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Inside Olas Cell Factory I Spoke To Their Engineers

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TITLE: Inside Ola’s Cell Factory: I Spoke to Their Engineers CHANNEL: Gareeb Scientist DATE: 2026-05-03 ---TRANSCRIPT--- X Tesla Xffort just say please do not feel awkward to say no [laughter] I have extremely specific questions that factory where we use a very unique process in uh developing the electrodes right uh which is called the trieler process but

why did you all choose this you know why didn’t you all take the proven approach of liquid uh or uh [laughter] of LFP NMC happen or no that is also yes this is your point might think we are handling graphite so it’s easy but actually it’s a more sensitive process people don’t know that it’s I’m surprised that you observe that and you’re asking me that question but yes that’s I don’t want to say what it is so now answer I’m trying to [laughter] so electrolyte is our own IP right you know we have we should not discuss that right let’s not discuss that it’s an IP yeah it’s a very critical we would not like to discuss this fine that is fine [laughter] it is an IP thing I need like million cans more than million cans a month at this scale at this accuracy yeah vending out so at least delivery 10 15 uh Okay, those are very good questions actually. I think I in the last I think you had one hour two there you had gone really deep looks like [laughter] you can come join us paper 46 46 anode electro anode. negative sidemater NMC manganese cobalt LFP dry electro technology typically major manufacturers except maybe Tesla silver sorry aluminum foil And of course drylically. floor. Aluminum rollers again topic. But of course, sheets of plastic piece. And then steel canging. Finally. Interesting. Welcome to this conversation. I don’t really have a flow. What I like to do is start from uh basics and then drill down and move up. Yeah. Uh so but before we move on like can we start by introducing yourself? We start from you and we’ll go towards Yeah. Rajes. Yeah. Sure. [laughter] Um I’m Rajes. Uh so I’m working with Ola now almost 6 years. So my uh background is I’m working on lithium uh battery industry now almost 17 years. So I used to work in China and Japan before. uh come and join Ola. So I head the R&D uh so I’m responsible for getting all these products ready for the factory to produce. That’s my basic. Okay. So the R&D battery sell R&D. Yes. Yeah. Right. Sean. So I’m Sean. Um I’m the chief operating officer. Uh I’m responsible for I’ll say day-to-day operations across the entire business as well as strategy. I look after both the electric side and the cell sell side of the business. I’ve been in the automotive industry for about 35 years. Okay. I’m Bala. I head manufacturing engineering here and responsible for running this factory with uh throughut and RAM. Uh before this I was I started my career in semiconductors. I was in semiconductor industry for uh around 8 years in Intel uh premier R&D material science uh next generation nodes all of it in US and then I joined I was in Tesla for 2 years uh I was working on a similar battery format and chemistries and then in Ola I’ve been here for close to 4 years now uh so I moved I was in US after around 16 years I moved back to India and happy to be doing it for the country and we’re all excited about is what Ola is doing. Yeah. Right. So just to recap for myself, Bala the overall battery cell person manufacturing. Yeah. Sean the CEO and Rajiv Rajes. Rajes the battery R&D person. Yeah. Okay. Great. So uh you know recently Okay. Before that I think I want to start with what like from the expert what would you if a kid asked you what’s a cell what what’s the definition of a cell so uh cell is a electrochemical device right so uh it basically store energy that’s it very simple uh you know uh physics if I say that it is it just store energy now how store energy um it has um uh two parts one is a cathode and another one is an anode and in between there is a polymer film which actually separates the anode and cathode charging during the charging process lithium moves from cathode to anode and during the discharging process when you take the electron the lithium goes back right it’s as simple as that. So it’s a very uh simple uh energy device. U right now almost all the cells are typically with the lithium movement inside but there are you know sodium based uh cells which are upcoming. Okay. So if I take a cell suppose this uh if what would be the parts of a cell if I had to open this what would be in it? Yeah. So you know see what you see outside is the mechanical parts. So where you can say that you know that’s where all the chemicals are stored inside right and you know it’s a very strong uh casing because u you know as you know the lithiumion batteries are uh you know very safety sensitive devices right so you need a very uh thick casing once you open the thick casing then what you see inside is a jelly roll so this is cylindrical cell if you go to a prismatic cell then it will be a flat jelly roll uh in U pouch cells you see basically stacking of electrodes cathode anode cathode anode. So when you once you open then it’ll be like a two long electrodes one cathode electrode one anode electrode and in between there will be a separator and then it will be just wound into a jelly roll. That’s what you you going to see inside. And then there will be some liquid inside which is nothing but the electrolyte. Okay. Which which is the medium for lithium to move from cathode to anode. That’s what you want to see. So if I if I open this, basically it’s a sheet of anode, sheet of cathode separator rolled up. Rolled up filled with electrolyte in a metal casing. Yes. With two buttons on top. Yeah. Well, one positive and one negative. Plugs on. Plugs on top. So now coming to the materials, what is this anode cathode made up of? Uh so see um there are multiple C so typically the cells are called based on their you know cathode active material which is used. So there are typically u three uh sorry two major chemistries which is called NMC which is nothing but nickel magnes and cobalt. Uh the second cathode active material is LFP lithium iron phosphate. Um these all are um uh so for NMC it’s a uh a metal oxide in inside which lithium is uh you know stored so it’s like a nickel magnus cobalt oxide and inside that you know lithium is stored in the uh latises on the anode side uh typically it is graphite so graphite is also having layers because like that’s why when you write you know with a pencil it basically removes one layer right? Yeah. So between the layers actually the lithium will go and set. So typically it is graphite. There are silicon based anodes also you know getting ready for the future. Tesla is uh Tesla is working. We are also working uh let’s say you know in our future products. So yeah these are the major uh like you know the cathode and materials. Great. So I think this is the basics. Now let’s get deeper. If if hypothetically I bought a bag of nickel, manganese, cobalt, lithium, lithium and iron and phosphate and put it on the table. What needs to happen to that where this factory can kick in? From the or to what stage does it need to be bought where this factory can finally play a role? Yeah. So from the or the materials are mined and then there is some processing that happens with the midstream processing that happens in outside India right now but we there are plans for India to also to go into that we’ll get to that later but essentially there is uh cathode material which is NMC and anode which is graphite it has to be a battery grade material that gets uh manufactured in these factories and we qualify let’s say Rajes’s team will qualify let’s say a a portfolio of these and then uh there’ll be different kinds of NMC’s, different kinds of LFPS, different kinds of graphite. He will qualify a portfolio of these and then he will say okay these are the manufacturable ones and then I essentially go and check the manufacturability with respect to okay these are the products that can be ramped up to a high volume manufacturing and then we essentially do that in this factory and then we drill down and we finalize the chemistry uh where like you know we say that okay this is the one that chemically it is stable it is a manufacturable process and then we take that chemistry to a ramp to go for a high volume manufacturing. Okay. So even something like graphite has to be imported. You would think like pencils have been made. So that’s not the same class of graphite. Yeah. Battery grade is you know basically when you go and mine any of these materials, right? You know something what it comes with that material is iron, right? Iron is one of the biggest impur. So [clears throat] graphite is not only mining. So uh you know these days from uh petroleum petrol coke uh that that can be converted into synthetic graphite right. So the m the most important part is actually the uh uh impurity which is uh the iron. uh so you need to have uh ppb level of iron content which is something like parts per billion which is like less than 10 10 ppb to reach 10 ppb the it’s an extremely uh complex uh you know purification process so you know when you get a normal pencil type of [clears throat] graphite you won’t be able to use it the technology lies in the purification and uh sporadic uh uh you need to convert into a spherical structure hm right the active material. So that’s where the majority of the technology is lie. So to answer to your question getting graphite probably easy but converting into a battery grade is the difficult. Okay. The ecosystem itself is quite complex like you explained but it’s it’s possible right now in the country the demand is increasing. These areas is the first gigafactory. We have other gigafactories coming up. So that as demand increase this ecosystem will build in India also. So it’s not that it’s not possible to do it. It will be built soon and graphite is actually one of the ones which will come sooner than cathode. Yeah. Okay. Yeah. From a factory point of view I I’ve quality area where the material comes in and it gets checked. How so how will that scale because now you are doing how 1.22 22 g in that area itself you’ll be able to move because uh know repeatedly I heard that this is the choke point like if things are bad from the start then everything the chain whole chain breaks down so how do you ensure that so number one what we do is we make sure that our supply base we’re using a global supply um supply base right now so it’s a global supply base which a lot of I’ll say traditional cell manu manufacturers are using right so we come from a well-known baseline to start with what we do once it comes here that lab is we only qualify it that’s it so we’re just checking it’s no more than a qualification process and that’s what we’re making sure because the goods have got to be transfer transported from global to here so that’s that’s all we do there something I would like to add there is uh what you saw is only like for the incoming right if you’re thinking about sell quality itself which is going in the process we a lot of inline methology that is there. We have X-rays, we have spectrometers, uh we have vision cameras, the whole automated line has all these things and every product there is 100% sampling where it is taking decisions in the equipment to reject and pass. So that’s the quality which is the real quality which is the product manufacturing quality which is happening inside the equipment itself. That makes sense. So yeah. So yeah and again I’ll I’ll add a little bit more to that. So think about like um Bella said every stage is has quality checks, verification and traceability as it goes through every every stage through this factory. Yeah. So those labelers they were uh Yeah, that’s right. So you’ll see that and and basically so our our overall principle here is built-in quality through every stage through the supply chain stage through the suppliers right up the value chain right to the end. Yeah. to break it down from the scooter from the battery pack to the cell to the raw material to the mechanical parts everything is traced. So we can trace it back to the supplier batch. Okay. Yeah. Yeah. Okay. And that is standard across industry. Right. Yeah. Yeah. Right. So uh you know now we have that whole u entry point we have done the quality qualificationf and all of that. Now comes the part where we are dealing with electrodes. So can we talk about now we have spoken about anode. The anode uh is graphite right? Yes. I have been reading a lot about anode poracity like how how good the layers in the graphite could be such that you could impregnate it with lithium or uh I don’t know impregnate is not the correct word I think. Uh what is the right store? Sure. I I mean um um so the procity probably like you know um there are multiple ways you can define the procity right so in a electro level um you know before the even the cell uh uh you know even even the electrode is made there is a 6 to 8 months of uh let’s say uh activity where the cell is getting designed cell is getting simulated uh against the requirements of your customer right so every cell is basically very unique uh in nature. So during that time that’s the time where we basically define the procity right. So procity is nothing but you have a uh active material when you uh do the coating of the active material how much pores are there inside the electrode where if you do a cross cut cross-section so typically electrode is like 100 micrometer in thickness. So if you cut the 100 micrometer and then use a scanning electron microscope and check like you know what is the number of pores. Uh now what is uh why this is very important because u when you put the electrolyte inside electrolyte have to travel everywhere because then only like you know the lithium can go and find its spot inside the anode or cathode it you know it’s important for both cathode and anode. So ploity is kind of a design specific requirement right based on whether you wanted to do a very fast charging then you will have a different uh posity if you wanted to uh you know pack a lot of energy then I don’t want to give a lot of pocosity because you know I can use those pocosity for packing more material so your uh so then it will become a energy cell so typically it depends on it’s a design parameter rather than a you know process processing uh parameter. So it’s a design parameter which will be given to the manufacturing uh to reach that uh particular number so that it meets the end goal. Okay. So this porocity is ensured in that QC level only that you have so okay so let’s talk about the cathode. Now we have in front of us NMC and LFP cells. Uh why start why did you start with NMC? Well, um should I you go you go. Uh so you know see our first uh scooter right on the S1 Pro um so it uh uh there was a requirement right requirement was nothing but then know we need to pack around 4 kilowatt hour uh because eventually the scooter is made for the customer to experience especially one of our thought process was customer should experience the uh like the longest range right correct. So if you have to give uh that feeling to the customer the most important thing is you need to pack more energy right so uh between let’s say LFP and NMC there is a uh NMC have an advantage of 35% more energy uh stored in the same form factor right so our decision was to go with the NMC because we want that 35%age of extra energy go to the customer right so that was the reason for us to take the NM NMC as the as our first choice rather than LFP and discharge current also, right? That is also higher, right? NMC can have higher discharge current also, right? Uh yeah. So I mean it uh I would say like you know you pack more energy, right? Pack more energy you know your motor gets sufficient energy from the you know high performance speed performance. So let me try to sum it up for the for the team. So packing more energy over I’ll call it over a smaller weight. Yes. And giving an experience to our customers for longer range on their product. So the more kilometers they can achieve on a single charge. Okay. Uh specifically it’s a very specific question. What is this ratio like 811 NMC 111 what if? Well, I can give you if you’re uncomfortable to just say pass. I I’ll give you a very generic answer to it. uh see uh so the the overall you see the uh lithium man uh cell uh industry right you know so from 1991 uh from the Sony Sony used lithium copper dioxide um uh and then uh you know slowly like you know in 1999 that’s where the to to access the full lithium from lithium cobalt toxide you know people started putting nickel and manganesees as a ratio So 111 is nothing but equal amount of nickel cobalt manganesees right and then uh you know the uh the technologies evolved and uh you know we have like 523 62 811 and uh and now it is 955 so almost 90%age of nickel and uh you know 5.5 percentage of uh cobalt and magnes so I what I can tell you is like we are at the cutting edge of the technology uh in terms of our uh our products right uh so yeah that’s what the answer okay please do not feel awkward to say no I have extremely specific uh questions so because I uh there’s know lot of talk in general trend of moving to a higher nickel content moving away from like lesser cobalt so is this something Ola is also pursuing uh to a higher energy density cell it’s in our road map right you know so we are you know as every cell company. Uh we also wanted to give the customers the best experience. So uh typically best experience comes also from uh you know the higher energy density. So of course you know that’s in our program. Okay. Uh we will slightly get more deeper. Uh the anode is wrapped on copper right or pasted on copper. Pasted on copper and cathode on aluminum first. Yes. So this factory can it do that process? I mean I’ve seen some of it. I don’t want to tease it but uh can you do on foil uh deposition of what level? Like because I saw uh at least for the cathode there was already a black layer deposited and on on top of that NMC was being deposited. So how first principles are we getting at this fact? So that black layer that you’re seeing is just a part of a resin. It just helps attach the anode and cathode to the foil. It’s a very standard process. It’s just like a addition layer that helps. Right. The actual the actual chemistry is happening in the mixers where we have a a proprietary mix ratio of the binders and uh the active materials and that is dispensed onto the foil. And when you’re pasting this this black layer that you saw, though I know it looks like a coating, it’s not the active material coating. It’s just a resin coating. It allows you allows the active material to kind of bind onto those layers together. And it’s a um Yeah. Yeah. It just uses heat and u like uh line loads to essentially uh stick onto that material. Yes. Yes. It’s probably like just to add with Bala [laughter] what you see here is actually you know one of the world’s uh you know uh best gigafactory where uh we use a very unique process in uh developing the electrodes right uh which is called the trieler process. So uh the black coating what you see on the incoming foil is just to support the dry electro processing right you know so once you make the self-standing film you need to like laminate into a something right so that’s what the it’s a it’s just a carbon with some resin it’s heat activated yeah it’s an activated uh during the process let’s talk about a dry electrode because you know uh people think mixing things is a very simple process But getting a homogeneous mixture that is evenly spread out, different materials, different weight, different molecular weight. Yes. You know how I know you can’t tell me exactly how you did that? But then some of the engineering challenges that came you know getting a dry homogeneous mixture like how do you approach such a problem? So um in the whole line right the most challenging piece to ramp up is essentially exactly what you said is the mixing uh and for those reasons as well because you know I cannot have I’m talking about let’s say a 600 kgs right and I have to every part every mo every NMC particle has to be quoted exactly the same way so that that translates to the electrode and then the electrode is going to the cell I cannot have high density low density regions elomerations and all of that is challenge we have. Now what we do is typically there is an architecture on how you ramp it and uh it’s we start with u like at BIC where we have a smaller mixer that small mixer only yields around 10 kilos right and the composition itself is defined over there with respect to the percentage of binders and such so that that composition is yielding the right electrochemical output for the cell. Okay, that’s where that freezes. We do have a pilot line where that 10 kg is scaled to 100 kgs first and then that 100 kgs is typically around 70 kg you know uh that’s how much we fill and in that process we define the architecture of the mix on how the steps needs to be put together with respect to what should be the speed of the mix how much time should it spend what should be added first what should be added later how much temperature I need to maintain this is what is going on in that n once we fix that architecture. That architecture is itself translated to the larger mixer where we use the same architecture and then we have the motor torque power ratio with the tip speed ratio. We have all those mass calculations and how it rotates and then essentially that architecture when we scale it here it uses the exact time frame and the simulative speeds where we use it to six let’s say the 600 700 kgs and essentially then what we do is each those each of those steps we have specifications let’s say I have five steps or let’s say 10 steps in the architecture each step will have a specification which will be checked in the quality and that is my local targets and how I scale it up and that specification is coming right from the 10 liter mixer to the 100 liter mixer to be tested and then translated to the larger volume. So that’s how we did. Wow. Okay. [laughter] Just to make it very simple. Sometimes I’m beating a egg and even I struggle to mix that egg and yogurt. [laughter] I can’t imagine dry powder being mixed like do you even have to do CFT for the blade and how it will interact with the so start from a very the material selection because you know you said like you know different molecular weight different densities right uh so we goes through very u uh uh I would say you know a serious um screening of materials Right. Um it’s not directly like you know you take two three materials and put together and then mix and then they mix together. So there is like uh 6 to 8 months of uh very serious uh screening process uh happens and then uh based on that materials we develop the basic process right you know which works you know as you said like you know if you mix everything looks uniform and that process will be then uh handed over to the manufacturing engineering then they do all the CFD uh you know activities for designing the blade shape or maybe the you know the the even the what is that the mixer wall design etc. So it’s a very I mean tedious job. Yes. Uh for like a year this is an interaction process right. So when we initially started the conversation we talked about the portfolio of the materials. So I will say that I have challenges with these materials. Then he will have more options for me based on that. So that is something which happened over the last couple of years where we work together to define what material and what architecture is fusing together to bring this product. That’s how it works. Okay. So this is the kind of nuance that is lost when we speak you know because people will be like just mixing materials but there’s so much that goes into something that looks simple on paper. Yes. Uh now on that note why did you all choose this you know why didn’t you all take the proven approach of liquid or uh [laughter] uh so probably like you know uh I can answer this um uh see when we decided to uh you know uh start the cell manufacturing um uh one of the u first decision what we made is um when we do the cell right you know what value we bring uh to the customers. Uh so that’s why we uh started uh making a bigger cell because um based on our calculations etc. uh you know we were expecting uh you know as I said in the beginning right you know what experience you give to the customer um if you go with a 4680 type of cell which is double the size of sorry five times bigger than that 2170 cell which can give you around 20% more range right so instead of 4 kow you can pack around five 5.2 2 kowatt hour in the same given space you know no change in the space. So that was one of the decision and then second decision is like um when uh we do this process right uh when we when we start uh developing our own cell uh another point is actually cost how you can become more cost effective how you can more become more resourceful uh you know you see this factory like you know this factory can go up to 20 G right it’s just because of the dryer process because the wet electro process itself will take around 70 to 100 m of uh you know the factory right to give you a perspective if I can add uh if we expand to 20 you see the current building footprint it’ll be exactly the same footprint just for electrical because there’s a drying process okay that’s a very long oven right you know so so definitely like you know utilities are required for those you know ovens and you need a NMP recovery because you know you use the uh solvent uh called NFD. So it’s a uh expensive process. So uh when we um when we decided that when we we we will make a cell, we also decided that we will make a cell which is cost efficient uh you know technology the top class technology uh and then uh it will give a best experience to the customers. So these three things were uh you know decided uh these were the decision makers for deciding that if I like to add to this right fundamentally that is Bes’s vision to the company also like even in the scooter we have gone to buzz bars like uh the cables are very they’re topnotch and even in this he said if we are making it it has to be the next generation and it has to be whatever is every process has to be the next generation process and for that electrode drives every company’s is trying to reach. We are one of the few who have made it commercially first there. Um and then uh even for the form factor this is the next generation. Yeah. And I think know people I don’t think many people know that you’ll uh make your own electrolytes uh electrode sorry because uh there was a assumption that it’s a assembly plant but when I saw there’s a lot of stuff happening correct people people should know. Yes. And I think one more thing with the liquid electrode would be I would guess after it dries it will do leave holes inside. So less energy density I guess. So I know the you know of course you know when any solvent evaporates it will also put a lot of pores but there is subsequent process for calendaring right so when you do the calendaring it will be compacted again right but here then the dry electro process you must have seen right you know the calendaring happens on the electro production line itself right? So you don’t need to do a secondary calendaring. We actually skip two steps when you move to dry. One is the coating itself is happening in the calendaring only. Right? The other is the vacuum drying is an additional step which happens in wet. Right? You again you have to take it to a vacuum oven and dry. So that process essentially two processes that are eliminated and like Rajes was saying you you just think about the scale of this factory you have to and when you have such a big manufacturing line you have to run air handlers and dry units. It’s a lot of energy consumption. So our opex cost on per cell is actually lower than a comparative wet cell because you know that’s how we are able to keep the cost down including manpower because now when you have a larger line you have more manpower more opex all of that is and you are a few lines on this. Yeah. So and I’ll just pick up what Bella says. So you’ll see this factory what you’ve seen so far 2.5 g scaling up to six all that’s ready to go this building that you’ve got 20 gawatt in this space so if you actually go and compare what I call our density of gawatt per square meter each we would be one of the highest density of equipment processing cell output globally. Yes. Absolutely. Globally, right. And that’s because of the technology that we’ve chosen and not only in form factor, but chemistry as well. And that’s really what’s going to give us our leading edge because that then turns into a better quality product at a cheaper cost to produce which then goes into our final products. That’s what it’s all about. Right. So also I’ve noticed in that uh model which is there at the entrance it’s a modular uh like you go on adding units. So was this like uh like how how how does it work? So the factory is designed to move from left to right in terms of production. Yeah. So yeah so that’s how you Yeah. Okay. So yeah it’s a very linear flow. You have an incoming warehouse on this side and you have an outgoing warehouse on this side. And as we add lines, we just keep adding like you know Nexures to this building so that that flow is the same but uh it can just organically grow and then we have land all of that in the backside that’s already allotted for us. Then essentially we have until 100 G secure and maybe even more as we are generally like you know we are increasing the generations we are able to fit more capacity inside. So maybe this can even go to like beyond 100 g. Okay. Yeah. And and it’s fair to say when the guys design the factory we always look for single piece flow that’s very important as we go along and more important again is scalability right so we we want to invest in the right amount of capex at the right time and then as the market grows then we’ll invest more and we’ll scale accordingly okay so moving so from a factory point of view uh how does the switch of LFP NMC happen or are you going to add another uh so it’s a good question so essentially that chemistry right initially defining that chemistry the magic happens in R&D right where they’ll say but this factory is funible because now in the same mixer I’m just making a different recipe now right and the coding process and all of that there will be lot of work around process tuning but this factory itself can adapt to any chemistry as we’re doing and including the generation the iterations of the generations of those chemistry correct Right. So that is fully functional uh like functionally this can adapt all those technologies including the form factors if you see you have different form factors because the radius is the same that’s becomes limiting in the assembly line but the height of the cell is also funible within the line. Okay you can there’s a limitation can go up to 46 200 but uh yeah that’s what we do here. Okay we’ll come to the form factors. I have a question uh but I have a form factor question before we’ll move deeper into this. I see yall are using different terminology like typically it’s 18 650 21700 here it’s 2170 uh 4680 like uh [laughter] this is on because I I make drone I fly drones so I buy sometimes cells and I’m building a pack now with Molly cell so why why have why have remote few years back I think when 4680 got introduced that’s when the nomination changed a little bit it’s just an industry So you know 18650 was u so it’s not it’s nothing but you know like 18 is the diameter uh uh 65 is the height. So basically this was uh I mean very long back uh you know the Sony’s terminology of 18650 and then it was like moved to

  1. So 21 is diameter. So 21 mm of diameter and 70 mm of height. So that zero came from that 18650. So what we thought is like you know it’s uh for to make things easier for people to understand

you know we just said it is 2170 and 40 is 80. I mean what’s the point of putting zero? [laughter] That’s the right terminology. I don’t know. We should go back and ask who added the right I was confused when I’m talking to them. I’m intermixing 21700 and he’s saying 2170 and Okay. Yeah. Okay. Understood. So I’m building a drone pack with Molly. Oh nice. So I bought few 21700s. So yeah be I mean since we are on that form factor why did you stop? Did you ever had production runs of 2170? No. No. This has always been a pilot. No. So uh you know so um in the early stage right you know in 2020 2021 uh time we used to uh you know uh produce this on pilot scale. uh because you know uh why we used to do it on pilot scale is faster screening process right we can do the material screening uh uh you know in the this is a very wellestablished uh you know form factor uh so that’s why we used to do that but when we move to uh and even uh see the if you see this 480 right um every part of this uh structure right you know uh we have our own uh IP right uh every part of this mechanical structure. Uh and then it will definitely take us for some time to develop and then ensure we are uh we are completely safe in using these uh structures right. So uh so mean uh during that time we in the beginning right you know to prove the chemistry to check the material compatibility and all we used to produce the 2170. So we have a line uh 2170 line in the uh battery innovation center. Okay. Uh we’ll jump back. Yeah, let’s uh I think we have some new stuff on the table. Uh let’s let’s actually come before we go to the form factor come back to the cathode and electro uh anode. So I think anode we anode is relatively simple in the manufacturing line, right? It’s already uh the graphite is already on this role, right? No no no no that is also is here this is your foil that’s coming from the supplier this is coated with anode the mix is mixed inside the mixer and we coat it and uh anode is actually very sensitive because for contamination and the impurities and homogeneity and cathode is a little bit more forgiving [clears throat] and uh so actually though uh it’s since you might think we are handling graphite so it’s easy. Mhm. But actually it’s a more sensitive process. So our specs are actually quite tighter on the anode side. It’s and cathode also. But uh from a cell perspective it is more sensitive to what’s in the anode. So maybe just to add uh one uh simple uh uh or this is like globally also true whether it is dry electrode or wet electrode. Um typically the performance of a cell uh 70%age of the success is basically coming from the uh electro uh production right and 30%age is on assembly because you know rest of rest all the process right you know your slitting process you know assembly process everything is a mechanical process but the uh the heart of the cell is basically the electrodes electrodes now if you don’t make a proper electrode then your your cell is not not going to perform. So you may see that like you know you get this cathode anodactive material cathodactive material just put it on the sheet. No. So you know any uh you know failures in the cell industry if you see uh uh 99%age of the time those failures are basically the failure of the electrode rather than you know any other process in the they’re not able to scale up the yield are low and this max the almost 80% of the bomb is in electrode right so it becomes the most critical process to hit yields and ramp up and through and stuff yeah I saw there’s a machine that was going back and forth seeing the heights of the uh electrode on top of it. But then uh so eventually those rollers which are again it’s too deep of a question but uh too niche those rollers that are pressing the material on top of the electrode they also must be wearing off over time right? Yes they do. Yeah. So how do you compensate for that? Uh so what we do is uh that’s a regular maintenance procedure. So essentially if you see in anode it doesn’t happen because anode is graphite the material itself is softer uh NMC is ceramic right so essentially that can wear out the rollers but now the rollers see rollers technology itself is coming from a very traditional industry for let’s say paper manufacturing and textile and there are other calendar rubber all of these have these uh very high precision rollers right now there are coatings on top of so that itself is a separate very deep engineering work that we have to do here because the coatings have to be checked the hardness of the coating. There are certain HRC rating that we need to meet so that that coating that’s on the roller can actually take this NMC material and doesn’t wear out as much as what we would need to run. So, but it still wears out. Let’s say we will have to do a roll change every 2 months. But that activity we have a supply chain activity for that where the roles that come off gets recoded comes back and then the whole process of changing that happens within a day right so uh absolute it’s very uh like many people don’t know that I’m surprised that you observe that and you’re asking me that question but yes that happens in wet dry both the processes this roller wear out is there only for cathode yeah because I visited a CNC uh company in Bangalore and uh they they were working on a CNC that had to do few microns of tolerance. So they were repeatedly checking with the laser and seeing if that tip has worn off. Yes. And then you have to calibrate that tip for this new and you go back and forth if I can add something. So that is very important because my spec of this electrode is in within microns and single digit microns. I don’t want to say what it is. So now so that it’s there in the process. there is a powder flow, there is a film flow, all that has to be maintained, right? And [clears throat] that is causing this micron level fluctuation in the process itself. Now if I don’t have my roller, if my roller itself is contributing, let’s say even 10 microns, all that will be translated to this, right? Right. Which will essentially not be qualified for this. That is the challenge in manufacturing for electrode. So we have to make sure um let’s say what we do is we actually reverse the profile because when we change the temperature, the temperature has expansion. We have an expansion on the roller. We have to reverse the profile of CNC so that that is compensated and straight. So that that micron level is not into this and that is used to code this material. It’s like a whole chain and everything has to engineering is lot of engineering in that also like you know we took like couple of months to even uh fix that part of the process. Right. Right. So before we move on u I think you have done with both the electrodes uh uh what I wanted to ask is there’s a lot of talk I think for the battery day Tesla was talking about eventually moving to a pure silicon anode uh I think they are already mixing some silicon in their anode already. So what is about what first of all what is it about silicon that you can store more lithium inside uh the layers and secondly what are you all doing with this uh see the [clears throat] so if you consider silicon uh you know uh if you just compare with uh graphite graphite graphite is having somewhere around 350 uh mia per gram so per gram you can store uh 350 uh mia of mill mh of capacity whereas uh uh silicon can go uh let’s say 3 uh 3 3,500 mh per gram of capacity if you are going with 100% silicon and silicon also have different variety silicon oxide silicon carbon mixture etc but the problem with silicon is silicon expands 400 times right so so what happens is when silic so there are two different processes um In graphite it is typically intercolation process whereas in silicon it’s an alloying process. So silicon can store more uh you know it’s because it’s allowing a reaction rather than storing you know between two layers right uh now the problem with silicon is you know it expands 400 times so we need to somehow ensure the silicon is not expanding right now the one way is uh but you also wanted to increase the energy stored uh uh uh energy density higher inside the cell so what you do you basically start mixing uh silicon with graphite right so that you know the expansion is minimum which is controlled within let’s say less than 6 7% and which is manageable inside the cell right 5 6%age of expansion is manageable within the cell the cell in architecture is uh made like that so if you see globally right um everyone is started now started using uh silicon uh somewhere around five to six percentage age is kind of uh uh uh getting very quite common. um going to 100% is everyone’s wish right you know to go to 100 100% we need to uh have such a first of all such a material to develop which is not expanding we need to somehow protect the silicon and then it never expands uh or maybe a structure like you know silicon nanowires silicon nano tubes you know different ways you can manage the expansion um so everyone want to go to high percentage of silicon but there are technology ical improvements you definitely have to do 100% silicon maybe uh it will take quite a long time I would say uh you know so yeah we also have the road map of getting into silicon that’s a simple answer to say okay uh I was so like I said right I was building a drone pack so I was checking Molly cell versus the cheaper uh sales that come in and I was seeing the opening uh like tear downs of them and I saw that Molly Molly cell cells specifically had a lot of tabs uh compared to the cheaper cells and hence you know something like a P42 can do like 42 amps continuous uh 50 plus amps at peak in this case there are no tabs I see on the you have full tabs right so if you see I know the answer I’m trying to [laughter] uh so so in a typical cell you will have like you know some uh uh nickel tabs which are coming out right and then it’ll be connected to your the mechanical components. Correct. Um the number of tabs are typically defined uh again based on the end use right. So since you said like you know it’s a let’s say drone battery drone battery you need to basically discharge faster and also probably charge faster right. So there is something called as current current carrying capacity. So based on the current carrying capacity and also the thermal behaviors of the cell you typically define the uh you know the tabs. In our case what uh you know what happens is the one edge of the electrode itself if you see that electrode right you know one side of the electro is completely a tap. Now what we do we basically do a flattening of this tab using a tap flattening machine and then uh the entire tabs will be connected into your uh you know uh uh your this one yeah cap uh uh this is the current uh current collector. So which goes inside. So this on the aluminum side it will be connected here and through which and then this will be connected to your uh rivet side. So this on this side. Yes. Right. And then uh so that means actually you know this can carry a lot of current because it’s a direct connection to almost all the electrodes. Just to simplify. Yeah. Now let’s say if you have an electron all it needs to travel is here. Yes. Now if you have only few tabs on in like 10 m it has to go all the way up to that current. So the electron path is the shortest essentially with the table. So it’s nothing but resistance. No uh you know longer the uh so it’s everything will get converted into temperature. It is just because of I² R current multiplied by resistance. So I would guess the uh anode and cathode are slightly dislodged from each other because when you press them on top you don’t want them connecting. Yeah. So there is something called as overhang. Overhang is nothing but you know you you don’t you don’t want your anode and cathode to touch because the moment your anode and cathode touches it’s a fire as simple as that. It’s a short anode is always wider than cathode. So one is negative and one is positive. So I’m wondering doesn’t the electro electrolyte contact through the top bridge to the electrolyte is not uh electrically conducting. It is ionically conducting. Oh okay. So you know so if you put the electrically conducting then like you know you can you can’t actually shuttle the so then what happens electron will directly go through the anode to the cathode or cathode to the anode. So that’s a short. Okay. So let’s talk about u electrolyte. Do you all make your own or uh how is it? So this bottles uh we’ll talk about the process but uh no so the electrolyte uh is our own IP right you know we have u u uh in this particular cell itself we have uh more than 100 IP uh our own intellectual properties patents granted patents uh you know applications etc. uh the electrolyte composition is one of our uh you know core uh uh you know IP I would say and uh we we work with the supplier directly and then supplier makes that electrolyte for us. Yeah, according to aspect he’s keeping it simply. I’ll tell you the challenge. [laughter] Tell me the challenge. Electrolyte typically for vet which is a traditional industry is a it’s available and it’s easy because there is lot of literature which will support the research right what you’re doing. The challenge we had or he had is u because dry has special uh polymers in it binders and polymers. So the electrolyte development for this particular cell was way more challenging with compared to a wet because the literature is something we were developing during trials and stuff right? So yeah so for dry actually you need a separate electrolyte I mean which uh uh as you said like the binder that’s a polymer you know polymer have certain reactivity so to protect the polymer also we need something to go inside the electrolyte so yeah so that’s why we you know you know we developed the composition uh and then we started producing it with our supplier okay I was saying the process not here fully but in general You know it does not feel. I used to think filling electrolyte is like a soda can. You know how it comes around and you pour it in. But I learned that you are supposed to pull a vacuum drop the electrolyte so it gets sucked in into the electrodes. Yes. And then here I learned they also using pressurized nitrogen to push it in further. Yes. Yes. So this this is new this nitrogen thing. Uh why like why was the need to come up with that? That is too much of a processor. I have to tell them to stop explaining. [laughter] But essentially, so the electrolyte itself has to be soaked fully in the this thing, right? There are some because the first step of electrolytes soaking. I’ll let Rajes add on to what I’m saying because it’s very important on how you’re forming the like you know the how the formation happens and stuff. uh but that pressure is needed because you’re trying to create a negative pressure right through vacuum and then uh you purge it so that it’s only nitrogen environment and you increase the pressure so that there is more absorption within the electrodes right what happens is you can still send it also if you have more free electrolyte what happens is let’s say when I’m trying to do some der process and all it also creates uh unstable environments during my process and hence fume out and all of that so the soaking process is very um important and that correlates directly to the pores that you are talking about and the surface energy of the uh electrode that is again the quality is maintained at the electrode and all of it is tied together in that process. Yeah. U just to about the pressure and the nitrogen right and so you see the um you know there is let’s say around 20 25% of posity let’s say inside this right so that means actually those pores are available to fill the electrolyte now if you see you know if you uh touch this uh you know jelly roll you see this too tight right now how you basically push the electrolyte inside to push the electrolyte to all parts of the electrode you definitely need some kind of a pressure cycle. Right? Now coming to the nitrogen, nitrogen is very important because um uh two things um one is the uh as far as the electrolyte is concerned. The biggest enemy of electrolyte is moisture. Moisture right. So you you cannot afford any moisture with electrolyte because u electrolyte have something called as uh LIPF6 which is uh where you have the PF6 and if you have moisture which is nothing but H2O. These two guys will react. Once they react then they form HF. Now to simply say for almost all the chemists are afraid of HF because you know HF can one drop of HF can even eat your phone right? So now you you just imagine uh moisture goes inside the cell and then the moisture reacts with LIPF6 and it forms HF. It is too strong. It will start actually reacting with all your parts inside. Right? So it is extremely important to keep the moisture content as minimum as possible across the process. You must have seen right in everywhere it is dry rooms and uh this is one of the critical process where we don’t need any risk of blowing any moisture inside. So that’s why we do it on a nitrogen kind and the conditions of dry room is actually more stringent in electrolyte filling. It’s the humidity percentage is even lower. Okay. Yes. So I was talking to this folks this mandal which is in between. Huh. Uh-huh. That is someone said it’s not done first like it’s not wrapped around the mantle. The mantle goes last. We should not discuss that, right? Let’s not discuss that. It’s an IP. Yeah, it’s a very critical. We would not like to discuss this part. Fine. That is fine. [laughter] It is an IP thing. So, we will let’s keep this out of Okay. Yeah. I was my next question was going to be how small can the mandal in theory be? Like is that something you aim for like how small because it’s it’s taking up space, right? It’s uh it’s not I mean that mandrel is just uh even if you don’t have this space is still needed. Okay. Because uh the winding itself is uh doing that and then we put that uh tube inside. Yeah. So you know there are multiple reasons right you know. So one is the uh if you are winding such a bigger rolls for 18650 these were these were very small uh you know mantrils right and uh and then point is like during the 18650 the uh winding force was not uh you know that high so it was little bit loose uh electrodes okay but here if you see the you know as everyone is targeting for very high energy density you need to pack as much as possible so you need a you need a stable mandril to hold this uh the big road. Uh another point is uh you cannot you you don’t also want to have very small curvature at the center of the cell because in small curvatures the biggest challenge is um lithium plating. So uh during the charging and discharging process right you know uh the there is something which we need to basically control is the uh n byp ratio we typically call as which is negative to positive ratio uh which is nothing but let’s say 10 lithium is coming from uh cathode. I want at least 10 or 11 sides on the anode to receive that lithium. Now you just imagine a situation where I have only eight sides available for receiving the lithium. Then what happens to the other two lithium? That lithium will start metalizing. Metallizing is nothing but it will form dendrites. Okay. So these dendrites are really really you know dangerous guys. So if you have typically very you know short curvature uh ma managing the nip is also quite challenging. So that’s how you basically you know whatever we have right now is completely based on a design thought process. Okay. It’s not structural. Is it structural? It also helps you in certain structural aspects. But of course uh multiple uh you know it’s it’s like I’m doing this versus folding it there is more strain electrodes can come out that is a different problem. Okay. Okay. So it’s an optimized uh you know structure. Okay. Now I think we are done. The cell is made at least the jelly roll is made. I learned that this caps this negative cap on top and the the positive one is uh imported. I again it’s one of those you know things that seems simple but will not be. What is the complex part of a cap? Um again it’s the same ecosystem we talked about like for graphite right it’s it’s not like we cannot do this we tried we are still working with the local suppliers also uh because now we have uh local electronics manufacturing and then there is aerospace all these industries there it’s specific to battery they are not able to meet the specifications when we launched this product right and we were like 3 4 years before than the others right so now as we are going to the next generation we are starting to localize these as well But that capability that ecosystem today is not there. It’s only because we are our tolerances are very tight including the every curvature every angle every diameter inner diameter outer diameter the micron level is like at point uh less than less than.1 mm to many places and that accuracy at this scale because I need like million cans more than million cans a month at this scale at this accuracy right now it’s not available in India that’s why we have to import right because people say I mean People will look at this and be like, you know, if soda cans can be made, why can’t this outer shell be made? Why can’t this stainless steel be made? But then [laughter] the details here, like you said, uh hitting the spec is the important and and that’s what it’s about for for us, quality first and quality comes with consistency, right? We know that we’ve got some we’ve got capability in this country to de to develop. We will work with suppliers to continue to to develop. We’ll do that in parallel but definitely start with this quality first because the dimensional quality of the mechanical can is extremely important as you go through every process in the factory here and you might have seen in the line we had helium leak tests and all right so essentially this whole can is hermetically sealed where even we do helium test in many process to make sure that even a atom as small as helium cannot go through the crevices of this thing right now we if we don’t have that accuracy we start failing for those and that means Means electrolyte can come out and hence cell is not safe. So that’s what so every one of this gets checked here when it comes in. So yeah be and as well as yes through the entire process right. So as Bella said you know so it’s again qualification on the way in and through the entire process it gets checked. Yes. So there will be an AQC incoming quality check. Uh so that will be sample basis and then once the parts moving into the assembly line there are cameras to cameras to check the auto. So in C2 as well as IQ correct yes okay interesting uh yeah I I think the cell is made now in a virtual cell is made now. Now now let’s come to form factors. M why did you like when you all were starting why did you all decide on a cylindrical cell what was the decision making process like you know that we this is easier or uh established like the decision tree for choosing a cylindric so so so automotive application right especially for a um uh for a two-heer application right and when you are uh trying to look for uh multiple variants right the easiest opt option is actually cylindrical cell because u let’s say you know you want you have to produce 4 kow battery pack 3 kow battery pack and two 2 kow battery pack at the same line uh if you go for a prismatic cell then you will definitely have a bottleneck because um uh let’s say prismatic cell is coming with uh 70 ah uh then um you know if you try to remove one parallel you will not ma mix and match is quite difficult using a prismatic cell, right? So, typically for a two-heer application, if you are really looking for a product portfolio, the best option is actually to go with the you know cylindrical cell. So, you can you you you don’t need to have multiple lines, single line, you know, you can produce the battery pack uh without any uh issue. Second uh thing is the uh the performance wise, right? Um uh especially the uh cylindrical cells uh in terms of the uh temperature uh based uh performance- wise you can still give a lot of u you know gaps in between the cells because you know the cells are not you know attached to each other so there will be gap uh you know these gaps are quite sufficient to uh control the thermal uh uh you know thermal related I I can’t very specifically say what what what thermal but uh many thermal related uh uh you know issues. Okay. Yeah. Okay. I’ll uh before okay we’ll keep the last part for this uh form factors. One thing I was while researching found that there’s a whole uh thing for thermal thermal runaway engineering basically how if there is a short how the vent would how it would vent from where it would vent and from where it would so I would guess this is a part of this cell and uh yes again some modeling must yeah so see the you know if you [clears throat] oh okay so if you see this cell you know the vent is actually here you know there is uh uh thin uh scoring. Uh right. Um now uh we do a lot of simulation uh and also you know machine learning based uh studies to um uh identify what should be the best um you know venting uh pressure to give for a cell. So there are certain thumb rules. Uh based on those thumb rules uh we basically create the vent here. Now typically the cell is tipping uh let let’s say sitting like this or sitting like this uh this vent area will be so when you design a battery pack you basically uh you know keep this vent area uh you know a little far I mean like you you especially you are uh what is that called TCH BCH you know the the holders right you the holders will have this area now when vending happens only this uh vent will open right and then you will have a channel through You basically take the you know so coming into the final design you know design goes through uh lot of simulation mechanical simulation and then uh definitely uh parts testing uh you know you may work with like 20 30 micron difference right you know so 20 30 micron is actually can make uh uh difference in venting right now this is a good reason for why the caps need to be a very tight even I think in our pack it’s kept like this right so that the vent out correct correct so because we have an LH and RH pack in the scooter it’s yeah vending out so that if it’s like this it’s hits this also right so yeah so there is a channel through which actually your you know vending pressure will be taken up okay let’s let’s talk about the sales now I think uh we’ll wrap it up on this uh why 4680 because I don’t know intuitively It feels like the bigger the cell uh the lesser packing efficiency you’ll have more gaps between the cell versus a smaller cells. So why 46 80? Yeah actually you should be pack 2170. That’s so see the thing is even though we talking about this you see technically this is probably three times the size but this is actually holding five times the energy. It’s 5 to1 ratio. So think of it like that. So now in our packs uh we might have in hundreds of these uh let’s say

Yeah that’s all right but uh it is less than Yeah. You want to explain that it’s less than 50 for Yeah that’s right. So in a 4 kW pack 4 kilow pack you’ll have about 220 of these. Okay where you only have 56 of these. Yeah. So so that’s that ratio that we just talked about you know. So it’s very important that why this size again I’ll say it’s more energy in a smaller um I’ll call it in a smaller size that goes makes the product lighter which then gives more range to the customer. It’s as simple as it gets. You’ll see this form factor will change with time but the change will just be in height. Yeah the 4 and 5. Yeah that’s right. Correct. Yeah. So uh well you know in the beginning we said right you know in the same uh specification same battery pack the the same volume uh so we can uh actually uh pack 20% more energy so our products today it’s all public like so this is 4 kW at the max with this 4.5 4.5 with a 21700 if I put these in there 9.1 yeah and what is in the bike that’s 9.1 9.1 Yeah. 4.5 in our in our Roadster product. So 21700 cells. Maximum I can pack in there. 4.5. Put these in there. I can get 9.1 kw hours. 9.1 kW. Wow. Okay. Yeah. So I mean let’s come to the specs. Uh energy density of your NMC versus energy density density of your LFP if you can tell spell the numbers and the C rating as well. I mean it’s a very and it’s available in the you know public domain also 275 water per kilogram energy densities for our NMC LFP I can’t uh you know you know tell you the number now uh because you know once the you know uh certificate comes like you know uh uh then you will easily get we are on the road map there okay uh let me think of my last question maybe [laughter] good yeah I think I’ll talk about the spec what is the C rating of this like I’m thinking from a drone perspective uh I’m always checking how how much uh because it’s important right we the requirement there is having a burst energy like lot of energy suddenly if I throttle it up what does something like this have a C rating um see again this is made for an automotive application right you know uh uh let’s say u you know uh whatever is required for the let’s say a 12 kow motor right you know uh you can say that like you know 3C is uh something which is this is 3C batteries typically all the energy storage uh sorry uh automotive applications uh typically 3C batteries um we uh you know we also have something which is getting ready for the you know high C rate applications okay uh you know drone application which is also getting uh ready soon uh which is very specific to let’s say whatever you are 8C requirement or 12C requirement yeah though I mean the only thing issue with this is it’s uh heavy like I if I can’t build a 6S pack with this the drone the battery will be heavier than the I mean it’s a big drone it’s a different from hobby hobby perspective small so the only point is like you know you you you can still build a 6S but it will be 1 P yes 6S 1 P will be what is the weight of one maybe 300 g I guess yeah approximately yes so you can use basically for the bigger to write you know at least delivery 10 15 kg of uh payload you can definitely use it. Okay. It was very knowledgeable. I loved it. I hope you all enjoyed it as much. It was very good questions actually. I think I in the last I think you had one hour tour there. You had gone really deep. Looks like [laughter] you can come join us if no I I I read everything about all the process before I came in. I made sure to read all these papers involved whatever was possible this unwinding winding uh but I mean we could still have spoken for 3 4 hours actually there was enough material for that uh thank you so Thank you. Thank you.