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So, based on what we have studied so far, what are the most important factors in the battery design? Let's go through them one by one. First thing is the cost. First and foremost, price is very important and critical. The cheaper the battery can be produced while maintaining performance, and the more competitive it is becoming in the market. Second thing is energy density and power density.

Ideally, we want batteries that can store more energy, weight, or the volume, and also deliver that energy quickly when needed. Safety is one of the most important considerations as batteries are increasing using high-power applications like electric vehicles, preventing overheating, fires, and explosions are essential. And then cycle life.

Already we know that a good battery must induce many charge and discharge cycles while maintaining its performance. Long cycle life ensures cost effectiveness and real life over time. And then some temperatures, environmentally or the operation temperature is very important. Already we know that with the global climate change, batteries are expected to operate reliably under the more extreme temperature variations, designing cells that can withstand heat.

or code is becoming increasingly important and then productivities AI based monitoring or diagnostics so you know the with the rise of the smart technology AI can be used to predict battery health and detect the potential safety issues before there occurs this type of the protective maintenance will become a important feature of the future and adjust to the system and

then recyclabilities. Finally recycling is critical. Although the legitimate batteries are now used on the massive scale, the recycling remains difficult and efficient. Strengthening the research and technology in the field of battery cycling is urgent to ensure sustainability and reduce environmental impact. So in summary, ideal

battery must strike the balance between low cost, high performance and high safety, low life and the environmental adaptability, smart monitoring and recyclability. Only by addressing all of these batteries can rebuild the battery of the future.

Now let's look more closely at the design direction of the modern the battery focusing on each of three major components anode, cathode and electrolyte anode is negative electrode traditionally the graphite like here has been dominant on the material because it is inexpensive stable and reliable however its capacity is very low is just

372 mAh per gram. To go beyond this remit, researchers are exploring the silicon-based anode. The silicon can store near the 10 times of the the lithiums compared to the graphite offering the much higher capacity. But then the challenge is the silicon under the huge

volume that changes expansion during the cycling which causes mechanical regression of full cycling light. But then ideally the ideal anode is the lithium metal anode but the lithium metal anode also has a lot of the challenges like as lithium dendrite goes or some the reactivity. Second thing is the cathode we call the positive electrode.

As we discussed earlier, commercial capsules are mostly intercalation models.

So the mostly the transition metal oxide like as NMC, LFP, NCA, LCO. NMC means nickel mangane cobalt oxide, LFP, lithium, iron, phosphate, NCA, lithium, nickel, cobalt, aluminium, and LCO, lithium, cobalt oxide. The main focus of the cathode is the increased energy density from these kinds of transition metal oxide to the increased energy density.

the maintaining also the safety and cycling life is very important so for example nickel reach the ray of oxide like this or we have a we know that NMC series 811 or 532 or some sometimes is the nickel over the 97% things these kinds of high nickel decathode much for years

are being developed to achieve higher capacity but they suffer from thermal instability and poor safety. On the other hand, LFP is very safe and low cost but its evidence is limited as rigid landing or doping strategies such as adding manganese are exposed to improve performance while keeping them manageable. Looking ahead, the next generation is the sulfur conversion type of the cart foot. Made unlocked a much higher 30 degree capacity but they still face the challenge of the stability and

some efficiency. Third is electrolyte. Electrolyte is the medium that allows the liquid ions. So moving here between the anode and cathode. The liquid electrolyte system we use today are effective about rates concerned about some fire, accident or wreckage.

So current research is moving toward the solid state electrolyte, which can dramatically improve the safety by eliminating flammable liquid. But then some solid state electrolyte, sometimes there are some problems, like contact or ionic conductivity or the several things. So another the option is the polymer electrolyte or

gel polymer electrolyte that is the another some the good candidate for the electrolyte gel polymer electrolyte there looks like some the middle stage the liquid electrolyte and the solid state electrolyte so they have some a lot of the advantage so that means uh why do we need to to study polymer.

the battery area. So let's look at the in detail in the castled material. First thing is the LFP castled. The LFP battery is using the lithium-ion phosphate while the NMC battery inflows in the combination nickel-mangan-cobalt. The key difference lies in their atomic structure and

LFP features the olivine structure which is quite stable. The NMC uses a railed structure that allows for high energy density but can be less stable. The olivine structure in the NMC for the specific O-Henzyment atoms that resembles the mineral olivine

This structure creates strong bond between the I1-phosphorus-oxygen atoms, making its energy stable. In contrast, NMC batteries have a wired structure, where the nickel, manganese, and cobalt atoms are the range-distinct layer. NMC-chain allows the lid to move more freely like this one freely.

between the layer during the charging discharging so in the simple terms imagine a step of the neatly arranged seat of the paper like this one this can get the various arrangement in the fast movement of the lithium ions which have to deliver high energy density and the better performance however this structure is less stable compared to olivine

some private which is why NMC battery requires more advanced safety management system. Currently, NMC battery dominance in the global market with the share of over 60% while our LF battery account for maximum 30%. However, the LF-based battery market is shifting rapidly because of...

and safety. So I think some students watch the TV news or some the newspaper. Samsung and LG or the SK is a Korean based company is developing the new LF car suit for the cheaper batteries. So which chemistry the popular battery have? Most popular home battery system currently on the market feature LFP chemistry. This includes the well-known brands like

like a lot of things, the FOX energy storage system, the alpha energy storage system. The notable exception is Tesla. The power to Tesla previous generation's home battery use, an MC cell. However, with the introduction of power 3, Tesla is rumored to have a significant shift to LFP chemistry. and also already the Chinese

Tesla. Some models they use LFP systems. In my memory, the standard range of Model 3 and Model Y vehicles have a LFP battery in the many markets. So there are a lot of things. Definitely LFP is the stable and the cheaper compared to the NMC. However, the NMC has a more high energy density.

So that is the big difference in things. So let's consider the four-packed cathode. Which cathode is perfect? The perfect cathode material would satisfy all the requirements at once. So high capacity, high energy density, low cost, and high safety.

long life like kinds of things is very important. However, in practice it is extremely difficult to meet all of these kinds of creatives in a single material. This is why many studies focusing on the turning transition metal oxide series by introducing different elements to compensate for the data should come in. For example, LFP is a TREPT because it is

very cheap and very safe but its main drawback is the raw capacity. So in case of the NCM, this course is good. Not yet. I think at a time is the NCM the raw level of materials. And then with these kinds of the some another strategies is the modifying existing material by partial

substitution or doping like as LMFP is one of the example the LFP with the manganese materials to improve the battery some cycling the safety and cost effect up to now the most of the lithium-ion battery we use the rely on intercalation material in this material I introduce that lithium-ion is moving here and

the move out whole structure during the charge and discharging so example is including the LCO is the first little man battery is more the battery so LMO or NFP and the NMC everything's intercollation material have a clear advantage stable reversible and good cycle life bottom still they have a some critical the limitation the number of lithium ion that can be insert and extract is restricted by the host structure

That means the daily car capacity and energy density is the capped. So we know these kinds of common intercalation cathode have this level of the battery capacity. So this is the reason which is needed the conversion type of cathode.

Conversion reactions, the cathode undergo drastically chemical transformation when the lithium reacts with these kinds of components. For example, sulfur with the lithiums can change a lot of things.

final form. They have a new covalent bond in here. So there are some the convergent type cathode has the pros and cons. One is the advantage of the convergent height cathode is the much higher theoretical capacity. In case of the sulfur, theoretical capacity is 1675 milliampere of gram. It

I think seven or eight times higher than the intercalation type and potentially this low cost is very cheap usually so far but still there are some the challenge like it's volume expansion or volume changes so that means mechanical instable and the full cycle life so for the the future direction of these kinds of the Tafel research is clear if

improve the stability or conversion material. So using the nanostructure or composite system, there are many options. Or the coating or doping the system. So if the conversion type is successful, these kinds of the cathode could become a next generation high capacity material that could be the limit of the intercalation

chemistry. So let's recheck the characteristics. Intercalation type, lithium insertion without structure changes. Conversion type is phase transformation. Capacity, definitely. Conversion type is good. Cyclability is good in the intercalation. Conversion type, still there are so many challenges like as volume changes or phase changes. Fast charging, both challenges.

Energy density is really good in case of a convergent type. So which material? Intercollation is transition metal oxide type, lithium cobalt oxide, NMC, NMO, LFP. There is some example. Convergent, sulfur, fluoride oxide, sulfide. There are many options. So next is about the anode material. The anode flies a crucial load in the lithium-ion battery.

by storing and releasing lithium ions. During the operations, lithium ion is moved from the anode through the electrolyte to the cathode, while the electrons traveling on the external conductors connecting the two electrodes. Through this coordinated movement, ions and electrons, electrical energy is generated. Importantly, the anode materials directly affect both charged

charging speed and the lifespan of the battery, the more lithium-ion the anode can store, the longer the battery life span will be. The more easily the anode accepts the lithium-ion, the faster charging can be possible. Therefore, even if the acid can generate a large amount of energy, the overall efficiency is limited.

if the anode cannot properly store and release little ion. This is why the development of the advanced anode material is such an important area of the research. Now let's look at the anode materials. So most commonly made carbon-based material. The one of the example graphite but that is graphite is dominant but then there some the limitation is

the capacity and then second thing is a silicon. Silicon provides a much higher energy density like this one, nearly 10 times that of the graphite but they suffer from the several some issues one is severe the volume expansion during cycling which reduce their cycle life. A common approach is the composite or graphite.

For silicon, the surface interfacial coatings, some other material or some nano size structure of the silicon is one of the examples. Ultimately, lithium metal is the most ideal anode because it has the highest theoretical capacity. But the lithium metal faces a serious challenge like dendrites.

what is dendrite is the lithium metals. When the lithium ion is deposited here, lithium and the lithiums, it looks like the tree is quite the nature's property and characteristics. And then the lithium can react with the nitrogen and oxygen. And then the lithiums, a lot of the materials, so that means they have a high reactivity.

Another thing is the price is very expensive. For this reason, the some modern the battery research continues focusing on the improving anody material finding the some balance between the energy density cycle, life, safety, cost. Next is the electrolyte. You know the electrolyte is very important like as the the

medium the rithium ion is moving the cathode to anode, anode to the cathode. So usually the electrolyte consists of the rithium salt and the organic solvent sometimes additive. Additive is played of the some improving the stability or the some primabilities, a lot of things.

The Ritium salt is severe as a pathway for the Ritium ion, the movement. In other words, the Ritium ion dissolves in the salt, allowing them to travel freely. The most commonly used in Ritium salt in the battery is LiPF6. It's very old chemistry and it's known as general proposal as electrolyte.

So it's the excellent ionic conductivity, solubility in the solvent and the chemical stability is really good. And it is widely used in the small IT device such as smartphone. Bottom sometimes is sometimes it has some problem with the little metals or other material. They make the acid hydrogen fluoride and these kinds of hydrogen fluoride in the system attack the NMC or LCO.

LFP. So you know the HF is the exit. Exit cannot take the metallic structure. So like nickel ions, manganese ion, cobalt ion is dissolved in the electrolyte system. So that means we lose the capacity. So another the option is the lithium-sort. LITFSI, LIFSI or LIDFOV. A lot of the options for the

battery, rich in salt. So this is LIFSI is quite common for the battery the stability and ionic conductivity. But on the price is quite high. And second thing is organic solvent. Organic solvent have dissolved rich in ion and salt. The form that performs this rule, the solvent needed to high permittivity to effectively separate the ion compound and the low viscosity or smooth movement of the lithium ion. So we can imagine some

water if either some kinds of the medium is loops is quite the viscosity is low it will be half for the lithium ion the transport third is additive I already introduced the additive additive is very small but below usually below the 5% to enhance battery life span improve stability and optimize the performance

one of the some good the additive there are many types of liquid type or some the solid type liquid type is the fluorine ethylene carbonate fec is one of the famous the additive and the solid type lithium nitrate is one of the the famous rhythm source i think that these kinds of the something just some the knowledge and just information you don't need to memorize all of the things but the important things is the electrolyte consists of

the lithium-sort organic solvent and sometimes additive. So for the next generation the electrolyte system from the liquid electrolyte for the safety we can consider solid state electrolyte or quasi solid state electrolyte. One of the examples is gel polymer electrolytes.

we can know this kind of collector is very important for the next generation the battery next is the part is about the fabrication to fabricate a lithium-ion battery they represent the four step manufacturing electrode and then cell assembly formation

Packing. First electrode manufacturing. So making a cathode and anode of the battery. There is a four step. Mixing, coatings, roll pressings, and slating and the nottings. Mixing means just the mix together the cathode or anode material and solvent and

the conductive agent or polymer binder in the maker slurry like as intermediate product at this stage binder are added to enhance adhesion between the active material particles and then the coating the combative cathode and anode slurry are thinly coated like this one onto the aluminum foil or the copper foil so aluminum foil usually used for the

copper foil is anode. So in this process, the binder also is evenly dispersed onto the electrode for the high performance and the long life of the battery. Roll flattings using the calendaring tools. When the coating is done, electrodes go through the two big rolls and get evenly flattened. The electrode surface bonds to optimize the battery allowing the lithium ion to travel more easily. As a result,

the output and the performance battery improve slitting and no shinks just like as we can think about that just cut punch cutting to require side to feed for the battery you know sometimes we need the the soccer type cathode sometimes we need like this scale type the electron material second thing is the

cell assembly forming the battery shape. So there are many types of coins, pouches, cylinder, box type. A lot of things of the battery saw. In the cell assembly, battery type shape as we know that. The order of the manufacturing process differs depending on the shape.

Each battery maker employ their different technology. Parch type is the first mono cell is manufactured as a basic unit for battery production. Then a cell stack is assembled using ramination and stacking. Next, the pouch film is compressed to form the pouch case consisting of an electric pocket and a gas pocket. This is quite a very complex one of the things.

Step 3 is the formation. Formation means activation. So activating a battery with electrical energy and stabilizing it. Formation is the process consists of repeated aging, charging, discharging. First, the battery is good at room temperature. So the electrolyte can be used.

from it into the cathode and anode that means aging when the electrolyte soaked into the inside of the battery and the ions move smoothly between the cathode and the anode the battery is charged into a certain levels the formation process is a little bit different by the battery manufacturer number four is the packing packing process is forming a module to feed the models

So depending on the module, sometimes battery pack design is totally different. So finally the complete modules are placed into the battery pack and connected in the module to module configurations. And finally the pack is assembled. So summary of the fabric weight. Supposedly making electrode and the punching and the assembled cell.

and the formation step for the activating the battery system and the inspection and finally packing there is one of the the video so it's about the fabricate the battery the technologies the you can see the some little bit the pilot scale of the fabrication of the electrode

Even the electrodes in the process, there are many steps like throwaway mixing, coating, drying, or notching, the punching, a lot of the inspection including. So there is very important step for the battery because the electrode, if the electrode is not good, definitely battery performance is not good. And then already I introduced that there are three main types of configurations that stand out among the manufacturers. First, prismatic cell which are characterized by their packing capacity.

to their configuration by stack layer. Second is the pouch cell whose main feature lies in the lightweight thanks to their aluminum coatings. Third is a cylindrical cell so it's kind of design so and the stability are the easily scalable for mass productions. These three options are currently leading the market especially first two like the Fritzmatik and the Parchies.

According to the study by the Ardonix in 2020, the market share for the battery sector was distributed as 40% prismatic cell and 35% pouch cell and 10% cylindrical cell, becoming the production figure of the world's major manufacturer. This variety in the market is due to the advantage and disadvantage offered by each battery format.

So a lot of things like this advantage of prismatic cell, high mechanical stability, high packing density, like a cylindrical cell also, high mechanical stability, generally low cost, but in case of pouches cells, it's lower mechanical stability, but they have a high packing density. So depending on the application of the battery, so battery manufacturer choose the suitable, the form factor.

So considering various the some side format as you can be seen there is no clear some the best the structure in the industry on what the format might shape the future of battery technologies as happening the other aspects of the industry different manufacturers and end-users are batting on the different customized alternatives try to develop the best solution for their needs and challenging let's look at some safer things rgcam button means change the name

LG energy solutions so they format is cylindrical and the pouch and also the LG has a special some design the jelly rolls some like these kinds of jelly rolls of structure Samsung is a cylindrical prismatic SK's pouch is CATL prismatic but on these CATL is

making a different type of the format. Panasonic is the cylinder occurs. I think this is quite popular because of the Tesla, the electric vehicles and North world is prismatic but unfortunately North world is the disappears soon because of the bankrupt in Sweden and the backer is pouch, guthion and prismati.

I think this name is not famous previously but you know because of the Mercedes Vans so you know in the Incheon, Cheong La apartment the fire accidents from the electric vehicles at the time the electric vehicle of the Mercedes Vans they have the installed the policies the battery cells

That is the end of these chapters. So in these chapters we learned about the basics and the basics of the electrochemicals from the idea for the lithium-ion batteries. So we covered a lot of things. But I think it's not needed to memorize all of things. But one of the important thing is that I can't remember the whole thing.

recommend the memorize some like is what is the main component of the lithium-ion battery so you can answer the anode cathode separator led light that is the the main option and if you're okay and available i would like to check the which material is the anode which material or the cathode so

So what is the separator? What is the electrolyte? The basic concept is very important for understanding the battery. Moreover, in the first sections, we learned about a lot of things about the battery characteristics, like this discharging curve, what is the C rate? This kind of thing is very, very hard to understand and study the battery.

so if we if you know these kinds of things finally we can understand and we can evaluate the battery oh this battery is really good and stable or is this battery might have is good energy density so that is the end of chapter and thank you very much