11643results about "Positive electrodes" patented technology

The present invention provides a cathode for use in a secondary electrochemical cell, such cathode being coated with a very thin, protective film, permeable to ions. The protective film of the cathode usually has a thickness of up to about 0.1 mum and it provides protection against high voltage charging and overdiscbarging. The present invention further provides a secondary electrochemical cell comprising such a cathode.

A lithium/iron disulfide electrochemical battery cell with a high discharge capacity. The cell has a lithium negative electrode, an iron disulfide positive electrode and a nonaqueous electrolyte. The iron disulfide of the positive electrode has a controlled average particle size range which allows the electrochemical cells to exhibit desired properties in both low and high rate applications. In various embodiments, the iron disulfide particles are wet milled, preferably utilizing a media mill or milled utilizing a non-mechanical mill such as a jet mill, which reduces the iron disulfide particles to a desired average particle size range for incorporation into the positive electrode.

A lithium transition metal-based compound powder for a lithium secondary battery positive electrode material that can achieve both improvements of load characteristics such as rate and output characteristics and a higher density is a lithium transition metal-based compound powder containing, as a main component, a lithium transition metal-based compound that has a function of allowing elimination and insertion of lithium ions, and including a crystal structure belonging to a layer structure, wherein primary particles are aggregated to form secondary particles, the ratio A/B of a median diameter A of the secondary particles to an average diameter (average primary particle diameter B) is in the range of 8 to 100, and 0.01≦FWHM(110)≦0.5 where FWHM(110) is the half width of a (110) diffraction peak present near a diffraction angle 2θ of 64.5° in a powder X-ray diffraction analysis using a CuKα line.

A system includes a thin-film battery and an activity-activated switch. The system is placed on a substrate with an adhesive backing. In some embodiments, the substrate is flexible. Also formed on the substrate is an electrical circuit that includes electronics. The activity-activated switch places the thin-film battery in electrical communication with the circuit and electronics. The battery and the circuit are formed on the substrate and may be comprised of one or a plurality of deposited layers.

Disclosed herein is a cathode active material coated with a fluorine compound for lithium secondary batteries. The cathode active material is structurally stable, and improves the charge-discharge characteristics, cycle characteristics, high-voltage characteristics, high-rate characteristics and thermal stability of batteries.

A nonaqueous electrolyte battery includes a positive electrode containing an active material, a negative electrode, and a nonaqueous electrolyte, the negative electrode including a current collector and a negative electrode active material supported by the current collector, the negative electrode active material having a Li insertion potential not lower than 0.2V (vs. Li/Li⁺) and an average primary particle diameter not larger than 1 μm, and a specific surface area of the negative electrode, excluding a weight of the current collector, as determined by the BET method falls within a range of 3 to 50 m²/g.

The present disclosure relates to a positive electrode active material precursor for a lithium secondary battery, a positive electrode active material manufactured by using thereof, and a lithium secondary battery comprising the same. More specifically, it relates to a positive electrode active material precursor for a lithium secondary battery as a secondary particle comprising transition metals, and formed by gathering of a plurality of primary particles having different a-axis direction length to c-axis direction length ratio, wherein the a-axis direction length to c-axis direction length ratio of the primary particle making up the secondary particle is increased from the center to the surface of the secondary particle; a positive electrode active material; and a lithium secondary battery comprising the same.

The present invention provides high capacity and high voltage Li-ion batteries that have a carbonaceous cathode and a nonaqueous electrolyte solution comprising LiF salt and an anion receptor that binds the fluoride ion. The batteries can comprise dual intercalating electrode Li ion batteries. Methods of the present invention use a cathode and electrode pair, wherein each of the electrodes reversibly intercalate ions provided by a LiF salt to make a high voltage and high specific capacity dual intercalating electrode Li-ion battery. The present methods and systems provide high-capacity batteries particularly useful in powering devices where minimizing battery mass is important.

An energy storage device comprising at least one negative electrode, wherein each negative electrode is individually selected from (i) an electrode comprising negative battery electrode material; (ii) an electrode comprising capacitor electrode material; (iii) a mixed electrode comprising either—a mixture of battery and capacitor electrode material or—a region of battery electrode material and a region of capacitor electrode material, or—a combination thereof, and wherein the energy storage device either comprises at least one electrode of type (iii), or comprises at least one electrode of each of types (i) and (ii),—at least one positive electrode, wherein the positive electrode comprises positive battery electrode material and a charging ability-increasing additive, such as one or a mixture of: (a) carbon nanomaterial, vapour grown carbon fibre, fullerene, or a mixture thereof, and (b) tin dioxide conductive materials.

A lithium-ion battery includes a cathode that includes an active cathode material. The active cathode material includes a cathode mixture that includes a lithium cobaltate and a manganate spinel a manganate spinel represented by an empirical formula of Li_(1+x1)(Mn_1−y1A′_y2)_2−x2O_z1. The lithium cobaltate and the manganate spinel are in a weight ratio of lithium cobaltate: manganate spinel between about 0.95:0.05 to about 0.55:0.45. A lithium-ion battery pack employs a cathode that includes an active cathode material as described above. A method of forming a lithium-ion battery includes the steps of forming an active cathode material as described above; forming a cathode electrode with the active cathode material; and forming an anode electrode in electrical contact with the cathode via an electrolyte.

A rechargeable alkali metal battery comprising: (a) an anode comprising an alkali metal layer and a dendrite penetration-resistant layer comprising an amorphous carbon or polymeric carbon matrix, an optional carbon or graphite reinforcement phase dispersed in this matrix, and a lithium- or sodium-containing species that are chemically bonded to the matrix and/or the optional carbon or graphite reinforcement to form an integral layer that prevents dendrite penetration, wherein the lithium- or sodium-containing species is selected from Li₂CO₃, Li₂O, Li₂C₂O₄, LiOH, LiX, ROCO₂Li, HCOLi, ROLi, (ROCO₂Li)₂, (CH₂OCO₂Li)₂, Li₂S, Li_xSO_y, Na₂CO₃, Na₂O, Na₂C₂O₄, NaOH, NaiX, ROCO₂Na, HCONa, RONa, (ROCO₂Na)₂, (CH₂OCO₂Na)₂, Na₂S, Na_xSO_y, or a combination thereof, wherein X═F, Cl, I, or Br, R=a hydrocarbon group, x=0-1, y=1-4; (b) a cathode; and (c) a separator and electrolyte component; wherein the dendrite penetration-resistant layer is disposed between the alkali metal layer and the separator.

The present invention provides a high-capacity and low-cost non-aqueous electrolyte secondary battery, comprising: a negative electrode containing, as a negative electrode active material, a ssubstance capable of absorbing/desorbing lithium ions and/or metal lithium; a separator; a positive electrode; and an electrolyte, wherein the positive electrode active material contained in the positive electrode is composed of crystalline particles of an oxide containing two kinds of transition metal elements, the crystalline particles having a layered crystal structure, and oxygen atoms constituting the oxide forming a cubic closest packing structure.

A redox chemical shuttle comprising an aromatic compound substituted with at least one tertiary carbon organic group and at least one alkoxy group (for example, 2,5-di-tert-butyl-1,4-dimethoxybenzene) provides repeated overcharge protection in rechargeable lithium-ion cells.

A nonaqueous electrolyte battery includes a case, a positive electrode housed in the case and including a positive electrode active material containing a lithium-nickel composite oxide and at least one of lithium hydroxide and lithium oxide, the sum of lithium hydroxide and lithium oxide falling within not less than 0.1% to not more than 0.5% by weight based on the total amount of the positive electrode active material, a negative electrode housed in the case and capable of lithium intercalation-deintercalation, and a separator sandwiched between the positive electrode and the negative electrode and impregnated with a nonaqueous electrolyte containing γ-butyrolactone.

A primary alkaline battery includes a cathode having a cathode active material and carbon fibers, an anode, a separator and an alkaline electrolyte. The carbon fibers have diameters less than about 250 nanometers.

Sodium ion batteries are based on sodium based active materials selected among compounds of the general formula:

A_aM_b(XY₄)_cZ_d,

wherein A comprises sodium, M comprises one or more metals, comprising at least one metal which is capable of undergoing oxidation to a higher valence state, Z is OH or halogen, and XY₄ represents phosphate or a similar group. The anode of the battery includes a carbon material that is capable of inserting sodium ions. The carbon anode cycles reversibly at a specific capacity greater than 100 mAh/g.

In one embodiment, an active cathode material comprises a mixture that includes: at least one of a lithium cobaltate and a lithium nickelate; and at least one of a manganate spinel represented by an empirical formula of Li_(1+x1)(Mn_1−y1A′_y1)_2−x1O_z1 and an olivine compound represented by an empirical formula of Li_(1−x2)A″_x2MPO₄. In another embodiment, an active cathode material comprises a mixture that includes: a lithium nickelate selected from the group consisting of LiCoO₂-coated LiNi_0.8Co_0.15Al_0.05O₂, and Li(Ni_1/3Co_1/3Mn_1/3)O₂; and a manganate spinel represented by an empirical formula of Li_(1+x7)Mn_2−y7O_z7. A lithium-ion battery and a battery pack each independently employ a cathode that includes an active cathode material as described above. A method of forming a lithium-ion battery includes the steps of forming an active cathode material as described above; forming a cathode electrode with the active cathode material; and forming an anode electrode in electrical contact with the cathode via an electrolyte. A system comprises a portable electronic device and a battery pack or lithium-ion battery as described above.

A positive active material of a lithium-sulfur battery includes a sulfur-conductive agent-agglomerated complex in which a conductive agent particle is attached onto a surface of a sulfur particle having an average particle size less than or equal to 7 μm. The sulfur-conductive agent-agglomerated complex is manufactured by mixing a sulfur powder and a conductive agent powder to form a mixture, and milling the mixture.

Positive electrode active materials comprising a dopant in an amount of 0.1 to 10 mole percent of Mg, Ca, Sr, Ba, Zn, Cd or a combination thereof are described that have high specific discharge capacity upon cycling at room temperature and at a moderate discharge rate. Some materials of interest have the formula Li_1+xNi_αMn_β-δCo_γA_δX_μO_2−zF_z, where x ranges from about 0.01 to about 0.3, δ ranges from about 0.001 to about 0.15, and the sum x+α+β+γ+δ+μ can approximately equal 1.0. The materials can be coated with a metal fluoride to improve the performance of the materials especially upon cycling. The materials generally can have a tap density of at least 1.8 g/mL. Also, the materials can have an average discharge voltage of around 3.6 V.

Composite cathode active materials having a large diameter active material and a small diameter active material are provided. The ratio of the average particle diameter of the large diameter active material to the average particle diameter of the small diameter active material ranges from about 6:1 to about 100:1. Mixing the large and small diameter active materials in a proper weight ratio improves packing density Additionally, including highly stable materials and highly conductive materials in the composite cathode active materials improves volume density, discharge capacity and high rate discharge capacity.

Disclosed is a cathode electrode having a cathode active material layer stacked on a current collector. The cathode active material layer includes a porous conductive material having a surface coated with sulfur and/or a sulfur-containing organic compound and/or pores filled with sulfur and/or a sulfur-containing organic compound. A lithium secondary battery employing the cathode electrode also is disclosed. The cathode electrode is structurally stable during charging and discharging since the structure of the cathode active material layer can be maintained even at the phase transition of sulfur during charging and discharging.

This invention discloses materials for positive electrodes of secondary batteries and their methods of fabrication. Said materials comprise of granules of an active material for positive electrodes coated with an oxide layer. The active material is one or more of the following: oxides of lithium cobalt, oxides of lithium nickel cobalt, oxides of lithium nickel cobalt manganese, oxides of lithium manganese, LiCoO₂, LiNi_1-xCo_xO₂, LiNi_1/3Co_1/3Mn_1/3O₂, and LiMn₂O₄. The non-oxygen component in the oxide layer is one or more of the following: aluminum, magnesium, zinc, calcium, barium, strontium, lanthanum, cerium, vanadium, titanium, tin, silicon, boron, Al, Mg, Zn, Ca, Ba, Sr, La, Ce, V, Ti, Sn, Si, and B. Said non-oxygen component of the granules is between 0.01 wt. % to 10 wt. % of said granules of active material. The methods of fabrication for said materials includes the steps of mixing an additive and an active material for positive electrodes uniformly in water or solvent, evaporating said solvent or water, and heat treating the remaining mixture at 300° C. to 900° C. for between 1 hour to 20 hours. The additive is a compound of one or more of the following elements: aluminum, magnesium, zinc, calcium, barium, strontium, lanthanum, cerium, vanadium, titanium, tin, silicon, boron, Al, Mg, Zn, Ca, Ba, Sr, La, Ce, V, Ti, Sn, Si, and B where the element is between 0.01 wt. % to 10 wt. % of said active material. Using the materials of positive electrodes disclosed above or materials for positive electrodes fabricated in the methods disclosed above in batteries produces batteries with excellent cycling and high temperature properties.