Abstract: An electrode active material for non-aqueous secondary batteries containing a compound represented by formula (1) is a material that is less likely to dissolve in an electrolyte during charge and discharge, and that exhibits an excellent discharge capacity and excellent charge-and-discharge cycle characteristics: the compound represented by formula (1) wherein Y1 and Y2 are identical or different and represent an oxygen atom, a sulfur atom, or a selenium atom, R1 to R8 are identical or different and represent an oxygen atom or a group represented by —OLi, R9 to R12 are identical or different and represent a hydrogen atom or an organic group, and bonds that are each represented by a solid line and a dashed line indicate a single bond or a double bond.

Abstract: A positive electrode for electrochemical device includes a positive current collector and a positive electrode material layer supported on the positive current collector. The positive electrode material layer includes a positive electrode active material. The positive electrode active material includes an inner core portion containing polyaniline and a surface layer portion containing poly(3,4-ethylenedioxythiophene) and polythiophene. The inner core portion is fibrous or grain-aggregate, and the surface layer portion covers at least a part of the inner core portion. Furthermore, an electrochemical device includes the above-described positive electrode, a negative electrode including a negative electrode material layer that occludes and releases a lithium ion, and a nonaqueous electrolytic solution having lithium ion conductivity.

Abstract: An electrode including conduction channels includes at least one electrode layer layered onto a current collector, the electrode layer including a plurality of active material particles and a plurality of high aspect ratio components. The high aspect ratio components are configured to provide ion conduction channels through the electrode layer. In some examples, the electrode may include two or more electrode layers, at least one of which includes high aspect ratio components. In some examples, the high aspect ratio components may be oriented transverse to the current collector to provide ion transport through a first electrode layer to a second electrode layer.

Abstract: At least one of the anode and cathode of a lithium-ion processing electrochemical cell are prepared with a layer of mixed particles of both active lithium battery electrode materials and lithium ion adsorbing capacitor materials, or with co-extensive, contiguous layers of battery electrode particles in one layer and capacitor particles in the adjoining layer. The proportions of active battery electrode particles and active capacitor particles in one or both of the electrodes are predetermined to provide specified energy density (Wh/kg) and power density (W/kg) properties of the cell for its intended application.

Abstract: According to one embodiment, an electrode is provided. The electrode includes an active material-containing layer including active material particles and solid electrolyte particles being present away from the active material particles. The active material particles have lithium ion conductivity. The solid electrolyte particles have first ion conductivity. The solid electrolyte particles include a first ion that is at least one selected from the group consisting of an alkali metal ion excluding a lithium ion, a Ca ion, an Mg ion, and an Al ion.

Abstract: A method of making an electrode for an electrochemical cell includes the step of providing an electrode composite comprising from 70-98% active material, from 0-10% conductive material additives, and from 2-20% polymer binder, based on the total weight of the electrode composite. The electrode composite is mixed and then compressed the electrode composite into an electrode composite sheet. The electrode composite sheet is applied to a current collector with pressure to form an electrode, wherein the electrode possesses positive characteristics for adhesion according to ASTM standard test D3359-09e2, entitled Standard Test Methods for Measuring Adhesion by Tape Test, and wherein the electrode composite sheet and the electrode possess positive characteristics for flexibility according to the Mandrel Test. The binder can be a single nonfluoropolymer binder. Dry process electrodes are also disclosed.

Abstract: The present disclosure provides a cable-type secondary battery which includes: at least one inner electrode; a separation layer formed to surround the outer surface of the inner electrode and configured to prevent a short of the electrodes; a sheet-type outer electrode surrounding the separation layer or the inner electrode and formed by spiral winding; and a polymer electrolyte coating layer formed to surround the sheet-type outer electrode, wherein the sheet-type outer electrode is formed by spiral winding to avoid an overlap.

Abstract: A heat dissipation structure for a flexible display is disclosed, and includes: a substrate, an anode metal layer, light emitting diode elements, a pixel defining layer, a cathode metal layer, and a heat conducting insulator disposed in sequence. The pixel defining layer has grooves, and the heat conducting insulator is sandwiched between the anode metal layer and the cathode metal layer, and disposed in the grooves. The heat conducting insulator is used to connect the anode metal layer and the cathode metal layer, so as to form an electrically insulating and thermally conducting path between the anode metal layer and the cathode metal layer.

Abstract: One aspect of the present invention provides a sulfide solid-state battery provided with: a negative electrode collector containing copper; a negative electrode mix layer disposed on the negative electrode collector, and containing a negative electrode active material; a positive electrode mix layer containing a positive electrode active material; a sulfide solid electrolyte layer sandwiched between the negative electrode mix layer and the positive electrode mix layer, and having a protruding portion that protrudes from a peripheral edge of the negative electrode mix layer and extends up to the negative electrode collector; and a reference electrode disposed in the protruding portion.

Abstract: A secondary battery electrode manufacturing method comprises applying a slurry for a first layer to a current collector, applying a slurry for a second layer to the slurry for the first layer before the slurry for the first layer dries, and drying the slurries to obtain a laminated structure in which the first and second layers are laminated in this order on the current collector. A first and second binder or thickener for the respective slurries are selected such that when viscosities are measured for a first solution including solvent and the first binder or thickener dissolved in the solvent in a specific mass ratio and a second solution including a solvent and the second binder or thickener dissolved in the solvent at the same mass ratio under the same conditions, the viscosity of the first solution is higher than the viscosity of the second solution.

Abstract: An electrode body, which includes a positive electrode plate and a negative electrode plate, includes a positive-electrode tab group that is composed of a plurality of positive electrode tabs. The positive-electrode tab group is disposed between a sealing plate and an electrode body, and a positive-electrode current collector includes a base portion and a tab connection portion that is folded from an end of the base portion. The base portion of the positive-electrode current collector is connected to a positive electrode terminal, and the tab connection portion of the positive-electrode current collector is connected to the positive-electrode tab group. A fuse portion is formed in the positive-electrode current collector, and a first-insulator second region of a first insulator, which is connected to an inner insulator, is disposed between the base portion and the tab connection portion.

Abstract: To provide a non-aqueous electrolyte secondary battery negative electrode material that can be produced even without performing a heat treatment at a high temperature such as 2,000° C. or higher and can have the discharge capacity further increased. The non-aqueous electrolyte secondary battery negative electrode material according to the invention has a core portion including carbonaceous negative electrode active material particles; and a shell portion including a polyimide and silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles. There is a feature that the value of the ratio of the volume average particle size (D50) of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to the volume average particle size (D50) of the carbonaceous negative electrode active material particles is 0.001 to 0.

Abstract: An electrolyte composition has a fluoroalkylsulfonyl salt and water. The water is present, relative to the fluoroalkylsulfonyl salt, at a molar ratio within a range of 0.1:1 to 10:1, inclusive. This creates a “water-in-salt” in which individual water molecules are surrounded by salt rather than vice versa. Water contained in this environment is electrochemically stabilized relative to a bulk water. The electrolyte also has an organic carbonate present, relative to the fluoroalkylsulfonyl salt, at a molar ratio within a range of 0.1:1 to 50:1, inclusive. It has been discovered that inclusion of the organic carbonate further increases the electrochemical stability of the water within the “in-salt” environment.

Abstract: A non-aqueous electrolyte secondary battery includes a negative electrode, a positive electrode, and an electrolyte solution. The electrolyte solution contains at least one selected from the group consisting of ethylene carbonate, fluoroethylene carbonate, and vinylene carbonate. The negative electrode includes a negative electrode mixture layer. The negative electrode mixture layer contains a silicon-containing particle and a graphite particle. In a Log-differential pore volume distribution of the negative electrode mixture layer, the ratio of a Log-differential pore volume at a pore diameter of 2 ?m to a Log-differential pore volume at a pore diameter of 0.2 ?m is within a range of 10.5 to 33.1.

Abstract: A vapour deposition method for preparing an amorphous lithium-containing oxide or oxynitride compound not containing phosphorous comprises providing a vapour source of each component element of the compound, including at least a source of lithium, a source of oxygen, a source of nitrogen in the case of an oxynitride compound, and a source or sources of one or more glass-forming elements; heating a substrate to substantially 180° C. or above; and co-depositing the component elements from the vapour sources onto the heated substrate wherein the component elements react on the substrate to form the amorphous compound.

Abstract: A composite including: at least one selected from a silicon oxide of the formula SiO2 and a silicon oxide of the formula SiOx wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

Abstract: Provided is a solid electrolyte including electrolyte particles, wherein each of the electrolyte particles includes at least one of an O—S—O structure and an O—S—OH structure.

Abstract: A method of manufacturing a membrane electrode assembly for hydrogen fuel cells includes mixing an electrode binder with a catalyst, followed by dispersing and thermal treatment, to prepare an electrode slurry, coating release paper with the electrode slurry to produce an electrode, and bonding the release paper-coated electrode to an electrolyte membrane, followed by thermal treatment, to perform electrode-membrane bonding.

Abstract: An all-solid-state battery including a laminated body with a cathode current collecting layer, cathode active material layer, solid electrolyte layer, anode active material layer, and anode current collecting layer in this order, and a restraining member that applies a restraining pressure to the laminated body in a laminated direction; containing a conductive material, an insulating inorganic substance, and a polymer, is in at least one of a position between the cathode active material layer and the cathode current collecting layer, and a position between the anode active material layer and the anode current collecting layer; the content of the insulating inorganic substance in the PTC layer is 10 volume % or more and 40 volume % or less; and a proportion of a particle size D90 of the insulating inorganic substance, D90, to a thickness of the PTC layer, TPTC, regarded as D90/TPTC is 0.6 or more and 1.0 or less.

Abstract: In an aspect, an electrode for an electrochemical cell comprises: a structure having a nano- or micro-architected three-dimensional geometry; said structure comprising one or more active carbon allotrope materials; wherein said structure is characterized by an average density less than or equal to 2.3 g cm?3 and an average specific strength (strength-to-density ratio) greater than or equal to 0.004 GPa g?1 cm3. Also disclosed herein are methods for making an electrode for an electrochemical cell, and methods for making an electrochemical cell.

Abstract: The application provides a porous film and a lithium-ion battery. The porous film according to the present application has excellent adhesion, and the pore structure of the porous film can still be well maintained after being immersed in the electrolyte, thereby reducing the probability of pore blockage of the porous film and allowing the lithium-ion battery to have high ionic conductivity. Therefore, the rate performance of the lithium-ion battery is greatly improved, and the lithium-ion battery provided has excellent rate performance and cycle performance.

Abstract: An energy harvesting device includes: a first nanoporous electrode and a second nanoporous electrode, each of which is configured to which store electrical charge; a first current collector connected to the first nanoporous electrode and a second current collector connected to the second nanoporous electrode; and an enclosure that contains the first and second nanoporous electrodes and the first and second current collectors and transfers a force applied from the outside to the first nanoporous electrode and the second nanoporous electrode, wherein at least one of the first nanoporous electrode and the second nanoporous electrode comprises an ion conductive polymer.

Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode including a positive electrode mix layer, a negative electrode including a negative electrode mix layer, and a nonaqueous electrolyte containing a nonaqueous solvent. A surface of the negative electrode mix layer is provided with grooves. The nonaqueous electrolyte contains 10 volume percent or more of a fluorinated solvent with respect to the volume of the nonaqueous solvent and has a viscosity (25° C.) of 3.50 mPa·s or more as measured with a differential pressure viscometer.

Abstract: The present disclosure relates to a process for separation of enantiomers of the amino acid from a racemic mixture. The process comprises electrolyzing the first electrolyte having 1 molar solution of lithium perchlorate and 0.01 molar solution of racemic mixture of amino acid in an electrochemical cell containing a working electrode having polycrystalline metal surface configured to adsorb L-enantiomer of amino acid using a saw-tooth current. Further, the polarity of the saw-tooth current is reversed to de-adsorb the L-enantiomer of amino acid from the working electrode into the second electrolyte re-filled in the cell. The process of the present disclosure to separate enantiomer of amino acid from a racemic mixture is simple and economical.

Abstract: A positive electrode active material of the present invention is used for a positive electrode for a lithium-ion secondary battery and includes a positive electrode active material particle A expressed by General Formula (A): Li?NixCoyMn(1?x?y)O2 (where 0<??1.15, 0.7?x?0.9, 0<y?0.2, and 0<(1?x?y)); and one kind or two or more kinds of positive electrode active material particles B selected from a positive electrode active material particle B1 expressed by General Formula (B1): Li?NiaCobAl(1?a?b)O2 (where 0<??1.15, 0.7?a?0.9, 0<b?0.2, and 0<(1?a?b)), a positive electrode active material particle B2 expressed by General Formula (B2): Li?NiaCobMn(1?a?b)O2 (where 0<??1.15, 0.2?a?0.6, 0<b?0.8, and 0<(1?a?b)), a positive electrode active material particle B3 expressed by General Formula (B3): Li?+?Mn(2?a??)MeaO4 (where 0<??1.0, 0???0.3, 0?a?0.

Abstract: A rechargeable battery includes an electrode assembly and first and second lead tabs. The electrode assembly includes at least one separator between a first electrode and a second electrode. The first and second lead tabs are respectively connected to the first and second electrodes and are drawn out of a case. The electrode assembly includes a first assembly having a first length in a first direction and a second assembly having a second length in the first direction shorter than the first length. The first assembly includes at least one first uncoated tab protruding from the first electrode and connected to the first lead tab, and at least one second uncoated tab protruding from the second electrode and connected to the second lead tab. The second assembly includes the at least one second uncoated tab.

Abstract: A method for producing a positive electrode for a nonaqueous electrolyte secondary battery includes forming a positive electrode mixture layer on a positive electrode core, the positive electrode mixture layer containing hollow positive electrode active material particles having a BET specific surface area X of 1.5 m2/g or more; and compressing the positive electrode mixture layer. The ratio of the BET specific surface area Y of the positive electrode active material particles after the compression to the BET specific surface area X (Y/X) is between 1.05 and 1.35.

Abstract: A high energy density rechargeable metal-ion battery includes an anode energy layer, a cathode energy layer, a separator for separating the anode and the cathode energy layers, an anode current collector for transferring electrons to and from the anode energy layer, the battery characterized by a maximum safe voltage for avoiding overcharge, and an interrupt layer that interrupts current within the battery upon exposure to voltage in excess of the maximum safe voltage. The interrupt layer is between the anode energy layer and current collector. When unactivated, it is laminated to the cathode current collector, conducting current therethrough. When activated, the interrupt layer delaminates from the anode current collector, interrupting current therethrough.

Abstract: The present invention relates to an oxyhalide electrochemical cell comprising an anode of a Group IA metal and a cathode of a composite material prepared from a first electrochemically active carbonaceous material and a second electrochemically non-active carbonaceous material. The cathode material of the present invention provides increased discharge capacity compared to traditional lithium oxyhalide cells. In addition, the cathode material of the present invention is chemically stable which makes it particularly useful for applications that require increased rate capability in extreme environmental conditions such as those found in oil and gas exploration.

Abstract: A nitrogen-containing carbon material containing a nitrogen atom, a carbon atom, and a metal element X, in which the atomic ratio (N/C) of the nitrogen atom to the carbon atom is 0.005 to 0.3, the content of the metal element X is 0.1 to 20% by mass, and the average particle diameter is 1 to 300 nm.

Abstract: An anode material for a lithium ion battery, comprising an oxygen-containing carbon where oxygen is in the form of functional groups, the oxygen being distributed gradient from the surface to the inside of the carbon, and the carbon having an interlayer space d002 larger than 0.3357 nm; and a porous graphene layer covering the oxygen-containing carbon, the graphene being in the form of monolayer or few-layer graphene.

Abstract: The present invention relates to an electrode and a method for manufacturing the electrode, which are for maintaining the uniformity of the thickness of an electrode coating layer in the electrode. In addition, the present invention is characterized by including a preparation step for preparing an electrode foil, an attachment step for attaching an adhesive member onto a portion of the electrode foil, a coated part formation step for coating an active material onto the electrode foil, and an uncoated part formation step for forming an uncoated part on the electrode foil by removing the adhesive member along with the active material coated onto the adhesive member.

Abstract: Provided is an alkali metal-sulfur cell comprising: (a) a quasi-solid cathode containing about 30% to about 95% by volume of a cathode active material (a sulfur-containing material), about 5% to about 40% by volume of a first electrolyte containing an alkali salt dissolved in a solvent (but no ion-conducting polymer dissolved therein), and about 0.01% to about 30% by volume of a conductive additive wherein the conductive additive, containing conductive filaments, forms a 3D network of electron-conducting pathways such that the quasi-solid electrode has an electrical conductivity from about 10?6 S/cm to about 300 S/cm; (b) an anode; and (c) an ion-conducting membrane or porous separator disposed between the anode and the quasi-solid cathode; wherein the quasi-solid cathode has a thickness from 200 ?m to 100 cm and a cathode active material having an active material mass loading greater than 10 mg/cm2.

Abstract: A lithium secondary battery comprises a cathode active material including a first cathode active material particle having a concentration gradient region and a second cathode active material particle having a single particle structure, to obtain improved electrical performance and mechanical stability.

Abstract: Disclosed is an air cell with higher energy density than before. An air cell comprises an electrolyte solution containing a potassium hydroxide solution having a pH of 17.3 or more under a temperature condition of 23° C., an anode containing iron, and a cathode.

Abstract: A composite electrode is provided having a collector, the collector is coated with an electrode composition containing an active electrode material, a binding agent, and a conductivity additive such as conductive carbon black. The electrode composition has a concentration gradient along the direction of the electrode thickness in respect of the active electrode material and the conductivity additive, with the concentration gradient of the active electrode material increasing toward the collector, and the concentration gradient of the conductivity additive and the binder decreasing toward the collector. Two different methods of producing the composite electrode are also provided. A lithium-ion battery is further provided which includes a composite electrode having a collector, the collector is coated with an electrode composition containing an active electrode material, a binding agent, and a conductivity additive.

Abstract: A battery mounting structure to enhance rigidity of a vehicle body without increasing a vehicle weight is provided. The battery mounting structure comprises a pair of frame members extending longitudinally and a battery pack an all-solid battery having a cell stack. The battery pack is disposed between the frame members. The battery pack is connected to the frame member through a connection member.

Abstract: The negative electrode plate includes at least a negative electrode composite material layer. The negative electrode composite material layer has a density of 1.5 g/cm3 or more. The negative electrode composite material layer contains at least first particles, second particles and a binder. The first particles contain graphite particles and an amorphous carbon material. The amorphous carbon material is coated on the surface of each graphite particle. The second particles are made of silicon oxide. The ratio of the second particles to the total amount of the first particles and the second particles is 2 mass % or more to 10 mass % or less. The negative electrode plate has a spring constant of 700 kN/mm or more to 3000 kN/mm or less.

Abstract: An electrode of an energy storage device and methods of fabrication are provided which include: pyrolyzing a carbon-containing precursor to form a stabilized-carbonized material; and annealing the stabilized-carbonized material to form a structurally-modified activated carbon material. The structurally-modified activated carbon material includes a tunable pore size distribution and an electrochemically-active surface area. The electrochemically-active surface area of the structurally-modified activated carbon material is greater than a surface area of graphene having at least one layer, the surface area of the graphene having at least one layer being about 2630 m2 g?1.

Abstract: A lithium ion secondary battery having more improved cycle characteristics is provided. The present invention relates to a lithium ion secondary battery having a negative electrode comprising a graphite and a silicon oxide having a composition represented by SiOx (0<x?2), wherein AG/AS is within a range of 0.6 or more and 1.6 or less when a particle number average aspect ratio of the graphite is defined as AG and a particle number average aspect ratio of the silicon oxide is defined as AS.

Abstract: A high-capacity and a high-performance rechargeable battery is provided by forming a rechargeable battery stack that includes a spalled material structure that includes a spalled cathode material layer that has at least one textured surface and a stressor layer that has at least one textured surface. The stressor layer serves as a cathode current collector of the rechargeable battery stack. The at least one textured surface of the spalled cathode material layer forms a large interface area between the cathode and electrolyte which is formed above the spalled cathode material layer. The large interface area between the cathode and the electrolyte reduces interface resistance within the rechargeable battery stack.

Abstract: An electrode for a cell includes a resin current collector that is planate and contains a resin and an electrically conductive filler, and an electrode active material layer that is disposed on at least one surface side of the resin current collector and that contains electrode active material particles. The resin current collector includes an electrically conductive layer on its surface side facing the electrode active material layer, the electrically conductive layer having configuration with recesses and projections. This configuration with recesses and projections satisfies the relationship given by formula (1): h/tan ?<D, in which h is the average height of the configuration with recesses and projections, ? is the average inclination angle of the configuration with recesses and projections, and D is the average particle diameter of the electrode active material particles. A cell includes the electrode for a cell described above.

Abstract: Disclosed is a positive active material composition that includes a positive active material and an additive represented by the following Chemical Formula 1. L1-A1-L2-A2-L3-A3-(L5-A5)n-L4-A4??[Chemical Formula 1] In Chemical Formula 1, each substituent is the same as described in the detailed description.

Abstract: The present invention provides an electrode which is a zinc anode or an electrode of any other type, and ensures good durability and sufficiently high ion conductivity, and sufficiently improves the cell performance when used in a cell, and also provides its precursor. The present invention relates to an electrode which includes a current collector and an active material layer containing an active material, and further includes a specific anion conducting material or a specific solid electrolyte.

Abstract: A cathode material for a lithium-ion secondary battery including: granulated bodies in which primary particles are aggregated, wherein an average particle diameter of the granulated bodies is 0.90 ?m or more and 2.00 ?m or less, particle diameters of 90% or more of the granulated bodies are 0.25 ?m or more and 3.50 ?m or less, wherein particle diameters of the granulated bodies are evaluated such that 300 granulated bodies are randomly selected from a view of the granulated bodies using a scanning electron microscope, a plurality of diameters of each of the 300 granulated bodies that pass through a central point thereof are evaluated, and a maximum diameter selected from said plurality of diameters is considered as a particle diameter of each of the granulated bodies.

Abstract: An all-solid-state battery includes: a cathode substrate; a cathode portion; a solid electrolyte layer; an anode portion; and an anode substrate. The cathode portion includes a cathode active material, a first solid electrolyte, a conductive material, and a binder, the anode portion is configured by a first anode portion having a pore structure and a second anode portion having metal foil, and the first anode portion includes a second solid electrolyte, a conductive material, and a binder.

Abstract: A magnesium battery electrolyte with a wide electrochemical window was developed. The electrolyte includes an organic boron magnesium salt and an aprotic polar solvent. The organic boron magnesium salt is an organic boron magnesium salt complex formed by compounding a Lewis acid with a boron center and a magnesium-containing Lewis base R?2-nMgXn, wherein n is 0 or 1, R and R? respectively represent a fluoroaryl group, an alkylated aryl group, an aryl group, an alkyl group, or a pyrrolidinyl group, and X represents a halogen. The solvent is an aprotic polar solvent such as ether or a mixed solvent thereof. The concentration of the electrolyte is 0.25 to 1 mol/L, and the electric conductivity is 0.5 to 10 mS/cm. The electrolyte allows reversible deposition/dissolution of magnesium, features good cycling stability, and has a wide electrochemical window (>3.0V vs. Mg/Mg2+).

Abstract: A nonaqueous electrolyte secondary battery insulating porous layer usable as a member of a nonaqueous electrolyte secondary battery having an excellent cycle characteristic is provided. A nonaqueous electrolyte secondary battery insulating porous layer includes a thermoplastic resin, porosity of the nonaqueous electrolyte secondary battery insulating porous layer being not less than 25% and not more than 80%, and a ratio of a displacement amount of the nonaqueous electrolyte secondary battery insulating porous layer at tenth loading-unloading cycle to a displacement amount of the nonaqueous electrolyte secondary battery insulating porous layer at fiftieth loading-unloading cycle being not less than 100% and less than 115%.

Abstract: Ion transport in electrochemical cells or energy storage devices may take place in metal salt-based electrolytes. The metal salt-based electrolytes may comprise high doping metal salt formulations. Electrochemical cells or energy storage devices comprising metal salt-based electrolytes may be used as single-use or rechargeable power sources.

Abstract: A multiple-element composite material for negative electrodes, a preparation method therefor, and a lithium-ion battery using the negative electrode material. The lithium-ion battery uses multiple-element composite material for negative electrodes has a core-shell structure containing multiple shell layers. The inner core consists of graphite and nano-active matter coating the surface of the graphite. The outer layers of the inner core are in order: the first shell layer is of an electrically conductive carbon material, the second shell layer is of a nano-active matter, and the third shell layer is an electrically conductive carbon material coating layer.