Backgrounds:In recent years, due to issues such as nuclear power plants, increased awareness of environmental issues, and electricity liberalization, we have begun to hear more and more frequently about how to save electricity and other power-related information. Among them, it is a typical term often seen in electricity-related fields.What is a Virtual Power Plant (VPP)?Virtual power plant (VPP) refers to power generation equipment such as renewable energy and fuel cells, storage battery equipment that efficiently stores and uses electricity, and consumers (demanders) such as homes and factories that consume electricity, and refers to centralized control, specific areas. It can be said to be a smart city concept that expands the scale of so-called smart homes. It is called a virtual power plant because it is like a virtual power plant in which all equipment, including power generation and storage, is controlled within a certain area.What are the benefits of VPP?Basically the same concept as the smart home (installing a household battery, etc.), and has the following advantages. For example, if electricity demand exceeds supply during a time when everyone uses a lot of electricity, such as during the day, demand response can be used to request power savings and reduce demand. On the other hand, during periods of abundant power supply, the generated power can be used more efficiently by storing it in storage batteries in the area, so that too much power is not wasted.Moreover, what makes it more attractive than smart homes is that it can introduce renewable energy sources, such as solar power plants and wind power plants, which can only be introduced using a certain amount of land, making it more renewable.Similarly, by integrating battery equipment over a considerable area of land, it can be said that it is conducive to improving the efficiency of electricity storage and taking safety measures in advance. Currently, VPP is in the early stages of demonstration testing, so there are many challenges to its widespread use, but it can be said that VPP is very attractive because of its potential to contribute to the environment and bring savings.

The Basic Science Behind Lithium-Ion Batteries: How They WorkWhat is the mechanism of lithium-ion battery?? Understanding its nitty-gritty enables you to assess the value of this rechargeable battery to various industries and applications. This article provides a comprehensive discussion of the science behind its operation.The Concept of Lithium-Ion BatteryA lithium-ion battery, famously known as Li-ion, works on an electrochemical reaction that involves lithium ions moving from one electrode or terminal to the other. It stores energy by moving these ions from a positive electrode called cathode to the negative anode during charging and transforming energy back to the cathode when discharging. The electrolyte, a li-ion conductor, is responsible for providing the pathway for these ion movements.The Three Major Components of Lithium-Ion BatteryLi-ion batteries have three primary components that contribute to their energy storage function: the cathode, anode, and electrolyte. The cathode is typically made of metal oxides, while the anode is typically made of carbon. The electrolyte, which is typically a lithium salt in an organic solvent, acts as the mediator of the ion transportation process.The Electrochemical Mechanism of Lithium-Ion BatteryDuring the charging process, lithium-ion batteries absorb ions from the cathode, moving them through the electrolyte, and depositing them into the anode. When the discharging process begins, these ions move in the opposite direction, from anode to cathode, producing an electrical current as they pass through an external circuit. The reaction between lithium ions and the active materials in each electrode during charging and discharge enables the efficient transfer of energy from one electrode to the other.The Role of Electrolyte in Lithium-Ion Battery technologyThe electrolyte in a lithium-ion battery is critical in determining the battery's performance, safety, and stability. The highest-performing electrolytes contain salts that have minimal reactivity with the active materials. The electrolytes also have a high dielectric constant to resist electrical breakdown and maintain high-ion conductivity to facilitate ion transport between the electrodes.The Importance of Cathode Material in Lithium Ion BatteryOne of the essential considerations when selecting cathode materials for lithium-ion batteries is ensuring that they show excellent electrochemical stability and performance. Cathode materials must also be capable of sustaining prolonged charge and discharge cycles to achieve maximum efficiency. Cathodes and anodes both accumulate and release lithium ions to facilitate charge and discharge, but the choice of material is critical in ensuring stability and performance.Anode Material Effect on Lithium Ion BatteryAnode material is another important consideration in lithium-ion battery design. Carbon-based anode materials provide exceptional stability and performance, making them the preferred option for most batteries. However, non-carbon materials, such as silicon and lithium metal, are now preferred owing to their enhanced storage capacity and charge transportation abilities.Challenges in the Lithium-Ion Battery DesignDespite the advantages of using lithium-ion batteries, the technology is still facing several challenges when it comes to design, development, and implementation. The primary challenges include safety concerns, production costs, and environmental impact, mainly due to the composition of active materials. Improving battery sustainability and recyclability is one of the primary goals of future Li-ion battery research.The Future of Lithium-Ion BatteriesLithium-ion batteries have become an essential power source for numerous portable devices, electric vehicles, and stationary backup power units. However, as demands for energy storage and power mobility increase, the lithium-ion battery's future is changing rapidly. Achieving higher power density, storage capacity, and reliability are among the key future advancements expected in Li-ion battery research.ConclusionUnderstanding the mechanism of lithium-ion battery is necessary in selecting and designing the right battery for various applications. The core principles behind lithium-ion battery use an electrochemical process that depends on the rechargeable exchange of ions between the anode and cathode through the electrolyte. The cathode, anode, and electrolyte are the components that ensure efficiency, stability, and performance in Li-ion batteries, and improvements in these areas are expected to drive their future development.Quote InquiryContact us

Lithium-ion batteries have the advantages of high voltage, high capacity, high energy density and long life, so they are used in smart phone batteries, electric vehicle batteries, household batteries and so on. However, in recent years, the number of fire accidents caused by lithium-ion batteries such as smartphones has increased rapidly, and the safety (danger) of lithium-ion batteries has been recognized, and improving this safety is the subject of popularization of lithium-ion batteries. As the Internet of Things advances, the importance of lithium-ion batteries will increase, so increasing your knowledge of lithium-ion batteries will help you live a more comfortable life.In particular, it is well known that the performance of lithium-ion batteries tends to deteriorate under conditions that significantly deviate from normal use temperatures (such as high or low temperatures), and they can even operate under harsh conditions (such as high or low temperatures). The basic thing is that design can be done. The temperature at which a lithium-ion battery can be used is called the operating temperature range or simply the temperature range.(1) What is the upper limit of the operating temperature range of lithium-ion batteries?The upper limit of the operating temperature range of lithium-ion batteries is mainly determined at high temperatures where the capacity does not deteriorate, the internal resistance does not increase, and the battery does not explode and other dangerous temperatures. As described on this page about the high temperature characteristics of lithium-ion batteries, under normal circumstances, the chemical reaction of the negative electrode of lithium-ion batteries (SEI film growth) is the main cause of capacity degradation, internal resistance increase, etc.Since this deterioration is a chemical reaction, it follows a formula called Arrhenius's equation, which is characterized by a faster rate of deterioration at high temperatures. In other words, once deterioration occurs in a high temperature environment, it will appear in a form of deterioration that cannot be refreshed (resurrected). Therefore, in order to extend the life of lithium-ion batteries, be sure not to expose them to high temperatures.In addition, when the temperature exceeds the operating temperature range, the diaphragm, which is an integral part of the lithium-ion battery, begins to shrink, resulting in a short circuit caused by direct contact between the positive and negative electrodes. When a short circuit occurs, an exothermic reaction occurs, leading to further contraction of the diaphragm and the risk of further short circuits. This causes the temperature to rise rapidly, causing various exothermic reactions such as the reaction between the electrolyte and the negative electrode, the decomposition reaction of the electrolyte, and eventually leading to the risk of thermal runaway leading to rupture and fire. Although it depends on the positive electrode material, negative electrode material, electrolyte, etc., which constitutes the lithium-ion battery, the upper limit of the operating temperature range is often around 60 ° C due to the above reaction.(2) What is the lower limit of the operating temperature range of lithium-ion batteries?On the other hand, the lower limit of the operating temperature range of the lithium-ion battery is set to ensure that the output will not drop too much at low temperatures and prevent electrical deposition during rapid charging at low temperatures. As explained by the relationship between external temperature, capacity, and internal resistance, the internal resistance of all batteries, including lithium-ion batteries, increases at low temperatures. (In contrast, the ohmic resistance of a metal increases with decreasing temperature.)If the internal resistance of the battery increases, the output decreases, so if the battery is installed in the product, there is a risk that the product will not operate. In addition, when the lower limit of the operating temperature range is specified, the operating temperature range should be set to prevent this from happening, because rapid charging at low temperatures can lead to the phenomenon of negative electrodeposition, which significantly reduces the battery capacity and output has been set lower limits. Due to these factors, the lower limit of the temperature range for lithium-ion batteries is usually around -20 to 0°C, although this depends on the product.(3) How to expand the temperature range of lithium-ion batteriesSo, can we expand the temperature range (operating temperature range) of lithium-ion batteries by doing this? On the high temperature side, the main cause of degradation is the formation of sediment (SEI) due to the reaction between the negative electrode material and the electrolyte on the negative surface.In particular, by adding additives such as VC (vinylidene carbonate) and FEC to the electrolyte composition, and optimizing the ratio of other substances such as ethyl carbonate (EC) and diethyl carbonate (DEC), the performance of lithium-ion batteries can be improved. In some cases, degradation at high temperatures is greatly reduced. Therefore, electrolyte optimization is very important for extending the temperature range at high temperatures. (Of course, if the type, composition or electrode structure of the positive and negative materials is not suitable, there are also cases where the material deteriorates first, but in most cases, the main cause is the electrolyte.)In addition, it is best to use lithium titanate, because lithium titanate is a material that is not easy to cause electrodeposition at low temperatures, otherwise even the use of graphite negative electrode will reduce the available capacity of the negative electrode. One way to lower the lower end of your operating temperature range is to mix a small amount of a substance with a very low melting point (below freezing), such as PC (Propylene carbonate).However, if the PC component is too high, the SEI will not form well with the graphite negative and the battery performance will deteriorate significantly, so carefully consider the material composition before using this method. Ultimately, materials such as electrolytes, anode materials, and negative materials and their combinations need to be optimized, and various evaluations and considerations are made.(4) What are the temperature characteristics of lithium-ion batteries?Previously explained the temperature range of lithium-ion batteries, there is a similar term to the temperature range called temperature characteristics. The temperature characteristic of a lithium-ion battery is a vague term, similar to the term temperature range, which basically refers to "a wide operating temperature range" or "the temperature (high or low) when used in the end product." It is used as an indicator to show whether the required values for yield, capacity, etc., are being met. It can also be used as a general term to describe high temperature characteristics and low temperature characteristics. In addition to the operating temperature range, it is also necessary to understand the term temperature characteristics.

Ceramic materials are a broad category that includes a variety of inorganic nonmetallic materials obtained through high-temperature processing (such as sintering), usually in powder or granular form. A representative electrolyte in solid electrolyte is ceramic-based solid electrolyte, ceramic-based solid electrolyte has some beneficial inherent characteristics, such as non-flammability, large mechanical strength, wide electrochemical stability window, etc., they have unparalleled advantages in safety and service life, is one of the important directions of solid electrolyte research at home and abroad. Ceramic based solid electrolyte mainly includes oxide series and sulfide series, of which the oxide series mainly includes perovskite type, garnet type, LISICON (lithium superionic conductor) type, NASICON (sodium superionic conductor) type, sulfide series is mainly thiophosphate system. The representative material of perovskite solid electrolyte is LLTO (lithium lanthanum titanum oxide/lithium lanthanum titanate, Li0.33La0.56TiO3), and the representative material of garnet solid electrolyte is LLZO (lithium zirconium oxide/lithium lanthanum zirconate, Li7La3Zr2O12). The representative material of NASICON solid electrolyte is LATP (lithium aluminum titanium phosphate, Li1.3Al0.3Ti1.7(PO4)3), these three are the material types of the production line layout at present, and there are few reports about LISICON solid electrolyte. Although the solid electrolyte of sulfide in the phosphate thioate system has a high lithium ion conductivity, its stability is relatively poor, it may also release hydrogen sulfide gas when in use, and its mechanical properties are also relatively poor, so it may be mainly used in lithium-sulfur batteries. The introduction and application of Perovskite type LLTO solid electrolyteThe molecular formula of typical perovskite ceramics is ABO3, the A site is generally rare earth or alkaline earth element ion, the B site is A transition metal ion, and the A and B sites can be partially replaced by metal ions with similar radii to keep their crystal structure basically unchanged. Perovskite structure composite oxides are usually structurally stable, where Li+ is transported by vacancy transition mechanism, that is, Li+ directional transition to adjacent vacancy to generate lithium ion conductance.Currently, perovskite-structured LLtos (lithium lanthanum titanum oxide/lithium lanthanum titanate, Li0.33La0.56TiO3) have high crystal conductivity in crystalline solid electrolytes. In 1993, Inaguma et al. found that the room temperature ionic conductivity of LLTO single crystal body could reach 10-3S·cm-1, but its polycrystalline conductivity was two orders of magnitude smaller than that of monomer. The short-plate effect made the total conductivity of LLTO ceramics low, thus failing to meet the requirements of practical application in lithium batteries. The total conductivity should be improved by doping modification. In view of the problems existing in LLTO, the study of regulating crystal structure and improving electrochemical performance through doping modification of LLTO has been widely reported. At present, LLTO doping is divided into A-site doping, B-site doping and AB site co-doping. The use of rare earth elements in the sintering process can improve the LLTO-induced density and reduce the porosity, thus reducing the grain boundary impedance. The three-dimensional skeleton constructed by rare earth ions with large radius is conducive to ion diffusion and migration, and its doping can increase the LLTO cell volume, thereby expanding the ion transport channel and stabilizing the highly conductive cubic phase of LLTO. The introduction and application of Garnet type LLZO solid electrolyteThe general formula of garnet structure is A3B2(XO4)3, in which ABX coordinates with eight, six and four oxygen ions respectively to form dodecahedron, octahedron and tetrahedron, which together build a three-dimensional skeleton structure. At present, the most studied garnet solid electrolyte is LLZO (Lithium zirconium oxygen/lithium lanthanum zirconate, Li7La3Zr2O12), and its main raw materials are LiCO3, La(OH)3, ZrO2 and Al2O3.LLZO has two crystal structures: cubic phase (c-LLZO) and tetragonal phase (t-LLZO), and the most significant difference between the two structures is the occupation of Li, in the cubic phase Li partially occupies the gap position, while in the tetragonal phase Li occupies the gap position. Among them, c-LLZO has higher conductivity than t-LLZO, and its crystal skeleton network is composed of La3+, Zr2+ and O2- ions, and Li ions are distributed in the crystal grid. The shortest distance between Li ions in adjacent positions is the main reason for fast ion transport, and thus provides high ionic conductivity. At 25℃, the ionic conductivity of LLZO is 3×10-4S/cm, and the proportion of its grain boundary resistance to the total resistance is less than 50%. Therefore, the overall ionic conductivity of LLZO is in the same order of magnitude as the intracrystalline ionic conductivity, ensuring its high overall ionic conductivity as a solid electrolyte. LLZO solid electrolyte has great application potential in all-solid-state batteries, LLZO does not react with lithium metal, has low interface and grain impedance, and is relatively stable in air, and the strength and hardness of the densified ceramics sintered by LLZO heat treatment are relatively high. However, usually undoped LLZO has the advantages of stable electrochemical performance and wide electrochemical window, but the phase structure stability is poor, the vibration density is low, has a large grain boundary resistance and low room temperature ion conductivity, and will have a large interface resistance in the application of all-solid-state batteries. In addition, LLZO is exposed to air with moisture and CO2, and Li2CO3 will be generated on the surface due to the role of H+/Li+ exchange, resulting in gradual deterioration of performance. In order to enhance the chemical stability of LLZO system solid electrolyte in atmospheric environment, LLZO is mainly modified by doping different metal elements, the purpose is to stabilize the cubic phase structure, optimize the preparation route, reduce its interface resistance and grain boundary resistance, and improve its room temperature ionic conductivity.LLZO, as one of the most marketable solid electrolyte materials, has attracted the attention of many researchers, and through in-depth understanding of the crystal structure of LLZO and optimization of the structure of lithium-rich garnet by element doping, the lithium ion conductivity of LLZO has been improved by an order of magnitude. Although researchers have made a large number of attempts to build LLZ-based solid-state batteries and develop a series of effective strategies to solve the problem of positive /LLZO and negative /LLZO physical contact, up to now, there is indeed no mass-produced product that can significantly outperform traditional lithium-ion batteries in all aspects. The introduction and application of NASICON LATP solid electrolyteThe general formula of NASICON type material is M1xM2(2-x)(PO4)3, M1 and M2 can be a variety of different metal elements, A13+ doped NASICON type solid electrolyte LATP (lithium aluminum titanium phosphate, lithium titanium), Li1.3Al0.3Ti1.7(PO4)3) is one of the hot research objects of solid electrolyte in recent years.LATP has a complex crystal structure consisting of alternating layers of Li/Ti tetrahedrons and Al/PO4 octahedrons. The Li/Ti tetrahedrons form a three-dimensional frame by connecting shared vertices, while the Al/PO4 octahedrons fill the space between the tetrahedrons. This structure creates channels through which lithium ions can move. LATP can be synthesized by a variety of methods, including solid-state reactions, sol-gel methods, and hydrothermal methods. In one common method, lithium carbonate, alumina (Al2O3), titanium oxide (TiO2), and ammonium dihydrogen phosphate are mixed in stoichiometric proportions and heated in a reducing atmosphere at high temperatures (usually 900 to 1200 ° C) to form LATP ceramics. Some of the advantages of LATP include relatively high ionic conductivity, a wide electrochemical stability window, good mechanical stability, compatibility with lithium metal anodes, low reactivity with cathode materials, and a wide temperature range. In addition, LATP is not easy to form dendrites, which can improve the safety and cycle life of the battery. However, LATP is relatively expensive and has lower ionic conductivity than LLZO.

Analyzing the Performance and Design of the Tesla Model 3 Battery: A Study by Sandro Stock et al.Sandro Stock et al. from the School of Engineering and Design at the Technical University of Munich, Germany, disassembled and evaluated the electrochemical performance, battery design and chemical material system of the square hard-shell lithium iron phosphate battery used in the Tesla Model 3 to obtain the process-structure-performance relationship of the battery. The test analysis methods include weighing, geometric measurement, cross section analysis, material characterization by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), electrolyte characterization, and electrochemical performance analysis of half and full cells.The Tesla Model 3 Battery: Capacity and Discharge TestingThe battery is obtained from the battery pack of the Tesla Model 3 produced in December 2020. The battery pack has a total energy of 55 kWh and consists of two 25 series 1 and two 28 series 1 battery modules, configured as a battery pack in 106 series 1. After removing the battery from the battery pack, charge and discharge the battery several times at C/20 to determine the battery capacity of 161.5Ah. After that, the battery is fully discharged using a constant current (CC) of 1A, followed by a constant voltage (CV) discharge at 2.65V, before the battery is transferred to a custom glove box for dismantling.Evolution of Tesla Model 3 Batteries: From 18650 Cylinder to Square LFPThe Model 3 initially featured the same 18650 cylinder NCA battery pack as the Model S/Model X. Later, Tesla introduced new battery iterations, including the 21,700 cylinder NCA batteries produced by Panasonic and others, which are used in the vast majority of performance and long-range Model 3s. There are also 21,700 cylindrical nickel-cobalt-manganese (NCM) batteries, which are used in Tesla cars produced in China and Berlin. In addition, Tesla has also begun using CATL's square lithium iron phosphate (LFP) battery in the standard version of the Model 3.Analyzing Battery Components through Disassembly and Microscopic ExaminationDuring the disassembly process, images were taken using the built-in microscope, and an example of the picture obtained was shown in Figure 2. After the battery is broken down into the shell, coil and top cover, the geometric dimensions of each component are recorded for graphic reconstruction using CAD. During the dismantling process, electrolyte residue was found at the bottom of the housing, which was removed and packaged for further analysis. The coils were then carefully dismantled and samples were taken every 50 cm. The electrode samples were washed with diethyl carbonate (DEC) to remove excess electrolytes or by-products, and dried before further examination of electrode parameters such as length, thickness, overlap and weight. When assembling a button cell, the electrode first removes the coating on one side of the electrode with acetone to obtain a single-coated pole piece.In summary, this paper disassembled and analyzed the 161.5Ah square flat coil hard shell LFP battery in the Tesla Model 3, decomposed the battery to the material level, and tracked the process steps and manufacturing characteristics. The specific energy of the battery was 163 Wh/kg and the volumetric energy density was 366 Wh/L. The cell presents a low void volume of 6.4% and a fluid collector thickness of 5µm for copper and 12µm for aluminum. The jelly roll core is connected to the top cover in a butterfly design to facilitate the welding process. Cross-sectional and microscopic analysis of the battery cover revealed the application of a variety of laser welding processes, providing high mechanical stability and air tightness. The coating of the electrodes showed a high degree of uniformity, with thickness fluctuations of less than 2μm. Scanning electron microscopy (SEM) images reveal bimodal particle distributions within the pure graphite anode and LFP cathode, where the positive electrode edges are covered with Al2O3 ceramic layers. Electrochemical analysis showed that the performance of the inherent electrolyte was better than that of the ordinary LP572 electrolyte.

Background Recently, there have been a lot of fire accidents caused by lithium-ion batteries, and I think the interest in lithium-ion batteries is increasing. However, there are certain aspects of lithium-ion batteries that are not well known, such as their composition, various safety features, and related terminology, which I have also described.1.What is the capacity retention rate?When secondary batteries such as lithium-ion batteries undergo cycle tests, floating charge tests, preservation tests and other battery evaluation tests, the battery will deteriorate, and its capacity will gradually decrease from the initial capacity [mAh or Ah]. The capacity retention rate is the ratio of the capacity at a point [mAh,Ah] to the initial capacity [mAh,Ah]×100, expressed as a percentage. 2.cycle test capacity retention rateAn example of the capacity retention rate of a lithium-ion battery during cycle testing is shown below. In simple terms, the cycle test is to evaluate the deterioration of the battery during repeated charging and discharging, and one of the evaluation items of the cycle test is the capacity retention rate. A battery that can maintain a high capacity retention rate even after multiple cycles is a good battery. The capacity retention rate of the battery depends not only on the number of cycles, but also on the charge and discharge rate during the cycle, the ambient temperature, etc.The reduction in the number of known cycle tests and the capacity maintenance rate can be obtained by the degradation coefficient Kc in the cycle test and the degradation coefficient Kf in the float test. Reduction of capacity maintenance rate = degradation coefficient Kc× number of root cycle tests + degradation coefficient Kf× route passage time. Here, the degradation coefficient Kc in the cycle test is strongly related to the DOD(depth of discharge) of the battery.In other words, the greater the DOD in the cyclic test, the greater the expansion and contraction of the active material due to charge and discharge, which tends to increase the contact resistance between the active materials and between the electrode foil and the active material. In addition, it should be noted that when conducting a cycle test, if the amount of electrolyte in the battery is too small, there will be a phenomenon called drying (liquid depletion), which is not good for the battery.

Enhancing Lithium-Ion Battery Technology: Strategies for Improving Energy Density and PerformanceWith the increasing demand for lithium-ion batteries, high energy density and high power density lithium-ion battery technology has become one of the research hotspots. Increasing electrode thickness, material modification and development of new materials can effectively improve the energy density of the battery, while the electrode microstructure parameters such as porosity, pore size and distribution, and curvature of the electrode are the key factors determining the performance of the electrode and the battery.Analyzing Pore Characteristics of Lithium-Ion Porous Electrodes: Methods and SignificanceFrom the current research of lithium-ion porous electrodes, it can be found that the actual porous electrode pores are affected by the accumulation effect and filling effect of particles, and the pore size and distribution are not uniform, and the zigzag degree is difficult to characterize. In order to characterize the pore characteristics of porous electrodes, researchers have devoted themselves to the development of efficient and fast methods for measuring the zigzag degree, such as the gas transmission resistance measurement method , the heat exchange method for hydrodynamic simulation of porous electrodes, the FIB-SEM reconstruction of 3D electrode structure measurement method, and the symmetric battery electrochemical impedance spectroscopy (EIS) test method. Among them, electrochemical impedance spectroscopy is easy to operate, and the test time is short. Because the electron transmission resistance of lithium-ion porous electrodes is usually small, the true curvature of porous electrodes can be obtained by electrochemical impedance spectroscopy. In addition, the measurement method of symmetrical battery electrochemical impedance spectroscopy can also be used to analyze the electrolyte wettability and the membrane curvature of the electrode plate, and has a certain guiding significance for the judgment of the production line electrolyte wettability time.Electrochemical impedance spectroscopy (EIS) was used to measure symmetrical cells assembled with negative electrode plates of different compaction. The ion resistance of each pole piece was obtained by fitting the EIS spectrum, and then the ion resistance value was substituted into the formula to obtain the McMullin number of the pole piece, as shown in Figure 5. It can be seen from the trend of the data that the ion resistance and McMullin number increase with the increase of the compaction density of the electrode sheet, indicating that the curvature of the graphite negative electrode sheet increases with the increase of the compaction.Effect of Compaction Density on Electrolyte Performance and Ion Transmission in Lithium-ion BatteriesWith the increase of compaction density, the contact between graphite particles and conductive particles is more dense, the performance of the absorbing electrolyte deteriorates, and the electrolyte is difficult to infiltrate, making the migration of lithium ions more difficult, increasing the ion transmission impedance, resulting in an increase in the curvature of the pole sheet.The Impact of Electrode Compaction Density on Battery PerformanceGenerally speaking, within the compaction range allowed by the material, the greater the electrode compaction density and the more active material contained per unit volume, the higher the capacity of the battery can be done. However, when the compaction of the pole plate is too high, the porosity is reduced, the greater the zigzag degree, the longer the lithium ion transmission path, which will seriously reduce the magnification performance and cycle performance of the battery. Especially for thick electrodes, low curvature is one of the key factors in the design of electrode structure. Therefore, compaction density is very important for battery design. We can preliminatively characterize the magnification performance of the pole sheet in the battery by testing the curvature of the pole sheet, so as to determine the appropriate design scheme of the pole sheet.

Basquevolt makes breakthrough in solid-state battery technology with successful production of 20Ah battery and plans for 80Ah batteries by end of year    Recently, Spanish solid state battery developer Basquevolt announced that the company's "A sample line" in Spain has successfully produced the first 20Ah battery, and is expected to be able to manufacture 80Ah batteries by the end of this year. Revolutionizing the Battery Industry: A Look at the State-of-the-Art Plant Producing High-Energy Lithium-Ion Batteries for Electric Vehicles    It is reported that the construction of the plant began in the summer of 2023, covering an area of 4,500 square meters, the plant has a process process that meets current lithium-ion battery industry standards, including the manufacture of patented electrolytes. The plant is now operational and equipped with state-of-the-art machinery for manufacturing batteries, enabling it to produce the first 20Ah batteries, with the first samples to be delivered to potential customers in the coming months. The company plans to expand the production process to 80Ah batteries in a few months, which means getting cells with enough energy density to make battery packs for electric vehicles.The Future of Electric Vehicles: Solid-State Batteries Leading the Way    Compared to traditional lithium-ion batteries (liquid), the technology developed by Basquevolt is already considered the "battery technology of the future" because solid-state batteries will allow the emergence of a "new generation of batteries" : with higher energy density (up to 50%), safer (non-flammable) and lower cost (approximately 30% less). "Our company's goal is to drive the true adoption of electric vehicles with 'Made in Europe' technology. The cost of electric vehicles is much higher than that of traditional internal combustion engine vehicles, and it is not enough to establish a regulatory framework to ban fuel vehicles, it must be made available to the billions of people who cannot currently afford electric vehicles, "said Francisco Carranza, CEO of Basquevolt.   Basquevolt: Leading the Charge in Solid-State Battery Technology in Europe    Basquevolt is a company focused on the development of solid-state battery technology, aiming to become the European leader in the next generation of solid-state lithium battery technology, based on the CIC energiGUNE patented composite electrolyte. In addition to producing 20Ah batteries, Basquevolt also plans to produce solid-state batteries at its 1GWh plant in Victoria-Gasteitz by the end of 2025, with the goal of reaching 10GWh production by 2027. The goal is supported by the founding shareholders of the Basque government, Iberdrola, CIE Automotive, Enagas, EIT InnoEnergy and CIC energiGUNE. 

AbstractThere are many factors that affect the safety of lithium-ion power batteries. Among them, the battery safety problems caused by the cracking of the positive electrode plate are easy to produce burrs, abnormal protrections and fractures in the subsequent electrode assembly process, which have attracted much attention in recent years. In this paper, through the experiment of mixing design, the ratio of auxiliary materials in the anode material is optimized to reduce the roll elongation of the electrode sheet. At the same time, adjusting the thickness of the ceramic layer can effectively control the difference of the elongation of the active material coating area and the ceramic layer electrode sheet in the rolling process, reduce the arc rate of the electrode sheet after paving, and explore an effective method to solve the crack of the pole ear during the preparation of the positive electrode sheet of the power battery.1.1 Experimental process1.1.1 Specific experimental methodsThe solid content of ternary NCM811 is set at 95%, and the total solid content of PVDF, SP and KS6 is 5%. The content of solvent NMP in the slurry is fixed at 30%. The verification ratios of PVDF, SP and KS6 were 1%-2%, 1%-2% and 1.2% -2.4%, respectively. PVDF, SP, KS6 ratio optimization method using Minitab software, mix optimization design (DOE), simplex design diagram, extreme vertex design and center point strengthening scheme, 7 groups of experiments. 1.1.2 Slurry preparation of electrode sheetThe specific process is as follows: First, PVDF is dissolved in NMP solvent, PVDF solution with 7% solid content is formed in the agitator, and transferred to the stainless steel bucket for storage; Subsequently, SP, KS6 and NMP were pre-stirred in a blender for 30min; Then add the prepared PVDF solution and stir for 30min; Finally, the NCM811 is divided into two times according to weight and added to the stainless steel drum, each stirring time is 20min; In the above stirring process, the parameters of the agitator are set as the revolution speed of 25 revolutions /min and the rotation speed of 800 revolutions /min, and the total mixing time is 240min.2.1 Conclusion:In this paper, the elongation of the polar plate can be reduced by optimizing the content ratio of PVDF, SP and KS6 under the condition of obtaining the same compaction density. At the same time, the elongation after rolling can be controlled by controlling the thickness of the ceramic layer before rolling and the thickness after cold pressing (the best ratio is 120%±9%). Both effects can effectively reduce the arc rate of the positive electrode sheet after paving, and can solve the problem of the root of the pole ear cracking during the preparation of the positive electrode sheet of the power battery.