11results about How to "Improve volume expansion" patented technology

The invention discloses a pre-lithiated silicon-carbon negative electrode material as well as a preparation method and application thereof. The pre-lithiated silicon-carbon negative electrode material comprises composite particles and a surface coating layer coating the outer surfaces of the composite particles, the mass of the composite particles accounts for 85%-99% of the total mass of the pre-lithiated silicon-carbon negative electrode material; the composite particles are compounds of pre-lithiated porous carbon and nano silicon particles; the composite particles are obtained by uniformly depositing nano silicon particles in pores of pre-lithiated porous carbon; the mass of the pre-lithiated porous carbon accounts for 15-95% of the total mass of the composite particles; the pre-lithiated porous carbon comprises lithium metal particles and porous carbon, and the lithium metal particles are attached to the surfaces of pores of the porous carbon; the mass of the lithium metal particles accounts for 0.1-10% of the total mass of the pre-lithiated silicon-carbon negative electrode material; when the pre-lithiated silicon-carbon negative electrode material is applied to the lithium battery, the first-circle coulombic efficiency of the lithium battery can be improved.

According to the negative electrode and the battery, an active material in the negative electrode is a composite negative electrode material and comprises a phosphorus-carbon composite material and a carbon material, and the mass percent of the phosphorus-carbon composite material is greater than or equal to 50%. By mixing the phosphorus-carbon composite material with carbon materials such as graphite for use, the cycle performance of a phosphorus-carbon system battery can be greatly improved, and the problem of volume expansion can be solved, so that the lithium ion battery can effectively give consideration to high energy and high power performance, and precipitation of lithium dendrites on the surface of a negative electrode can be effectively avoided to a certain extent; and the safety performance of the battery is greatly improved. Furthermore, the addition of the carbon material is beneficial to improving the processing performance of the phosphorus-carbon negative electrode plate.

The invention discloses a tin-carbon negative electrode material as well as a preparation method and application thereof. The tin-carbon negative electrode material comprises an inner core and a shell, the inner core is a tin-carbon composite material; the shell is a carbon coating layer coating the outer surface of the porous carbon; wherein the tin-carbon composite material comprises porous carbon and tin deposited in pores of the porous carbon; the mass of the porous carbon accounts for 15-95% of the total mass of the tin-carbon composite material; the mass of the tin-carbon composite material accounts for 85-99% of the total mass of the tin-carbon negative electrode material; the mass of tin accounts for 0.1%-85% of the total mass of the tin-carbon negative electrode material, preferably 3%-30%; the tin-carbon composite material is obtained by depositing tin obtained by decomposing distannane in pores of porous carbon through a vapor deposition method; the tin-carbon negative electrode material provided by the invention is used as a negative electrode active material to prepare a negative electrode plate and assemble the negative electrode plate into a secondary battery, so that the first-circle coulombic efficiency of the secondary battery can be effectively improved.

An active material in the negative electrode is a composite negative electrode material and comprises a composite phosphorus carbon material and soft carbon. By mixing the phosphorus-carbon composite material with soft carbon, the cycle performance of a phosphorus-carbon system battery can be greatly improved, and the problem of volume expansion can be solved, so that the lithium ion battery can effectively give consideration to high energy and high power performance, precipitation of lithium dendrites on the surface of a negative electrode can be effectively avoided to a certain extent, and the safety performance of the battery is greatly improved. Furthermore, the addition of the soft carbon is beneficial to improving the processing performance of the phosphorus-carbon negative electrode plate.

An active material in the negative electrode is a composite negative electrode material and comprises a composite phosphorus carbon material and hard carbon. By mixing the phosphorus-carbon composite material with hard carbon, the cycle performance of a phosphorus-carbon system battery can be greatly improved, and the problem of volume expansion can be solved, so that the lithium ion battery can effectively give consideration to high energy and high power performance, precipitation of lithium dendrites on the surface of a negative electrode can be effectively avoided to a certain extent, and the safety performance of the battery is greatly improved. Furthermore, the addition of the hard carbon is beneficial to improving the processing performance of the phosphorus-carbon negative electrode plate.

The preparation method comprises the following steps: firstly, taking 20 to 30 weight percent of 85 alumina clinker, 15 to 25 weight percent of forsterite, 11 to 24 weight percent of fused magnesite, 4 to 6 weight percent of pyrophyllite, 6 to 8 weight percent of 95 silicon carbide, 5 to 7 weight percent of 90 silicon carbide, 22 to 27 weight percent of ferro-silicon nitride, 9 to 13 weight percent of coke powder, 6 to 8 weight percent of metal Si powder, 5 to 7 weight percent of aluminum oxide micro powder, 7 to 8 weight percent of bentonite and 14 to 20 weight percent of white mud as raw materials; and adding 2-4wt% of high-temperature asphalt, 1-2wt% of carbon black and 15-18wt% of stemming oil, and mixing in a mixer for 20-30 minutes to obtain the additive for the anhydrous stemming. The invention has the advantages of environmental protection, no pollution, effective improvement of strength and stability, and improvement of oxidation resistance and erosion resistance.

This invention relates to the field of secondary battery technology, specifically to a silicon-carbon composite material, its preparation method, and a lithium-ion battery. The preparation method of the silicon-carbon composite material includes: reacting an organometallic framework ZIF-8 in a saturated metal salt solution and then evaporating and crystallizing it to obtain a metal salt-coated organometallic framework Salt@ZIF-8; pulverizing a silicon-copper alloy precursor and the Salt@ZIF-8 at a mass ratio of 1:0.05-0.7 to obtain a mixed powder; and subjecting the mixed powder to a pyrolysis reaction and acid leaching treatment to obtain the silicon-carbon composite material. The silicon-carbon composite material obtained by this invention exhibits excellent structural stability and electrochemical performance, effectively mitigating the volume expansion of the silicon anode and improving cycle performance and rate performance.

The present disclosure relates to an anode material, a method for preparing the same, and a lithium ion battery, which belong to the technical field of energy storage materials. The anode material includes a LixMySiO4 material, a carbon material and nano-silicon. The LixMySiO4 material and the carbon material has a network structure, independently forming a first skeleton and a second skeleton in the anode material respectively. The first skeleton and the second skeleton are entangled with each other, and the nano-silicon is distributed in the matrix or / and on the surface of LixMySiO4 material. In the LixMySiO4 material, the values of x and y satisfy charge balance, and M includes a metal element capable of reducing silicon oxides, the metal element excludes Li. The anode material has better electrical conductivity, more stable structure, lower volume expansion, higher electrical conductivity, higher first efficiency and excellent rate performance.

The present application relates to a negative electrode material and a battery, wherein the negative electrode material comprises a core and a coating layer located on at least part of the surface of the core, wherein the core comprises a silicon material and a filler, wherein the filler is distributed in the silicon material, wherein the filler comprises a carbon material and metal nanoparticles, and wherein the coating layer comprises a first layer and a second layer arranged in sequence, wherein the first layer is distributed on at least part of the surface of the core, wherein the first layer comprises a carbon layer and metal nanowires distributed on the carbon layer; and the second layer is distributed on at least part of the surface of the first layer. The negative electrode material provided by the present application can effectively inhibit the volume expansion of silicon, while improving the electron transmission efficiency and ion transmission efficiency of the negative electrode material, and improving the cycle retention rate of the negative electrode material.

The invention discloses a high-entropy sulfide negative electrode material, a lithium ion battery and preparation and application of the high-entropy sulfide negative electrode material and the lithium ion battery. The high-entropy sulfide is FeNiCoCuLiSx, x is 5.5-6.5, and the preparation method of the high-entropy sulfide comprises the following steps: adding nitrates of Fe, Ni, Co, Cu and Li into an organic solvent and a template agent glycerol according to a molar ratio of 1: 1: 1: 1: 1: 1, mixing and dissolving, reacting the obtained mixed solution at 150-170 DEG C, dispersing and centrifuging to obtain a precursor; and dispersing the precursor and thioacetamide in an organic solvent, reacting at 140-160 DEG C, and dispersing and centrifuging after the reaction to obtain the product high-entropy sulfide. The obtained high-entropy sulfide has excellent long cycle stability, high specific capacity and high-rate charge-discharge performance.

The embodiment of the invention provides a composite coating electrode, a preparation method thereof and a battery, and the composite coating electrode comprises a negative electrode current collector; the first coating is attached to the surface of the negative electrode current collector, the first coating comprises a first active substance, and the first active substance is a phosphorus-carbon composite material; the second coating is attached to the surface of the first coating, the second coating comprises a second active substance, and the expansion coefficient of the second active substance is smaller than that of the first active substance. In the working process of the battery, the second coating which is located on the first coating and has a relatively small expansion coefficient can hoop the first coating so as to inhibit the expansion of the phosphorus-carbon coating, so that the negative electrode active material is prevented from being stripped from the current collector in the long-cycle process; according to the composite coating electrode provided by the embodiment of the invention, the volume expansion problem of a phosphorus-carbon system battery can be improved, and the cycle life of the battery is prolonged.