40 Centigrade. The reason for this is due to safety. At temperatures below freezing, there are issues with lithium metal plating out on the graphite electrode. And above 40 degrees Centigrade, there are issues with and concerns about the lithium ion batteries going into thermal runaway. And the consequence of that, some of us have seen some videos or maybe experienced it firsthand when our laptop burst into flame due to a battery failure. So, Tesla's taking laptop batteries, taking a significant number of them and putting them in serial and parallel so that they can get the pack voltage up about 380 volts and they use a lot of thermal management to manage the safety of those batteries. Now, if you look at the Altairnano NanoSafe battery, our battery technology is inherently more safe and we have a much larger operating temperature window as I mentioned earlier, minus 50 to plus 75 Centigrade, up to 165 Fahrenheit. And so there's no active thermal management. There's no water cooling or using the glycol solutions that might be in a radiator for instance. There's also no heating in our pack, it's all passively managed. So the thermal management's trivial in the Altair battery pack. And, now with respect to power and energy, our power density is about a factor of two higher than conventional lithium ion batteries. And energy density is about 70 percent of a typical lithium ion battery. Now, that's at room temperature. If you drop the temperature or raise the temperature, the Altairnano NanoSafe battery has very little temperature dependence. And so our performance doesn't change very much as the temperature goes up or as the temperature goes down. Whereas there's a strong thermal dependence in conventional lithium ion. And so at low temperatures and at high temperature, Altairnano's power and energy density is actually superior to conventional lithium ion. But at room temperature we do serve and have a penalty in energy density compared to conventional lithium ion.
ABG: Well, I guess even there it's hard to do a direct comparison, because you can vary the power and energy density by varying the chemistry and specific construction of the battery anyway. So, I think it would depend on how you configure it for a particular application. For a pure electric vehicle that would typically be biased more towards energy density rather than power. So it would depend on the specifics. But I just wanted to get a ballpark idea there.
AG: Typically under most test conditions Altairnano's power density will be superior to lithium ion, nickel metal hydride and lead acid and energy density will be superior with respect to lead acid, nickel cadmium, nickel metal hydride, but inferior by about 30 percent, it depends again on the application, but about 30 percent against lithium ion especially in say all electric vehicle applications.
ABG: What about cost wise? How's the cost compare? Obviously right now the ones you're supplying for the initial batch of Phoenix trucks are prototypes so it's not going be directly comparable but how do you see a couple of years from now, how do you see the production cost of the NanoSafe battery compared to what I'll refer to as a conventional lithium ion battery, the type of batteries that other companies are producing right now.
AG: We see ourselves following a very common lithium ion learning curve. If you look at our battery the components that go into it are exactly the same with the exception of our electrode material which replaces the graphite. Other than that, the cell format, the packaging, the electrode materials, the electrolyte and the additives are nearly identical and in the same cost regime. So we see ourselves as we move out of these prototype packs into significant volume that we'll substantially decrease our costs and we expect to be price competitive with lithium ion or nickel metal hydride packs in two to four years. Again, it depends a little bit upon volume and how fast we go through the learning curve. But one way many battery people look at this is to look at it on how many dollars per watt hour of an installed pack does your product cost. And today we're selling our product anywhere from $1.50 to $2.50 per watt hour. And today nickel metal hydride is typically around fifty cents a watt hour and lithium ion is typically today around about $1.00 a watt hour. And we would expect to be below $1.00 in 18 months and below fifty cents in 36 to 40 months. So we'll be very price competitive, over the coming 18 to 36 months as our volume climbs.
ABG: Another thing I'd like to ask you about is the relationship between, Altairnano and Phoenix. I've read in a couple of places that there is an exclusivity agreement between the two companies and possibly some sort of equity arrangement there? The reason I ask is I'm curious as to whether any of that will preclude Altairnano from working with other companies whether other car makers would be able to get your batteries into their products.
AG: Those are good commercial questions. First let me answer that yes, there is some exclusivity agreements in place between Phoenix and Altair. And this is around the use of a battery pack in an all electric vehicle of a certain class having four wheels. And it's limited to North America. So straight out if someone in Europe or Asia wants to access this technology we're open immediately to do that. Secondly, there are many applications that are not all electric. For instance, hybrid electric, plug in and stationary power. And all of those applications are available anywhere in the world. And then finally with respect to the limited range of all electric vehicles in a certain weight class, that agreement is for three years and we are allowed to work with firms but there are restrictions on the quantity that can be shipped near term in the United States. It's a good agreement for Phoenix and Altair. And it gives Phoenix an advantage with their vehicles in the United States and it allows Altair to take our technology into hybrid electric, plug ins, buses, trucks, anywhere in the world.
ABG: Going from there I guess one company that would obviously pop to mind, with respect to Altairnano would be Zap. They recently announced their Zap-X vehicle based on the Lotus APX and the specifications that they quoted for it, based on what they quoted with the fast charging time and the performance capabilities, it would seem that the only battery maker that would currently fit into those specs would be Altairnano. So are you actively working with Zap? Do you expect them to be using your battery in that vehicle?
AG: We have been talking with Zap and Lotus and yes, Zap has, aspirations to use the Altair technology in their vehicle. And we're in discussion around the commercial terms of that agreement. Just a comment if I may, Sam. I'm not aware of anyone who has battery technology similar to Altairnano's NanoSafe battery performance.
ABG: Right. That's why I asked the question the way I did. Essentially your company are the only ones that would fit into the description of what Zap has given for what they expect that vehicle to do.
AG: Well, I'm sure that Steven is, Steven Schneider, the CEO of Zap, he's been quite interested in the Altairnano technology for some time. we've had extensive discussions with Steven and his team and I think he's quite excited about the Altair nanotechnology and what it can do for the Zap vehicle.
ABG: Well, it's definitely very exciting technology, and I'm looking forward to actually seeing it in, in real vehicles in the real world. speaking of which, are you also, working with any other car makers besides Phoenix and potentially Zap, at this point?
AG: Yes, we are. We have several programs, the one that we've talked the most about is our program with Alcoa where we're working on a joint program to provide hybrid electric battery packs that would be used in medium duty hybrid electric trucks. These are parcel delivery trucks and route trucks. We do have some other programs with other automotive OEMs and truck manufacturers, but we've not really disclose those yet, but we'll be saying something about that the second quarter of 2007.
ABG: The last thing I wanted to ask you about was whether there's any current production applications of the NanoSafe battery technology? Does it exist in any applications at all today that people might be aware of?
AG: One that's gotten the most visibility is the Phoenix Motorcars' SUT. We do have a sport utility vehicle that the battery pack is in. And we've also mentioned that we're working on a couple of stationary power supplies and rapid recharge systems. But, at the moment we're just now bringing the product to market and you'll hear more about the commercial applications and product sales of the Altair NanoSafe battery later in 2007.
ABG: Okay. Well, I'm looking forward to that and looking forward to an opportunity to evaluate the real world performance of both your batteries and the Phoenix SUT. Is there anything else that you'd like to share with AutoblogGreen listeners before we finish up?
AG: No, I'd just like to say that Altairnano is moving forward and we're building a great little company and while there's risk at looking at young companies with exciting technology like Altairnano, the reward sometimes is worth the risk and as you watch our technology come to market if you have questions please feel free to reach for Sam or anyone on the Altairnano staff and we'd be happy to try to answer your questions.
ABG: I appreciate your taking the time to talk to me today and, best of luck to you and to your company.
AG: Well, thank you, Sam, and I look forward to talking to you again in the near future.
Previously on AutoblogGreen: