Taking batteries from the lab to the sky in the aerospace industry – The Battery Podcast S02E01 – Transcript
Aerospace is not an industry we talk about in the battery industry, but it offers a very interesting dynamic when designing cells, packs, and integrated systems for flight applications. Listen to part one of our conversation with the VP of Aerospace and Defense and find the whole transcript below.
Nick Finberg
Welcome to Season two of the Battery Podcast from Siemens Digital Industries. I’m you moderator Nick Finberg and I’m joined by our resident host Puneet Sinha, the global head of battery industry at Siemens Digital Industry Software. And we’re here to bring you great conversations from industry experts from across the battery landscape. To kick off the new season, we have Todd Tuthill the vice president of aerospace, defense, and marine industries at Siemens Digital Industries Software, for a conversation around the battery integrations taking flight in aerospace.
Puneet, you were the one that kind of pushed to have this conversation on Aerospace, why don’t you start us off?
Puneet Sinha
I first want to share my excitement to be on this podcast with Todd, not only because he’s a great person and it’s always fun to be on a podcast with him, is also because whenever we think of electrification of transportation system, most of the time the conversation goes to electric vehicles, four wheelers, two wheelers, or the big vehicles, off road, on road. But there is this whole dimension of air transportation, and that is, in a way, a key area where industry wants to take electrification to. And that is, in certain ways, really tough. So when we look at it from the battery’s perspective for many, many years, we always have looked at what will it take to bring electrification to air transportation. And as Todd said, air transportation comes in different flavors. Electric VTOL, air taxis that Todd talks about is a really exciting area where we are seeing the first wave of how batteries can be part of air transportation. But that is just starting point. There are many, many different dimensions. Todd mentioned drones. Of course, in the longer time horizon, there are ambitions of what will it take to electrify short to mid-range air transportation. And of course, the transatlantic, trans-ocean is perhaps far away, but it’s still on that journey. So when we look at this framework, it’s not good enough to look at those systems only from batteries perspective, but also from the perspective of what Todd brings, a seasoned leader in the aerospace system. And I’m glad that our audience today is going to listen to Todd, a seasoned aerospace leader, who can share when he looks at system and battery being a part of that, what are the requirements, what in aerospace industry is looking for to bring batteries and other electrification technologies in those systems. So to me, that is key highlight of this podcast to be listening and sharing and exchanging views with Todd.
Nick Finberg
What innovative things are happening in the aerospace industry for electric aviation and the role in battery supporting it? Todd, what are you seeing in the aerospace?
Todd Tuthill
There’s all kinds of incredible things going on in aerospace. I’ll talk about two. I’ll talk about point-to-point cargo and delivery, and George Jetson’s car will be the second thing I’ll talk about. So let’s talk about point-to-point delivery. Cargo. We’ve kind of all seen the commercials, you know, about these small drones delivering Amazon boxes and pizzas, and that is kind of taken off. But there’s one company in particular that I want to call out. They’re called Zipline Aero. And all the listeners, if you’ve never heard of Zipline, you got my permission, pause the recording, go look them up. Zipline Logistics. They are an incredible company now, flying small electric drones. And they’ve, since 2016, they’ve done more than a million deliveries, flown more than 90 million miles, mostly in Africa. And their website says they’ve already sent things to more than 4,000 hospitals and health centers in Africa. And they’ve saved a lot of people’s lives with these small electric drones that fly there and back. So point-to-point delivery is the thing. We don’t see it as much in this country, but in emerging countries like Africa, where it’s hard to get things places, we’re starting to see those drones, really make an impact. So in addition to point to point cargo delivery, we’ve also got flying cars. When I was growing up, I’ll date myself, one of the cartoons I loved to watch was George Jetson. And the cool thing about George Jetson, he didn’t take a car to work. He and his family took a flying car. It wasn’t a car that went along the road. It flew through the air. And I always wondered, would that ever happen in my lifetime? And the cool part is it’s going to happen in our lifetimes. It’s going to happen by 2030. Puneet and I, we’re going to fly together on one of these air taxis between now and 2030. And there are a number of companies working on that. They haven’t been certified yet. But by the year 2030, you’re going to go to a large city, and if you want to fly from point to point, to avoid traffic, if you’re in LA and you land at LAX and you want to get to the beach in South Beach without a two-hour wait in traffic, you’re going to be able to fly there in this air taxi. And just such cool things, such a cool time that we live. And I can’t wait to really get into this with Puneet in this podcast and talk about all the challenges and all the cool things that lay ahead with electrified air transport.
Nick Finberg
I’m curious, Puneet, what’s happening on the battery side to kind of help feed into aerospace? Are you working directly with any of the OEMs for designs? Or is it just kind of they’re taking stuff off the shelf?
Puneet Sinha
So answer is yes, we are starting to work with some of the companies exactly on the lines of what Todd said. In the air taxi domain, there are a lot of companies, some of the ones that people are more aware of, Joby Air, Lillian, there are many such companies. There are many companies who are actively working in that domain. We are looking to work with them to see what are their challenges, how those challenges are different from ground transportation, and what does that mean for batteries requirement, both for design, but also safety side, also from the usage profile and durability. And all those dimensions I look forward to covering in this podcast with you and Todd.
Nick Finberg
Well, let’s kick it off with one of those challenges Todd mentioned. Storage density is a big problem across battery applications. It’s going to be especially so for aerospace. Every kilogram we can remove is extra distance you can fly. How is that shifting the communication between aerospace OEMs and manufacturers?
Puneet Sinha
Great question, Nick. As I mentioned earlier, all the batteries that we have designed, we means as in, battery industry has been designing and manufacturing. Predominantly looking at vehicle electrification in mind has been, and increasingly for battery energy storage systems. So, either a stationary application or ground transportation. And roughly, the state of the art battery energy density is close to somewhere between 250 to 300 watt hour per kg. What does that mean is one kg of lithium ion battery cell today carries around 300 watt-hour worth of energy. That is a significant improvement in the energy density in last 10 to 15 years. It has almost tripled. And that is because of all the material level breakthroughs, improvement at the cell and pack level in the design and engineering and how they are being manufactured. As great a breakthrough and advancement it has been, that number is still falling significantly short when you start looking at air transportation. The magic number in certain way that unlocks a mainstream conversation for battery power air transportation is 500 watt hour per kg. So if you look at it, almost 80% additional improvement in the energy density is a significant improvement is required, desired to make air transportation powered by battery mainstream. And this is where the great challenge lies for the battery industry to increase that energy density through material innovation, through improvement in design, while making sure that those batteries are absolutely safe. Because we cannot emphasize how critical it is to have those batteries safer for air transportation. Todd, how do you see it?
Todd Tuthill
Yeah, I think you’re exactly right, Puneet. That magic number of 500 is certainly true in terms of profitability. And if you think about the impact that has on not just the design of the aircraft, but the whole concept of profitability for this industry. If I look at most of, we talked about air taxis, which is probably where we’ll focus a lot of our discussion today. Most air taxis today, if you look at the weight ratio and the size, you put it all together, they’ve got a range of about 80 to 100 miles. That’s maximum range. And that’s on a that’s on a good day with good weather. When you factor in bad weather and margins, it may even be a little shorter than that. So most of the industry right now in the air taxi market is being designed around that number, 80 to 100 miles, with the reality of really, most of it will be point to point within large cities. That’s where we’re going to start. And it’s going to take a whole lot of aircraft and a whole lot of passengers to make that profitable. When it really starts to become more profitable and i think that 8200 is really based on from what i’m told current day technology you know the 250 to 300 number uh when we start getting up to the 200 250 mile range now we can start talking about flying between cities not just inside of a city but from city to city and that’s where we’ll start to see more and more profitability because really if you think about now an air taxi they’re competing with uber and their you know their business model is we’re going to get you faster we’re going to make you faster across a large city to not wait in traffic and while there is certainly some utility in that when it really starts to become a bit more profitable will be when we can build a little larger versions of these vehicles that can hold more than four passengers that can hold six or eight or ten and i can fly between cities and then we’re talking about more profitability and it’s going to take that 500 to 600 kilowatt hour battery to get there or did you say what hour kilowatt hour i think i got the units wrong but i think you know you know what i meant yeah twice twice twice where we’re at today yeah and and the other question i think uh you asked was how does that affect the communications of oems and battery manufacturers and what i’m seeing in aerospace because this is such a critical thing in some cases they’re one in the same some of these oems are actually getting into the battery technology i’ve talked to some of the oems i won’t name them but some of them ask them about the batteries and they’re saying which batteries you’re using and they’re saying well our battery technology is proprietary and they’re having to really invest a lot of time and money to develop this proprietary battery technology of their own just so they can get a leg up on their competitors so it’s uh it’s a big big deal and well i’m sure we’ll talk more about what that means relative to this industry and the decision to go into it and the ability to prove that you’re profitable to your to your venture capitalists investing in your company
Nick Finberg
um you said climate and kind of the environment that you’re going to be flying a route for for one of these air taxis has a big impact on range I’m curious if on a cold morning i have to make sure that my ev is plugged in to get a better charge for commuting um are there steps that you kind of have to take for these kind of aircraft? are we to that point where we’re thinking about that infrastructure um for the battery systems
Todd Tuthill
absolutely uh you know if i think about uh again an air taxi i think there’s a couple of options uh one option would be you’re going to warm the battery with it still plugged in which of course takes time a way that you’re not making fine revenue flights there are also some companies that are designing their air taxis with removable batteries where they’re not actually going to charge them when they land but they’re going to swap out a new battery pack and therefore the battery pack would go in warm now another thing to think about it’s not a apples to apples comparison of an air taxi to a commercial aircraft because part of the reason commercial aircraft have to de-ice so often is they’re not they’re flying at 35 000 feet where it’s minus 40 degrees outside most of these air taxis are going to fly at 4 000 feet not not 35 000 feet where it’s still cold where it’s still cold uh in a lot of places and especially in places like the northeast in the winter but it’s not going to be minus 40. so it’s a little different but still that’s certainly a concern uh that batteries have to stay
Nick Finberg
so it’s less about the the exact flight safety requirements versus range implications
Todd Tuthill
there’s there’s that too we’ll probably get the flight safety uh but it’s uh it’s not quite like flying at 35 000 if you had to fly if you had to fly a battery-powered aircraft at 35 and 40 000 feet then it becomes a big big deal to keep those batteries warm and uh it’s not going to be quite that cold at 4 000 feet in in most places unless this we’re going to fly in anchorage or something i don’t think we’re we’re ready to put our taxis in anchorage alaska yet
Nick Finberg
okay um so lifespan and longevity is another topic i’d like to hear from both of you about um what is the average average operating life of of these aircraft um and will batteries be able to maintain the charge discharge cycles of of commercial applications or are companies looking more into to repairability um rather than durability
Todd Tuthill
yeah so you you want to give you a scope okay so we’ll go back to the question so think about time frame for the life cycle of these aircraft so let’s talk about a typical commercial aircraft you’re talking about a lifespan of 20 to 30 years i i don’t know that we’ll see that out of these initial air taxis necessarily maybe it’ll be closer to the lifespan of a car but that’s probably at least 10 years so you’re looking at anywhere from 10 to 30 years lifespan on on these aircraft and they’re going to fly seven days a week they’re going to fly from dawn till dusk probably even after dark they may fly 8 10 12 15 times a day so you’re talking about many many thousands thousands of cycles and certainly uh longevity of those batteries is a very big concern because when when you think about the the statistics we’re quoting before about 80 to 100 miles that’s assuming a battery that’s that’s got most of its life left and again i think about my cell phone and what i’m what happens to my cell phone after a couple of years all of a sudden my cell phone that went two days on a charge now i’m i’m wondering if it’s going to make it to the end of the day and that’s uh that’s not going to be acceptable for these air taxis to to have the the range and the safety they need they’re going to need to have 80% plus of the battery life so i i think what that’s probably going to mean relative to uh to these aircraft uh is that uh they’re gonna have to price into the life cycle cost of the aircraft replacing the batteries a number of times unless Puneet’s going to tell me about some magic technology here that i don’t know about yet that’s going to suddenly make these batteries have a much longer life i think that’s just going to be part of of these uh these first wave of designs that they’re going to have multiple sets of batteries over their lifetime
Puneet Sinha
yeah Todd, i don’t know any such magic but i i second you so if you look back what defines or determines life of a battery from a very first principle basis there are two key things that are critical to determine the life of a battery in whichever application you use whether it’s a cell phone a car or or a air taxi what is the temperature what is the temperature batteries are exposed to and second is cycle how you’re cycling the battery you know what is the maximum voltage you are taking to minimum voltage you’re taking to and how many times you’re going through so it’s essentially it comes down to in the battery language cycling of battery which voltage range you’re taking to and the other is when you are not using battery what are you doing with it is it all the time plugged in is it exposed to high temperatures which can have some adverse effect and those first principles or the the basic physics or electrochemistry applies to batteries that will go in air taxi systems and so on and so forth so let’s look at it as as todd said if you look at evtol when they are operating they are at higher higher altitude lower and that means lower ambient temperature than what a typical car typically get exposed to typical electric vehicle in an electric vehicle you have to cool the battery down a lot more than you have to heat it up right i mean of course in the winters and if you’re in a very cold place you will have to heat a battery so you have to heat it up and you have to cool the battery but most of the time it is about how you’re going to cool the battery so that its temperature remains in a favorable zone for a battery which is somewhere between 10 degrees celsius to 35 degrees that’s exactly the temperature range of a human but what keeps a human happy and efficient that is one and you know of course how evtol is getting operated those temperature ranges that evtol exposed to is going to be different it will have implications on how to cool or heat up a battery in a evtol that will determine its life second thing is the kind of duty profiles a battery will get exposed to an evtol is absolutely going to be very different than the kind of duty profiles a typical electric vehicle get exposed to one of the and the way i’ve understood there are two three key things for evtol one is when it lift off and lift off that requires a lot of power much higher power um than what what is required in an electric vehicle then when it is cruising then it’s a lot lower current you’re drawing but then when you’re landing again you need to have a lot of power and there are certain faa regulation that starts coming in on how much charge you need to have before you can land um an evtol so that means it’s a much higher power requirement for a short period of time both when you are going up in there or when you’re descending and much higher temperature and one of the very important thing is there is no regenerative braking in electric vehicle you need to account for when you’re doing braking battery should be able to accept that charge and that has that that starts determining how much of battery power or how much of battery voltage you can use in evtol you don’t have to worry about regenerative braking so that changes the operating window for a battery in a evtol compared to electric vehicle so all of these boundary conditions it starts impacting the voltage range battery in evtol will be exposed to or should be exposed to is thermal management and the ambient conditions it will be it needs to operate in so to ensure safety as well as longevity it comes back to again the materials chemistry that can withhold those voltages and temperatures but also at a system level how a battery is being managed thermally through its thermal management strategy and also how every cell is being managed in a way that is safe and reliable and that is being monitored and state of health is being monitored through its battery management system those fundamental things that are very critical for a success of battery in electric vehicle or an energy storage system applies to battery in evtol it’s just the boundary conditions are different
Todd Tuthill
and nick if i could follow up and build on what uh puneet says because if you think about all those things nick uh that Puneet talked about relative to the what are the what effects of battery and then you look at the financial model of a of an air taxi and compare that to the financial model of of operating an e-v-tol car the reality is most people that drive a an electric car own the car and it spends most of its life parked somewhere where it can charge for a long period of time then it operates and you you go to your office you park it all day you park in your garage because you own it no one else is driving it that’s not the case for an air taxi when they’re first released i think i don’t know five years ten years it’ll be a long time before most of us can afford to own or own their taxi we’re going to rent them we’re going to rent time in them like we rent time in a taxi cab or pay a fare to ride a bus or a commercial aircraft which means those things are operating all the time which which means they’re either operating or they’re charging and Puneet said something really key he said it’s it’s also the temperature that the battery is when you charge it well if you think about the use case for an air taxi we’ve created uh you know kind of the perfect storm i’ve just landed which is you know takes the most power required uh the whole uh flight of that aircraft just about is landing it uh so the batteries pumped out all this power has gotten really hot i’ve unloaded the passengers and i want to very quickly recharge so again unless we come up with some new laws of physics or some other way these batteries are going to be charged hot which is going to reduce the lifespan of these batteries which again is going to make them not nearly as useful for air taxis so it’s a it’s a perfect storm it creates some some interesting engineering uh problems that companies have to overcome and you know again which is i think why we’re seeing some of the uh the oems decide to to not charge the batteries inside but to swap the batteries out because if you can do that you can start to well it’s a bit more expensive because you have multiple battery packs you have to be able to charge the batteries inside and you have to be able to charge the batteries out and you have to be able to charge the batteries out and you have to be able to charge the batteries out and you have to be able to charge the batteries out and you have to be able to do the fast charge when hot which will certainly increase the lifespan of the batteries it’ll be interesting to see i i haven’t seen the trade studies to see what’s actually cheaper just to run the batteries hot all the time and replace them all often and not have to have you know with a custom designed in the vehicle or to add the extra weight and complexity to swap them out every time and and i suspect we’ll see that change over time as a as battery technology and air taxi technology evolves
Puneet Sinha
one thing i also would like to add because todd said it a couple of times and he’s absolutely right that it’s not companies are looking at evtol and batteries and they’re not just the technology but how it needs to be operated which is different than our our personal own electric vehicles right they are they are not going to be idle most of the time most of the time they are working so you know we’re not going to be able to do that we’re going to be able to do that we’re going to if you look at it in our previous episode we have talked about buses we have talked about that battery swapping we have talked about cell to pack technology all of those dimensions get activated in this perfect storm of evtol as todd said it because as he said i mean the if you look at it battery swapping is getting a new life again in china there is a lot of activities happening on battery swapping even for electric passenger electric cars instead of charging them when you look at evtol perhaps there is a very different business case of why to do that rather than charging right um as as todd said charging a battery hard while it is hot he just landed you have to charge and be ready for another flight so if you charge it you have to cool the battery while you are charging and you have to dump a lot of power in the battery to charge it quickly because every minute evtol is charging it’s not making money for the operator so does that open up new business cases and justification to swap the battery those are the things i know companies are looking at but then it is not just about hey i’m going to swap a battery if companies are looking to swap batteries how you put those batteries what kind of modularity you need to have in the battery centralization the form form in a form factor where they are put it in an evtol you know ease of removing those batteries all of those things needs to be accounted for when the batteries are being designed and how the whole system is being designed so all of this companies need to look in from the very beginning these are not something that companies may want to look at in an afterthought process and that starts adding to the complexity
Nick Finberg
That seems like a good place to stop this episode, but we still have more to talk about with Todd on the aerospace industry. Make sure to subscribe so you don’t miss part two of our discussion where we cover some of the design implications regarding safety and what the future of electrification in aerospace could become. Until then, you can check out our previous episodes of the podcast, with customers and industry influencers. Or read into our solutions on our website siemens.com/battery.
