KR-20260066005-A - DYNAMIC CONTROL AND PERFORMANCE ASSESSMENT/OPTIMIZATION OF SECONDARY BATTERY CELL FINISHING (FORMATION/AGING/SORTING/GRADING) UTILIZING SIMULTANTEOUS INLINE ELECTROCHEMICAL METHODS AND CLOSED-LOOP PROCESS CONTROL

Abstract

Control, evaluation, and optimization techniques for manufacturing secondary electrochemical devices to improve the quality, throughput, and safety of cells produced and to facilitate the finishing (forming/aging/sorting/grading) process. A system for dynamic control and optimization of the secondary battery finishing process includes a closed-loop process control module configured to process real-time in-line manufacturing data derived from at least one of electrochemical impedance spectroscopy (EIS), self-discharge analysis (SDA), ammeter, or potentiometer battery measurements. Cell forming can be reduced from several days using conventional technology to less than 24 hours, and aging can be reduced from 2-3 weeks to less than 1 hour. The control module provides real-time feedback on preceding operations/materials for verifications, improvements, corrections, and/or recognition or isolation of better/worse performance characteristics. The control module also provides feedforward information of recognized aspects that can represent performance deviations from the norm.

Inventors

• 노이츨러, 제이 케빈
• 웨스터버그, 칼 프레드릭
• 팔존, 알렉 제이콥
• 하리하란, 스리라마

Assignees

• 허니웰 인터내셔날 인코포레이티드

Dates

Publication Date

20260512

Application Date

20260406

Priority Date

20230706

Claims (5)

1. A system for dynamic control and optimization of a secondary battery cell closing process including a closed-loop process control module, wherein the closed-loop process control module comprises: Receiving one or more in-line real-time process parameters related to a secondary battery derived from at least one of electrochemical impedance spectroscopy (EIS), self-discharge analysis (SDA), ammeter or potentiometer battery measurements from the above secondary battery cell closing process, and It is configured to determine the deviation of the in-line real-time process parameters by comparing the in-line real-time process parameters associated with one or more secondary batteries against a corresponding set of pre-selected values, and A system further configured such that, in response to deviations in the in-line real-time process parameters, the closed-loop process control module controls the charging and discharging of the one or more secondary batteries during the formation of the solid electrolyte interface (SEI) of the anode in the one or more secondary batteries and the cathode electrolyte interface (CEI) of the cathode in the one or more secondary batteries.
2. In paragraph 1, the charging and discharging of the one or more secondary batteries is, Executing a charging protocol or a discharging protocol for one or more of the above secondary batteries; Terminating the charging or discharging of one or more of the above secondary batteries; or Implementing an alternative charging protocol or discharging protocol for one or more of the above secondary batteries A system controlled by performing at least one of the following.
3. In claim 1, the in-line real-time process parameter is selected from the group consisting of ohmic resistance (R Ω ), charge transfer resistance (R ct ), leakage current (I leak ), open circuit voltage (OCV), voltage drop (ΔV), and combinations thereof, in a system.
4. A system for controlling a secondary battery cell closing process including a closed-loop process control module, wherein the closed-loop process control module comprises: Processing in-line real-time process parameters related to one or more secondary batteries from charge/discharge functions, electrochemical impedance spectroscopy (EIS) measurements, self-discharge analysis (SDA) measurements, ammeter measurements and/or potentiometer measurements, and By comparing the above in-line real-time process parameters with the norm, deviations in the battery performance of one or more secondary batteries are identified from the norm, and Identifying historical battery manufacturing operation conditions that potentially contribute to deviations in battery performance from the above norm, and A system configured to automatically adjust one or more production parameters of a secondary battery cell finishing process based on identified historical battery manufacturing operation conditions and identified deviations to reduce deviations in the battery performance of one or more secondary batteries.
5. In claim 4, the deviation in battery performance is determined from at least one of (i) statistical analysis of the in-line real-time process parameters, (ii) comparison of the rate of change of the in-line real-time process parameters and the norm, (iii) data extraction (dQ/dV), (iv) machine learning, and (v) artificial intelligence.

Description

Dynamic Control and Performance Assessment/Optimization of Secondary Battery Cell Finishing (Formation/Aging/Sorting/Grading) Using Simultaneous Inline Electrochemical Methods and Closed-Loop Process Control The present invention relates generally to the manufacture of electrochemical batteries, and more specifically to control, evaluation, and optimization techniques for improving the quality, throughput, and safety of secondary batteries, such as lithium-ion cells, in the finishing process. A lithium-ion cell is a type of secondary battery and comprises four main parts: a positive electrode (cathode), a negative electrode (anode), a separator placed between the electrodes to prevent contact and short circuits, and an electrolyte. Examples of cathode active materials may include, but are not limited to, mixed-metal oxides, metal phosphates, or related materials. Examples of anode materials may include, but are not limited to, graphite, silicon, or composites thereof. The electrolyte provides transport of ions and may be a liquid, solid, or liquefied gas. Battery manufacturing begins with the production of large sheets of double-sided coated anode copper substrates and double-sided coated cathode aluminum substrates. The electrodes are manufactured by a continuous roll-to-roll process in which a pre-mixed anode or cathode material is coated onto a sheet of metal substrate that functions as a current collector. The electrode sheets are cut into double-sided coated metal substrates of appropriate size. There are two main methods for constructing individual cells. One method is to wind the electrodes and separators into a "jelly roll" cell, and the other is to stack separate electrode sheets between each electrode or combine them with a separator film having a z-fold. Cylindrical and some prismatic cells are wound on a rotary machine supplied with rolls of anode and cathode electrodes and two rolls of separator film. For pouch cells and some prismatic cells, robotic arms are used to alternate anode and cathode stacks as the separator film is unwound from overhead to interlace the stacks completed by the rotation of the separator film. Lithium-ion cells are assembled in an uncharged state. The first charge or formation of the cell is critical to the expected cycle life and energy capacity. This involves multiple stages designed with rate, duration, and current/voltage limits for each stage to form a metastable passivation layer, referred to as the solid electrolyte interface (SEI) layer on the anode. Forming the SEI layer consumes some of the available lithium within the cell, which is a byproduct of electrolyte decomposition. Similarly, a cathode electrolyte interface (CEI) also occurs, providing uniform passivation to the anode. This CEI layer provides for maintaining ion transport pathways while suppressing undesirable side reactions between the anode particles and the electrolyte. However, regarding the anode SEI, forming an SEI layer that is too thin or/or non-uniform can cause electrolyte ions to flow into the anode material, which can increase the risk of lithium plating and/or lithium dendrite growth and reduce the cell's cycle life. Creating an appropriate SEI layer thickness is one of the critical process parameters in the cell production process, more specifically in the cell finishing area. Cell finishing operations also include degassing, which is a result of the formation process, and cell aging, which involves screening out cells with unacceptable levels of self-discharge. Since defective cells can catch fire when first charged, potentially leading to a rapid failure known as "thermal runaway," forming and aging processes are separated from the rest of the production process. Due to the long duration required to perform forming and aging processes, which typically take more than three weeks, these processes usually occupy the largest area in the factory, represent a significant inventory in progress, and consume approximately 40% of the capital expenditures required for major factory projects. Currently, the forming and aging of lithium-ion cells are performed following static recipes that are not controlled during each process, based on real-time observations. In particular, closing involves forming functions for charge/discharge to "form" the solid electrode/electrolyte interface (SEI) for the CEI cathode and anode. Closing is a long and critical process that significantly impacts cell longevity. Closing can take at least 24 to 48 hours and requires substantial space in racks, power electronics, energy, and process-in-process inventory. The process of aging battery cells takes much longer, taking 2 to 3 weeks. The aging process also requires significant floor space to stage and store the cells. Determining ΔOCV, or voltage drop, is a common test to determine cell quality and the final grade of the cells. A major drawback of this approach is that delays prevent timely quality feedback for correc