55results about How to "Avoid Lithium" patented technology

The invention discloses a lithium-ion battery rapid charging method capable of preventing lithium separation. The lithium-ion battery rapid charging method comprises the following steps: obtaining a lithium separation boundary when a lithium-ion battery is charged; according to the lithium separation boundary, setting a charging current rule of the lithium-ion battery; in the charging current rule, controlling charging current so that lithium separation of the lithium-ion battery does not occur; and charging the lithium-ion battery according to the charging current rule. The lithium-ion battery rapid charging method capable of preventing the lithium separation has the advantages that the charging current rule of the lithium-ion battery is set according to the lithium separation boundary when the lithium-ion battery is charged, safe and rapid charging is realized and the cycle life of the battery is not influenced.

The invention discloses high voltage electrolyte considering high and low temperature performance and a lithium ion battery using the electrolyte. The high voltage electrolyte comprises a non-aqueous organic solvent, an electrolyte lithium salt, an ether nitrile compound and a low impedance additive, wherein the non-aqueous organic solvent comprises a carbonate solvent and a linear carboxylic acid ester solvent with a wide liquid range; the electrolyte lithium salt is a combination of lithium hexafluorophate and lithium triflurosulfimide according to a molar ratio of 0.01-0.5; and the low impedance additive is a cyclic sulfate compound. The linear carboxylic acid ester solvent for perfecting the electrode/ electrolyte interface is contained in the high voltage electrolyte, by means of the optimized combination of the ether nitrile compound, the lithium triflurosulfimide and the cyclic sulfate compound and other additives, a high voltage battery can be guaranteed to have excellent circulation performance, and meanwhile, the excellent high and low temperature performance of the high voltage battery of storage for 18 h in a full charge state at 85 DEG C and no lithium separation in the full charge state at 0 DEG C is considered.

The invention provides a composite lithium-ion battery cell with low internal resistance, and a preparation technology of the composite lithium-ion battery cell, aiming at overcoming the defects. The battery cell internally comprises at least two single winding cells which are respectively provided with a positive pole lug and a negative pole lug; the pole lugs with the same polarity of the single winding cells are welded to form a whole body in a way of ultrasonic welding, so that the composite battery cell can be formed; the pole lugs of a positive pole piece and a negative pole piece of each single winding cell are arranged in the middle. After the composite lithium-ion battery cell is adopted, the internal resistance of a battery is effectively reduced under the condition that the battery capacity is not changed, so that the multiplying performance of the battery is improved, and the safety of the battery is improved.

The invention provides a lithium supplementing negative pole piece, which comprises a porous current collector, lithium supplementing coatings respectively positioned on the upper surface and the lower surface of the porous current collector, and an active substance layer positioned on the surfaces of the lithium supplementing coatings, wherein the through holes of the porous current collector arefurther filled with the lithium supplementing coatings, and the lithium supplementing coating comprises the following components in percentage by mass: 90-98% of metal lithium powder, 1-5% of a mixture of an electronic good conductor and a lithium ion good conductor and 1-5% of a binder. According to the invention, uniform and accurate lithium supplement of the silicon-carbon negative electrode can be realized, the first charge-discharge efficiency and the energy density of the battery are improved, and the conductivity of the silicon-carbon negative electrode piece is improved.

The invention provides a lithium-supplementing current collector, a preparation method and application thereof, a negative pole piece and a lithium ion battery. The lithium-supplementing current collector comprises a current collector body and a lithium-supplementing material layer. The current collector body comprises a first carbon-coated layer, a substrate layer and a second carbon-coated layerwhich are arranged in sequence, wherein two adjacent layers of the first carbon-coated layer, the substrate layer and the second carbon-coated layer are tightly attached and fixedly connected; a plurality of through holes are formed in the first carbon-coated layer at intervals and penetrate through the substrate layer and the second carbon-coated layer; and the plurality of through holes are filled with the lithium supplementing material layer. According to the lithium-supplementing current collector disclosed by the invention, the current collector contains a lithium supplementing substance, so that accurate lithium supplementing of a silicon-carbon negative electrode can be realized, the internal resistance of the pole piece after lithium supplementing is reduced, and the rate capability and the cycle performance of a battery are improved.

The invention provides a packaging method for reducing poor insulation of a soft package lithium battery. The packaging method comprises the following step of: S1, carrying out pit punching on an aluminum-plastic film to form a battery cell pit and an air bag pit; S2, coating the inner side of the aluminum-plastic film heat sealing region with a heat-resistant coating, and subjecting the heat-resistant coating to cross-linking curing treatment; S3, putting the welded battery cell into a battery cell pit, and carrying out top sealing and side sealing on the edge of the outer side of the heat-resistant coating to form a top sealing stamp and a side sealing stamp; S4, baking the battery cell, and performing primary sealing after liquid injection to form a primary seal; S5, performing batterycell formation, and performing air exhaust secondary sealing after aging to form a secondary seal; and S6, trimming and folding the battery cell. The inner side edge of the heat sealing region is coated with the heat-resistant coating, so that adhesion of an aluminum-plastic film PP layer in the heat affected region can be effectively prevented during heat sealing of the battery cell, the PP layeris prevented from being damaged during subsequent production and use of the soft package battery cell, and the proportion of poor insulation is reduced.

The invention discloses a lithium ion battery negative plate as well as a preparation method application thereof and a lithium ion battery, and belongs to the technical field of secondary lithium batteries. The negative plate is prepared in a method comprising the following steps of: in an inert atmosphere, uniformly distributing a solution containing a lithium compound onto the surface of the negative plate by adopting an electrostatic spinning technology, and drying. Lithium is supplemented on the surface of the negative plate in a wet method by adopting the electrostatic spinning technology, so that the lithium-containing compound is uniformly distributed on the surface of the negative plate to form a fibrous lithium strip with a relatively large specific surface area and a porous structure; compared with the existing lithium supplementing method in a spraying or dropwise adding manner, the lithium can be uniformly supplemented, a beneficial effect of precisely and controllably supplementing the lithium can be achieved, and lithium precipitation or deformation of the negative plate is effectively avoided.

A charging method for a lithium ion battery comprises the following steps that constant current charging is carried out on the battery with the current Ia to the capacity of 2-10%, and then standing is carried out for time ta; constant current charging is continuously carried out on the battery with the current Ib to the capacity of 40-70%, and then standing is carried out for time tb; constant current charging is continuously carried out on the battery with the current Ic to the capacity of 80-95%, and then standing is carried out for time tc; the battery is charged with the constant voltage to the battery capacity of 100%, wherein Ib is larger than Ia and Ic. By means of the charging method, temperature rising of a battery core in the large-rate charging process is effectively reduced, bleeding of lithium in the charging process is effectively prevented, the circulation reversibility of the battery core is improved, and the circulation performance is improved.

The embodiment of the invention discloses a vehicle-mounted power battery. The vehicle-mounted power battery comprises a shell, a charging power receiving coil and a battery cell module. The shell comprises a groove arranged on the outer surface of the shell and a containing cavity arranged in the shell, the charging power receiving coil is contained in the groove and used for receiving energy from a power supply device and outputting the energy, and the battery cell module is contained in the containing cavity and is electrically connected with the charging power receiving coil and used for receiving and storing the energy output by the charging power receiving coil. The vehicle-mounted power battery is simple in structure, low in production line assembling difficulty and beneficial to improving the production efficiency. The embodiment of the invention further discloses a chargeable and dischargable energy storage system and an electric automobile.

The invention discloses a multifunctional composite negative plate and a preparation method thereof, and a secondary battery. The multifunctional composite negative plate comprises a negative currentcollector layer and a negative active material layer. The negative electrode active material layer comprises a plurality of negative electrode active material assemblies. The negative electrode activematerial assemblies are prepared from a negative electrode material, a binder and a conductive additive, the plurality of negative electrode active material assemblies are distributed between the negative electrode current collector layer and the diaphragm in a two-dimensional laminated structure or a three-dimensional laminated structure, and the plurality of negative electrode active material assemblies have different physical properties or different chemical compositions. According to the invention, structural design is performed on the negative electrode active material layer, the multifunctional composite negative plate and the secondary battery give full play to the functions of different negative active material assemblies, the defects of single negative active material layer structure and short function in the prior art are overcome, and give consideration to the comprehensive excellent performances such as safety, rate capability, high and low temperature characteristics, service life, cycle life and the like.

The invention relates to a secondary battery including a positive electrode pole piece, a negative electrode pole piece, an isolating membrane and an electrolyte. The positive electrode pole piece includes a positive active material layer containing a ternary positive electrode material. The negative electrode pole piece includes a negative active material layer, and active materials contain a carbon material A and a carbon material B. The carbon material B has a high reversible capacity and cooperates with the ternary positive electrode material to achieve a high gram capacity of the battery.Compared with the carbon material B, the carbon material A has a low degree of graphitization, a relatively large interlayer spacing and higher mechanical strength. The combination of the two carbonmaterials ensures that the negative electrode pole piece has both high reversible capacity and good pressure resistance, and the cycle life of the battery is improved.

The invention belongs to the technical field of lithium ion battery preparation, and particularly relates to an electrolyte infiltration method of a lithium ion battery. The electrolyte infiltration method of the lithium ion battery pole piece provided by the invention comprises the following steps of high-pressure liquid injection, primary shelving, primary pre-charging, secondary shelving, secondary pre-charging, tertiary shelving and liquid supplementation, and the step of secondary pre-charging is limited. The method is suitable for all lithium ion batteries, especially for square lithium batteries, and overcomes the problem that the infiltration effect of thick and large square batteries is difficult to improve. By adopting the method provided by the invention, the infiltration effect of the battery can be obviously improved, the electrolyte absorption amount is obviously increased, and the internal resistance of the battery is obviously reduced.

The invention belongs to the technical field of battery production and manufacturing, and specifically relates to a winding battery cell. The winding battery cell comprises a positive plate (1), a negative plate (2) and an isolating membrane (3) arranged between the positive plate (1) and the negative plate (2). The positive plate (1), the isolating membrane (3) and the negative plate (2) are wound to form a winding core (4) of a hollow structure, and the radian alpha of the corner of the winding core (4) is smaller than 180 degrees and smaller than 0 degree. According to the invention, the problem of powder falling and even lithium precipitation at the corner due to overlarge stress at the corner of the pole piece in the battery cell can be improved, and the service life of the battery isprolonged. In addition, the invention also discloses a battery and a battery module structure.

The invention relates to the technical field of lithium batteries, and discloses a pole piece with uniform thickness of a tab ceramic coating and a preparation method thereof, aiming at the problems of easy short circuit and lithium precipitation in a tab area in the prior art, the pole piece (1) comprises a foil material (2), the foil material comprises a tab (2.1) and a middle area (2.2), and two sides of the middle area are coated with active substance coatings (3). The connection area of the middle area (2.2) and the tab (2.1) is coated with a ceramic coating (4), and the surface formed bythe ceramic coating (4) and the active substance coatings (3) is parallel to the foil (2). Through adoption of the tab ceramic coating method, the problem of internal short circuit of the battery canbe effectively solved, meanwhile, the tab is coated with the ceramic layer, it can be guaranteed that the thickness of the tab of the pole piece is consistent with that of the middle area, lithium precipitation of the battery can be effectively avoided, the safety of the battery is improved, the preparation process is simple, and the high-quality rate of finished products is high.

The invention discloses a lithium ion battery and a charging method thereof. The charging method of the lithium ion battery is a charging voltage limiting method or a charging capacity limiting method, wherein the N/P ratio of the lithium ion battery is less than 1.02, and the N/P ratio is the ratio of the capacity of the negative pole piece per unit area to the capacity of the positive pole piece per unit area. According to the charging method of the lithium ion battery, the safety of the battery cell can be guaranteed, lithium separation in the charging process can be effectively prevented, the lithium ion battery is low in cost and high in energy density, and the cycle life is remarkably prolonged.

The invention relates to the technical field of batteries, and provides a battery cell hot-pressing tool. The battery cell hot-pressing tool comprises a first hot-pressing piece with a first hot-pressing groove; a second hot-pressing piece which is provided with a second hot-pressing groove and is used for being matched with the first hot-pressing piece, wherein the height of the second hot-pressing piece relative to the first hot-pressing piece is adjustable; a hot-pressing inner core which is used for fixing a battery cell, is mounted on the first hot-pressing piece and is at least partially located in the first hot-pressing groove, or is mounted on the second hot-pressing piece and is at least partially located in the second hot-pressing groove. According to the embodiment of the invention, structural deformation of the battery cell in the cyclic charging and discharging process is avoided, so that lithium precipitation of the battery cell in the cyclic charging process is prevented, the energy density of the battery cell is improved, the cycle life of the battery cell is prolonged, and the structure is simpler.

The invention provides a lithium-supplementing positive electrode slurry and a preparation method and application thereof, the preparation method comprises the following steps: (1) mixing a solvent and a binder, adding a conductive agent, carrying out primary vacuum stirring, mixing with a lithium-supplementing agent, and carrying out secondary vacuum stirring to obtain a conductive adhesive solution; and (2) mixing the conductive adhesive solution with the positive electrode active material in three times, and adding the solvent to adjust the viscosity to obtain the lithium-supplementing positive electrode slurry. The lithium-supplementing agent is added into the conductive adhesive, so that the lithium-supplementing agent is preferentially mixed with a small amount of components such as the binder and the conductive agent to form the uniform conductive adhesive solution, then the adhesive solution is added into the positive electrode material, the positive electrode main material is infiltrated by the adhesive solution. The wetting angle of the glue solution to the positive electrode main material is less than 90 degrees, so that the processing steps are not increased, and the lithium supplement agent can be effectively dispersed.

The invention discloses a winding type battery cell and a battery, and belongs to the technical field of batteries. The winding type battery cell comprises a positive plate and a negative plate, the positive plate comprises a first section and a second section, and the negative plate comprises a third section; the first section and the third section are respectively wound along a first direction to form a winding structure; the outermost ring of the first section is located on the inner side of the outermost ring of the third section, and the second section is wound in the second direction from the tail end of the first section so as to wrap the outermost ring of the third section; wherein the two sides of the third section are coated with symmetrically distributed negative electrode active material layers, and the surfaces of the first section and the second section are coated with positive electrode active material layers opposite to the negative electrode active material layers respectively. According to the scheme provided by the embodiment of the invention, the problem of lithium precipitation caused by the existence of a single-sided paste region in the existing negative plate can be relieved.

The invention discloses a preparation method of an anti-overcharged lithium ion battery pole piece and belongs to the technical field of preparation of battery pole pieces. The preparation method disclosed by the invention has the benefits that firstly, sodium dodecyl sulfate is mixed with deionized water to obtain a self-made dispersing liquid, so that the internal resistance of a lithium ion battery is increased, and the side reaction between a negative electrode and an electrolyte is reduced; in addition, particles have high thermal stability; polyethylene, 2-bromoanisole and N-methyl pyrrolidone are subjected to mixed reaction continuously to obtain self-made thermal expansion latex, wherein the polyethylene is a thermal expansion polymer, and once the battery is overcharged or over-discharged, the thermal expansion polymer can quickly expand; in addition, the 2-bromoanisole contains an ortho-bromo group, and the ortho-bromo group increases the stability of a benzene ring Pi bond conjugate system to a certain extent; adsorption products can hinder ion migration, charge transfer and the like, so that the overall impedance property of the battery is increased, and the anti-overcharge and cycle performances of the lithium ion battery pole piece are further improved; therefore, the application prospect is wide.

The invention discloses a new-source automobile power battery top-speed flexible charging control method and system and an automobile. The control method comprises the steps: employing a bidirectionalcharging system for generating a sine alternating current with the set frequency to conduct alternating current charging and discharging on a battery, performing rapid and efficient preheating on thebattery from inside to outside by means of ohm heat production of the battery, and stopping preheating after the set temperature is reached; and then charging the battery by adopting constant current, and after the voltage of the battery reaches a cut-off voltage, carrying out constant-voltage charging on the battery by the cut-off voltage. The charging speed of the new energy automobile is increased, battery lithium precipitation is avoided, the influence on the service life of the lithium ion battery is small, additional battery preheating equipment is not needed, implementation is easy, and the application prospect is very wide.