First, the electrode composition: 1, cathode comprising: a, cobalt acid lithium: live * cathode material, lithium-ion source, in order to improve laptop battery source. b, conductive agents: improve cathode conductive films *, compensation cathode material live * * electronic conductivity. Cathode films enhance absorption of liquid electrolyte, an increase of reaction interface to reduce polarization. c, PVDF binder: will cobalt acid lithium, conductive agents and aluminum foil or aluminum net bonded together. d, cathode lead: made from aluminum foil or aluminum strip. 2, negative electrode composed of: a, graphite: Negative live * substances, constitutes a negative reaction of the main substances; mainly divided into natural graphite and artificial Graphite two broad categories. b, conductive agents: improve cathode conductive films *, compensation anode material live * * electronic conductivity. Depth and improve the utilization rate of reaction. To prevent the emergence of dendrites. The use of conductive material liquid absorption capacity, improve reaction interface, reducing the polarization. (Available under the graphite particle size distribution with or without choice). c, additives: Reduce non-reversible reaction, improve adhesion, improve slurry viscosity, slurry to prevent precipitation. d, water * Adhesives: The graphite, conductive agents, additives and copper foil or copper mesh bonded together. e, cathode lead: from copper or nickel belt made. Second, the ingredients Objective: Batching process is in reality all kinds of slurry composition in accordance with the standard mixing ratio, modulation into a slurry, in order to facilitate uniform coating to ensure the most consistent * tablets. Ingredients generally includes five processes, namely: pre-processing of raw materials, mixing, wetting, dispersion and flocculation. Three, the principle ingredients: (1), the principle ingredient cathode 1, * physical and chemical raw materials to. (1) Cobalt Lithium: * non-polar substances, irregular shape, particle size D50 is generally 6-8 μm, water content ≤ 0.2%, usually alkali *, PH value is around 10-11. Lithium Manganese: * non-polar substances, irregular shape, particle size D50 is generally 5-7 μm, water content ≤ 0.2%, usually weak base *, PH value is around 8. (2) conductive agent: * non-polar substances, grape-like chain, 3-6% moisture content, oil absorption value of ~ 300, particle size is generally 2-5 μm; mainly ordinary carbon black, super-conducting carbon black,Latitude D600 ,Latitude D610 , Latitude D620 , Latitude D820 , graphite milk and so on, in high-volume applications typically choose superconducting carbon black and graphite milk mixture; usually * Medium. (3) PVDF binder: * non-polar substances, chain-like molecular weight ranging from 300,000 to 3,000,000; water decreased after the molecular weight, viscosity * variation. (4) NMP: Weak extremely * liquid, used for dissolving / swelling PVDF, also used to dilute the slurry. 2, the pretreatment of raw materials (1) Cobalt Lithium: dehydration. The general atmospheric pressure baking with 120 oC for about two hours. (2) conductive agent: dehydration. The general atmospheric pressure baking with 200 oC for about two hours. (3) adhesive: dehydration. 120-140 oC atmospheric pressure tends to be used 2 hours baking, baking temperature depending on the size of molecular weight of the decision. (4) NMP: dehydration. The use of dry molecular sieve dehydration or special Reclaimer facilities, direct use. 3, the blending of raw materials: (1) binder dissolved (in accordance with the standard concentration) and heat treatment. (2) and conductivity of lithium cobalt acid milling agent: so that the initial mixed powder, cobalt acid lithium and conductive bonding agent together, to reunite the role and improve the electrical conductivity *. Pair will not separate the distribution of slurry in the adhesives, the milling time is generally about two hours; in order to avoid mixing with impurities, normally used as agate ball milling meson. 4, dry powder dispersion, wet: (1) Principle: solid powder placed in the air, over time, will be part of the air in solid adsorption of the surface, add the liquid adhesive, the liquid and gas began to compete for solid surface; if the solids and gas adsorption than strong adsorption and liquid, liquid should not wet solids; if the adsorption of solids and liquids than with gases and strong adsorption, the liquid can wet solids, the gas extrusion. When the wetting angle ≤ 90 degrees, solid wet. When the contact angle> 90 degrees, solid is not wet. Cathode materials for all team members can be wet adhesive solution, it is relatively easy to cathode powder dispersion. (2) dispersion method of the impact of decentralization: A, standing law (a long time and poor performance, but does not damage the material of the original structure); B, mixing method; rotation, or rotation plus revolution (time is short, the effect of good, but there may be individual injury Material for their own structure). 1, impeller speed on the impact of decentralization. Impeller broadly include the snake-like, butterfly, spherical, paddle-shaped gear-shaped and so on. General snake, Inspiron 1300 , Inspiron 1501 , Inspiron 1520 , butterfly, propeller-type impeller used against dispersed difficult material or ingredients of the initial phase; spherical gear dispersed the difficulty for the lower state, the effect of good. 2, stirring speed on the speed of the impact of decentralization. Generally speaking the higher the stirring speed, the faster the dispersion, but on the material their own structure and the equipment the greater the damage. 3, concentration on the dispersion velocity. Usually the smaller the slurry concentration, the faster the spread, but is too thin will result in material waste and slurry heavier precipitation. 4, concentration on the impact of bond strength. Greater concentration, flexible system for the greater strength, bonding strength Greater; concentration the lower the smaller the bond strength. 5, vacuum the speed of the impact of decentralization. High vacuum gap in favor of materials and surface gas emissions, reducing the difficulty of liquid adsorption; material in complete weightlessness or reduced gravity dispersed evenly circumstances would significantly reduce the difficulty. 6, temperature of the dispersion velocity. Appropriate temperature, the slurry flows * good, easy to spread. Hot slurry crust easily, too cold slurry flow * will be greatly reduced. 7, diluted. The slurry adjusted to a suitable concentration, to facilitate coating. (B), the principle of negative ingredients (broadly in line with the same principle as cathode ingredients) 1, * physical and chemical raw materials to. (1) graphite: * non-polar substances, the vulnerability of non-polar substances pollution * easy * in non-polar substances dispersed; less water and are not easy dispersion in water. Contaminated graphite, dispersed in water, the easy re-reunion. D50 for the general size of about 20μm. Particle shape many diverse and irregular, mainly spherical, flake, fibrous and so on. (2) water * Adhesives (SBR): small-molecule line * Chain emulsion, easily soluble in water and polar solvents *. (3) The anti-precipitating agent (CMC): high-molecular compound, soluble in water and polar solvents *. (4) isopropanol: Weak extremely * material, add adhesive solution can be reduced very *, graphite and improve the compatibility of adhesive solution *; have a strong anti-foaming effect; easy catalytic adhesive mesh Alternaria , improve bond strength. Ethanol: very * weak material, add adhesive solution can be reduced very *, graphite and improve the compatibility of adhesive solution *; have a strong anti-foaming effect; easy catalytic Adhesives Line * Alternaria, improve bond strength (the role of isopropyl alcohol and ethanol are essentially the same, high-volume production cost factors to be taken into account and then choose what to add). (5) deionized water (or distilled water): diluent, add slightly to change the flow of slurry *. 2, the pretreatment of raw materials: (1) Graphite: A, mixed, so that homogenization of raw materials, improve consistency *. B, 300 ~ 400 ℃ Atmospheric baking, remove the surface oil * substances, and water * improve the compatibility of adhesive ability to repair the surface of graphite round edges and corners (some material in order to maintain the surface of special *, baking is not allowed, otherwise, performance degradation ). (2) water * Adhesives: appropriate dilution, dispersion ability to improve. 3, mixing, wetting and dispersion: (1) graphite with adhesive solution very * different, not easily dispersed. (2) can be used alcohols in aqueous solution will be the initial wetting of graphite, and then mixed with the binder solution. (3) should be appropriate to reduce the concentration of mixing, dispersion * improve. (4) decentralization process in order to reduce a very * very * complex and non-object distance, improve the potential energy or surface energy, so for the endothermic reaction, stirring when the temperature has decreased overall. Permit conditions such as mixing temperature should be appropriately increased so that endothermic easier, at the same time improve mobility *, lower dispersion degree of difficulty. (5) mixing process such as add a vacuum degassing process, excluded gas, ThinkPad T43 , 40Y6797 , 40Y6799 , ASM 92P1138 , the promotion of solid - liquid adsorption, the effect better. (6) the principle of decentralized, distributed approach with cathode ingredients of relevant content, in three, (1), 4 in detail, in this not explained in detail. 4, diluted. The slurry adjusted to a suitable concentration, to facilitate coating. IV ingredients NOTES:
1, to prevent mixing with other impurities;
2, to prevent slurry spatter;
3, the concentration of slurry (solid content) from the high to low adjust gradually to avoid increasing the trouble;
4, in the mixing of the batch process, attention should be paid at the end of scraping edges and scraping to ensure uniform dispersion;
5, slurry should not be a long time on hold in order to avoid precipitation or even * lower;
6, to be baking the material must be sealed after cooling can add in order to avoid changes in component materials * quality;
7, the length of mixing equipment * can, add the volume of the main materials; the use of impeller slurry dispersed to the difficulty of replacement, can not be replaced by the slow speed can be adjusted to fast so as not to damage equipment;
8, before the slurry material to carry out screening to remove large particles caused coating to prevent the belt; Nine of ingredients to enhance the training of personnel to ensure that they master the professional knowledge, so as not to result in serious accidents; 10, the key is to spread the ingredients evenly, master of the Center, are free to adjust in other ways. V. Introduction: With the battery manufacturing process increasingly transparent, lithium-ion battery manufacturers increasingly will be the core ingredients classified as confidential, because from the material selection, to a reasonable deal with too many technical staff includes painstaking efforts, the same material Some manufacturers use them particularly successful, some 100 manufacturers on the trouble; Some manufacturers use the material can be made mid-range high-end batteries ASM 92P1140 , ThinkPad R51 , ThinkPad T40 , while some manufacturers are using the best materials had led to appalling battery.
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