FURNACE ATMOSPHERIC CONTROL FOR LITIUM-ION BATTERY CATHODE MATERIAL MANUFACTURE

Abstract

The present invention relates to a method and apparatus for controlling the atmosphere of a multi-zone calcination furnace for the production of high-quality nickel-rich cathode materials for lithium-ion and solid-state batteries. A high-quality oxygen-rich atmosphere is maintained to ensure the quality of the cathode materials. The atmosphere control system continuously measures and analyzes the composition of the calcination furnace atmosphere in different zones and regulates the flow rate of the oxygen-rich atmosphere into the furnace to optimize the calcination process.

Description

ATMOSPHERIC CONTROL OF FURNACES FOR THE MANUFACTURE OF CATHODEORES LITHIUM-ION BATTERY Invention Engineering Field The present invention relates to the control of an atmospheric furnace. for the manufacture of lithium-ion battery cathode materials. Background of the Invention The increasing demand for technology to reduce greenhouse gas emissions, such as carbon dioxide, have created the need for the development of alternative means of collection and clean energy storage. Reducing carbon dioxide emissions significant improvements can be achieved, for example, through electrification mobility. Rechargeable lithium-ion batteries (LIBs) have widely used in consumer electronics devices and with quickly enter the electric vehicle (EV) and storage market large-scale stationary energy. State-of-the-art LIB systems typically consists of a graphite anode, separator, aqueous electrolyte, and cathode containing lithium. The cathode material determines the density energy and battery voltage, so that there is exploration cathode material intensification to further increase the density energy from the entire battery system. Conventional cathodes, such as LiCcoO2, LiMn2O4, LiFePO4, and LiNixMnyCozO2 (NMC) have been used commercially as cathode materials for LIBs. Among these chemicals, Ni-rich LiNixMnyCozO2, where x 2 0.5, or NMC which Rich in Ni, it has been considered as a cathode material promising, especially in the EV market. Ni-rich NMC shows the high discharge capacity that can be achieved (200-220 mAh g-1l), which indicates an increase in energy density over further (-800 wh kg-1l) compared to cathodes conventional. See, for example, W. Liu, and friends, Angew. Chem. Int. Ed. 54 (2015) 4440-4457: . Manthiram, and friends, Adv. EnergyMater. 6 (2016): Y.-K. Sun, and friends, Nat. Mater. 11 (2012) 942-947 and Y.-K. Sun, and friends, Nat. Mater. 8 (2009) 320-324. Increased nickel content (50.5 mole fraction) in the material cathode requires the use of oxygen as the furnace atmosphere calcination which allows complete oxidation of the metal generating chemicals such as Lithium Nickel Manganese Cobalt (NMC) and Lithium Nickel Cobalt Aluminum (NCA), Lithium Nickel Manganese Cobalt Aluminum (NMCA), Nickel Cobalt Boron (NCB). Although these cathode materials exhibit low density very interesting energy, its electrochemical performance is very sensitive to synthesis methods and treatment conditions post-calcination. A widely used synthesis method for the manufacture of these cathode materials includes the manufacture of precursor, mixing of Lithium source and calcination step in high temperatures ranging from 1700-1050 degrees Celsius. See, for example, MH Lee, and friends, Electrochim. Acta 50 (2004)939-948 and van Bommel, and colleagues, Chem. Mater. 21 (2009) 1500-1503. Understanding and controlling oxygen-rich furnace atmospheres during the calcination step it is very important to provide the necessary materials high quality Ni-rich cathode material. Atmospheric control careful during the calcination process can produce cathode material which is rich in Ni with good operational performance and service life. better, and also reduce the cost of the cathode manufacturing process. Existing atmospheric control systems for treatment processes heat in other industries is used with an inert atmosphere and some reactive atmospheres, for example, argon, nitrogen, hydrogen, ammonia, natural gas or mixtures thereof. The treatment process This heat is usually intended to prevent oxidation and decarburization by reducing the oxygen or water content in atmosphere. In contrast, the manufacture of cathode materials rich in Ni with high quality requires calcination of precursors at relatively high temperatures in a strongly oxidizing atmosphere. Therefore, there is a need for equipment and effective, reliable, and cost-effective method for monitoring and control of the oxygen-rich atmosphere required in industrial scale calcination furnaces for the manufacture of materials Ni-rich cathode. Brief Description of the Invention The present invention describes a method and apparatus comprising of the atmospheric control system. The atmospheric control system is designed to control the oxygen-rich atmosphere in the furnace calcination for the preparation of Ni-rich cathode materials with high quality for lithium ion and solid-state batteries (solid-state batteries are a battery technology that uses other solid electrodes and solid electrolytes. The calcination process preferably takes place in a furnace with several zones temperature. Preferably there are at least three zones, the preheating where the cathode precursor material enters the furnace and heated from ambient temperature to processing temperature desired. During the preheating process, impurities (humidity, carbon dioxide and harmful impurities others) are released in the form of gas. The material is then moves from the preheating zone to the furnace hot zone. Material The calcined product is then moved from hot zone to zone cooling before leaving the furnace. The atmospheric control equipment preferably consists of three main components, (1) a network of sensors installed in several furnace temperature zone: (2) oxygen delivery system that consists of a mass flow controller which, when connected to a oxygen source, capable of providing some oxygen flow to in several temperature zones: and (3) process control systems which is able to connect and control sensors and systems oxygen delivery. The equipment can be combined with in the furnace design or installed as a furnace retrofit that already exists. The method consists of atmospheric control equipment to monitor and regulate the atmosphere in several temperature zones furnace so that the hottest zone of the furnace, where the cathode material finally formed, had an oxygen-rich atmosphere relatively clean with very low levels of impurities (humidity, carbon dioxide and harmful impurities others) compared to the preheating zone. Gas flow oxygen-rich processes to various zones tailored to creating movement of the furnace atmosphere away from the hot zone and towards the inlet and outlet of the furnace. This maintains oxygen-rich atmosphere with high purity in the zone heat and minimize unwanted side reactions between materials and hazardous impurities (moisture and carbon dioxide) in the hot zone. This brief description is provided to introduce selection of concepts in a simple form that is explained more Continued below with a detailed description. This brief description not intended to identify the main technical features or the essential technical characteristics of the claimed subject matter, nor intended to be used to limit the scope of the subject matter claimed discussion. Aspect 1: A furnace atmosphere control method for furnaces calcination for the manufacture of lithium ion battery cathode materials, The method consists of the following steps: (a) measure the first oxygen concentration, the concentration first humidity and first carbon dioxide concentration of atmosphere inside the first zone of the calcination furnace: (b) measure the second oxygen concentration, concentration second humidity and second carbon dioxide concentration of the atmosphere in the second zone of the calcination furnace, where the second zone bordering the first zone and the boundary between the first zone and secondly, it is located where the atmospheric temperature reaches a certain temperature predetermined immersion: (c) supplying oxygen process gas consisting of at least 50 percent oxygen by volume, in independent, to the first and second zones of the calcination furnace:j (d) controlling the flow rate of the first stream of process gas oxygen into the first zone as a function of the least amount one selected from group (i) oxygen concentration first measured in step (), (ii) moisture concentration first measured in step(), and (iii) carbon concentration the first dioxide measured in step (): (e) controlling the flow rate of both process gases oxygen into the second zone as a function of the least amount of one of the one selected from group (i) second oxygen concentration measured in step (b), (i1) the second moisture concentration measured in step (b), and (iii) carbon concentration second dioxide measured in step (b),: and (£) maintain the flow rate of the first stream of process gas oxygen at or below the flow rate of both process gases oxygen, to prevent the flow of gas from the first zone into the second zone. Aspect 2: Method of Aspect 1, where step (d) is more further consists of increasing the flow rate of the first gas stream oxygen process if at least one of the selected group (i) the first oxygen concentration measured at step () is less than the specified set point (Set point is an element used to express a value desired or reference value of a dynamic variable or variable controlled from a system), (11) concentration the first humidity measured in step (a) is greater than predetermined set point, and (iii) carbon concentration the first dioxide measured in step (a) is greater than predetermined set point. Aspect 3: Method of Aspect 1-2, where step (e) further consists of increasing the flow rate of the second stream oxygen process gas if at least one of the selected group (1) the second oxygen concentration measured in step (b) less than the specified set point, (11) the second moisture concentration measured in step (b) is greater greater than the specified set point, and (111) the second carbon dioxide concentration measured in step (b) greater than the specified set point. Aspect 4: Methods from Aspects 1-3, hereinafter consist of: (h) repeat steps (a) to (£) all at once simultaneously heating, gradually, the first zone up to first temperature and maintain the second zone at the temperature second, where the second temperature is greater than or equal to first temperature. Aspect 5: Methods from Aspects 1-4, further consisting of from: (1) repeat steps (a) to (£) simultaneously simultaneously feeding a number of battery cathode precursor materials lithium ions into the first zone for a sufficient period of time to heat the material to the temperature of the material has been determined, then feed the material into second zone. Aspect 6: Methods from Aspects 1-5, further consisting of from: (J7) measures the third oxygen concentration, concentration third humidity and third carbon dioxide concentration of the atmosphere within the third temperature zone of the furnace, where the zone the third temperature zone borders the second temperature zone: (k) controlling the flow rate of the three process gases oxygen into the third zone as a function of the least one selected from group (i) oxygen concentration the third measured in step (J7), (ii) moisture concentration the third measured at step (jJ), and (iii) concentration third carbon dioxide measured in step (jJ): and (Ll) maintains the flow rate of the three process gases oxygen at or below the flow rate of both process gases oxygen, to prevent the flow of gas from the third zone into the second zone. Aspect 1: The method of Aspects 1-6, wherein the precursor material lithium ion cathodes are selected from a group consisting of precursor for: lithium nickel manganese cobalt (NMC): lithium nickel cobalt aluminum (NCA): Lithium Nickel Manganese Cobalt Aluminum (NMCA): Nickel Cobalt Boron (NCB) and their combinations. Aspect 8: The method of Aspects 1-7, wherein the precursor material The cathode includes a nickel mole ratio greater than 0.5. Aspect 9: The method of Aspects 1-8, wherein the process gas oxygen includes a purity of at least 90 percent based on volume. Aspect 10: Methods from Aspects 1-9, further consisting of from: (m) remove a sample of the furnace atmosphere from the first zone through the sample path, and (n) sending samples to at least one analyzer externally configured to measure the parameters that selected from the group consisting of: oxygen concentration: carbon dioxide concentration, dew point, ammonia, SOx and NOx. Aspect 11: A furnace atmosphere control method for calcination furnace for manufacturing lithium battery cathode materials ion, the method consists of the following steps: (a) measure the first concentration of atmospheric oxygen in the atmosphere first zone of calcination furnace:j (b) measure the second oxygen concentration in the second zone calcination furnace, where the second zone borders the second zone first and the boundary between the first and second zones is located where atmospheric temperature reaches the immersion temperature that has been determined: (c) supplying oxygen process gas consisting of at least 50 percent oxygen by volume, in independent, to the first and second zones of the calcination furnace:j (d) controlling the flow rate of the first stream of process gas oxygen into the first zone as a function of oxygen concentration first measured in step (la): (e) controlling the flow rate of both process gases oxygen into the second zone as a function of oxygen concentration both measured in step (b): and (£) maintain the flow rate of both process gases oxygen at or below the first flow rate of the process gas stream oxygen, to prevent the flow of gas from the second zone into the second zone. First. Aspect 12: A device for controlling the atmosphere inside a solid state calcination furnace for the manufacture of cathode material of solid state or lithium ion batteries consisting of from: the first group of sensors, which are installed in the temperature zone first furnace, the first sensor group consisting of sensors first oxygen, first humidity sensor and carbon sensor first dioxide: the second group of sensors, which are installed in the temperature zone second furnace, the second sensor group consisting of sensors second oxygen, second humidity sensor and carbon sensor second dioxide: a custom-configured oxygen delivery system operationally placed fluidly connected to the source oxygen to deliver independently the oxygen flow that set to the first and second furnace temperature zones, process controllers are operationally configured to related to sensors and oxygen delivery systems to control the rate of oxygen delivery to the temperature zone first and second in response to signals from first and second sensor groups. Aspect 13: Equipment from Aspect 12, further consisting of from the first sampling path configured in a operational to extract atmospheric samples from within the zone the first temperature of the furnace and sends it to an external sensor first: the first external sensor operationally configured to communicate with the process controller. Aspect 14: Equipment from Aspects 12-13, wherein the sensors The first oxygen is an in-situ sensor. Aspect 15: Equipment from Aspects 12-14, wherein the sensors The first external sensor is a sensor to measure the parameters that selected from the group consisting of: oxygen, pressure, boiling point dew, carbon dioxide, ammonia, SOx, NOx and pressure differential. Aspect 16: Equipment from Aspects 12-15, where the path the first sampling includes a removal device operationally configured humidity for remove moisture from the furnace atmosphere sample. Aspect 17: Equipment from Aspects 12-16, where the zone The first furnace includes the upper area and the lower area. bottom: the first oxygen sensor is placed in the upper area and an inlet configured to deliver oxygen of the oxygen delivery system is placed in the area of ​​the lower. Aspect 18: Equipment from Aspects 12-17, where the path the first sample is passed through the furnace wall, The sampling path consists of the interior length of the made of ceramic material and placed inside furnace walls, and the exterior length is formed from steel rust-resistant and placed on the outside of the furnace wall. Aspect 19: Equipment from Aspects 12-18 where the group first sensor and first external sensor operationally configured to communicate with the first sensor node: the first sensor node is operationally configured to related to process control. Aspect 20: Equipment from Aspects 12-19 where the group The first sensor then consists of a flow velocity sensor the first gas and the second sensor group then consists of second gas flow sensor. Short Description of Image Figure 1 is a schematic of an industrial scale calcination furnace. equipped with an atmosphere control system according to the embodiment invention. Figure 2 is a flowchart showing the logic control for an example furnace zone in an embodiment of the invention. Complete Description of the Invention The following detailed description provides only exemplary embodiments. preferred, and is not intended to limit space scope, applicability, or configuration of the invention claimed. Instead, a further detailed description of the embodiment preferred examples will provide those who are experts at field with a description that allows for application preferred exemplary embodiment of the claimed invention. Various changes can be made in the function and composition elements without deviating from the spirit and scope of the invention claimed. The reference number contained in the related specification with the image can be repeated in one subsequent image or more without additional description in the specifications for provide context for other technical features. In a claim, letters are used to identify the claimed steps (e.g. (a), (b), and (c)). The letters This is used to help refer to the steps of the method. and is not intended to indicate the order in which the steps the steps claimed to be taken, except and only to the extent that the order is specifically stated in the claim. As used herein the terms “furnace” and “furnace “calcination” refers to the equipment used to heat solid precursor materials are treated to form materials Lithium ion cathode. Heat treatment process temperatures preferably ranging from 7 / 00 to 1300 degrees Celsius. As used here the term “temperature zone”, “heating zone”, and “zone” refers to the inner area furnace related to the furnace temperature profile determined. The material being heat treated moves through the zone as being treated. A zone may have a constant temperature or a temperature gradient. The boundaries between zones can be defined spatially or in terms of temperature. The boundaries between zones may be sharp or gradual. depending on the design and application of the particular furnace. As used herein the term “NMC” refers to materials that have the general chemical formula LiNixMnyCozO2. The term “NMC Ni-rich” refers to materials that have the chemical formula general LiNixMnyCozO2 where the value of x is greater than 0.5. The term “NMC 811” refers to a material that has the chemical formula LiNi9.g#MN9.1CO0.102” As used herein, the term “precursor” refers to to the raw material, in an unreacted state, which is used in the manufacture of cathode materials. Preferred cathode materials, including but not limited to, NCA and NMC, created through co-precipitation of transition metal hydroxide precursors, followed by calcination (lithiation and oxidation) with lithium compounds, preferably lithium hydroxide. In preferred embodiment, the precursor is NixMnyCo(1l-x- y) (OH)2 and the cathode material produced in calcination is NMC. As used herein the term “relationship” refers to to the ability to send and receive information, data, signals, controls, commands through any known technology. For example, the relationship between the components of a control system the atmosphere expressed can be done by one technology or more including, but limited to, fixed electrical wiring or wireless networks, such as Local Area Networks (LANs), Wireless Local Area Network (WLAN), Wide Area Network (WAN), Personal Area Network (PAN), Wireless Personal Area Network (WPAN), a telephone network such as a cellular network or a broadband network circuit switch, intranet, extranet, peer-to-peer network (A peer-to-peer network is a network in which two or more PCs share files and access to devices such as printers without requires a server computer or server software separate), Virtual private network (VPN), Internet, or other communication networks / links. Preparation of Ni-rich cathode materials, such as NMC, requires calcination in an oxygen-rich atmosphere (oxygen content in the atmosphere » 508). Preferably, the content The oxygen content of the calcination furnace atmosphere is 70 percent. (by volume) or larger, preferably 90 percent (by volume) or greater. Cathode chemicals previously (with Nickel less than 0.5 mole fraction) can calcined in air, which is known to contain 21 percent (by volume) oxygen, or in an atmosphere rich in oxygen. The disclosed invention is applicable to all the atmosphere mentioned above. Research conducted on a mixture of nitrogen- oxygen for calcination of NMC containing more than 0.5 mole fraction of nickel chemicals has shown that the content low oxygen in the gas mixture results in poor performance electrochemistry and poor cycling of the cathode material. produced. This correlation is associated with the oxidation state of nickel in the product and the size of its atomic radius. Various metals, depending on the atomic group and number its electron shells can reach different oxidation states. In the case of nickel, the most stable cation is Ni2t, which can damage the performance of the cathode material. The negative impact comes from from the size of its atomic radius which is very close to Lit, and mixing within the crystal structure. According to Le's principle Chatelier, increase in partial pressure of oxygen in the atmosphere the furnace allows more oxygen to be available for oxidize nickel to a higher oxidation state which preferred, Ni3-t. In light of these findings, current calcination processes it supplies oxygen to the furnace at a constant flow rate, with the assumption that a high constant oxygen flow rate is sufficient to oxidize the cathode material. Little or no concern is given to the important aspects of this process, which are effectively make use of the potential of the protective atmosphere and the impact on the final product becomes inefficient. In addition, process impurities, including, but limited to, carbon dioxide (CO2) and moisture (H20) can have a reverse effect on oxidation, and causes side reactions with lithium. Careful monitoring and reduction of these impurities must be controlled carefully. In addition, the composition of the furnace atmosphere, direction and speed The furnace gas flow is also important. Preferably, the calcination process carried out in a continuous furnace where the crucible contains precursors are transported through several temperature zones. temperature and its limits depend on the furnace design and the processes carried out. In general, the furnace consists of three main zones: preheating, heat (soaking) and cooling. The preheating zone is the part of the furnace where each part or material gradually increases the temperature from the initial temperature (most commonly the temperature ambient) until it reaches 'immersion temperature'. Hot zone the furnace is the part where the temperature is most stable and should be somewhat 'constant!' or maintained close to the temperature desired immersion (specifically determined for the type of processed materials). The cooling zone is where the product is cooled at the desired cooling rate (always specific materials & properties) along the zone. Preferably, the depth of the precursor material within the crucible is relatively small, to provide sufficient contact between furnace atmosphere and precursor materials. Atmosphere control system This invention optimizes the pattern and composition of atmospheric flow. furnace to ensure a more effective reaction between the materials precursors and an oxygen-rich atmosphere, in part, with measure the flow direction and velocity of the furnace atmosphere. Preferably, the process gas is injected on the side cooling of the hot zone with the aim of forcing most of the gas flow towards the furnace inlet (against the direction of movement belt) and allows some of the flow to be distributed towards cooling zone and protect the most affected parts. In the embodiment for the NMC calcination process, the inlet gas (located on the bottom side of the furnace) is placed throughout length of the furnace even though the flow distribution is uneven among the inlet. Most of the gas is introduced at the end cooling and also forced out of the furnace in the heating section the beginning of the furnace. Most of the chemical reactions between the materials and the atmosphere takes place in the initial heating zone and partly in the warming zone hot. It is important to remove any impurities that come off materials as quickly as possible and have a gas outlet at the bottom. The “dirtiest” of the furnace helps prevent these impurities enter the hot part and reverse the chemical reaction. However, it is important not to simply eliminate impurities from the furnace as quickly as possible, but also to allows sufficient partial pressure of oxygen process gas in furnace for materials that oxidize and distribute this in in the furnace in such a way that the material has sufficient exposure more uniform to the oxidizing atmosphere. In the embodiment, the direction of the atmospheric flow in the furnace determined by measuring the differential pressure between the parts different parts of the furnace and between the furnace and the outside atmosphere. In normal operation, the pressure in the furnace is preferably slightly positive to atmospheric pressure and uniform throughout the furnace (low differential). This is directly related to gas flow into the furnace. Increase in differential pressure between certain parts of the furnace indicates that the flow is not evenly distributed or so that air can enter from one the end of the furnace depends on the direction of the pressure change. In an embodiment, the atmosphere control system of the invention continuously measure and analyze oxygen, CO2, H2O, furnace pressure, furnace atmosphere flow direction and velocity flow in each zone inside the calcination furnace. Parameters- other parameters can also be measured as needed depending on on the type of material being processed. Other parameters may include, but are not limited to, impurities such as sulfur oxides (SOx) and nitrogen oxides (NOx). Process controllers related to sensors (in a directly to each sensor or to a group of sensors via nodes) are also related to the oxygen delivery system. The oxygen delivery system consists of a mass flow controller at the inlet to each furnace zone. The delivery system oxygen is fluidly connected to the oxygen source and configured to optimize oxygen flow in each zone furnace to maintain high oxygen concentration, replace CO2, H20 and other impurities, and maintain the desired direction of atmospheric flow. More preferably, the furnace has at least three zones, the heating zone initial, hot zone and cooling zone. Furnace pressure and gas velocity sensors are mounted on certain positions to monitor the furnace atmospheric flow pattern, which helps maintain high oxygen levels in the furnace by effectively removing moisture, carbon dioxide and impurities through ventilation in the walls furnace. The parameters include, but are limited to, temperature, oxygen concentration, humidity (measured as dew point) and CO2 concentration are preferred to be used to verify that the calcination furnace atmosphere is running at optimal conditions, and to determine optimal operation calcination furnace atmosphere control system by correlating atmospheric conditions with the quality of the final cathode material. Figure 1 shows a manifestation of the atmospheric control system. furnace 100) for the calcination furnace (101) used in manufacture of Ni-rich lithium ion battery cathode materials. For clarity, not all possible configurations or measurement location is indicated, but considering the options that shown, different configurations that are part of the This invention can be assembled. The furnace consists of a number of sequential heating and cooling zones maintained at different temperatures, with each zone equipped with with a series of sensors. In the embodiment of Figure 1, the furnace consists of at least one of each zone preheating (105), hot zone (107), and cooling zone (111). The cathode precursor material (115) enters the furnace in the zone preheating (105) and then transported through the hot zone (107), and then the cooling zone (111), which is visible as a product of the final cathode material (117). Preheating step, in addition to raising the temperature of raw materials, eliminating humidity, carbon dioxide and other pollutants mainly produced from the decomposition of precursors. Humidity, CO2 and impurities are preferably removed from the material before entering the hot zone where it can cause a reaction unwanted return. The oxygen source is connected to the oxygen delivery system (119). The source is preferably a rich gas mixture will be oxygen. Preferred gas mixtures include, but are not limited to limited to, a mixture of 02 and N2, purified air or combinations thereof. In one embodiment, the gas mixture contains at least 50 percent by volume of 02, more preferred by at least 70 percent by volume 02, more preferred again at least 90 percent based on O2 volume. More preferably, a gas mixture rich in oxygen has CO2 concentration less than 1 ppm, CO concentration less than 1 ppm, H2O concentration less than 5 ppm, total concentration hydrocarbons less than 1 ppm, and substantially free from metal particles, oil or grease. Preferably, a balance the impurity in the oxygen-rich gas mixture is argon and nitrogen, which is inert at process temperatures and does not have a negative impact on the processed materials. Referring to Figure 1, the oxygen delivery system (119) fluidly connected to the mass flow controller, (121), (123), (125) which feeds a gas mixture rich in oxygen into the furnace through inlet duct (127). Flow controller the mass is electrically connected to the main flow controller (131) software logic. Mass flow controller is set based on the main flow control signal to allow flow that is more or less restricted by proportional control gas flow that flows through the mass flow controller. More preferably, the inlet is located at the bottom of the furnace or in the side walls of the furnace, or both. Gases, including water vapor, CO2 and other impurities are removed from the material The precursor exits the furnace through the outlet (129) at the top of the furnace. Preferred oxygen sources include, but not limited to liquid oxygen storage tanks and / or vacuum swing adsorption (VSA) oxygen generator. Inside embodiment, oxygen from a liquid oxygen storage tank or VSA oxygen generator mixed with purified air, or pure nitrogen. When mixing oxygen with nitrogen Pure nitrogen can come from a liquid nitrogen tank or PSA nitrogen generator. Mass flow controllers (121), (123), (125) on the channel gas inlet is connected to the central process controller (131). Referring to the embodiment shown in Figure 1, the zone heat (107) has fewer gas outlets (129) then the preheating zone (105) and the cooling zone, (111) to increase the flow of furnace atmosphere from the hot zone to the adjacent zone. Preferably, most of the oxygen flows towards the front end of the furnace, in the direction in which the material is the cathode moves. This design facilitates the achievement of most of the atmosphere is rich in oxygen and little impurities in the hot zone of the furnace, where these parameters is the most critical. Oxygen sensors (133), (135), (137) are located on measurement points in the furnace. Preferred oxygen sensors are zirconia quartz, paramagnetic quartz, analyzer electrochemical or any other suitable oxygen sensor to measure oxygen in highly oxidizing atmospheres. Preferably, the oxygen sensors are positioned to measure the oxygen concentration in the atmosphere of each furnace zone. The oxygen sensors are preferably placed near a solid material that is heat treated to provide measurement of the atmosphere exposed to the material. In In practice, each zone will have more than one sensor. oxygen, and more than one set of other sensors, which are installed at different locations within the zone. The embodiment of shown in Figure 1, is given as an example where each zone has a set of sensors, to simplify image. This also applies to other types of sensors. In a embodiment, additional oxygen sensors (not shown) can be added and placed in the rich gas supply line main oxygen and main furnace outlet (ventilation) lines. The goal is to measure the oxygen concentration in the bloodstream. main supply and outlet lines (after the process calcination). Additional oxygen sensors are also connected with process controllers via wireless nodes or connections electricity directly to the process controller. The purpose of installing the sensor This is to measure the oxygen concentration before and after after the calcination process. This measurement will allow calculations to determine how much oxygen is used in the process and use this data for analysis process thermodynamics and improved process control. Referring to the embodiment of Figure 1, the first oxygen sensor (133) placed in the preheating zone (105) of the furnace, the sensor the second oxygen (135) is placed in the hot zone (107) of the furnace and the third oxygen sensor (137) is located in the cooling zone (111). Sensor nodes (139), (141), (143) for each zone receiving signals from oxygen sensors (133), (135), (137) and in turn relates to the process controller center (131). The main process controller can be equipped with cloud-based data recording system (132). In a embodiment (not shown) oxygen sensors located in the outside of the furnace in the sampling path, which is discussed in lower. More oxygen sensors can be added to the system. to measure oxygen concentration at other furnace locations, namely the gas supply line and the furnace ventilation line. Sensor- This sensor is connected to the process controller through a node wireless or direct electrical connection to the process controller. Sensors for measuring velocity and direction of flow (145), (147), (149) are placed in each zone preheating (105), heat (107) and cooling (111). Sensor- velocity and flow direction sensors (145), (147), (149) respectively electrically connected to nodes (139), (141), (143) for each zone, and the nodes are connected with central process controller. Sampling lines (151), (153), (155) placed in each preheating zone (105), heat (107) and cooling (111). Sampling routes allows atmospheric samples in each zone to be taken from the furnace to be analyzed by external sensors to measure the point dew and impurities. Part of each path sampling (151), (153), (155) stretches through the upper furnace wall, and has openings exposed to the the inside of the furnace. The inside is preferably made of ceramic materials. Other parts of the sampling line extending from the first section to the monitoring device array. External parts of the sampling line (157), (159), (161) it is preferably made of thermally conductive materials, including but it is not limited to stainless steel, so it can heated to avoid condensation in the intake line samples. Preferably all materials used in the line sampling compatible for use with oxygen and cleaned to suitable conditions. Pumps (175), (177), (179) are used to take samples. atmosphere through sampling lines (157), (159), (161) and towards the sensor circuit. Filters (163), (165), (167) are located on each sampling line to remove contaminants any particles in the sample. Dew point sensors (169), (171), (173) measure the point atmospheric dew samples. After the dew point analyzer, the cup condensation (181), (183), (185) removes moisture from samples before going to the CO2 analyzer (187), (189), (191) and sensor circuit (193), (195), (197). The sensor circuit preferably includes sensors for measuring pressure and Impurities include, but are limited to, ammonia, SOx and NOx. After passing through the sensor circuit (193), (195), (197), the sample disposed of (194), (196), (198) to a safe location. A node (139), (141), (143) for each furnace zone receive signals from sensor circuits (193), (195), (197), CO2 analyzer (187), (189), (191), dew point sensor (169), (171), (173), oxygen sensors (133), (135), (137) and flow sensors (145), (147), (149) for the furnace zone. Each node is associated with a central process controller. The central process controller receives and processes the signals. from all sensors and regulates the oxygen flow to each zone which interfaces with and controls the flow controller mass (121), (123), (125). Figure 2 provides an example of the implementation of the control logic. process (200) for individual furnace zones. Control measures can be done as a discrete sequence or as a loop continuous. It should be noted that the control logic (200) is an example of pure. There are many other control logics that could possibly be used. improve the performance of calcination furnaces for the manufacture of materials Ni-rich cathode. At the beginning of the sequence (202), a measurement is taken from the sensor oxygen (204), CO2 sensor (206) and dew point sensor (208). The measurements are then compared with the values ​​that have been set. The set value can be selected by the operator or can be selected and varied by the main process controller in response to readings from other zones to optimize atmospheric conditions in in the furnace. Figure 2 provides an example set point of one embodiment. to illustrate the present invention. In practice 1 of the present invention, This set point will vary and is chosen by an engineer. process. The set point is adjusted to the specific furnace design and specific processing applications. Set points will also vary between the furnace zones. In the embodiment illustrated in Figure 2 oxygen measurements are taken as partial pressure of oxygen (p02) and compared with the set point of 0.9 bar (210). When p02 is equal to or lower than 0.9 bar, controller the process will signal the oxygen mass flow controller to the zone to increase oxygen flow to zone (214). The system will continuously read oxygen measurements from the oxygen sensor. (204) until the reading is greater than 0.9 bar (210). As used here, 0.9 bar is equivalent to oxygen concentration of 908 based on oxygen volume, assuming a total furnace pressure of around 1 bar for make it easier.. The flow controller is preferably capable of proportional control that allows adjustments more accurate flow is proportional to the set point deviation. When the oxygen reading (210) is greater than the set point, in this case, 0.9 bar, the controller will then compare CO2 sensor measurement with predetermined values, in this is 50 ppm (212). If the CO2 concentration is equal to or greater than 50 ppm, the process controller will signal oxygen mass flow controller for the zone so that increase the flow of oxygen to zone (218). The system will continuously read carbon dioxide measurements from the sensor (206) until the increased oxygen flow has replaced Sufficient CO2 for readings below 50 ppm (212). When pO2 is above the set point and the CO2 reading is below the set point, in this case, 50 ppm, the controller will compare the dew point sensor measurement with the set point, in this case 0 degrees Celsius (216). When the dew point is the same with or greater than 0 degrees Celsius, the controller the process will signal the oxygen mass flow controller to the zone to increase oxygen flow to zone (222). The system will continuously read the dew point measurements from sensor (220) until the increased oxygen flow has been replace enough moisture for a reading below 0 degrees Celsius. When pO2 is above the set point and CO2 and CO2 measurements are taken dew point is below the set point, the controller will maintain oxygen flow to the zone. Closed loop control logic analog is used with sensor circuits for pressure and other impurities. The main process controller is configured with software to simultaneously monitor readings all sensors in each zone and to manipulate the controller mass flow to optimize the atmosphere inside the furnace. The set points for parameters in each zone may be different. and can be dynamically adjusted by the process controller primary in response to sensor measurements. Measurement of temperature and / or differential pressure can be carried out at various points. The measurements are on the flow Ventilation can indicate flow direction and flow rate. Measurement between the furnace and the ventilation flow, or between the two location of the furnace, can indicate the direction of flow and / or rate the same flow. Example Thermal Gravimetric Analysis (TGA) was performed on the precursors NMC (811) mixed with two lithium sources, lithium hydroxide (Li0H) and lithium carbonate (Li2C03) are used for the manufacture of cathode materials. This test is carried out to understand this chemical behavior under oxygen (oxidation reaction) and temperature to gain a better understanding about the decomposition of materials in temperature profiles. example 1 - NMC (811) and LiOH precursors. A total of 18.8070 mg of the NMC precursor mixture (811) and LiOH (molar ratio 1:1) was placed into the TGA instrument. (TGA 0500, TA Instrument, New Castle, Delaware). temperature increased from 50 degrees Celsius to 900 degrees Celsius in the atmosphere which consists of 98 percent by volume oxygen and 2 percent by volume nitrogen. The gas flow process (oxygen supply) is set to 50 ml / min. temperature held for 30 minutes at a temperature of 50 degrees Celsius, which followed by an increase in heating of 3 degrees Celsius per minute up to 900 degrees Celsius. Then the material is held at temperature of 900 degrees Celsius for 20 minutes. The ingredients then cooled to room temperature. The reaction is a furnace that uses L10OH as a Li source is AN10.8Mn0.1Co00.1044Li1OH t O2 Aa 4LiNi0.8Mn0.1Co0.10242H20. results- The results of example 1 are summarized in Table 1. Table 1 - TGA Analysis Results of NMC (811) and LiOH precursors Range of Number of Components- O Temperature (“C) Weight Loss | gas components that (Sberat) related to weight loss 167 to 10.40 H0 261 261 to 4.65 HO 459 459 to 1.38 HO 128 128 to 0 N / A 900 The results in Table 1 show that the removal of water from precursor materials occur gradually at temperatures that lower, before the material reaches the process temperature maximum 900 degrees Celsius example 2 - NMC (811) and Li2cC03 precursors A total of 33.9230 mg of a mixture of NMC (811) and L1i2C03 precursors (molar ratio 2:1) placed into the TGA apparatus (same as above). The ingredients are left to stand first room temperature for 30 minutes. The temperature is then raised from room temperature to 950 degrees Celsius at a rate of 3 degrees Celsius per minute. During the process the material is below 98 percent oxygen by volume in the atmosphere and 2 percent by volume of nitrogen, with a gas flow rate of 50 ml / min. The reaction in the furnace uses Li2C03 as Li source: 2N10.8Mn0.1Co0.10t2L12C03102 a 2L1N10.8Mn0.1Co0.10242CO2. The results of example 1 are summarized in Table 2. Table -2 - TGA Analysis Results of NMC (811) precursor and L12C03 Range of Number of Components- O Temperature (“C) The decrease in gas components that Weight (Sberat) is related to weight loss 167 to 1.18 H0 261 261 to 6.10 H»O, CO, 459 459 to 9.47 H»O, CO, 812 812 to 0 N / A 950 The results in Table 2 show that the removal of water from precursor materials occur gradually at temperatures that lower, before the material reaches the process temperature maximum 950 degrees Celsius. The present invention has been disclosed in the form of an embodiment which preferred and its alternative manifestations. Of course, various changes, modifications, and amendments to the teachings of this invention can be considered by those who are experts in their field without out of the spirit and scope of what was intended. This is it is intended that this invention is limited only by the conditions from the attached claim.

Claims

1. A furnace atmosphere control method for a calcination furnace for the manufacture of lithium ion battery cathode materials, the method consists of the following steps: (a) measure the first oxygen concentration, the concentration first humidity and first carbon dioxide concentration of atmosphere inside the first zone of the calcination furnace: (b) measure the second oxygen concentration, concentration second humidity and second carbon dioxide concentration of the atmosphere in the second zone of the calcination furnace, where the second zone bordering the first zone and the boundary between the first zone and secondly, it is located where the atmospheric temperature reaches a certain temperature predetermined immersion: (c) supplying oxygen process gas consisting of at least 50 percent oxygen by volume, in independent, to the first and second zones of the calcination furnace:j (d) controlling the flow rate of the first stream of process gas oxygen into the first zone as a function of the least amount one selected from group (i) oxygen concentration first measured in step (a), (11) concentration the first humidity measured in step (a), and (iii) the first carbon dioxide concentration measured in step (ad: (e) controlling the flow rate of both process gases oxygen into the second zone as a function of the least amount of one of the one selected from group (i) second oxygen concentration measured in step (b), (i1) the second moisture concentration measured in step (b), and (iii) carbon concentration second dioxide measured in step (b),: and (£) maintain the flow rate of the first stream of process gas oxygen at or below the flow rate of both process gases oxygen, to prevent the flow of gas from the first zone into the second zone.

2. The method according to claim 1, wherein step (d) further consists of increasing the flow rate of the first stream of process gas oxygen if at least one is selected from the group (1) the first oxygen concentration measured in step (a) less than the specified set point, (ii) concentration the first humidity measured in step (a) is greater than predetermined set point, and (iii) carbon concentration the first dioxide measured in step (a) is greater than predetermined set point.

3. The method according to claim 1, wherein step (e) further consists of increasing the flow rate of both process gases oxygen if at least one is selected from the group (1) the second oxygen concentration measured in step (b) less than the specified set point, (ii) concentration the second humidity measured in step (b) is greater than predetermined set point, and (iii) carbon concentration the second dioxide measured in step (b) is greater than the set predetermined points.

4. The method according to claim 1, further comprising: (h) repeat steps (a) to (£) all at once simultaneously heating, gradually, the first zone up to first temperature and maintain the second zone at the temperature second, where the second temperature is greater than or equal to first temperature.

5. The method according to claim 2, further comprising: (1) repeat steps (a) to (£) simultaneously simultaneously feeding a number of battery cathode precursor materials lithium ions into the first zone for a sufficient period of time to heat the material to the temperature of the material has been determined, then feed the material into second zone.

6. The method according to claim 1, further comprising: (J7) measures the third oxygen concentration, concentration third humidity and third carbon dioxide concentration of the atmosphere within the third temperature zone of the furnace, where the zone the third temperature zone borders the second temperature zone: (k) controlling the flow rate of the three process gases oxygen into the third zone as a function of the least one selected from group (i) oxygen concentration the third measured in step (J7), (ii) moisture concentration the third measured at step (jJ), and (iii) concentration third carbon dioxide measured in step (jJ): and (Ll) maintains the flow rate of the three process gases oxygen at or below the flow rate of both process gases oxygen, to prevent the flow of gas from the third zone into the second zone.

1. The method according to claim 5, wherein the lithium cathode precursor material ions are selected from a group consisting of precursors for: lithium nickel manganese cobalt (NMC): lithium nickel cobalt aluminum (NCA): lithium nickel manganese cobalt aluminum (NMCA) : Nickel Cobalt Boron (NCB) and its combinations.

8. The method according to claim 7, wherein the cathode precursor material includes a nickel mole ratio greater than 0.

5.

9. The method according to claim 1, wherein the oxygen process gas comprises purity of at least 90 percent by volume.

10. The method according to claim 1, further comprising: (m) remove a sample of the furnace atmosphere from the first zone through the sample path, and (n) sending samples to at least one analyzer externally configured to measure the parameters that selected from the group consisting of: oxygen concentration: carbon dioxide concentration, dew point, ammonia, SOx and Nox.

11. A furnace atmosphere control method for a calcination furnace for the manufacture of lithium ion battery cathode materials, the method consists of the following steps: (g) measuring the first atmospheric oxygen concentration in the atmosphere first zone of calcination furnace:j (h) measure the second oxygen concentration in the second zone calcination furnace, where the second zone borders the second zone first and the boundary between the first and second zones is located where atmospheric temperature reaches the immersion temperature that has been determined: (1) supplying oxygen process gas consisting of at least 50 percent oxygen by volume, in independent, to the first and second zones of the calcination furnace:j (J) control the flow rate of the first stream of process gas oxygen into the first zone as a function of oxygen concentration first measured in step (la): (k) controlling the flow rate of both process gases oxygen into the second zone as a function of oxygen concentration both measured in step (b): and (1) maintain the flow rate of both process gases oxygen at or below the first flow rate of the process gas stream oxygen, to prevent the flow of gas from the second zone into the second zone. First.

12. A device for controlling the atmosphere in a section in a calcination furnace for the manufacture of battery cathode materials solid state or lithium ion consisting of: the first group of sensors, which are installed in the temperature zone first furnace, the first sensor group consisting of sensors first oxygen, first humidity sensor and carbon sensor first dioxide: the second group of sensors, which are installed in the temperature zone second furnace, the second sensor group consisting of sensors second oxygen, second humidity sensor and carbon sensor second dioxide: a custom-configured oxygen delivery system operationally placed fluidly connected to the source oxygen to deliver independently the oxygen flow that set to the first and second furnace temperature zones, process controllers are operationally configured to related to sensors and oxygen delivery systems to control the rate of oxygen delivery to the temperature zone first and second in response to signals from first and second sensor groups.

13. The apparatus according to claim 12, further comprising a path first operationally configured sampling to extract atmospheric samples from within the temperature zone first the furnace and sends it to the first external sensor: the first external sensor is operationally configured to related to process control.

14. The apparatus according to claim 12, wherein the first oxygen sensor is an in-situ sensor.

15. The apparatus according to claim 12, wherein the first external sensor is a sensor for measuring selected parameters from group consisting of: oxygen, pressure, dew point, carbon dioxide, ammonia, SOx, NOx and differential pressure.

16. The apparatus according to claim 13, wherein the sampling path The first includes a dehumidifying device that operationally configured to remove moisture from furnace atmosphere samples.

17. The apparatus according to claim 12, wherein the first furnace zone covers the upper and lower areas: sensors The first oxygen is placed in the upper area and the respiratory tract inlet configured to drain oxygen from the system oxygen delivery is placed in the lower area.

18. The apparatus according to claim 13, wherein the sampling path first passed through the furnace wall: the intake path sample consisting of an interior length formed from ceramic material and placed on the inside of the furnace wall, and the length of the exterior is formed from stainless steel and placed on the outside of the furnace wall.

19. The apparatus according to claim 14 wherein the first sensor group and the first external sensor is operationally configured to connect with the first sensor node, the sensor node first operationally configured to connect with process controller.

20. The apparatus according to claim 12 wherein the first sensor group next consists of the first gas flow velocity sensor and The second sensor group consists of gas flow sensors. second.

Images