CN109950505B - Lithium titanate battery slurry and preparation method thereof - Google Patents
Lithium titanate battery slurry and preparation method thereof Download PDFInfo
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Abstract
The invention discloses lithium titanate battery slurry which is prepared from the following raw materials in parts by weight: 58-68 parts of lithium titanate, 3-8 parts of acetylene black, 3-5 parts of Keqin black, 10-15 parts of active substances, 12-16 parts of modified epoxy resin adhesive and 75-85 parts of 20% dimethyl sulfoxide aqueous solution; the invention also discloses a preparation method of the lithium titanate battery slurry; the lithium titanate battery slurry is prepared by taking lithium titanate, acetylene black, an active substance, modified epoxy resin glue and the like as raw materials, wherein the acetylene black and the Ketjen black are used as conductive agents, both the acetylene black and the Ketjen black exist in a nano form, and have unique branched chain structures and excellent conductive performance.
Description
Technical Field
The invention belongs to the technical field of lithium batteries, and particularly relates to lithium titanate battery slurry and a preparation method thereof.
Background
With the increasing popularization of electric vehicles, the demand of lithium ion batteries is increasing, and the safety, cycle life, quick charging and other performances of the current power batteries need to be greatly improved. Most of commercial lithium ion batteries adopt graphite cathode materials, but the graphite cathode materials have some disadvantages, such as easy formation of lithium dendrites during overcharge, battery short circuit and potential safety hazard. In addition, the graphite material platform is low, so that the problems of electrolyte decomposition and co-intercalation are easily caused, the cycle performance of the battery is reduced, the high-rate quick charging cannot be realized, and the like.
Lithium titanate has the lithium potential of about 1.55V, lithium dendrite is not easy to generate, and the safety performance is better; the lithium titanate is a zero-strain material, has excellent cycle performance and has a service life far longer than that of a graphite cathode; the lithium ion diffusion coefficient of the lithium titanate is one order of magnitude larger than that of the graphite cathode, so that the battery can realize rapid charge and discharge. Therefore, the lithium titanate battery has great commercial application prospect as a power battery. However, lithium titanate belongs to a nano-grade material, has large specific surface area and poor dispersibility, and is difficult to prepare uniform slurry according to the traditional slurry preparation method, so that the pole piece has poor coating effect and more particles, thereby influencing the cycle performance and rate capability of the lithium titanate battery.
The chinese patent CN107681109A discloses a lithium titanate battery slurry, which comprises a solute and a solvent, wherein the solute comprises the following raw materials by weight: 89-92% of lithium titanate, conductive agent SP 4%, conductive agent CNT 1-2%, and binder PVDF 3-5%. The invention also discloses a preparation method of the lithium titanate battery slurry. According to the invention, the content of the PVDF binder is adjusted, the PVDF binder is matched with the lithium titanate, the SP conductive agent and the CNT in a proper proportion to obtain a proper formula, and a proper slurry mixing process is combined, so that the problem of overlarge viscosity in the slurry mixing process can be effectively solved, the viscosity of the composite material is reduced from 6000-ion 8000 to 2000-ion 4000, the coating capability of the composite material is greatly improved, and the rate capability of a battery is improved; the invention has simple operation. However, the lithium titanate battery slurry prepared by the invention has low viscosity but still has poor coating effect, and the lithium titanate battery has poor performance when used under high rate.
Disclosure of Invention
In order to overcome the technical problems, the invention provides lithium titanate battery slurry and a preparation method thereof; the lithium titanate battery slurry is prepared by taking lithium titanate, acetylene black, an active substance, a modified epoxy resin adhesive and the like as raw materials, wherein the acetylene black and the Ketjen black are used as conductive agents, both the acetylene black and the Ketjen black exist in a nano form, and have unique branched chain structures and excellent conductive performance; the carboxyl-terminated polyether is prepared from polypropylene glycol and phthalic anhydride, the carboxyl-terminated polyether has low viscosity and contains flexible molecular chains, epoxy resin can be subjected to primary toughening, and then the performance of the epoxy resin is improved by adding fluororubber through ball milling, heating and other modes.
The purpose of the invention can be realized by the following technical scheme:
a lithium titanate battery slurry is prepared from the following raw materials in parts by weight: 58-68 parts of lithium titanate, 3-8 parts of acetylene black, 3-5 parts of Keqin black, 10-15 parts of active substances, 12-16 parts of modified epoxy resin adhesive and 75-85 parts of 20% dimethyl sulfoxide aqueous solution;
the high-efficiency lithium titanate battery slurry is prepared by the following method:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin glue, wherein the heating temperature of the lithium titanate and the modified epoxy resin glue is controlled to be 120 ℃, the pressure of the lithium titanate and the modified epoxy resin glue is controlled to be-0.10 MPa, the heating time is controlled to be 20h, the heating temperature of the acetylene black and the Ketjen black is controlled to be 160 ℃, the pressure of the acetylene black and the Ketjen black is controlled to be-0.07 MPa, the heating time is controlled to be 25h, and the lithium titanate, the acetylene black, the Ketjen black and the modified epoxy resin glue are taken out and kept stand for 2h after the heating treatment is finished;
step S2, adding the modified epoxy resin adhesive and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S1, adding active substances and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa & S to obtain premixed slurry;
And step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
Further, the modified epoxy resin adhesive is prepared from the following raw materials in parts by weight: 8-15 parts of polypropylene glycol, 12-20 parts of phthalic anhydride, 18-35 parts of bisphenol A, 24-32 parts of epoxy chloroethane, 18-30 parts of benzene, 5-13 parts of 10% sodium hydroxide solution, 3-5 parts of polyvinylpyrrolidone and 8-15 parts of fluororubber.
Further, the modified epoxy resin adhesive is prepared by the following method:
(1) adding bisphenol A into a dissolving kettle, adding epoxy chloroethane and benzene, stirring at a constant speed, heating to 75 ℃, stirring for 30min, transferring into a reaction kettle, adding 10% sodium hydroxide solution, heating to 45 ℃, stirring at a constant speed for 2h, filtering, standing, pumping the benzene solution into a refluxing benzene kettle, refluxing until no water drop appears in the evaporated benzene, standing and cooling for 45min, transferring into a debenzolization kettle, reducing the pressure at 135 ℃ until no distillate appears, taking out, and drying to obtain epoxy resin;
(2) adding polypropylene glycol into a three-neck flask, heating to 110 ℃, performing vacuum dehydration for 2h, adding phthalic anhydride, heating to 150 ℃, reacting for 5h at the temperature to obtain carboxyl-terminated polyether, taking out, mixing with epoxy resin in a beaker, heating to 85 ℃ until the carboxyl-terminated polyether is molten, adding polyvinylpyrrolidone after uniformly stirring, reacting for 3h, taking out, and standing for 1h to obtain a mixture;
(3) Mixing the fluororubber and the mixture, pouring the mixture into a ball mill, carrying out high-speed ball milling at the rotating speed of 1600r/min, adding the mixture into a beaker filled with 100mL of absolute ethyl alcohol after the ball milling is finished, carrying out ultrasonic treatment for 30min, extracting air in the mixed solution, transferring the mixture into a vacuum drying oven, controlling the vacuum degree to be 0.09MPa and the temperature to be 65 ℃, and drying for 12h to obtain the modified epoxy resin adhesive.
According to the invention, bisphenol A and epoxy chloroethane are used as raw materials, benzene is used as a solvent, and epoxy resin is prepared under an alkaline condition, wherein the epoxy resin has excellent mechanical property, bonding property and chemical stability, but the epoxy resin has larger brittleness and poorer impact resistance, so that the epoxy resin needs to be modified; the fluororubber branched chains are aggregated in a large quantity to form a random special structure, so that the fluororubber has poor low-temperature resistance, but the fluororubber has excellent corrosion resistance, weather resistance and heat resistance, so that the modified epoxy resin adhesive is prepared by adding the fluororubber through ball milling, heating and other modes, and has excellent toughness obtained by toughening through carboxyl-terminated polyether and excellent corrosion resistance increased through the fluororubber.
Further, the active material is either a positive electrode active material or a negative electrode active material.
A preparation method of lithium titanate battery slurry comprises the following steps:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin adhesive, controlling the heating temperature of the lithium titanate and the modified epoxy resin adhesive to be 120 ℃, the pressure to be-0.10 MPa and the heating time to be 20h in the heating process, controlling the heating temperature of the acetylene black and the Ketjen black to be 160 ℃, the pressure to be-0.07 MPa and the heating time to be 25h, taking out the materials after the heating process is finished, and standing the materials for 2h for later use;
step S2, adding the modified epoxy resin adhesive and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the S1, adding active substances and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min, the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 5000-;
And step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
The invention has the beneficial effects that:
(1) according to the invention, lithium titanate battery slurry is prepared by taking lithium titanate, acetylene black, an active substance, a modified epoxy resin adhesive and the like as raw materials, wherein the acetylene black and the Ketjen black are used as conductive agents, both the acetylene black and the Ketjen black exist in a nano form, and have unique branched chain structures and excellent conductive performance;
(2) the modified epoxy resin adhesive is prepared by preparing carboxyl-terminated polyether from polypropylene glycol and phthalic anhydride in the preparation process, has low viscosity and contains flexible molecular chains, can be used for primarily toughening epoxy resin, and is improved in performance by adding fluororubber in a ball milling, heating and other modes;
(3) The viscosity of the high-efficiency lithium titanate battery slurry prepared by the invention is between 2000-2500mpa & s, so that the lithium titanate battery slurry has excellent coating performance, the prepared lithium titanate battery has excellent use effect under high rate, and the modified epoxy resin adhesive is used as a raw material, so that the high-efficiency lithium titanate battery slurry has excellent bonding effect and can endow the lithium titanate battery slurry with good corrosion resistance and excellent stability; the method has simple process, the prepared slurry is uniformly dispersed and does not contain large particles, and the finally prepared lithium titanate battery has good cycle performance.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
A lithium titanate battery slurry is prepared from the following raw materials in parts by weight: 58 parts of lithium titanate, 3 parts of acetylene black, 3 parts of Ketjen black, 10 parts of a positive electrode active substance, 12 parts of a modified epoxy resin adhesive and 75 parts of a 20% dimethyl sulfoxide aqueous solution;
The high-efficiency lithium titanate battery slurry is prepared by the following method:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin glue, wherein the heating temperature of the lithium titanate and the modified epoxy resin glue is controlled to be 120 ℃, the pressure of the lithium titanate and the modified epoxy resin glue is controlled to be-0.10 MPa, the heating time is controlled to be 20h, the heating temperature of the acetylene black and the Ketjen black is controlled to be 160 ℃, the pressure of the acetylene black and the Ketjen black is controlled to be-0.07 MPa, the heating time is controlled to be 25h, and the lithium titanate, the acetylene black, the Ketjen black and the modified epoxy resin glue are taken out and kept stand for 2h after the heating treatment is finished;
step S2, adding the modified epoxy resin adhesive and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S1, adding a positive active substance and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa · S to obtain premixed slurry;
step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to prepare the high-efficiency lithium titanate battery slurry;
The modified epoxy resin adhesive is prepared by the following method:
(1) adding bisphenol A into a dissolving kettle, adding epoxy chloroethane and benzene, stirring at a constant speed, heating to 75 ℃, stirring for 30min, transferring into a reaction kettle, adding 10% sodium hydroxide solution, heating to 45 ℃, stirring at a constant speed for 2h, filtering, standing, pumping the benzene solution into a refluxing benzene kettle, refluxing until no water drop appears in the evaporated benzene, standing and cooling for 45min, transferring into a debenzolization kettle, reducing the pressure at 135 ℃ until no distillate exists, taking out, and drying to obtain epoxy resin;
(2) adding polypropylene glycol into a three-neck flask, heating to 110 ℃, performing vacuum dehydration for 2h, adding phthalic anhydride, heating to 150 ℃, reacting for 5h at the temperature to obtain carboxyl-terminated polyether, taking out, mixing with epoxy resin in a beaker, heating to 85 ℃ until the carboxyl-terminated polyether is molten, adding polyvinylpyrrolidone after uniformly stirring, reacting for 3h, taking out, and standing for 1h to obtain a mixture;
(3) mixing the fluororubber and the mixture, pouring the mixture into a ball mill, carrying out high-speed ball milling at the rotating speed of 1600r/min, adding the mixture into a beaker filled with 100mL of absolute ethyl alcohol after the ball milling is finished, carrying out ultrasonic treatment for 30min, extracting air in the mixed solution, transferring the mixture into a vacuum drying oven, controlling the vacuum degree to be 0.09MPa and the temperature to be 65 ℃, and drying for 12h to obtain the modified epoxy resin adhesive.
Example 2
A lithium titanate battery slurry is prepared from the following raw materials in parts by weight: 60 parts of lithium titanate, 5 parts of acetylene black, 3 parts of Ketjen black, 12 parts of a positive electrode active substance, 13 parts of a modified epoxy resin adhesive and 18 parts of a 20% dimethyl sulfoxide aqueous solution;
the high-efficiency lithium titanate battery slurry is prepared by the following method:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin glue, wherein the heating temperature of the lithium titanate and the modified epoxy resin glue is controlled to be 120 ℃, the pressure of the lithium titanate and the modified epoxy resin glue is controlled to be-0.10 MPa, the heating time is controlled to be 20h, the heating temperature of the acetylene black and the Ketjen black is controlled to be 160 ℃, the pressure of the acetylene black and the Ketjen black is controlled to be-0.07 MPa, the heating time is controlled to be 25h, and the lithium titanate, the acetylene black, the Ketjen black and the modified epoxy resin glue are taken out and kept stand for 2h after the heating treatment is finished;
step S2, adding the modified epoxy resin adhesive and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S1, adding a positive active substance and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa · S to obtain premixed slurry;
And step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
Example 3
A lithium titanate battery slurry is prepared from the following raw materials in parts by weight: 65 parts of lithium titanate, 7 parts of acetylene black, 4 parts of ketjen black, 13 parts of a positive electrode active substance, 14 parts of a modified epoxy resin adhesive and 82 parts of a 20% dimethyl sulfoxide aqueous solution;
the high-efficiency lithium titanate battery slurry is prepared by the following method:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin glue, wherein the heating temperature of the lithium titanate and the modified epoxy resin glue is controlled to be 120 ℃, the pressure of the lithium titanate and the modified epoxy resin glue is controlled to be-0.10 MPa, the heating time is controlled to be 20h, the heating temperature of the acetylene black and the Ketjen black is controlled to be 160 ℃, the pressure of the acetylene black and the Ketjen black is controlled to be-0.07 MPa, the heating time is controlled to be 25h, and the lithium titanate, the acetylene black, the Ketjen black and the modified epoxy resin glue are taken out and kept stand for 2h after the heating treatment is finished;
step S2, adding the modified epoxy resin adhesive and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
S3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S1, adding a positive active substance and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa · S to obtain premixed slurry;
and step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
Example 4
A lithium titanate battery slurry is prepared from the following raw materials in parts by weight: 68 parts of lithium titanate, 8 parts of acetylene black, 5 parts of Ketjen black, 15 parts of a positive electrode active substance, 16 parts of a modified epoxy resin adhesive and 85 parts of a 20% dimethyl sulfoxide aqueous solution;
the high-efficiency lithium titanate battery slurry is prepared by the following method:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin glue, wherein the heating temperature of the lithium titanate and the modified epoxy resin glue is controlled to be 120 ℃, the pressure of the lithium titanate and the modified epoxy resin glue is controlled to be-0.10 MPa, the heating time is controlled to be 20h, the heating temperature of the acetylene black and the Ketjen black is controlled to be 160 ℃, the pressure of the acetylene black and the Ketjen black is controlled to be-0.07 MPa, the heating time is controlled to be 25h, and the lithium titanate, the acetylene black, the Ketjen black and the modified epoxy resin glue are taken out and kept stand for 2h after the heating treatment is finished;
Step S2, adding the modified epoxy resin adhesive and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S1, adding a positive active substance and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa · S to obtain premixed slurry;
and step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
Comparative example 1
Compared with example 1, the preparation method of the comparative example, which replaces the modified epoxy resin adhesive with polyvinylidene fluoride, is as follows:
step S1, respectively heating lithium titanate, acetylene black, Keqin black and polyvinylidene fluoride, wherein the heating temperature of the lithium titanate and the polyvinylidene fluoride is controlled to be 120 ℃, the pressure is-0.10 MPa, the heating time is 20h, the heating temperature of the acetylene black and the Keqin black is controlled to be 160 ℃, the pressure is-0.07 MPa, the heating time is 25h, and the lithium titanate, the acetylene black, the Keqin black and the polyvinylidene fluoride are taken out and kept stand for 2h for later use after the heating treatment is finished;
Step S2, adding polyvinylidene fluoride and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, mixing and grinding acetylene black and Ketjen black, sieving with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the S1, adding a positive active substance and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, the revolution speed of the stirring tank to be 45r/min, the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa & S to obtain premixed slurry;
and step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
Comparative example 2
Compared with the example 1, the preparation method of the comparative example, which uses the graphite fiber to replace the acetylene black and the Ketjen black, is as follows:
step S1, respectively heating lithium titanate, graphite fibers and polyvinylidene fluoride, wherein the heating temperature of lithium titanate and polyvinylidene fluoride is controlled to be 120 ℃, the pressure is-0.10 MPa, the heating time is 20 hours, the heating temperature of graphite fibers is controlled to be 160 ℃, the pressure is-0.07 MPa, the heating time is 25 hours, and the materials are taken out and kept stand for 2 hours after the heating treatment is finished;
Step S2, adding polyvinylidene fluoride and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2h to obtain a mixed solution, and standing for 5h for later use;
s3, grinding graphite fibers, sieving the ground graphite fibers by a 100-mesh sieve, adding the ground graphite fibers into the mixed liquid prepared in the step S1, adding a positive active material and lithium titanate, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 2000-2500MPa & S to obtain premixed slurry;
and step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the high-efficiency lithium titanate battery slurry.
Comparative example 3
This example is a lithium titanate battery slurry in the market.
The dispersion performance, the rate capability and the cycle performance of the high-efficiency lithium titanate battery slurry prepared in the examples 1 to 4 and the comparative examples 1 to 3 are detected, and the results are shown in the following tables 1 to 3;
dispersibility: respectively loading the slurry into a 100mL measuring cylinder, placing the measuring cylinder in a thermostat with the temperature of 25 ℃, and after placing for 24 hours, carrying out solid content test on the slurry at a position 20mm on the surface layer of the measuring cylinder, wherein the test results are shown in the following table 1;
TABLE 1
| Fineness/mum | Viscosity before 24h (mpa. s) | Viscosity (mpa. s) after 24h | Solids content before 24 h/%) | Solids content after 24 h/%) | |
| Example 1 | 32 | 2489 | 2858 | 57.5 | 56.3 |
| Example 2 | 30 | 2407 | 2763 | 56.3 | 56.0 |
| Example 3 | 29 | 2350 | 2740 | 55.8 | 54.9 |
| Example 4 | 27 | 2290 | 2695 | 53.2 | 53.1 |
| Comparative example 1 | 35 | 2673 | 3157 | 60.7 | 59.8 |
| Comparative example 2 | 33 | 2501 | 3368 | 61.5 | 61.0 |
| Comparative example 3 | 57 | 5869 | 6769 | 65.3 | 63.5 |
As can be seen from Table 1, the fineness of examples 1-4 was from 27 to 32 μm, and the fineness of comparative examples 1-3 was from 33 to 57 μm; the viscosity before 24h for examples 1-4 was 2290-2489 (mpa · s), and the viscosity before 24h for comparative examples 1-3 was 2673-5869 (mpa · s); the viscosity after 24h for examples 1-4 was 2695-; the solids content before 24h for examples 1-4 was 53.2-57.5%, and the solids content before 24h for comparative examples 1-3 was 60.7-65.3%; the solids content after 24h was 53.1-56.3% for examples 1-4 and 59.8-63.5% for comparative examples 1-3.
Rate capability:
discharging to 1.5V at constant current at 1C, standing for 10min, and respectively charging to 2.8V at constant current at 3C/5C/8C/10C, with the results shown in Table 2 below;
TABLE 2
| 3C | 5C | 8C | 10C | |
| Example 1 | 98.5% | 97.6% | 95.3% | 94.3% |
| Example 2 | 99.3% | 98.1% | 97.6% | 96.9% |
| Example 3 | 99.7% | 99.2% | 98.5% | 98.0% |
| Example 4 | 100% | 99.5% | 99.1% | 98.3% |
| Comparative example 1 | 96.5% | 94.6% | 93.9% | 93.1% |
| Comparative example 2 | 95.3% | 93.7% | 92.1% | 90.8% |
| Comparative example 3 | 94.7% | 91.5% | 89.7% | 87.5% |
It can be seen from Table 2 that the charge rates of examples 1 to 4 at 3C were 98.5 to 100%, and those of comparative examples 1 to 3 were 94.7 to 96.5%; at 5C, the charging rate of examples 1-4 is 97.6-99.5%, and the charging rate of comparative examples 1-3 is 91.5-94.6%; at 8C, the charging rate of examples 1-4 is 95.3-99.1%, and the charging rate of comparative examples 1-3 is 89.7-93.9%; the charging rate at 10C for examples 1-4 was 94.3-98.3%, and the charging rate for comparative examples 1-3 was 87.5% -93.1%.
Cycle performance:
charging the 3C constant current and constant voltage to 2.8V, stopping the current to 0.3C, standing for 10min, discharging the 3C constant current to 1.5V, standing for 10min, observing the capacity retention rate, and the result is shown in the following table 3;
TABLE 3
| 300 times (twice) | 600 times (one time) | 900 times | 1200 times | |
| Example 1 | 98.7% | 97.6% | 96.8% | 95.3% |
| Example 2 | 99.3% | 98.1% | 97.5% | 96.3% |
| Example 3 | 99.5% | 98.8% | 97.8% | 97.1% |
| Example 4 | 99.7% | 99.1% | 98.5% | 98.2% |
| Comparative example 1 | 94.3% | 93.5% | 92.1% | 91.5% |
| Comparative example 2 | 93.6% | 92.8% | 92.0% | 91.1% |
| Comparison ofExample 3 | 91.2% | 90.2% | 89.5% | 87.3% |
From the above table 3, it can be seen that the capacity retention rates of examples 1-4 are 98.7-99.7% and the capacity retention rates of comparative examples 1-3 are 91.2-94.3% after 300 cycles; the capacity retention rate of the embodiment 1-4 is 97.6-99.1% after 600 times of circulation, and the capacity retention rate of the comparative example 1-3 is 90.2-93.5%; the capacity retention rate of the examples 1 to 4 is 96.8 to 98.5 percent after 900 times of circulation, and the capacity retention rate of the comparative examples 1 to 3 is 89.5 to 92.1 percent; the capacity retention rate of the examples 1 to 4 is 95.3 to 98.2 percent after 1200 times of circulation, and the capacity retention rate of the comparative examples 1 to 3 is 87.3 to 91.5 percent. Therefore, the high-efficiency lithium titanate battery slurry prepared by the invention has lower viscosity, and the lithium titanate battery has good performance under high rate and good cycle performance by combining tables 1-3.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing is illustrative and explanatory only, and it will be appreciated by those skilled in the art that various modifications, additions and substitutions can be made to the embodiments described without departing from the scope of the invention as defined in the appended claims.
Claims (3)
1. A lithium titanate battery slurry is characterized by being prepared from the following raw materials in parts by weight: 58-68 parts of lithium titanate, 3-8 parts of acetylene black, 3-5 parts of ketjen black, 10-15 parts of active substances, 12-16 parts of modified epoxy resin adhesive and 75-85 parts of 20% dimethyl sulfoxide aqueous solution;
the lithium titanate battery slurry is prepared by the following method:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin adhesive, controlling the heating temperature of the lithium titanate and the modified epoxy resin adhesive to be 120 ℃, the pressure to be-0.10 MPa and the heating time to be 20h in the heating process, controlling the heating temperature of the acetylene black and the Ketjen black to be 160 ℃, the pressure to be-0.07 MPa and the heating time to be 25h, taking out the materials after the heating process is finished, and standing the materials for 2h for later use;
step S2, adding the modified epoxy resin adhesive prepared after the treatment of the step S1 and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2 hours to obtain a mixed solution, and standing for 5 hours for later use;
Step S3, mixing and grinding the acetylene black prepared after the treatment in the step S1 and the Ketjen black prepared after the treatment in the step S1, sieving the mixture with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S2, adding an active substance and the lithium titanate prepared after the treatment in the step S1, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 8000mPa S of 5000-;
step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to prepare lithium titanate battery slurry;
the modified epoxy resin adhesive is prepared from the following raw materials in parts by weight: 8-15 parts of polypropylene glycol, 12-20 parts of phthalic anhydride, 18-35 parts of bisphenol A, 24-32 parts of epoxy chloroethane, 18-30 parts of benzene, 5-13 parts of 10% sodium hydroxide solution, 3-5 parts of polyvinylpyrrolidone and 8-15 parts of fluororubber;
the modified epoxy resin adhesive is prepared by the following method:
(1) adding bisphenol A into a dissolving kettle, adding epoxy chloroethane and benzene, stirring at a constant speed, heating to 75 ℃, stirring for 30min, transferring into a reaction kettle, adding 10% sodium hydroxide solution, heating to 45 ℃, stirring at a constant speed for 2h, filtering, standing, pumping the benzene solution into a refluxing benzene kettle, refluxing until no water drop appears in the evaporated benzene, standing and cooling for 45min, transferring into a debenzolization kettle, reducing the pressure at 135 ℃ until no distillate appears, taking out, and drying to obtain epoxy resin;
(2) Adding polypropylene glycol into a three-neck flask, heating to 110 ℃, carrying out vacuum dehydration for 2h, adding phthalic anhydride, heating to 150 ℃, reacting for 5h at the temperature to obtain carboxyl-terminated polyether, taking out, mixing with the epoxy resin in a beaker, heating to 85 ℃ until the carboxyl-terminated polyether is molten, adding polyvinylpyrrolidone after stirring uniformly, reacting for 3h, taking out, and standing for 1h to obtain a mixture;
(3) mixing the fluororubber and the mixture, pouring the mixture into a ball mill, carrying out high-speed ball milling at the rotating speed of 1600r/min, adding the mixture into a beaker filled with 100mL of absolute ethyl alcohol after the ball milling is finished, carrying out ultrasonic treatment for 30min, extracting air in the mixed solution, transferring the mixed solution into a vacuum drying oven, controlling the vacuum degree to be 0.09MPa, controlling the temperature to be 65 ℃, and drying for 12h to obtain the modified epoxy resin adhesive.
2. The lithium titanate battery slurry of claim 1, wherein the active material is either a positive electrode active material or a negative electrode active material.
3. A method of preparing the lithium titanate battery slurry of claim 1, comprising the steps of:
step S1, respectively heating lithium titanate, acetylene black, Ketjen black and modified epoxy resin adhesive, controlling the heating temperature of the lithium titanate and the modified epoxy resin adhesive to be 120 ℃, the pressure to be-0.10 MPa and the heating time to be 20h in the heating process, controlling the heating temperature of the acetylene black and the Ketjen black to be 160 ℃, the pressure to be-0.07 MPa and the heating time to be 25h, taking out the materials after the heating process is finished, and standing the materials for 2h for later use;
Step S2, adding the modified epoxy resin adhesive prepared after the treatment of the step S1 and 20% dimethyl sulfoxide aqueous solution into a stirring tank, controlling the vacuum degree of the stirring tank to be-0.09 MPa, controlling the revolution speed of the stirring tank to be 50r/min and the rotation speed to be 280r/min, stirring for 2 hours to obtain a mixed solution, and standing for 5 hours for later use;
step S3, mixing and grinding the acetylene black prepared after the treatment in the step S1 and the Ketjen black prepared after the treatment in the step S1, sieving the mixture with a 100-mesh sieve, adding the mixture into the mixed solution prepared in the step S2, adding an active substance and the lithium titanate prepared after the treatment in the step S1, controlling the vacuum degree of a stirring tank to be-0.08 MPa, controlling the revolution speed of the stirring tank to be 45r/min and the rotation speed to be 300r/min, and stirring until the viscosity of the mixed slurry is 8000mPa S of 5000-;
and step S4, transferring the premixed slurry into a mixer for stirring, controlling the vacuum degree to be-0.08 MPa, controlling the revolution speed of a stirring tank to be 20r/min and the rotation speed to be 500r/min, stirring for 30min, taking out, and sieving by a 200-mesh sieve to obtain the lithium titanate battery slurry.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101699642A (en) * | 2009-10-27 | 2010-04-28 | 无锡市明杨电池有限公司 | Method for manufacturing positive pole piece of lithium iron phosphate battery |
| CN101937990A (en) * | 2010-09-27 | 2011-01-05 | 彩虹集团公司 | Preparation method of nano lithium iron phosphate positive slurry |
| CN103311527A (en) * | 2013-05-22 | 2013-09-18 | 南京双登科技发展研究院有限公司 | Preparation method of cathode slurry of lithium titanate battery |
| CN103682295A (en) * | 2012-09-26 | 2014-03-26 | 华为技术有限公司 | Lithium ion battery negative electrode material and preparation method thereof as well as lithium ion battery negative electrode plate and lithium ion battery |
| AU2015100977A4 (en) * | 2014-12-12 | 2015-09-17 | Ningbo Csr New Energy Technology Co., Ltd | Method for preparing hybrid capacitor cathode slurry |
| CN106207129A (en) * | 2016-08-31 | 2016-12-07 | 中航锂电（洛阳）有限公司 | A kind of preparation method of anode slurry of high-rate |
| CN106299331A (en) * | 2015-05-29 | 2017-01-04 | 普天新能源（深圳）有限公司 | Based lithium-ion battery positive plate comprising lithium titanate coating and preparation method thereof and lithium ion battery |
| CN107834048A (en) * | 2017-11-24 | 2018-03-23 | 深圳市比克动力电池有限公司 | Negative electrode of lithium titanate battery slurry and preparation method thereof |
| CN107834019A (en) * | 2017-11-02 | 2018-03-23 | 沈阳国科金能新材料有限公司 | A kind of cell size preparation method of high solids content |
| CN108054339A (en) * | 2017-11-28 | 2018-05-18 | 山西长征动力科技有限公司 | A kind of preparation method of efficient lithium titanate battery slurry |
-
2019
- 2019-04-02 CN CN201910261987.5A patent/CN109950505B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101699642A (en) * | 2009-10-27 | 2010-04-28 | 无锡市明杨电池有限公司 | Method for manufacturing positive pole piece of lithium iron phosphate battery |
| CN101937990A (en) * | 2010-09-27 | 2011-01-05 | 彩虹集团公司 | Preparation method of nano lithium iron phosphate positive slurry |
| CN103682295A (en) * | 2012-09-26 | 2014-03-26 | 华为技术有限公司 | Lithium ion battery negative electrode material and preparation method thereof as well as lithium ion battery negative electrode plate and lithium ion battery |
| CN103311527A (en) * | 2013-05-22 | 2013-09-18 | 南京双登科技发展研究院有限公司 | Preparation method of cathode slurry of lithium titanate battery |
| AU2015100977A4 (en) * | 2014-12-12 | 2015-09-17 | Ningbo Csr New Energy Technology Co., Ltd | Method for preparing hybrid capacitor cathode slurry |
| CN106299331A (en) * | 2015-05-29 | 2017-01-04 | 普天新能源（深圳）有限公司 | Based lithium-ion battery positive plate comprising lithium titanate coating and preparation method thereof and lithium ion battery |
| CN106207129A (en) * | 2016-08-31 | 2016-12-07 | 中航锂电（洛阳）有限公司 | A kind of preparation method of anode slurry of high-rate |
| CN107834019A (en) * | 2017-11-02 | 2018-03-23 | 沈阳国科金能新材料有限公司 | A kind of cell size preparation method of high solids content |
| CN107834048A (en) * | 2017-11-24 | 2018-03-23 | 深圳市比克动力电池有限公司 | Negative electrode of lithium titanate battery slurry and preparation method thereof |
| CN108054339A (en) * | 2017-11-28 | 2018-05-18 | 山西长征动力科技有限公司 | A kind of preparation method of efficient lithium titanate battery slurry |
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