Hydro-quebec

Dai-ichi Kogyo Seiyaku Co., Ltd.

Societe Nationale Elf Aquitaine

Fernand Brochu

Karim Zaghib

Abdelbast Guerfi

Michel Gauthier

Michel Duval

Kimio Kinoshita

Michel Armand

Monique Masse

Michel Bernard Armand

Alain Vallee

Michiyuki Kono

Tsutomu Sada

Jean-Michel Chabagno

Guy Vassort

Philippe Ricoux

Eriko Hayashi

Philippe Rigaud

Gabrielle Nadeau

Monique Massé

Monique MassÉ

Synthesis process for new particles of LiTiO, LiZTiOor LiZTiO, preferably having a spinel structure, wherein &#x3b2; is greater than 0 and less than or equal to 0.5 (preferably having a spinel structure), &#x3b1; representing a number greater than zero and less than or equal to 0.33, Z representing a source of at least one metal, preferably chosen from the group made up of Mg, Nb, Al, Zr, Ni, Co. These particles coated with a layer of carbon notably exhibit electrochemical properties that are particularly interesting as components of anodes and/or cathodes in electrochemical generators.

LiTiO, LiZTiOor LiZTiO, particles, processes for obtaining same and use as electrochemical generators

[object Object]

A method for modifying graphite particles having a prismatic shape or a cylindrical shape characterized by an edge function fe and a basal function fb, said method providing increase of the edge function and lowering of the basal function, wherein the method includes submitting the graphite particles to at least one physical means selected from attrition, jet mill, ball mill, hammer mill, or atomizer mill, in the presence of at least one chemical compound chosen from the group of compounds of the formula MF, in which M represents an alkaline or alkaline-earth metal and z represents 1 or 2, NaCl and NHF or a mixture thereof, said compound or compounds being added in solid form, at the beginning of the step using the physical means.

Potatolike shaped graphite particles with low impurity rate at the surface, process for preparing same

Modified graphite particles obtained from graphite or based on graphite, the said particles having impurities in their internal structure and having on the surface a low, even nil, rate of an impurity or several impurities. In addition, these particles have at least one of the following characteristics: These particles can be used for fuel cells, electrochemical generators, or as moisture absorbers and/or oxygen absorbers and they have important electrochemical properties. The electrochemical cells and batteries thus obtained are stable and safe.

Potato-shaped graphite particles with low impurity rate at the surface, method for preparing the same

Modified graphite particles are obtained from graphite or based on graphite. The particles have impurities in their internal structure and have on the surface a low, even nil, rate of an impurity or several impurities. In addition, these particles have at least one of the following characteristics: a tab density between 0.3 and 1.5 g/cc; a potatolike shape; and a granulometric dispersion such that the D90/D10 ratio varies between 2 and 5 and the particles have a size between 1 and 50 &#x3bc;m. These particles can be used for fuel cells, electrochemical generators, or as moisture absorbers and/or oxygen absorbers and they have important electrochemical properties. The electrochemical cells and batteries thus obtained are stable and safe.

Synthesis process for new particles of LiTiO, LiZTiOor LiZTiO, wherein &#x3b2; is &#x3e;0 and &#x2266;0.5, &#x3b1; is a number &#x3e;0 and &#x2266;0.33, Z is a source of at least one metal, preferably chosen from the group made up of Mg, Nb, Al, Zr, Ni, Co. These particles coated with a layer of carbon notably exhibit electrochemical properties that are particularly interesting as components of anodes and/or cathodes in electrochemical generators. The process may involve the steps of a) preparing a dispersion of a mixture of TiO&#x2014;LiY-carbon, wherein x is a number between 1 and 2, z is 1 or 2, and Y is a radical chosen among CO, OH, O and TiOor a mixture thereof; and 2) heating of the dispersion, preferably to a temperature of between about 400&#xb0; C. and about 1000&#xb0; C.

A process for synthesizing particles of an oxide corresponding to a formula selected from: LiTiO; LiZTiO; and LiZTiO, said process including the steps of: a) preparing an intimately dispersed ternary mixture of TiO&#x2014;LiY-carbon, wherein x is a number between 1 and 2, z is 1 or 2, Y is a radical chosen from the group consisting of CO, OH, O and TiOor a mixture thereof, and the carbon is a carbon powder selected from the group consisting of natural or artificial graphite, carbon black, Shawinigan black, Ketjen black and cokes; b) heating the dispersion at a temperature of between 400 and 1,000&#xb0; C.; and c) if appropriate, adding a source of at least one metal Z to the ternary mixture, wherein the operating conditions are chosen in such a way as to yield a conversion of the initial products respectively into LiTiO, LiZTiO, LiZTiO.

Li4Ti5O12, Li(4-&#x3b1;)Z&#x3b1;Ti5O12 or Li4Z&#x3b2;Ti(5-&#x3b2;O12 particles, processes for obtaining same and use as electrochemical generators

The present invention relates to the physical or chemical specific purification of natural mineral graphite. This purification is preferably applied to the surface of natural graphite in order to allow the formation of a passivation film during the first electrical discharge or the insertion of lithium in the graphite when the latter is used in a lithium-ion cell. The grinding to a small size before purification allows the optimization of the distribution of the particles, resulting in a more uniform electrode. This grinding is carried out in the presence of the natural impurities of the graphite that play the role of a micro-abrasive and result in a hardness of the graphite that increases its mechanical properties.

Surface preparation of natural graphite and the effect of impurities on grinding and the particle distribution

A composition for applying a coating on a support at low temperature from a dispersion of at least a component of the coating to be deposited in the composition. The composition includes at least a strong and heavy solvent with a boiling point higher than 150&#xb0; C. approximately, and a weak solvent with a boiling point less than 100&#xb0; C. approximately. The solvents forming the composition must constitute a mixture that evaporates at a temperature less than 100&#xb0; C. The composition is particularly useful for forming electrodes or electrolyte in lithium-ion batteries. The method and the device used for forming the coating use a dispersion spreader and an infrared lamp.

Graphite and cobalt oxide-containing composition and device for applying a coating on a support

Graphite has a lubricating property resulting from its laminar structure in two planes, basal and edge plane. The basal plane is hydrophobic. The use of graphite or carbon treated at high temperature in a composite or coating (paint) whereof the privileged orientation of particles is basal enables to cause the coating to be water-repellent. Said property enables to prevent or reduce ice accumulation as well as corrosion on electrical installations.

Hydrophobic composition and use on a substrate for preventing ice formation and corrosion

Polymer electrolyte compositions for lithium electrochemical generators of the LPB type (lithium polymer electrolyte battery), comprising a mixture of polymers wherein one of the components has a high molecular weight, such as those used currently in LPB batteries, and wherein the other component is a low molecular weight polymer resulting in a more efficient and faster multi-dimensional cross-linking by irradiation, so as to give a network which is interpenetrated or not and films of electrolyte being have better mechanical properties and lower thicknesses, while preserving the good properties of adhesion on the electrodes and the choice of the coating techniques.

LPB electrolyte compositions based on mixtures of copolymers and

Preparation of an electrolyte film for lithium/polymer electrolyte batteries by extruding a powder mixture containing a polymer, a lithium salt and an additive consisting of an ultra fine powder of a metal oxide, such as silica, aluminum, or titanium oxide with a particle size between about 7 and 40 nm. The role of the additive is to prevent the formation of adhesive solid blocks in the powder mixture and to allow the introduction of this mixture in the extruder. Electrolyte compositions, electrolytes as well as electrochemical generators obtained according to the invention are also described.

Additives for extruding polymer electrolytes

To prepare polymer dispersions containing large quantities of solid particles, with at least some of these consisting of materials with a high specific area (&gt;50 m.sup.2 /g) or oil absorption capacity, the mixture of particles is first co-ground in a non polar solvent. The co-ground mixture is dried until obtaining a dry powder of reagglomerated particles, which is dispersed in a solution containing a polymer and possibly a salt. Large quantities of solid particles can thus be dispersed while maintaining adequate rheological properties for the dispersion, and low porosities and few surface defects in the films obtained by coating the dispersion. This process can be used to prepare thin films of positive electrode for lithium polymer batteries, as well as in the paint, coatings and magnetic tape industry.

Growing community of inventors

Longueuil, Canada

Fernand Brochu