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GB/T 38823-2020 English PDF
GB/T 38823-2020 NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 29.050 Q 50 Silicon-carbon 硅炭 ISSUED ON: JUNE 02, 2020 IMPLEMENTED ON: DECEMBER 01, 2020 Issued by: State Administration for Market Regulation; Standardization Administration of the PRC. Table of Contents Foreword ... 3 1 Scope ... 4 2 Normative references ... 4 3 Terms and definitions ... 5 4 Classification and code ... 5 5 Technical requirements ... 6 5.1 Appearance ... 6 5.2 Physical and chemical indicators ... 6 6 Test methods ... 7 6.1 Appearance ... 7 6.2 Particle size distribution ... 7 6.3 Specific surface area ... 7 6.4 Tap density ... 7 6.5 Carbon content ... 7 6.6 Silicon content ... 7 6.7 Compaction density ... 7 6.8 Moisture content ... 7 6.9 Magnetic impurities ... 7 6.10 Content of trace metal elements ... 7 6.11 Initial discharge specific capacity and initial coulombic efficiency ... 7 6.12 Regulated substances ... 7 7 Inspection rules ... 8 7.1 Sampling method ... 8 7.2 Inspection classification ... 8 7.3 Acceptance rules ... 9 8 Packaging, marking, storage, and transportation ... 9 8.1 Packaging ... 9 8.2 Marking ... 9 8.3 Storage and transportation ... 10 Appendix A (Normative) Determination method of carbon content ... 11 Appendix B (Normative) Determination method of silicon content ... 14 Appendix C (Normative) Determination method for the content of trace metal elements ... 17 Appendix D (Normative) Determination method of initial discharge specific capacity and initial coulombic efficiency ... 20 Silicon-carbon 1 Scope This Standard specifies the terms and definitions, classification and code, technical requirements, test methods, inspection rules, packaging, marking, transportation, and storage of silicon-carbon. This Standard applies to all kinds of silicon-carbon anode materials for lithium-ion batteries. 2 Normative references The following documents are indispensable for the application of this document. For the dated references, only the editions with the dates indicated are applicable to this document. For the undated references, the latest edition (including all the amendments) are applicable to this document. GB/T 191 Packaging - Pictorial marking for handling of goods GB/T 2828.1 Sampling procedures for inspection by attributes - Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection GB/T 2829 Sampling procedures and tables for periodic inspection by attributes (apply to inspection of process stability) GB/T 3782 Acetylene black GB/T 4369 Lithium GB/T 5187 Copper and copper alloy foil GB/T 6388 Transport package shipping mark GB/T 6682 Water for analytical laboratory use - Specification and test methods GB/T 8170 Rules of rounding off for numerical values and expression and judgement of limiting values GB/T 13732 General rules for sampling inspection of bulk materials with uniform size GB/T 19077 Particle size analysis - Laser diffraction methods GB/T 19587 Determination of the specific surface area of solids by gas adsorption using the BET method GB/T 21653 Nickel and Nickel-alloy Wire and Drawing Stock GB/T 24533 Graphite negative electrode materials for lithium ion battery GB/T 26125 Electrical and electronic products - Determination of six regulated substances (lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls, polybrominated diphenyl ethers) GB/T 33827 Determination of magnetic impurities in anode nanomaterials for Li- ion battery 3 Terms and definitions The following term and definition applies to this document. 3.1 Silicon-carbon Composite powder material composed of silicon material and carbon material. The synergistic effect of silicon-carbon and cathode materials in a certain system can realize multiple charging and discharging of lithium-ion batteries. During the charging process, the silicon-carbon negative electrode accepts the intercalation of lithium ions. During the discharging process, the lithium ions are extracted. 4 Classification and code The products are classified according to their initial discharge specific capacity; mainly divided into five categories: - 400 mAh/g ≤ initial discharge specific capacity< 600 mAh/g; represented by SiC-I; - 600 mAh/g ≤ initial discharge specific capacity< 900 mAh/g; represented by SiC- Ⅱ; - 900 mAh/g ≤ initial discharge specific capacity< 1200 mAh/g; represented by SiC- Ⅲ; - 1200 mAh/g ≤ initial discharge specific capacity< 1500 mAh/g; represented by SiC- IV; - Initial discharge specific capacity≥1500 mAh/g; represented by SiC-V. 7 Inspection rules 7.1 Sampling method 7.1.1 Sampling Silicon-carbon is sampled according to GB/T 13732 “General rules for sampling inspection of bulk materials with uniform size”. Insert a clean sampling drill (stainless steel designation 316 or equivalent; diameter: no more than 30 mm) into the package along the axis. The insertion depth must not be less than 4/5 of the package. Take samples within 20 mm around the center axis of the material in the package. Sampling is carried out in accordance with the relevant provisions on sampling in GB/T 2828.1 and GB/T 2829. 7.1.2 Sample label After the sample is placed in the plastic sample jar, a label shall be attached to the outer wall. The label shall include the following: a) Sample category and number; b) Overall material lot number and quantity; c) Sample size; d) Sampling date; e) Name of sampler. 7.1.3 Storage of samples The samples shall be sealed and stored in an environment protected from bag break, rain and moisture. The effective storage period of spare samples is 12 months. 7.2 Inspection classification 7.2.1 Exit-factory inspection Inspect the specific surface area, tap density, compaction density, silicon content, magnetic impurities, trace metal elements, 0.1 C initial discharge specific capacity, 0.1 C initial coulombic efficiency, and regulated substance content of each lot. After passing the inspection, stamp the quality inspection seal. 7.2.2 Type inspection Inspect all technical requirements specified in this Standard. Type inspection is carried out in one of the following situations: a) When the model and supplier of raw materials are changed; b) When there is a change in the production technology process; c) When the production equipment has been shut down for more than half a year and starts production again; d) When customers have special requirements; e) Under normal circumstances, the type inspection shall be conducted at least once a year. 7.3 Acceptance rules 7.3.1 Products that meet the requirements of technical indicators in Table 1 are conformity products. If there is 1 indicator that fails to meet the requirements of the standard, double number of samples shall be taken from the sampling bag of the same lot of products, to re-inspect the nonconformity item. If all the re-inspections are conformity, it will be judged as conformity. If one item is nonconformity, it will be judged as nonconformity. 7.3.2 The manufacturer shall ensure that, the products that leave the factory meet the requirements of this Standard. When leaving the factory, each lot of products is accompanied with an inspection report. 7.3.3 The re-inspection period of the receiving party is 2 months. If there is any objection, it shall take double number of samples for re-inspection. If there is still a dispute, it will be inspected by a qualified third-party testing agency. 8 Packaging, marking, storage, and transportation 8.1 Packaging 8.1.1 The packaging of the product shall comply with the provisions of GB/T 191. The net weight shall be negotiated by both the supplier and the purchaser. 8.1.2 The packaging shall be carried out in a dry environment. The product shall be first put into a waterproof packaging bag (PE sealing bag and aluminum-plastic sealing bag are recommended). Special packaging requirements are negotiated by both the supplier and the purchaser. 8.1.3 The packaged products are then packaged with outer packaging materials. The packaging materials are negotiated by both the supplier and the purchaser. 8.2 Marking The marking shall comply with the provisions of GB/T 6388. It shall generally include Appendix A (Normative) Determination method of carbon content A.1 Method summary Combustion in an oxygen stream converts carbon to carbon monoxide and/or carbon dioxide. Carbon monoxide is catalytically oxidized to carbon dioxide at high temperatures. Use the infrared absorption spectrum of carbon dioxide in the oxygen stream for the measurement. A.2 Instruments and equipment A.2.1 High-frequency infrared carbon-sulfur analyzer or carbon determinator. It consists of an infrared source, an independent measuring cell, and a reference cell, etc. A.2.2 Dryer. A.2.3 Electronic balance: The sensitivity is 0.0001 g. A.2.4 Porcelain crucible, according to the regulations of the instrument manufacturer, can withstand combustion in a high-frequency induction furnace and does not produce carbon chemicals. The blank value is less than 0.002%. The standard deviation is less than 0.0005%. Note: Carbon pollutants can usually be removed by burning the crucible in a muffle furnace in the air. The burning time at 1000 ℃ is not less than 40 min. The burning time at 1350 ℃ is not less than 15 min. Then take out the crucible; put it in a clean heat-resistant plate; cool it for 2 min~3 min; finally store the crucible in a dryer. A.2.5 Crucible tongs, which can hold the porcelain crucible (see A.2.4). A.3 Analytical procedure WARNING - The main hazard associated with combustion analysis is the combustion that occurs when the crucible is burned and during the resulting molten state. Use crucible tongs at all times; store used crucibles in suitable containers. Be careful when opening t...... Similar standards: GB/T 32151.34-2024 GB/T 42241-2022 Similar PDFs (Auto-delivered in 9 seconds): GB/T 38823-2020 GB/T 37588-2019 GB/T 40398.1-2021 GB/T 40398.2-2021 |
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