FR2911723A1 - Electrode, for electrochemical energy storage system, which is useful as a battery for a computer, a server/a portable telephone, or a supercapacitor, comprises a triazinic polynitroxide - Google Patents

Abstract

Electrode for electrochemical energy storage system, comprises at least a triazinic polynitroxide (a). An independent claim is included for an electrochemical energy storage system comprises at least a positive electrode, a negative electrode and an electrolyte, where the material constituting the positive and negative electrodes includes (a).

Description

Electrode comprising at least one triazine polynitroxide

  The present invention relates to an electrochemical energy storage system electrode comprising at least one triazine polynitroxide. It also relates to an electrochemical energy storage system comprising such an electrode, as well as the use of at least one triazine polynitroxide for the manufacture of an electrochemical electrode storage electrode electrode.

  We know::. lithium batteries or batteries operating according to the principle of the migration of lithium ions, in the discharge phase, of a negative electrode (or anode), nc but based on carbon / graphite, towards a positive electrode ( or cathode) containing a lithium insertion compound, generally metal oxide type, through an ionic conductive electrolyte.

  The passage of lithium ions in the internal circuit of the accumulator is compensated by the migration of a corresponding number of electrons in the external circuit, thereby generating an electric current. The accumulator can then be recharged, which has the effect of reintegrating the lithium ions into the negative electrode. The electrons circulate in the same direction as the lithium ions, thus causing oxidation of the negative electrode in the discharge phase and oxidation of the positive electrode in the charging phase.

  It has been proposed in US Pat. No. 2003/0096165 to use a nitroxyl radical-type compound or polymer to form at least one of the electrodes of a battery of the above type. An example of a free-radical polymer is a 2,2,6,6-tetramethyl piperidine-1-N-oxyl polyester (TEMPO).

  It has also been suggested to use a TEMPO polyester as a cathode by NAKAHARA K. et al, Rechargeable 3atteries with Organic Radical Cathodes, Chem. Phys. Lert. 359 (2002) 351-354.

  There is still a need, however, to provide electrochemical energy storage systems, such as rechargeable batteries, with fast charge / discharge kinetics, high power and energy density, and low cost, non-toxic to the environment. user = ~ t respect the environment.

  The Applicant has now discovered that this need can be satisfied by using triazine polynitroxides to form at least one of the electrodes of the electrochemical system.

  Some of these polymers are already known as catalysts for selective oxidation of aliphatic and benzylic primary and secondary alcohols, aldehydes and ketones (Dijksman A. et al., Chem Commun 2000, 271-272).

  However, to the knowledge of the Applicant, it has never been suggested to use them for the manufacture of electrodes of electrochemical energy storage systems.

  The present invention therefore relates to an electrochemical energy storage system electrode comprising at least one triazine polynitroxide.

  It also relates to an electrochemical energy storage system comprising at least one positive electrode, at least one negative electrode and an electrolyte, characterized in that the material constituting the positive electrode and / or the negative electrode comprises at least one triazine polymer.

  By triazine nynynitroxide, is meant a homo- or copolymer comprising at least one carrier monomer at least 1 of a triazine group and a nitroxyl radical.

  Furthermore, it is understood that the expression between the following appearing in the remainder of this description .do't be understood as including the aforementioned terminals.

  The polymer (triazinic polynitroxide) used according to the invention is capable of being obtained from the corresponding secondary polyarriene, which is generally a HALS-type polyamine (Hindered-Amine Light Stabilizer or amine-light stabilizer). sterically hindered), according to a process preferably comprising the following steps: - the solubilization of the secondary polyamine in an organic solvent immiscible with water ,. such as dichloromethane, -addition of water to obtain a biphasic medium, -addition to biphasic medium, with vigorous stirring: (a) an aliphatic peracid, for example acetic acid peracid, according to a peracidic molar ratio secondary amine preferably ranging from 1.5 to 2.5 and (b) a sufficient amount of a basic aqueous solution, such as a potassium carbonate solution, to obtain a pH of the aqueous phase of biphasic medium ranging from 4 to at 12, the temperature of this stage preferably being between -10 ° C. and + 40 ° C., the recovery of the organic phase, advantageously by decantation, and the elimination of the organic solvent, for example by evaporation under pressure. scaled down.

  The secondary polyamine starting can be available in: commerce, in which case the polymer according to the invention also has the advantage of being simple and inexpensive to manufacture, or be obtained itself by a method of synthesis.

  According to a particular embodiment, the triazine polynitroxide used according to the invention contains at least one monomer carrying a 2,2,6,6-tetraalkylpiperidine-N-oxyl radical (said monomer may or may not be in the group). triazine), where the alkyl group contains from 1 to 4 carbon atoms.

  According to a preferred embodiment of the invention, the secondary polyamine used in the above process contains at least one monomer containing a 2 - [(2,2,6,6) -tetraalkyl-4-piperidinyl] - group. amino-1,3,5-triazine.

  More specifically, it is preferred that this polyamine has the formula (I) R X R5 ùz R5., 'Y (I)

  wherein: z is an integer from 2 to 2C; R3 represents a hydrogen atom; X represents an oxygen atom or a group -NR4-; R 4 represents, simultaneously or independently, a hydrogen atom, a 2,2,6,6-tetramethyl-4-piperidinyl group of a linear, branched or cyclic, saturated or unsaturated C 1 -C 15 hydrocarbon group, said group hydrocarbon containing one or two oxygen or nitrogen atoms, or two groups R4, bonded to the same nitrogen atom, can be bonded together to form a 5- to 7-membered heterocyclic ring and may additionally contain an atc ) oxygen; R5 represents, simultaneously or independently, a hydrogen atom or a group -NR62, or both R5 are each NRaRb or Ra is a (2, 2, 6, 6) -tetramethyl-4-piperidinyl group and both substituents Rb together form a tr: iazine group substituted with -NR42; R6 represents, simultaneously or independently, a hydrogen atom, a linear, cyclic or saturated, saturated or unsaturated C1-C20r hydrocarbon group, a 2,2,6,6-tetramethyl-4-piperidinyl group or a group of formula (II). wherein R 7 represents, simultaneously or independently, a hydrogen atom, a linear or branched C1-C12 alkyl group or a 2, 2, 6, 6-tetramethyl-4-piperidinyl group and Y represents, simultaneously or independently, a linear, branched or cyclic C 1 -C 20 alkylene group may include one or two oxygen or nitrogen atoms. According to a particularly preferred embodiment of the invention, the secondary polyamine has the formula (II = -) below: ## STR5 ## ~ \ N - (CH2) m It N z in lac_- ~ 11e z represents: ~ te an integer ranging from 2 to 10; m represents: .te an integer ranging from 2 to 12; R3 is a hydrogen atom; R4 represents, simultaneously or independently, a hydrogen atom, a 2,2,6,6-tetramethyl-4-piperidinyl group or; a linear or branched C1-C10 alkyl or alkenyl group, or two R4 groups, bonded to the same nitrogen atom, may be bonded together to form a 6-membered heterocyclic ring which may contain an oxygen atom; and R 8 represents, simultaneously or independently, a hydrogen atom, a 2,2,6,6-tetramethyl-4-piperidinyl group or a linear or laminated C 1 -C 6 alkyl or alkenyl group, or a group of formula ( II) as defined above, or those R8 groups together form a triazine group substituted with a group -NR42 where R4 is as defined above.

  In a particularly preferred manner, the polyamine corresponds to the formula (III) in which: m is 6; one of R4 is hydrogen and the other is tC8-H1-7; and R8 is a hydrogen atom.

  A polyamine of this type having a number-average molecular weight of about 3000 is especially commercially available from CIBA under the trade name CH: [MASSORB® 944.

  According to another possibility, the polyamine used according to the invention corresponds to formula (III) in which: m is 6; one of R4 is C4H9 and the other is 2,2,6,6-tetramethyl-4-piperidinyl; R8 is a hydrogen atom.

  According to another possibility, the polyamine used according to the invention corresponds to formula (III) in which: m vLut 6; the R 4 groups together form a saturated six-membered heterocyclic ring containing an oxygen atom; and R8 is a hydrogen atom.

  These compounds, identified by references 27, 28 and 29 in the publication of Kirchhoff J. et al., Polymers & Palymer Composites, Vol. 8, No. 4, 2000, are commercially available from DEGUSSA-HOLSä

  According to another possibility, the polyamine used according to the invention corresponds to formula (III) in which: m is 6; the two R8 groups together form a triazine rump substituted with a group -NR42; and each R4 group forms with that present on the same carbon atom a saturated six-membered heterocyclic ring containing an oxygen atom.

  According to another possibility, the polyamine used according to the invention corresponds to formula (III) in which m is 6; one of the R4 groups is a hydrogen atom and. the other is 1,1-dimethyl-3,3-dimethylbutyl; and the two R8 groups together form a triazine group substituted with a group -NR42 where one of the R4 groups is a hydrogen atom and the other is a 1,1-di-im, 3,3-thyl group. dimethyl-butyl.

  Polyamines of this type are described in particular in application WO 02/058844 and one of them is commercially available from CIBA under the trade name CHI: MASSORB 966.

  The implementation of the preferred method described above on the CHIMASSORB 944 polyamine makes it possible precisely to obtain the triazine polynitroxide described in Example 4 of application WO 00/40550, having a number-average molecular weight ranging from 2000 to 3100. This polymer, known under the designation PIPO (for immobilized polyamine immobilized piperidinyl OXyl or immobilized polyamine based piperidinyl oxide), identified by the CAS number 91993-31-6, is especially available commercially from the company ARKEMA under the trade name OXYNITROX "S100.

  The polymer according to the invention can be used as constituent material of one or both electrodes, scit alone, or in combination with an additional conductive material such as graphite (preferably in the form of fibers), carbon black, acetylene black, polyaniline, polypyrrole, polythiophene, polyacetylene, polyacene and mixtures thereof. The electrode containing this polymer may further contain at least one binder such as poly (tetrafluoroethylene).

  The polymer can be used according to the invention in the constituent material of the positive electrode where it will be oxidized to oxoammonium ion during the charging of the electrochemical system. During the discharge, the nitroxide radical is regenerated by reduction of oxoammonium. In this case, the anode may consist of, for example, carbon and / or graphite or lithium metal. Alternatively, this polymer may be used in the constituent material of the negative electrode where it will be oxidized to the corresponding oxoammonium cation during the discharge of the electrochemical system. In this case, the positive electrode may consist of, for example, a metal oxide.

  Generally, the electrodes of the electrochemical energy storage system according to the invention are each ergo-contact, by their side opposite to that of the electrolyte separating them, with a current collector which may for example consist of a plate metal based on nickel, aluminum, aluminum alloy, copper, gold, silver or stainless steel.

  Any type of electrolyte may be used and preferably one or more organic solvents containing at least one salt containing a cation such as lithium ion. Examples of such salts are in particular those having the formula: LiPF6r LiClO4, LiBF4, LiCF3SO3, LiN (CF3SO2) 2, LiN (C2F5SO2) 2, LiC (CF3SO2) 3 and LiC (C2F5SO2) 3.

  The electrochemical energy storage system according to the invention can in particular be a battery or a supercondensate. The battery can for example be used as backup battery for different applications, especially in personal computers, computer servers or mobile phones. The supercondenser may also be used to supply the secondary electrical circuits of a vehicle or to preheat catalytic converters.

  The present invention therefore also relates to the use of an electrochemical energy storage system such as previously described as backup battery of a personal computer, a computer server or a mobile phone.

  It also relates to the use of at least one triazine polynitroxide for the manufacture of an electrode for electrochemical energy storage system such as a battery.

  The invention will now be illustrated by the following non-critical examples.

EXAMPLES

  EXAMPLE 1 Manufacture of an Electrode Containing a Triazine Polynitroxide A glove box equipped with an air purifier is mixed in: 60 mg of a copolymer of vinylidene chloride and of hexafluoropropylene and 140 mg of a solution electrolyte consisting of a 1: 1 mixture of ethylene carbonate / propylene carbonate containing 1 mol / l of LiPF6, under an apgon atmosphere. 1130 mg of tetrahydrofuran are added to the mixture and the mixture is dissolved to prepare an electrolyte gel solution in tetrahydrofuran.

  30 mg of OXYNITROX ™ S100 (ARKEMA), followed by 60 mg of graphite powder and 200 mg of the electrolyte gel prepared as described above, are mixed in a separate container, and 1000 mg of tetrahydrofuran is added to the mixture to give To obtain a homogeneous black slurry, 200 mg of this slurry is then added dropwise to the surface of an aluminum foil (surface 1.5 x 1.5 cm, thickness 100 μm) and spread to obtain a The surface is allowed to stand at room temperature for 60 minutes to evaporate the solvent, and thus form an organic layer containing the triamine oxide on the aluminum foil.

  At the same time, 600 mg of a copolymer of vinylidene chloride and hexafluoropropylene, 1400 mg of an electrolyte solution, consisting of a 1: 1 mixture of ethylene carbonate / propylene carbonate containing 1 mol 1 of LiPF6, and 11.3 g of tetrahydrofuran. This mixture is applied to a glass plate up to a thickness of 1 mm. The solvent was allowed to evaporate for one hour to obtain an electrolyte gel film having a thickness of 150 μm on the glass plate.

  The electrolyte gel film is decocessed into 2.0 x 2.0 cm squares and strat_fied on the aluminum foil on which the triazine polynitroxide layer has been deposited. The sheet is then laminated with a copper foil provided with a lithium film (30 μm thick: gym for the lithium film and 20 μm for the copper foil). The product is sandwiched between two sheets of polytetrafluoroethylene having a thickness of 5 mm and is pressed to obtain a battery whose positive electrode contains triazine polynitroxide and the negative electrode consists of the copper foil provided with the film of lithium.

  Example 2 Manufacture of an Electrode Containing a Triazine Polynitroxide

  A polymer based on triazine polynitroxide (O: / YNITROX S100 from ARKEMA) is mixed with 20-50% by weight of graphite fibers having a diameter of 150 nm to obtain a positive electrode in which the graphite fibers are covered with a thin layer (50-100 nm) of polymer. This electrode is stacked with a separation film and a negative electrode made of lithium metal or graphite carbon. Ethylene carbonate containing LiPF 6 is used as the electrolyte. This gives a lithium battery.

Claims (15)

  1. Electrode: An electrochemical energy storage system dde comprising at least one triazine polynitroxide.   2. An electrochemical energy storage system comprising at least one positive electrode, at least one negative electrode and an electrolyte, characterized in that the material forming the positive electrode and / or the negative electrode comprises at least one triazine polynitroxide.   3. Electrochemical energy storage system according to claim 2, characterized in that it is a battery or a supercapacitor.   4. Elec: r) or electrochemical energy storage system according to any one of claims 1 to 3, characterized in that the triazine polynitroxide contains at least one monomer bearing a radical 2,2,6,6- tetraalkyl peridine-N-oxyl (said monomer may or may not be triazine group-sorting), wherein the alkyl group contains 1 to 4 carbon atoms.   5. Elec'nri)) or electrochemical energy storage system according to any one of claims 1 to 4, characterized in that the triazine polynitroxide is obtainable from the corresponding secondary polyamine, according to a Process comprising the following steps: - solubilization of the secondary polyamine with a water-immiscible organic solvent, such as dichloromethane, -the addition dre.Lu to obtain a biphasic medium, - the addition to the medium biphasic, with vigorous stirring: (a) an aliphatic peracid, for example acetic acid peracid, in a peracid / secondary amine molar ratio preferably ranging from 1.5 to 2.5 and (b) a sufficient amount of an aqueous solution basic, such as a solution of potassium carbonate, to obtain a pH of the aqueous phase of biphasic medium ranging from 4 to 12, the temperature of this step being preferably between -10 C and +40 C, - recovery of the organic phase, advantageously by decantation, and the removal of the organic solvent, for example by evaporation under reduced pressure.   Electrochemical system or electrochemical energy storage system according to claim 5, characterized in that the secondary polyamine contains at least one monomer containing a 2 - [(2,2,6,6) -tetraalkyl-4- group). piperidinyl] - amine-1,3,5-triazine.   Electrochemical electrode or electrochemical energy storage system according to claim 5, characterized in that the polyamine corresponds to the formula (I): ## STR2 ## in which: z represents a integer from 2 to 20; R3 represents a hydrogen atom; X represents an oxygen atom or a group -NR4-; R 4 represents, simultaneously or independently, a hydrogen atom, a 2,2,6,6-tetramethyl-4-piperidinyl group or a linear, branched or cyclic, saturated or unsaturated C 1 -C 15 hydrocarbon-based group, said hydrocarbon group may contain one or two oxygen or nitrogen atoms, or two R4 groups, bonded to the same nitrogen atom, may be bonded together to form a 5- to 7-membered heterocycle which may contain an oxygen atom; R5 represents, simultaneously or independently, a hydrogen atom or a group -NR62 or both R5 are each NRaRb where Ra is a group (2,2,6,6) -tetramethyl-4-piperidinyl and the two substituents Rb form together a triazine group substituted with a group -NR42; R 6 represents, simultaneously or independently, a hydrocene atom, a linear, cyclized or cyclic, saturated or unsaturated C 1 -C 20 hydrocarbon-based group, a 2,2,6,6-tetramethyl-4-piperidinyl group or a group of formula (II). RR7 wherein R7 represents, simultaneously or independently, a hydrogen atom, a linear or branched C1-C12 alkyl group or a 2,2,6,6-tetramethyl-4-piperidinyl group; and Y represents, simultaneously or independently, a linear, branched or cyclic C 1 -C 20 alkylen group which may comprise one or two oxygen or nitrogen atoms. 15   Electrochemical electrode or electrochemical energy storage system according to Claim 7, characterized in that the secondary polyamine corresponds to the following formula (III): in which: z represents an integer ranging from 2 to 10; m represents an integer from 2 to 12; R3 is a hydrogen atom; R4 represents, simultaneously or independently, a hyd-oenene atom, a 2,2,6,6-tetramethyl-4-piperidinyl group or a linear or branched C1-C10 alkyl or alkenyl group, or two R4 groups , linked to the same nitrogen atom, may be bonded together to form a 6-membered heterocyclic ring which may contain an oxygen atom; and R 8 represents, simultaneously or independently, a hydrogen atom, a 2,2,6,6-tetramethyl-4-piperidinyl group or a linear or branched C1-C10 alkyl or alkenyl group, or a group of formula ( II) as defined above, or two R8 groups together form a triaz = 1_ne group substituted by a -NR42 group where R4 is as defined o.reviously.   Electrochemical electrode or electrochemical energy storage system according to claim 8, characterized in that the polyamine has the formula (III) wherein m is 6; one of R4 is hydrogen and the other is tC8-H17; and R8 is a hydrogen atom.   10. Electrode or electrochemical system of selo energy storage. claim 8, characterized in that the polyamine has the formula (III) wherein m is 6; one of these R4 groups is C4H9 and the other is 2,2,6,6-tetramethyl-4-piperidinyl; and R8 is a hydrogen atom.   Electrochemical electrode or electrochemical energy storage system according to claim 8, characterized in that the polyamine has the formula (III) wherein m is 6; the R 4 groups together form a saturated six-membered heterocyclic ring containing an oxygen atom; and R8 is a hydrogen atom.   Electrochemical electrode or electrochemical energy storage system according to claim 8, characterized in that the polyamine corresponds to formula (III) in which: m is 6; the two R8 groups together form a triazine group substituted with a group -NR42; and each R4 group forms with that present on the same carbon atom a saturated six-membered heterocyclic ring containing an oxygen atom.   Electrochemical electrode or electrochemical energy storage system according to claim 8, characterized in that the polyamine corresponds to the formula (II: I) in which: mvaut 6; one of R4 is hydrogen and the other is 1,1-dimethyl-3,3-dimethylbutyl; and the two R8 groups together form a triazine group substituted with a group -NR42 where one of the R4 groups is. one hydrogen atom and the other is a 1,1-dimethyl-3,3-dimethylbutyl group.   14. Use of at least one triazine polynitroxide as defined in any one of claims 1 to 13 for the manufacture of an electrode electrochemical energy storage system.   15. Use of an electrochemical energy storage system according to any one of claims 1 to 13 as backup battery of a personal computer, a computer server or a mobile phone.