Mettler-Toledo International Inc. (MTD) Earnings Call Transcript & Summary

All right. Well, welcome, everybody. We will get started here in a few minutes. Feel free to put your questions into the chat throughout the webinar session. Just a reminder that we will have a live demonstration of our C30S titrator, with Karl Fischer InMotion Oven at the end. And so please stick around for that. As we get everybody logged in here, we'll start this in just a couple of minutes. Thanks.

Hello, and welcome to Mettler Toledo's live webinar. My name is Renee Doran, and I'm a lab market specialist here at Mettler Toledo. To get the most out of today's webinar. Don't worry if you miss anything, we will have it on-demand on our website shortly after the live session. Participate in polls. We would love to hear your perspective and also there will be a survey at the end of the webinar. Utilize the chat function, enter your questions throughout the webinar. If you're having technical issues, go ahead and reload your browser first to establish a new connection. We offer a broad range of solutions across our customers' value chain. This will help you to streamline your processes, enhance productivity, reach compliance with regulatory requirements and optimize costs and reduce waste. And now on to the webinar.

Thank you all for coming to our webinar today. We're going to talk about analytical instrumentation solutions for battery characterization, production and testing. We will hear from Dr. Brian Turner, who will discuss material characterization by thermal analysis; Jen Butler, who will discuss electrolyte analysis by titration; and myself, Dr. Danielle Kimmel, who will provide a brief introduction to batteries. Historically speaking, the first true battery is the voltaic pile, which was invented by Alessandro Volta in 1800. A few decades later, in 1860, Gaston Plante invented the first rechargeable battery, the lead-acid battery. The lead-acid battery is still used today as ignition power sources for automobiles. Thomas Edison developed a robust nickel iron battery in 1910, and it was primarily used for standby power applications until it was discontinued in the 1970s. In the 1960s, nickel-metal hydride and nickel-cadmium batteries became popular for powering handheld devices as a substitute for alkaline batteries. And in the 1970s, lithium-ion batteries were first invented and are widely used today. In fact, the invention of lithium-ion batteries are: John B. Goodenough, M. Stanley Whittingham and Akira Yoshino, win 2019 Nobel Prize in chemistry. Today, lithium-ion batteries power the majority of our portable electronics, being lightweight, charging rapidly, having a high energy density and a long life span, make lithium-ion batteries ideal for electric vehicle applications. If we take a look at the annual growth of lithium-ion batteries and main market segments from 2010 to 2017, we see that the greatest increase is due to the electric vehicle segment, analytical tools to ensure proper battery function are critical for this market segment to ensure consumer safety on the road. The working principle of the lithium-ion batteries intercalation mechanism can be seen in this schematic. The battery consists of a positive electrode, the cathode, a negative electrode, the anode, and electrolytic solution. When the cell is charging the cathode, which is usually composed of lithium cobalt oxide is oxidized, and the anode, which is usually composed of graphite is reduced. When the cell is discharging, the reverse occurs. The lithium-ions do not partake in the overall electrochemical reaction and remain in their oxidized state. Let's take a deeper look at the composition of each part of the battery. First, we have the anode, which enables current to flow through the external circuit while allowing reversible absorption emissions of lithium ions released from the cathode. Next, we have the cathode, which determines the capacity and voltage of lithium-ion batteries. The separator ensures the anode and cathode are kept electrically isolated but is porous enough to allow the electrolyte and lithium ions to pass easily through it. The separators physiochemical properties have a great influence on the performance of the battery. Lastly, we have the electrolyte, which is composed in materials with high ionic conductivity, so that lithium ions can move between the anode and cathode via diffusion. The electrolyte is usually composed of lithium salt, organic solvents and various additives. To analyze these components, I'm going to first turn to Dr. Brian Turner to discuss thermal analysis.

There are numerous opportunities to characterize solid battery materials by thermal analysis. We can utilize the full suite of thermal analysis instrumentation to verify battery components or learn about new materials in the context of research and development. All of these measurements will inform whether a material is suitable for the intended use in a battery. Today, I am going to discuss 4 applications to analyze the 4 main components of lithium-ion batteries, the electrode material, separator, binder and the electrolyte. The first application I'll start with is the analysis of the electrode materials. Using the Mettler-Toledo TGA, we're going to look at cathode thermal stability and how we can monitor reduction of an anode. TGA or thermogravimetric analysis is a technique where a sample is subjected to a controlled heating program and the mass is recorded as a function of time and temperature. The result of mass changes can be correlated with different contents as well as to discuss the stability of a sample. A stable sample fundamentally should not exhibit mass change within the temperature range of the application. Here, we have the data from a TGA experiment on lithium iron phosphate, a cathode component. Lithium iron phosphate loses about 1.1% of its mass at 150-degree Celsius and in the second endothermic decomposition step, 19.9%, up to 800 degrees Celsius. The DSC curve for lithium iron phosphate collected simultaneously also shows 2 small exothermic peaks around 520 and 700 degrees C. Both peaks are not associated with any mass changes in the simultaneously collected TGA curve and are probably due to solid, solid transformations. Based upon the TGA observation, we can see that the cathode material is stable up to 150 degrees Celsius. That is to say the sample does not lose any mass from the DSC spectrum, there are very little peaks in the heat flow curve indicating any sort of physical transformation. The DSC data, higher temperature also yields structural information about the sample at lower temperature, specifically that the sample can reorganize into more stable crystal structures with either more thermal energy or time. Next, we have the data from a TGA experiment on lithium cobalt oxide. Here, we can see that it loses 1.2% in the low temperature range and is stable from there up to about 350 degrees C. From this temperature, the endothermic decomposition of the material takes place in 2 steps. You can see that as a 2-step process by looking at the derivative thermogravimetric curve that's a plot of the rate of mass loss derived directly from the black TGA mass loss curve. And you can see that it has a double peak indicating 2 different processes. We see that the measurement curve provides information about the thermal stability of the sample. They show that lithium iron phosphate from the battery is stable up to 150 degrees C and lithium cobalt oxide from the battery to stable up to 350 degrees C. For comparison, the pure materials were also examined. Both pure materials are stable under inert atmosphere conditions up to 800 degrees C. Using a simple TGA technique, we were able to gauge the thermal stability of 2 cathode materials. The next example has to do with the processing of raw materials and creating the battery anode. The anode lithium-ion battery can be pure graphene. One industrial route to the production of graphene is first conversion of graphite into graphene oxide followed by thermal reduction to graphene. This process can be directly investigated by the TGA DSC instrument. Graphene oxide is hygroscopic, so at low temperature, the first loss that is observed is the evaporation of moisture. The simultaneous DSC signal exhibits an endothermic peak in this region, consistent with loss of moisture. Exothermic elimination of oxygen from the material proceeds in a number of steps. The final loss of oxygen is very slow. This indicates that either higher temperatures or reducing agents such as hydrogen should be used to obtain the pure graphene. In summary, TGA-DSC may be used to study raw materials to elucidate their processing into anode materials. The next example focuses on the electrolyte. Here, we will use 3 types of instrumentation. TGA, which we've previously shown, and now TGA with EGA or evolved gas analysis and also with the DSC or differential scanning calorimetry. These instruments will allow us to learn about the melting temperature of the electrolyte and provide insight into the processes governed by these values as well as the water content of the electrolyte. Evolved gas analysis or EGA refers to the coupling of gas analyzers to the outlet of the TGA furnace to elucidate evolved gas [ ECs ] and aid in their quantification. Differential scanning calorimetry, or DSC measures the enthalpy change in temperature range associated with thermal transition, both transition and without mass change. In this way, DSC is highly complementary to TGA. Let's start with the DSC example. The electrolytic solutions commonly used in commercial lithium batteries consist of organic solvents, lithium salts and some additives. The organic solvents are mainly cyclic carbonates such as propylene carbonate and ethylene carbonate, or chain carbonates, for example, ethyl methyl carbonate and diethyl carbonate. Composition and ratio of these carbonates have been important implications to the cycling stability, energy density and safety of lithium-ion batteries. The DSC curve of the first heating run shows a glass transition near minus 116 degrees C, followed by a broad endothermic melting peak. The melting of the binary mixture leads to partially overlapping endothermic peaks on the DSC curve. Propylene carbonate melts at a lower temperature with a peak at minus 54.6 degree Celsius. The melting enthalpy of the major solvent component amounts to negative 82.69 Joules per gram. The content of this component in the solvent mixture is about 76.6% based on the literature value of 107.97 Joules per gram for the heat of fusion of ethyl methyl carbonate. A battery working with this type of electrolyte can only be charged above 0 degree C. When the electrolyte is in the liquid state, discharging the battery is possible down to slightly lower temperatures. However, the determination of respective minimum temperature is more complex in this case as it would require experiments in isothermal crystallization measured at different temperatures to understand the kinetics of the crystal formation. Next, we're going to look at a promising new electrolyte additive, Lithium bis fluorosulfonyl imide. This electrolyte shows increased conductivity over the more traditionally used lithium hexafluorophosphate. In order to use this electrolyte, this solution should be free of water to prevent the formation of dangerous hydrofluoric acid. If we use TGA coupled to mass spectrometry or TGA-MS, we see that the sample contains water in this case and at higher temperatures, releases hydrofluoric acid as well as diatomic fluorine, which can lead to catastrophic failure of a battery and a dangerous explosion. The next battery component that we can look at with thermal analysis instrumentation is an investigation of the separator, the separator is the porous membrane placed between the electrodes of opposite polarity. It is permeable to ionic flow but prevents electric contact of the electrodes. Here, we will utilize the TGA and TMA to measure thermal stability, purity and thermal expansion. Thermomechanical analysis or TMA, utilizes a quartz measurement device in a tube furnace to obtain micrometer or nanometer scale dimensional changes in materials under very low deformation conditions. Here, we see the TGA curve of the separator, which is a polypropylene film. Decomposition starts at about 380 degrees C and the inflection temperature of this mass loss is around 462 degrees C. After switching from nitrogen to oxygen atmosphere, no further mass loss is observed. Therefore, decomposition occurs in a single step, which is typical for pure polypropylene. Here, the TGA is used to confirm the absence of impurities, which could compromise battery performance. Next, we'll look at expansion of these materials. Polypropylene films undergo catastrophic shrinkage at higher temperatures. Therefore, separator shutdown is a useful safety feature for preventing thermal runaway reactions in lithium-ion batteries. Here, we use the TMA to characterize the shrinkage and melting behavior of the separator membrane. The shrinkage of polypropylene takes place in 2 steps in which different types of crystals are formed. Closure of the porous occurs during the first shrinkage step between 140 degrees and 170 degrees C. The second shrinkage process takes place up to about 175 degree C, at higher temperatures, the sample elongates due to melting. The onset temperature of the first shrinkage at 140 degree C corresponds to maximum application temperature of the separator. In this example, for safety purposes, it is important that the separator shuts down, i.e., closure of porous before the onset of melting. This is confirmed using TMA. The last component that we're going to study with thermal analysis in this presentation is the binder. The binder holds the active material particles within the electrode of the lithium ion battery together and ensures a good connection of electrode and contacts. Binders are usually inert flexible and insoluble in the electrolyte. In recent decades, polyvinylidene fluoride or PVDF, has been a popular choice of binder material for lithium-ion batteries, especially in cathodes. The fluoropolymer produced by the polymerization of vinylidene difluoride, exhibits excellent electrochemical and thermal stability and good adhesion between the current collectors and electrode films. PVDF of high purity is important for providing enhanced battery safety and performance. In this example, we use DSC or differential scanning calorimetry to measure caloric effects. For example, the glass transition in melting, while the decomposition and combustion of PVDF was studied by means of TGA or thermogravimetric analysis. First, we will look at the DSC results for this material. Here, we see the second DSC heating curve of the PVDF sample. PVDF exhibits a glass transition at about minus 40 degrees C in a melting at about 175 degrees C. The enthalpy change at the glass transition is 0.21 Joules per gram Kelvin and the melting enthalpy is 76 Joules per gram. Thermogravimetric analysis shows that PVDF sample was stable at high temperatures. No thermal degradation occurs below about 450 degrees C. In addition, DSC allows for a detailed characterization of key quality control parameters such as the glass transition, melting and crystallinity to assure that materials are consistent. Next, we'll look at the TGA and DSC curves of PVDF. These were measured in the Mettler-Toledo TGA DSC. The sample was first heated to 900 degrees Celsius under inert conditions, thus shown by the black curves. Material decomposes in 1 mass loss step of 80.7%, reaching a maximum rate at 504 degrees Celsius. After pulling the 300 degrees C, the atmosphere was switched from nitrogen to oxygen, which results in the combustion of the carbon additives at about 550 degrees C upon reheating displayed in the red curves to a total amount of 19.6%. The lower part of this figure displays the simultaneous DSC curve under nitrogen up to 450 degrees C. The melting of PVDF is observed at 178 degrees Celsius. Here we have seen how the raw and processed solid components of lithium-ion batteries may be analyzed by thermal analysis instrumentation for their material properties and stability. Our next topic covered by my colleague, Jen Butler, will be analytical chemistry characterization of battery chemicals and solution primarily by titration techniques.

Hi, I'm Jen Butler. I'm an instrument sales specialist for Mettler-Toledo within the analytical chemistry division and based out in Northern California. And today, I'm going to be doing an overview of some common analytical chemistry applications that are often seen within the lithium-ion battery market segment. Specifically, we will discuss water content determination by Karl Fischer titration, some other various titration applications, density determination, softening point. I will also show you some of the weighing applications that we can cover with our balances as well as an overview of the Mettler-Toledo. There are some common QC in production applications of lithium-ion battery materials, and they are as follows on this slide. Please note that each of these applications, we do have an application though, which we would be happy to share with you if you would like some further information. Common applications include the contamination of water using Karl Fischer titration with the InMotion KF accessory, determination of hydrofluoric acid in lithium hexafluorophosphate, also determination of alkali amount and lithium battery materials. Determination of cobalt content, determination of total metal content, determination of manganese, cobalt, nickel, total iron and determination of chloride [indiscernible] content in lithium-iron batteries are amongst the applications that are commonly used within the industry. As you can see here, I have shown some of our analytical chemistry instruments. We have the InMotion KF, which is the oven accessory to our Karl Fisher titrators. The S220 is a compact pH meter, you have titration excellence, density excellence and also [ EUV ] this. Each of these instruments are used in the below measurements that are identified based on the battery components. Cathode materials, we are often looking for lithium carbonate, lithium hydroxide and lithium chloride. This can be done by our titration excellence instruments. Also, cobalt, manganese, nickel and iron can also be determined using the titration excellence. pH measurements can be taken use in the S220, or other benchtops pH excellence meters, water determination of the cathode materials is often done by our C30S Karl Fischer titrator, with our InMotion KF Oven accessory. For the anode materials, bitumen is often measured using our drop in point instruments DP70 and DP90. pH measurements are taken of anode materials as well as water determination using our C30S and InMotion KF. The electrolyte solution is also verified for water content using our C30S. Hydrofluoric acid and chloride content are measured using our titration excellence instruments. Density determination of the electrolyte can be used even with our benchtop density excellence meters or also [indiscernible] APHA of electrolyte measurement is done with our UV Vis instruments. Battery diaphragm is also another one -- that lithium-ion battery production is a critical measurement. Solid content of [ electrophoresis ] affects the coding quality and the electrode performance and too much moisture leads to electrode corrosion due to the electrolyte degradation. Performance will decrease, which lowers capacity and makes charging time longer, and there's also a safety issue of explosion. Water also leads to the formation of aggressive by products such as hydrofluoric acid, which destroys the electrodes in vessel, versus capacity of the battery. Cathode, anode and electrolyte easily absorbed moisture form the air, so it is a critical measurement. Strict control at various points of production is crucial. And as you can see here, the Karl Fischer titrator with the oven accessory can be used at various stages within the production process. The titrator and the oven is photographs below. So you can see that. We've got the titrator on the left and the oven on the right. And the gray tube between the 2 is a heated transfer tube, which will carry the water from the oven to vessel. So as you can see during slurry mixing, manufacturing of the electrode, cell rolling and also the electrolyte filling, our Karl Fischer titration for water determination is a critical analytical analysis needed at each way. Water determination of the solid materials is best measured by gas extraction technique with coulometric Karl Fischer detection. The electrode sheets are cut into small flakes or strips placed into the sample vials and weighed in place on to the InMotion KF oven rack. The mechanism started with 1 click [indiscernible] heats the electron samples to 160 degrees C and a pre-drive stream of nitrogen extracts and carries the vaporized water to the coulometric titration cell where it is detected. Also by Karl Fisher titration is water determination of the electrolyte solution. This is typically done via direct injection of the electrolyte into the Karl Fischer vessel. Measuring the water content in the electrolyte is a little bit more challenging, and it's primarily because the electrolyte has a very low water content, typically below 50 ppm. It is also highly hydrophilic making careful handling very important. The sample container should be closed in a dry atmosphere protected from air humidity by rubber septum and the syringes must be rinse with the dry electrolyte prior to the injection. Next, I want to walk through the principle of the gas-based extraction by Karl Fischer with the InMotion KF Oven accessory. The air pump or gas valves is used to generate the gas flow needed for the analysis. The gas flow is then dry by the gas drying unit, which you can see those 2 small dryers there. Using silica gel and molecular sieve to a water content of about 10 to 20 micrograms per liter to achieve low drift value. And this gas flow is measured by a precise digital gas flow meter, which is regulated within the method itself and is done automatically. The gas flows into the sample vial which is heated by the oven at a specific temperature, which is also dictated by the method and the water is collected, extracted from the sample. The water is then brought into the titrating by a transfer tube where it is titrated by a Karl Fischer titrator, whether it be volumetric and coulometric. But most often times, it is coulometric for this application. Our 3 different sample vial sizes. They have a 5 mL, 10 mL and 20 mL vial sizes. The smaller the vial volume means lower blank values and the lower the blank values this will ensure the most precised and accurate results. As you can see here, listed by each of the vial sizes, the average blank value is listed. The 5 mL and 20 mL vials are only available on our InMotion KF Pro model. Another feature of the InMotion KF Pro model is the temperature scan function. With the temperature scan function, it is possible to find the ideal temperature to heat up a sample in just 1 run, and this will save hours of precious working time. This is done by speeding up the R&D workflow on any unknown samples. For example, you may heat up the sample 2 degrees Celsius per minute and watch the behavior of the sample and how the water comes off. Moving on from Karl Fischer titration. There are other titration applications that are often used within the market. Hydrofluoric acid determination is a very important control index for the lithium hexafluorophosphate electrolyte. High hydrofluoric -- have a great negative impact on the battery capacity, cycle life and even safety. To determine the hydrofluoric acid content in the electrolyte, this is done by an aqueous acid-based titration. Another important measurement is the determination of the alkali content. Due to the requirements of production, it's necessary to detect the content of lithium hydroxide and lithium carbonate in the battery material. Two bases are titrated by acid-based titration. There is also a metal content analysis. And titration is a preferred method to solve the determination of the constant metal content. Single content can be obtained by the method of complex titration and redox titration. Similarly, the total iron content of lithium iron phosphate can be titrated in the sample by needs of redox titration. The lithium hexafluorophosphate electrolyte is not stable during hydrolysis. Traces of water in the electrolyte lead to the formation of hydrofluoric acid, which is considered a battery poison, destroying the electrodes and lowering the capacity. Therefore, the amount of HF in the lithium ion battery electrolyte should be as low as possible. We determined the hydrofluoric acid content in the electrolyte by an aqueous acid-based titration with potential metric indication. Determining the alkali content. The volume of the first equivalent point up to pH 7.5 includes of the hydroxide and the carbonate ions. The second equivalent point at about 4.5 pH corresponds to the hydrogen carbonate ion content. Another important measurement is density. The reagent liquid used in the production of the lithium batteries in the lithium hexafluorophosphate electrolyte need to be measured for the density to reflect the quality of the product. The Mettler-Toledo digital density meters require very few samples to complete the measurement. They have an accurate temperature control on the density excellence or attempt in compensation option with our portable handheld Densito. We demonstrate fast measurements and good repeatability, and there also is a built-in automatic results verification analysis so you can set your limits, and the results will show and pass or fail. Together with connectivity in Karl Fischer titration, density determinations are carried out to characterize the electrolytes. Softening point of pitch. Pitch is a shiny black residue obtained by distillation of coal tar, which is produced as a byproduct during the manufacturing of metallurgic coke. It is used as a base for coatings and paint and roofing and painting and most applicable to this group as a binder of the manufacturing of carbonate graphite electrodes. Its solid at room temperature and shows a softening point instead of a definitive melting point temperature. The Mettler-Toledo DP70 or DP90 is able to carry out this method according to ISO-5940-2 for pitch for electrodes. There is a built-in camera, which records the softening determination of simultaneous samples. Accurate weighing of your samples in each step of the process of the lithium battery production is critically important. As you can see here from this list, there are many applications to use Mettler-Toledo balances, whether it's in the anode, cathode, separator, electrolyte or in the raw materials. Regardless of the test, whether it's purity thermal stability, water content or formulations, there is an analytical micro or ultramicro balance that is applicable to each and every application you see here. In summary, this is an overview of the applications that Mettler-Toledo has instrumentation to help you with. Between Dr. Turner and myself, we have discussed weighing, pH re-connectivity, titration and various material characterization products. In addition to these lines of instruments, we also have an AutoChem group, a Pro group, which is our in-line group in industrial, which can help with industrial weighing applications. So from start to finish, Mettler-Toledo has recovered. We have many resources available to you. Mettler-Toledo has a lithium-ion battery landing page. If you google lithium-Ion battery production on Mettler-Toledo's website, you will be taken to this landing page where you can then scroll down and find your area of interest. All of our white papers and application notes are housed here as well as a wealth of other information. If you have further questions, do not hesitate to reach out to your local Mettler-Toledo representative. Thank you.

As Jen just mentioned, Mettler-Toledo provides elegant solutions across the entire battery value chain from research and development, to manufacturing, disbursement and customer usage. We hope that you have enjoyed learning more about the Mettler-Toledo solutions for battery characterization, production and testing. Thank you to both Brian and Jen for sharing their expertise.