The present invention provides a negative electrode of lithium ion secondary battery, a preparation method thereof and a lithium ion secondary battery. The negative electrode of the lithium ion secondary battery comprises a negative electrode active material, a pre-lithiated conductive layer and a negative electrode current collector. By using the negative electrode of lithium ion secondary battery, the preparation method thereof and the lithium ion secondary battery of the present invention, technical effects of excellent electrochemical performance, especially excellent first discharge capacity and first time efficiency are achieved, and excellent negative electrode plate binding force is achieved.

The present invention is directed to a method of coating an electrical current collector comprising treating a portion of a surface of the electrical current collector with an adhesion promoting composition to deposit a treatment layer over the portion of the surface of the electrical current collector, wherein the resulting surface of the electrical current collector comprises (a) a treated portion comprising the treatment layer and (b) a non-treated portion that lacks the treatment layer; electrodepositing an electrodeposited coating layer from an electrodepositable coating composition onto the surface of the electrical current collector to form a coated electrical current collector; and rinsing the coated electrical current collector, wherein the electrodeposited coating layer substantially adheres to the treated portion of the surface and does not adhere to the non-treated portion of the surface. Also disclosed are electrodes and electrical storage devices.

A method for manufacturing a lithium ion battery with a capacitance greater than 1 mA h, including the deposition of at least one dense layer, which can be an anode and/or a cathode and/or an electrolyte, by a method of depositing a dense layer. The method includes: supplying a substrate and a suspension of non-agglomerated nanoparticles of a material P; depositing a layer on the substrate using the suspension; drying the layer thus obtained; densifying the dried layer by mechanical compression and/or heat treatment. The method of depositing being characterised in that the suspension of non-agglomerated nanoparticles of material P includes nanoparticles of material P having a size distribution, said size being characterised by the value of D50 thereof, such that: the distribution includes nanoparticles of material P of a first size D1 between 20 nm and 50 nm, and nanoparticles of material P of a second size D2 characterised by a value D50 at least five times less than that of D1, or the distribution has a mean size of nanoparticles of material P less than 50 nm, and a standard deviation to mean size ratio greater than 0.6.

A composition comprises: an at least partially hydrolysed polyvinyl acetate component having an hydrolysation degree of at least 5%; a polyalkylene glycol component having a number average molecular mass Mn lower than 9000 g/mol and consisting of one or more substances selected from the group consisting of polyethylene glycol, polypropylene glycol, copolymers of ethylene glycol and propylene glycol, and their derivatives; a positive or negative electrode active component; and a conductive component; wherein the mass ratio between the at least partially hydrolysed polyvinyl acetate component and the positive or negative electrode active component equals at least 0.12 and at most 0.30, and wherein the mass ratio between the polyalkylene glycol component and the positive or negative electrode active component equals at least 0.012 and at most 0.10.

A graphene composite film is produced for application to the anode of a battery. A graphene dispersion is peeled off of a graphite solvent mixture ultrasonically. The graphene material is then mixed with organic amine salt to be charged. Electrophoretic deposition is used to turn the graphene into a film. The film is then passed through a heat treatment to remove the organic amine salt. The resulting film is a highly conductive graphene film with a two-dimensional structure.

The present invention is directed towards an electrodepositable coating composition comprising (a) a fluoropolymer; (b) an electrochemically active material and/or electrically conductive agent; (c) a pH-dependent rheology modifier; and (d) an aqueous medium comprising water; wherein water is present in an amount of at least 45% by weight, based on the total weight of the electrodepositable coating composition. Also disclosed herein is a method of coating a substrate, as well as coated substrates and electrical storage devices.

The present invention provides a method for concurrent electrophoretic deposition (EPD) of a membrane-electrode assembly (MEA) comprising a first MEA electrode and a second MEA electrode. The method comprises electrophoretically depositing the first MEA electrode from a suspension comprising a first precursor on a first surface of an ion permeable membrane and electrophoretically depositing the second MEA electrode from a second suspension comprising a second precursor on a second surface of the ion permeable membrane, wherein the first precursor is physically separated from and ionically connected to the second precursor by the membrane.

A method for manufacturing a dense layer that includes: supplying a substrate and a suspension of non-agglomerated nanoparticles of a material P; depositing a layer on the substrate using the suspension; drying the layer thus obtained; and densifying the dried layer by mechanical compression and/or heat treatment. The method is characterised in that the suspension of non-agglomerated nanoparticles of material P includes nanoparticles of material P having a size distribution having a value of D50. The distribution includes nanoparticles of material P of a first size D1 between 20 nm and 50 nm, and nanoparticles of material P of a second size D2 characterised by the value D50 being at least five times less than that of D1, or the distribution has a mean size of nanoparticles of material P less than 50 nm, and a standard deviation to mean size ratio greater than 0.6.

The present invention is directed to electrodepositable compositions comprising: (a) an aqueous medium; (b) an ionic resin; and (c) solid particles comprising: (i) lithium-containing particles, and (ii) electrically conductive particles, wherein the composition has a weight ratio of the solid particles to the ionic resin of at least 17:1, and wherein the weight ratio of the lithium-containing particles to the electrically conductive particles is at least 3:1. The present invention is additionally directed to a battery electrode comprising a substrate and a coating applied to a surface of the substrate. The coating is deposited from the electrodepositable composition described above.

Graphene electrodes-based supercapacitors are in demand due to superior electrochemical characteristics. However, commercial applications have been limited by inferior electrode cycle life. A method to fabricate highly efficient supercapacitor electrodes using pristine graphene sheets vertically-stacked and electrically connected to the carbon fibers which results in vertically-aligned graphene-carbon fiber nanostructure is disclosed. The vertically-aligned graphene-carbon fiber electrode prepared by electrophoretic deposition possesses a mesoporous three-dimensional architecture which enabled faster and efficient electrolyte-ion diffusion with a specific capacitance of 333.3 F g.sup.−1. The electrodes have electrochemical cycling stability of more than 100,000 cycles with 100% capacitance retention. Apart from the electrochemical double layer charge storage, the oxygen-containing surface moieties and α-Ni(OH).sub.2 present on the graphene sheets enhance the charge storage by faradaic reactions. This enables the assembled device to provide a gravimetric energy density of 76 W h kg.sup.−1 with a 100% capacitance retention even after 1,000 bending cycles.