Episode 7: Sophie Lee on Batteries, Chemical Energy, and the Future

Illustration of an Na-ion battery.

Image: Illustration of a Na-Ion battery system. (Source: Wikimedia Commons)

Our latest episode is available from our podcast host here: Episode 7

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One topic we touch on briefly is the inequitable distribution of energy and the placement of energy production plants to serve some people over others. One article Sophie recommends on the subject is here: “This prof is shedding light on energy injustice — and how to fix it”

Transcript available below the read more.


Charles: This is Assigned Scientist at Bachelor’s, I’m Charles and I’m an entomologist.

Tessa: And I’m Tessa and I’m an astrobiologist.

Charles: And today we have another guest, Sophie Lee. Hi Sophie.

Sophie: Hi,

Charles: Can you tell us about your background in science and your interest in science?

Sophie: Yes. So I am a chemical engineer and more specifically, a electro chemist or a battery research scientist. I am currently doing my PhD, and before that I worked at a startup developing, sort of, batteries for grid scale, energy storage. Got interested in science at a really young age, actually originally wanted to be an astrobiologist, but could not do biochemistry to save my life and got really interested in renewable energy in high school, and so switched over to electro-chemistry

Tessa: Well, it’s not astrobiology, but it is, I believe, a worthy cause. So I forgive you.

Sophie: Yeah,

Charles: Well you are our first non-biologist, so. Congrats, I guess.

Sophie: I mean, yeah. So I study how to make batteries last longer and why batteries fail.  The reason I do this is because as we move towards wind and solar energy, we need a ways to store that energy because the sun isn’t always shining and the wind isn’t always blowing and the tidal waves aren’t always flowing in the ways we want, and so long term energy storage is really key to a renewable energy future.

Charles: Could you explain how batteries store energy to me as if I were like a precocious ten-year-old?

Sophie: So right. Batteries are a form of chemical energy storage. So basically they store energy in terms of chemical potential, which is perhaps above a 10 year old.

Charles: So, well, I am a… precocious, precocious ten year old.

Sophie:  One way to think of it sort of is like hydro is not a battery, but it’s another form of energy storage. So if you move water uphill and then let it flow downhill, you can capture energy from that. So batteries do that by pumping electrons up the Hill and then letting them flow downhill and getting energy.

Charles: I have an extremely basic question. What on a physical level is energy? Like, what are we talking about when we say generating energy or storing energy,

Sophie: The power it takes to do stuff? I don’t know. Um…

Charles: Because, okay. So as a biologist, the things that I study, I have a very clear physicality, like an insect. I can hold it and I can look at it. And I can, you know, whisper at it how cute it is, you know, it’s a very immediate physical object.

Sophie: So like energy is the ability to do work and work is like defined as like the ability to like, you know, it’s to create change sort of in the environments

Charles: So energy is like less of a physical thing and more of a description of potentiality?

Sophie: Right –  well, energy in terms of physics is the ability to perform work. So like, energy is the power that enables like molecules to move.

Charles: So let’s say you have like a wind turbine, like connected to a battery. How is it that the wind turbines spinning then gets translated into like that stored energy?

Sophie: So, right. The wind turbine spinning moves a magnet through a coil and generates that creates then electrons that flow through a circuit.

And then those electrons can go to your house and power your lights. Or they can go into the battery and force a sort of chemical reaction to happen. That’s like storage in bonds and molecules moving from one place to another place. And then when you want to get those electrons back out, you break those bonds or you move those molecules back down the chain, and then you can turn on the lights in your house.

Charles: Fantastic. I do realize I was just sort of asking you to explain the fundamentals of electricity and I think you did great.

Tessa: So my master’s degree was in environmental science. So obviously I got to learn a lot about sustainable and renewable energy sources. I understand that with batteries, and this isn’t as much of a problem for grid scale, I think as much as it is for like car batteries for electrical cars or whatever, but were are you trying to focus more on like higher energy density? You know, being able to store more electricity in a chemical form per cubic area or were you mostly focused on, you know, being able to put that energy back in, discharge it and repeat over and over again without degrading your battery?

Sophie: Durability is really important with grid scale because you have all this other sort of hardware that’s going along with like, uh, Grid scale application, the size isn’t quite as important. When you think about like your watch or your car or your computer, you want those to be really small and really light. And that’s less important when you’re talking about grid scale, you know, it can’t be too big, but there is a little bit more tolerance. So. Um, some of my research focuses on sodium batteries, um, sodium’s one below lithium on the periodic table.

Tessa: I was actually gonna ask what electrolyte you were working on. Yeah.

Sophie: Yeah. So sodium is similar to lithium in a lot of ways, but it’s larger, and it’s also really, really abundant and really, really cheap as opposed to lithium, which is more scarce, more expensive, and also more isolated in terms of where it’s spread out across the world.

Um, so then there becomes issues with mining lithium, also lithium batteries use cobalt and mining that also has implications.

Tessa: What are you specifically hoping to get out of your dissertation research? You know, what is sort of the engineering goal of, you know, making a better battery?

Sophie: Originally, I was hoping that I could engineer the surface of the negative electrode, which is a carbon material, to allow it to last longer.

So in both lithium and sodium batteries, the electrolyte will always undergo degradation as a function of… it’s not corrosion, but it’s similar to corrosion. So the way I would explain it to a non-expert is like, if you think about, like, copper oxidizes in air, and that’s why the statue of Liberty is green and not a nice copper color.

But it also then will stop. So once you form a certain amount of time oxide layer on the surface, it doesn’t keep degrading. That’s why the statue of Liberty hasn’t crumbled and fallen apart. So you want the same thing to happen in batteries. There’s going to be reaction with the environment at that interface, but if that reaction is self-limiting, it’ll allow the battery to keep operating without continuing to break down, but in sodium batteries, that degradation keeps happening. And so I was originally trying to engineer the surface to prevent that and sort of moved into developing tools to study that degradation process.

Tessa: Cool, cool. So actually that was the other thing I was wondering is what sort of like tools and techniques do you use to study? I mean, is this like, are we talking about… in my world in astrobiology, you know, it’s all about mass spec and Raman spectroscopy. So I was wondering which, basically, ways of identifying molecules by how heavy they are or what sort of light they give off… I have no idea. What sort of thing you use in sort of like the electrochemical engineering world.

Sophie: Yes. A lot, a lot of people do use mass spec and Raman. We also use FTIR, which is infrared spectroscopy. I use XPS, which is an X Ray photo emission spectroscopy, but I’m also working on developing sort of tools for cheap real time detection electrochemically so I just use micro, like I sort of have developed these pattern electrodes using microfabrication techniques. So that sort of in the electrolyte real time without sort of needing expensive and external equipment, you can sort of study these degradation processes as they’re happening.

So like, one of the problems is that when you take it out of the battery, then it undergoes additional reactions. And so maintaining that environment is really important so that you can see what’s happening in the battery and not what’s happening when you take it out of the battery.

Tessa: Right. Get an accurate view of the actual environment within the battery. Assuming this technology works out, where might people eventually end up seeing it or interfacing with it, or at least, being affected by it and their day to day life?

Sophie: I think in the day to day life, my hope would be that when you come home and turn on the lights, that energy is coming from solar and wind within your community, as opposed to a coal plant.

Also right now, sort of this grid scale storage can also help in terms of, load leveling, which is this concept that like there’s periods of time when you have it like big optics in how much energy people are using. For instance, when like everyone gets, gets home, there’s a big uptick in the amount of energy demand.

The service providers are then having to use things that can ramp up production really quickly, as opposed to sort of things that have a more level output. Hydro is a like more steady output, but like, if you need a lot of energy really quickly, it’s harder to like start flowing more energy, so they use coal Peaker plants, so they can just throw a bunch of coal on and get a lot of energy quickly to meet that demand because with the grid what’s being produced has to be consumed instantaneously, it always has to be balanced on the grid. Batteries can also sort of allow for that rapid uptick with peak power demand.

Tessa: So, yeah, I’d imagine that this is quite popular with the utilities. Cause I know utilities, from what I understood have been pretty leery about solar specifically for that reason is that they can upset that balance.

Sophie: Yeah.

Tessa: Especially, like, rooftop solar.

Sophie: And then also like micro grids are really great. So then communities can be self-sustaining in terms of their sort of energy generation and uage. So like one thing that we’ve… saw, like after the hurricane Maria and Puerto Rico was a development of like new micro grids cause it was really hard to read them, build their power lines in that period of time, because it was like mountainous and all of the recovery efforts were very expensive and being overinflated. So developing micro grids within individual communities enabled sort of faster rebuilding there.

Tessa: I’d imagine it would also make them more resilient in the event of another hurricane or other sort of calamity.

Sophie: Yeah.

Tessa: When you talk about grid scale, how big are these batteries slated to be? Or how big do you think they would need to be? I mean, you were talking about the size of a small car or, you know, something that you could fit in the closet.

Sophie: It all depends on sort of what you’re, you’re working on. So for your home, it would be something maybe that could fit in a closet or like a megawatt battery would be about the size of a shipping container.

Tessa: I’m actually just impressed that megawatt batteries could be a thing. One of the things that I know far more information about than I probably should is, you know, the, uh, 1986 Chernobyl disaster. Um, and you know, they talk about megawatts as being the units, a full nuclear reactor puts out. Um, so the fact that you could store that much energy in a battery, just kind of blows my mind.

Sophie: Yeah. It’s, it’s not actually that absurd of an amount of energy, but it is a lot of energy.

Tessa: And actually that brings me to my next question, is that I know another thing, my battery development put that much energy in a container. If it somehow ends up getting discharged all at once, the results can be quite literally explosive.

And, you know, there’ve been problems with lithium batteries, catching fire in places that they aren’t supposed to. Is there less of a risk… in person that’s because lithium is super reactive… is there less of a risk of that with these sorts of sodium batteries.

Sophie: Not necessarily. Yeah. So it all comes down to energy density.

One thing also, it is if you use sort of a lithium metal battery, so one that has the actual lithium metal versus like a battery that has two cathodes that accept lithium ions, or like two electrodes that accept lithium ions, but no actual metal there. Yeah. Metal is part of what makes it really dangerous, but also it’s about energy density.

Um, sodium is similarly reactive to lithium metal, but you’re not using sodium metal. So that does make it safer. And there’s also been a lot of progress in terms of electrolytes and other materials to make it safer. Yeah. There’s been some really cool things. There’s like a researcher at Oak Ridge national lab.

Um, which I just think this is like the coolest thing, but like he put Silicon oxide in and it basically makes a non-Newtonian fluid. So if you’re familiar with like GAC, um, the stuff that you like, or Oobleck, the stuff where you like punch it and it hardens. And then if you like put your hand in, it can like flow through.

So they’ve like developed this for batteries so that if there’s like an impact it’ll harden and protect the battery. But when there’s like no impact, it can allow the battery to flow through, which I just think is…

Tessa: Assuming all this research continues to go well, what sort of time horizon do you think is realistic for this technology being rolled out and suddenly, you know, you can find it in your day to day life. Are we talking like years or decades?

Sophie: I think there’s… like sodium is years off. I think there’s already sort of grid scale options that are out there they’re are already like startups that are putting grid scale out there. Um, mostly working with like utilities, um, to do these installations.

And so there’s the company that I worked for when I got out of school, which is doing like a flow battery. So that’s like a liquid electrolyte that’s stored externally and flows through. So that allows you to scale the amount of energy you’re storing separately from the amount of power you’re putting out.

So they are not commercially available yet, but yeah, they are, do have models out there. Yeah. There’s a lot of flow battery startups that are already sort of in sort of field tests. There’s also things like the Tesla power wall that’s already out there, which is them using their excess lithium production capacity to do home-based energy storage.

And so that, that was commercially available. I think they scaled that back some, but yeah, I think we’re on the like five to ten year timeframe.

Tessa: Less of a technical question, more of a question about your sort of journey. So. You got out of undergrad, worked at the startup, and then you went back and started working on a PhD. What kind of motivated you to sort of follow more of a research, academic track, as opposed to staying in the startup world?

Sophie: I was doing research at the startup and I sort of felt that I needed to work on sort of developing those skills and getting that PhD to sort of be able to lead research projects and do that project management and team leading work in a research environment.

Charles: Well, how did you end up at your particular lab?

Sophie: A number of things I really admired my advisor and, uh, what she was doing. Um, I’m at Drexel university in Philadelphia, in the chemical engineering program at Drexel. You like apply for admission and then after you’re admitted, then you match with your advisor.

So I like knew coming in that I wanted to work with her, but it was a function of sort of a match at that point.

Tessa: What would you like to be doing once you’ve finished your PhD? You know, go back into the startup world, start up your own lab, go work for a national research lab, et cetera.

Sophie: Yeah, that is the question I’m trying to figure out. I really would, I would love to get, go to a national lab and do research there. I may go end up back in the startup world, uh, because that’s where I feel like a lot of great research is. There was a number of like stablish companies that have battery research, you know, Panasonic, Sony, Duracell.

But I love doing things that are like truly innovative. I think the national lab structure is really great in terms of getting to like, do cool research while sort of having some amount of stability that you don’t get in academia and you also don’t get in, uh, startups.

Charles: Well by national lab do you mean like federal lab?

Sophie: Yeah. So there’s the department of energy has a number of national labs. Um, so there’s the Oak Ridge national lab, the national renewable energy lab, the Lawrence Berkeley national lab, Brookhaven national lab.

Tessa: There’s one in Idaho, too.

Sophie: Yes, Idaho, yeah. There’s a number of them. You know, some of them are more focused on nuclear energy. Some of them are more focused oil and gas, but there’s a number of labs that are doing sort of innovative energy research.

Charles: Okay. So like the electrical chemists version of an entomologist going to work for the USDA.

Sophie: Yes. Okay. I, yeah, I also really don’t know where I’m going to end up after grad school.

Tessa: You know, that, that’s fair.

Charles: I mean, I feel like that’s a statement that every person in grad school can say right now.

Sophie: I got my start in science at a science museum and I have a lot of friends who work at space X and, you know, space flight was this like amazing thing that we all dreamed about, but. When you’re like, and I think also I understand how the space program has like funded basic science research and advancements and interest in STEM.

But when like the world is burning and we’re like focused on sending people to space, it feels a little discordant.

Charles: I am curious what the sort of community. Attitude towards Tesla is like, is it seen as sort of a crass commercial enterprise? Or is it like, unfortunately there’s Elon Musk at the head of it, but the work that they’re doing is real and valuable and interesting and innovative.

Sophie: I mean, I think we are… battery nerds are nerds for Tesla. I was at a battery conference in February. Uh, probably the last conference I’ll get to attend in my graduate career, but they had a, they had a model S there that we got to like drive and it was just like the coolest thing.

Charles: I love that there are enough people into batteries for there to be a community of battery nerds.

Sophie: Yeah.

Charles: I say that with all the sincerity in my heart.

Tessa: Yeah, my life is better for knowing that. So the world’s on fire and multiple ways. And we’re sending people into space, which as you know, someone who does space science, professionally, and who is also, you know, it, hasn’t worked for NASA and is a very avid enthusiast of human space flight.

You know, that is actually something we’ve been wrestling. In my community… there was a moment, a couple of months ago where the George Floyd protests it started happening because the news story broke right on the same day that a bunch of people found out. Not that they’ve got when the space science based telescope science Institute released, who was going to get to use Hubble in the coming year.

And a lot of people remarked that, you know, It was a very strange time to feel really excited on an individual level that, you know, this great thing is happening to me. And, you know, I’m going to have this amazing opportunity to do really incredible science, but at the same in time, you know, realizing that in the wider context text, it felt kind of hollow because there are these horrible, horrible, horrible things that are happening.

And, you know, again, as someone who is an astrobiologist, but with a background in environmental science and ecology, it’s something I also have to deal with. I’m, you know, looking for extraterrestrial life, which is amazing, and I love it, but at the same time, yeah. It’s like, I know enough to know the sort of, I have to hope that we can work towards a more sustainable future or we’re all going to be dead as a species in like 200 years or at the very our observable civilization is not going to be in good shape.

Charles: The way things are going…  200 seems.

Tessa: That’s a very optimistic. Yes. That’s extremely optimistic. Yeah. So, I guess, I mean, I feel you on that and I have mixed feelings about it, but on the other hand, yeah, like has working in the world of batteries of making a much more tangible contribution to maybe solving some of these problems and say, I am. Has that kind of helped deal with that sort of feeling of the world is on fire or does being in it like 24/7 make it work?

Sophie: Yeah, I mean, I think I, when the world is on fire, I was, you know, talking about the protests and stuff. I also think right. The Amazon has been burning this year and we can’t forget that.And global warming is real. I think it’s also weird because like, as research scientists, we also like create a huge amount of waste because we need everything to be. Like clean. And so we like produced so much waste just to like do research. Cause like we’re using everything one time and then disposing of it, which feels so weird in terms of the world.

I do feel like I’m trying to make a difference in climate change in terms of like renewable energy storage, but also a lot of battery nerds are not in it. You know, because of, they believe in it for global warming, they just believe in it in terms of like a cool technology.

Tessa: I, I find that a little hard to wrap my brain around, putting up their hand, if it gets us to where we need to be, you know, to have a, you know, sustainable civilization, I’m not gonna like complain too much.

Charles: One thing that I see brought up a lot is the idea that the level that we consume at is not. Actually sustainable, even with renewable resources. So is that a topic that you see brought up ever of? We not only need to engineer ways to use energy more sustainably, but we are also just, period, going to have to use less energy.

Sophie: Yeah. I don’t see that come up in my field. A lot. energy efficiency is a big play. But I don’t think it’s like motivated from a point of view of, we don’t have enough resources and I do think it should be, we, you know, there’s the like individual consumption, right?

Like, I don’t think the consumption that I make in lab that is like wasteful is on a global scheme, like making a big dent in like the total, total plastic consumption and petrochemical waste consumption. But I think there’s multiple levels because there’s like, Most of the consumption is happening in like a few companies and in a few countries.

And it’s like on us to really cut down the consumption there. And that’s, I think where the biggest gains can be made.

Tessa: Yeah. Yeah. You know, like in terms of carbon emissions, like 80% of it comes from, you know, a handful maybe at most, uh, tens of companies and the rest is like the literal other population of the planet along those lines about, you know, Equitability and sort of like the, you know, who’s responsible well for the cost of pollution and environmental degradation and climate change versus, you know, who bears the burden of it.

Um, we already talked a little bit about community micro grids and, you know, resiliency, the example of Puerto Rico after hurricane Maria. Um, do you believe the technology you’re working on can sort of help in that respect of making? I guess. Energy more widely available and maybe for lack of better term, more democratic or democratically controlled.

Sophie: Ooh, that’s a good question. I think that I definitely think batteries and energy storage can play a role in sort of breaking down these long distance power grid, like power grid infrastructures, and like move us to more localized community based. But that localized community may be, you know, on the multiple state basis, as opposed to a nationwide grid.

Tessa: So more regional than like, you know, your specifically your local neighborhood, but you know, still a bit more decentralized than what we’ve been dealing with previous.

Sophie: Yeah. And I mean, right, we already have like regional utilities. I also think, you know, we can’t necessarily have like neighborhood-based control until we have more integrated neighborhoods, because then you’re just going to end up with like pockets where there’s the resources to get solar panels and get batteries that have access to energy independence.

And these other neighborhoods that are already like subject to these like environmental penalties, like in Philly. We really like, there’s this big refinery in Philly that exploded last year and like was shut down. But there’s been specific communities that have been paying the cost of the pollution from that refinery for years. Um, and there are communities that are consuming the energy that is produced by those refineries.

Tessa: So basically it sounds like this is one of those cases where while sort of battery grid storage could be a game changer. We have to be careful not to. Replicate the same injustices that came with the S with the old system.

Sophie: Yes. And also make sure that like, right, make sure like batteries and solar panels right now have a big price tag and a big like initial capital investment. And so equitably distributed them as well as, yeah.

Tessa: I’m much a part of the solar punk fandom. So yeah, I’m all for, you know, decentralized, democratic control and energy for all.

Sophie: Yeah. There’s like a researcher at, I think it’s Michigan who like put out a really interesting paper recently that was basically like, because lower income families like consume less energy as like a basis of having less resources to be able to do that. They don’t get the same access to like energy efficiency.

And other like energy rebates and stuff. So a high consumer might be given the opportunity to get solar or get efficiency upgrades in their home, subsidized weather utility, but low income consumers who could spend more of their like income on their energy needs, but consume less energy overall. Aren’t able to get access to that.

Tessa: Wow. Holy perverse incentive Batman.

Charles: Well, so with regards to energy and sort of more widely distributing energy. Does… batteries or sort of similar technology, are they part of the conversation in terms of helping? Because different forms of sustainable or renewable energy are better suited to different environments, right? Like are batteries sort of part of the solution in terms of we can generate energy in one area and then distribute it to other areas where it can’t be generated as easily?

Sophie: Well, not really. So that’s, that’s what we currently have with our, like a power grid where you generate at one place and then you consume it another place. Um, and batteries would be co-located with your generation. So you have solar panels on your home and then a battery next to it. Or you have a big solar generator for your town. And then there’s batteries that go with that. But then rather than having to like, get energy from five towns over where there’s a power plant, you know, your whole town is just fed in this smaller grid of things, right. An area that doesn’t have solar maybe can benefit from wind or maybe can benefit from hydrothermal, but batteries really are on a local level.

Charles: Are there any sort of environments where people think where they’re just sort of no options for renewable energy sources?

Sophie:  I can’t tell you off the top of my head.

Tessa: Yeah, I’m hard pressed to think of any, mostly because there are such a wide variety of potential, renewable energy sources that, I mean, if you don’t have solar, you can have wind, you know, especially since places that usually are overcast frequently also got a lot of wind just.

Because of climate reasons. And especially also since wind tends to be higher at night when you don’t have solar. So those two kind of go together pretty well. And then, you know, you would have to be on a completely flat plane, always overcast, but that despite being completely flat plane, so there’s no hydroelectric available cause there’s no falling water.

Also didn’t have wind and. I think while I suppose, such an environment as possible, it would have to be, it would be difficult to contrive a situation where that was the case.

Sophie: Yeah. I think like in cities and stuff, there’s definitely like, it’s harder to, like, you can definitely like plaster buildings with solar panels and stuff like that.

There’s also like cool stuff with like PZ, PZ, electrics, or things that like, um, basically when you put strain on them, Like it converts mechanical energy into electrical energy. So like when people are walking through a subway turnstile, they’re like feet walking can generate some electricity, which isn’t a ton.

But if really like from an urban design standpoint, there are ways that we can like change cities to be able to harvest the energy that’s there, but it really takes a mindset change.

Charles: I mean, we can talk about being trans in science if you want, but we also don’t have to.

Sophie: Yeah. I think it’s a, it’s like both a huge thing and just like a, Oh, like there’s more to me than that.

Right? Yeah, we are, and we aren’t defined by it. Yeah. I, I mean, I do… long before, like I knew when I was like a kid, but I didn’t come out until, until I started grad school.

Charles: Can I ask about how old you are?

Sophie: I’m 30.

Charles: Okay. So yeah, so all of us are sort of, because I’m 27 and Tessa, I think you’re 33, right?

Tessa: Yup.

Charles: So we’re all in this weird little bubble where like, because I came out when I was 18 and then I started transitioning like right at that point and … the extreme degree of difference in terms of public acknowledgement of an knowledge about trans people had like completely flipped within the first few years after I transitioned. Which is a weird, like micro generation to sort of be involved in if that makes any sense.

Tessa: Yeah, I know what you mean.

Charles: and so it’s cause like, you know, cause when I came out, when I was 18, the notion that you could come out as a teenager in high school was completely unfathomable and now we’ve got a bunch of kids running around transitioning when they’re 12.

And I am happy for them, but I’m also very jealous. But I’m happy, but I am jealous.

Sophie: yeah. Like I feel like life would have been very different if I had been able to like, explore my identity more fully when I was like eight and knew I wasn’t a girl than when I was yeah 26. And was like, Oh, now I have time and space to explore this.

Charles: So is there anything that you didn’t get to bring up that you would like to bring up or a message that you want to impart to the world?

Sophie: I think a renewable energy future is important. And so everyone should take that in with how they consume energy and how they get their energy. And also, I just want people to know that trans scientists exist and trans scientists exist in grad school and that this weird generation that grew up before the trans reckoning, but now.

It’s sort of young adults in the trans reckoning that we exist. You know, I think it was hard for me for a while to find other trans scientists. And so,

Charles: So if, if people want to find you online, where can they look?

Sophie: Um, you can find me on Twitter @sophielee.

Charles: You can find me on Twitter @cockroacharles. And Tessa?

Tessa: you can find me on Twitter @spacermase.  

Charles: You can find the podcast on Twitter @ASABpod or at our website asabpodcast.com. Thank you for listening, catch you on the flip side.

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