37results about How to "High discharge capacity retention" patented technology

The invention relates to the use of a nitrogen silylated compound as additive in a nonaqueous electrolytic solution. The electrolytic solution is suitable for use in electrochemical cells such as lithium and lithium ion batteries. Batteries using this electrolytic solution have long cycle life and high capacity retention.

An anode and a secondary battery capable of improving the charge and discharge efficiency are provided. The anode includes an anode current collector, and an anode active material layer provided on the anode current collector. The anode active material layer has a plurality of anode active material particles containing at least one of a simple substance of silicon, a compound of silicon, a simple substance of tin and a compound of tin, and has a coat containing an oxo acid salt in at least part of the surface of the anode active material particles.

A non-aqueous electrolytic solution composed of two or more organic compounds dissolved in a solvent composed of a cyclic carbonate and a chain carbonate, in an amount of 0.01 to 8 weight % for each compound, in which both of the two organic compounds have a reduction potential higher than those of the cyclic and chain carbonates, and in which one of the organic compounds has a reduction potential equal to that of another organic compound or has a reduction potential lower or higher than that of another organic compound by a potential of less than 0.4 V is favorably employable for a non-aqueous secondary battery.

The invention relates to the use of an amine oxide as an additive in a nonaqueous electrolytic solution. The electrolytic solution is suitable for use in electrochemical cells such as lithium batteries and lithium ion batteries. Batteries using this electrolyte solution have long life and high capacity retention.

The invention discloses a high-multiplying power lithium ion battery and a preparation method thereof. The lithium ion battery comprises a cathode plate, an anode plate, a composite diaphragm and an electrolyte solution, and the surfaces of the diaphragm are coated with composite conductive layers; each composite conductive layer is composed of a bonding agent, a conductive agent and micropores; the cathode plate and the anode plate are each of a full-tab structure. The preparation method comprises the steps that the diaphragm coated with the composite conductive layers, the cathode plate and the anode plate are subjected to a winding process to prepare a wound core, and the wound core is subjected to the processes of packaging, baking, liquid injecting, hot-cold pressing, forming and capacity grading to prepare the high-multiplying power lithium ion battery. According to the high-multiplying power lithium ion battery and the preparation method thereof, by improving the characteristics of the interfaces between the diaphragm and cathode and anode membranes and optimizing the structural design of the battery, the bonding performance of the contact interfaces between the diaphragm and the cathode and anode plates is improved, the lithium ion transfer resistance between the different interfaces is decreased, the electronic conductivity of the cathode and anode plates is enhanced, the porosity and the air permeability of the composite diaphragm are improved, wetting of the electrolyte solution to the diaphragm is improved, the retaining capacity of the electrolyte solution in the battery is improved, the high-multiplying power performance of the lithium ion battery is greatly improved, the high-multiplying power discharge capacity retention rate is increased by 10% or above compared with the prior art, and the high-multiplying power lithium ion battery is suitable for industrialized production.

Provided are a nonaqueous electrolytic solution having an electrolyte salt dissolved in a nonaqueous solvent, the electrolyte salt including at least one first lithium salt selected from LiPF₆, LiBF₄, LiN(SO₂F)₂, LiN(SO₂CF₃)₂, and LiN(SO₂C₂F₅)₂, and at least one second lithium salt selected from a lithium salt having an oxalate structure, a lithium salt having a phosphate structure, and a lithium salt having an S═O group, with a sum total of the first lithium salt and the second lithium salt being four or more, and an energy storage device using the same.

This nonaqueous electrolytic solution is not only able to improve electrochemical characteristics at a high temperature and much more improve a discharge capacity retention rate and low-temperature output characteristics after a high-temperature storage test but also able to improve low-temperature input characteristics even for high-density electrodes.

A method of increasing the discharge capacity retention of a non-aqueous lithium ion secondary battery having a positive electrode active material, a combination of a lithium element and a complex metal oxide, a negative electrode, and a non-aqueous electrolytic solution comprising an electrolyte dissolved in a non-aqueous solvent which is a combination of a cyclic carbonate and a linear carbonate by incorporating a disulfide derivative having the formula:

R¹—S—S—R²

wherein each of R¹ and R² independently represents a phenyl group, a benzyl group, a tolyl group, a pyridyl group, a pyrimidyl group, an alkyl group having 1 to 12 carbon atom, or a cycloalkyl group having 3 to 6 carbon atoms, in which each group has no substituent groups or has one or more alkyl groups into the non-aqueous electrolytic solution.

The invention provides an electrolyte, a preparation method thereof and a lithium ion battery. The electrolyte comprises a solvent, a lithium salt and an additive, wherein the solvent is composed of acyclic carbonate solvent and a chain carbonate solvent, the mass ratio of the cyclic carbonate solvent in the electrolyte is 1.5-20%, and the mass ratio of the chain carbonate solvent in the electrolyte is 47-86.1%; the lithium salt is lithium hexafluorophosphate, and lithium bis(fluorosulfonyl)imide and/or bistrifluoromethanesulfonimide lithium; and the additive is selected from one or more of ethylene sulfite, lithium oxalyldifluoro borate, lithium difluoro(bisoxalate)phosphate, vinylene carbonate and thiophene. The electrolyte can enable the lithium ion battery to have excellent dischargecapacity retention ratio and high-temperature cycling stability.

The invention provides a positive pole piece and a preparation method thereof, a lithium ion battery containing the positive pole piece and application of the lithium ion battery. The positive pole piece comprises a current collector, a first active substance layer and a second active substance layer which are sequentially stacked, and lithium cobalt oxide particles in the second active substancelayer comprise lithium cobalt oxide particles with first particle sizes and lithium cobalt oxide particles with second particle sizes, wherein the D50 of the lithium cobalt oxide particles with the first particle size is 5-8 [mu]m; and the D50 of the lithium cobalt oxide particles with the second particle size is 12 [mu]m-16 [mu]m. By adopting the structure, the high-temperature storage performance and the power performance after high-temperature storage of the battery are greatly improved while the power performance of the battery is not lost, and the power performance and the high-temperature storage performance of the unmanned aerial vehicle battery are well considered.

Disclosed is a sodium rechargeable battery having better cycle characteristics than the conventional sodium rechargeable battery. The sodium rechargeable battery comprises a positive electrode comprising a composite metal oxide, a negative electrode comprising a carbon material, which can occlude and desorb Na ions, and an electrolyte. The composite metal oxide comprises Na and M1, wherein M1 represents two or more elements selected from the group consisting of Mn, Fe, Co, and Ni, and has a Na : M1 molar ratio of a : 1 wherein a is a value in a range of more than 0.5 and less than 1. The sodium rechargeable battery may further comprise a separator. The separator comprises a laminated porous film comprising a heat-resistant resin-containing heat-resistant porous layer and a thermoplastic resin-containing porous film stacked on the heat-resistant resin-containing heat-resistant porous layer.

The invention discloses an anode material of a lithium battery. The anode material of the lithium battery contains lithium cobalt oxide, wherein the grain diameter D50 of the lithium cobalt oxide is 2-16 microns; the specific surface area of the lithium cobalt oxide is 0.2m<2>/g-1.0m<2>/g. According to the anode material of the lithium battery, an inventor does a lot of researches on the grain diameter and the specific surface area of the lithium cobalt oxide; when the grain diameter and the specific surface area of the lithium cobalt oxide are finally found to be in the range, a path of embedding lithium ions is short, the resistance is small and the resistance of the battery is low and low-temperature discharging requirements of the lithium battery are met. Furthermore, the invention further discloses a lithium battery containing the anode material; the lithium battery adopts the anode material containing the lithium cobalt oxide with the small grain diameter so that the ion resistance is small and the lithium ions are easy to embed; therefore, the discharge capacity retention ratio of the lithium battery at the low temperature is improved effectively.

The invention relates to a formation process of a high-nickel ternary system lithium battery and belongs to the field of battery formation processes. The formation process comprises the following steps of (a) carrying out side sealing and top sealing on a lithium battery shell by using a platinum-doped aluminum-plastic composite film, reserving more than 60-120% of platinum-doped aluminum-plasticcomposite film at one side of the shell and reserving a liquid injection opening in the lithium battery shell; (b) injecting an electrolyte containing sodium fluoride through the liquid injection opening in a carbon dioxide atmosphere, introducing a mixed gas of carbon dioxide, a fluorine gas and sulfur dioxide and then sealing the liquid injection opening; and (c) reaching high temperature from low temperature, carrying out charging and discharging for three times, carrying out vacuum-pumping sealing after formation is ended, extracting the gas generated during formation and cutting away thereserved more than 60-120% of platinum-doped aluminum-plastic composite film. According to the formation process, the content of lithium fluoride, lithium sulfite and the like in an SEI film is increased through introducing diluted fluorine gas and sulfur dioxide in the formation process, so that the SEI film is more stable and denser.

The invention provides a lithium ion battery diaphragm, a preparation method thereof,k and a lithium ion battery. The lithium ion battery diaphragm comprises a porous polyolefin base membrane; a composite coating layer which wraps the surface of the porous polyolefin base membrane, wherein the compound coating layer comprises phenolic resin and silicon dioxide. According to the lithium ion batterydiaphragm provided by the invention, the phenolic resin and the silicon dioxide in the compound coating layer have a synergistic effect, so that the obtained lithium ion battery diaphragm has relatively good affinity with an electrolyte, and therefore, the lithium ion battery diaphragm has relatively good electrolyte absorptivity and relatively good electrolyte wettability. The lithium ion battery diaphragm disclosed by the invention is prepared into the lithium ion battery, so the lithium ion battery diaphragm and the electrolyte have relatively good compatibility, and the discharge capacityretention rate and coulombic efficiency of the obtained lithium ion battery are relatively high. In addition, the electrochemical stability window of the diaphragm is improved through the compound coating layer, and the diaphragm is hopeful to be applied to the field of high-voltage lithium batteries.

The invention provides lithium ion battery cathode slurry, a preparation method thereof, and a lithium ion battery. The preparation method comprises the following steps: (1) mixing positive electrodeactive powder with conductive agent powder, and degassing to obtain first powder; (2) mixing the first powder with a wetting aid gas to obtain second powder; (3) mixing the second powder with a solvent, and degassing to obtain intermediate slurry; and (4) mixing the intermediate slurry with a binder to obtain the lithium ion battery positive electrode slurry. According to the preparation method provided by the invention, the wettability of the powder in the preparation process of the positive electrode slurry is improved, the wetting time is shortened, the production capacity is improved, andthe time cost is saved; and the lithium ion battery is high in energy density and excellent in electrochemical performance.

The invention discloses an electrolytic solution additive for improving high and low temperature performance of a lithium battery, a preparation method of the electrolytic solution additive, an electrolytic solution containing the electrolytic solution additive and an electrochemical device. The electrolytic solution additive is shown in the following structural formula defined in the specification, and can relatively improve the discharge capacity retention ratio of a lithium battery containing the electrolytic solution additive at high temperature and low temperature and the cycle capacity retention ratio at high temperature and low temperature.

The invention provides a lithium ion battery electrolyte and a preparation method and application thereof. The electrolyte comprises an organic solvent, a lithium salt and an additive, wherein the additive comprises vinylene carbonate and lithium difluoro (oxalato) borate. According to the wide-temperature 12V lithium ion battery electrolyte, the electrochemical performance of the battery is improved by regulating and controlling the types and the addition amount of the additives, and the wide-temperature 12V lithium ion battery electrolyte simultaneously meets high and low temperature discharge characteristics and is long in cycle life.

The present invention relates to an electrolytic copper foil current collector where the surface properties are controlled to achieve a high adhesiveness to a negative electrode material. An electrolytic copper foil has a first surface and the second surface, the electrolytic copper foil comprising a first protective layer on the first surface side, a second protective layer on the second surface side, and a copper film between the first and second protective layers, wherein the coupling coefficient at the first surface or second surface of the electrolytic copper foil is 1.5 to 9.4 as represented by coupling coefficient=Rp/μm+peak density/30+amount of Cr adhesion/(mg/m²) (here, peak density is measured according to ASME standard B46.1). The electrolytic copper foil has a high adhesiveness to a negative electrode material and a low electrical resistance can be provided by controlling the surface properties of the electrolytic copper foil surface.