A secondary battery in which the difference between the voltage at the time of discharging and the voltage at the time of charging is small, ensuring good energy efficiency, and the charge/discharge life is long. Therefore, in order to attain the above-described object, a secondary battery containing a positive electrode, a negative electrode, and an electrolytic solution, wherein at least one of the positive electrode and the negative electrode contains, as the active material, at least one selected from the group consisting of a metal ion-containing fluoride, a metal oxide, a metal sulfide, a metal nitride, and a metal phosphide; the electrolytic solution contains an anion receptor; and the anion receptor forms a salt or a complex with an anion contained in the active material, thereby enabling the active material to dissolve in the electrolytic solution.

To provide a method for forming a storage battery electrode including an active material layer with high density in which the proportion of conductive additive is low and the proportion of the active material is high. To provide a storage battery having a higher capacity per unit volume of an electrode with the use of a storage battery electrode formed by the formation method. A method for forming a storage battery electrode includes the steps of forming a mixture including an active material, graphene oxide, and a binder; providing a mixture over a current collector; and immersing the mixture provided over the current collector in a polar solvent containing a reducer, so that the graphene oxide is reduced.

A lithium ion secondary battery in which the positive electrode active material is predominantly composed of olivine type lithium phosphorus oxide, the positive electrode contains a binder predominantly composed of a resin containing polyamic acid and polyimide, and a carbon material is contained in the positive electrode as a conductive agent. A ratio A/B of a peak intensity A of an aromatic ring to a peak intensity B of an imide ring of the positive electrode by FTIR is 0.20 or more.

A composite particle is provided. The particle comprises a first particle component and a second particle component in which: (a) the first particle component comprises a body portion and a surface portion, the surface portion comprising one or more structural features and one or more voids, whereby the surface portion and body portion define together a structured particle; and (b) the second component comprises a removable filler; characterized in that (i) one or both of the body portion and the surface portion comprise an active material; and (ii) the filler is contained within one or more voids comprised within the surface portion of the first component. The use of the particle in applications such as electrochemical cells, metal-ion batteries such as secondary battery applications, lithium air batteries, flow cell batteries, fuel cells, solar cells, filters, sensors, electrical and thermal capacitors, micro-fluidic devices, gas or vapor sensors, thermal or dielectric insulating devices, devices for controlling or modifying the transmission, absorption or reflectance of light or other forms of electromagnetic radiation, chromatography or wound dressings is disclosed.

A cathode material for a lithium-ion secondary battery which is made of agglomerated secondary particles formed by agglomeration of a plurality of primary particles of electrode active material particles made of a transition metal lithium phosphate compound having an olivine structure that is coated with a carbonaceous material, in which an arithmetic average roughness Ra of agglomerated secondary particle surfaces observed using a three-dimensional scanning electron microscope is 15 nm or more and 25 nm or less.

Provided herein are methods of forming solid-state ionically conductive composite materials that include particles of an inorganic phase in a matrix of an organic phase. The methods involve forming the composite materials from a precursor that is polymerized in-situ after being mixed with the particles. The polymerization occurs under applied pressure that causes particle-to-particle contact. In some embodiments, once polymerized, the applied pressure may be removed with the particles immobilized by the polymer matrix. In some implementations, the organic phase includes a cross-linked polymer network. Also provided are solid-state ionically conductive composite materials and batteries and other devices that incorporate them. In some embodiments, solid-state electrolytes including the ionically conductive solid-state composites are provided. In some embodiments, electrodes including the ionically conductive solid-state composites are provided.

A cathode material for a lithium-ion secondary battery of the present invention is active material particles including central particles represented by General Formula Li.sub.xA.sub.yD.sub.zPO.sub.4 (0.9<x<1.1, 0<y1, 0z<1, and 0.9<y+z<1.1; here, A represents at least one element selected from the group consisting of Co, Mn, Ni, Fe, Cu, and Cr, and D represents at least one element selected from the group consisting of Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, and Y) and a carbonaceous film that coats surfaces of the central particles, in which a coarse particle ratio in a particle size distribution is 35% or more and 65% or less.

The present invention provides a method for preparing an anode active material for a nonaqueous lithium secondary battery, comprising the steps of: preparing a carbon-based material; forming a precursor coating layer comprising Me and A (wherein A is O or S) on the surface of the carbon-based material; supplying a P precursor to the precursor coating layer of the carbon-based material; and converting at least a part of the precursor coating layer into a compound represented by Me.sub.x1P.sub.y1 (wherein x1>0 and y1>0) by the reaction of the precursor coating layer and the P precursor, thereby forming a phosphide coating layer, wherein Me is at least one type of the same metal element selected from among Mo, Ni, Fe, Co, Ti, V, Cr, Nb and Mn.

Provided herein are methods of forming solid-state ionically conductive composite materials that include particles of an inorganic phase in a matrix of an organic phase. The methods involve forming the composite materials from a precursor that is polymerized in-situ after being mixed with the particles. The polymerization occurs under applied pressure that causes particle-to-particle contact. In some embodiments, once polymerized, the applied pressure may be removed with the particles immobilized by the polymer matrix. In some implementations, the organic phase includes a cross-linked polymer network. Also provided are solid-state ionically conductive composite materials and batteries and other devices that incorporate them. In some embodiments, solid-state electrolytes including the ionically conductive solid-state composites are provided. In some embodiments, electrodes including the ionically conductive solid-state composites are provided.

Provided herein are methods of forming solid-state ionically conductive composite materials that include particles of an inorganic phase in a matrix of an organic phase. The methods involve forming the composite materials from a precursor that is polymerized in-situ after being mixed with the particles. The polymerization occurs under applied pressure that causes particle-to-particle contact. In some embodiments, once polymerized, the applied pressure may be removed with the particles immobilized by the polymer matrix. In some implementations, the organic phase includes a cross-linked polymer network. Also provided are solid-state ionically conductive composite materials and batteries and other devices that incorporate them. In some embodiments, solid-state electrolytes including the ionically conductive solid-state composites are provided. In some embodiments, electrodes including the ionically conductive solid-state composites are provided.