CN101065864A

CN101065864A - Lithium primary battery and method for producing same

Info

Publication number: CN101065864A
Application number: CN 200580040597
Authority: CN
Inventors: 森垣健一; 山中晋; 人见徹; 藤井慎二; 池畠敏彦
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2004-11-26
Filing date: 2005-10-07
Publication date: 2007-10-31
Anticipated expiration: 2025-10-07
Also published as: CN100514720C

Abstract

Disclosed is a lithium primary battery comprising a positive electrode, a negative electrode, an organic electrolyte solution and a separator interposed between the positive electrode and the negative electrode. The negative electrode contains a negative electrode active material, and the negative electrode active material is composed of at least one substance selected from the group consisting of lithium metal and lithium alloys. At least the surface layer of the negative electrode is composed of a composite material of an amorphous carbon material and the negative electrode active material, and the surface layer is arranged opposite to the positive electrode via the separator.temperatures.

Description

Lithium primary battery and preparation method thereof

Technical field

The present invention relates to comprise the lithium primary battery of following negative pole, described negative pole comprises and is selected from least a in lithium metal and the lithium alloy as the lithium primary battery of negative active core-shell material and particularly relate under the low temperature under the heavy-current discharge performance and high temperature the lithium primary battery of at least one aspect excellence in the storage characteristics.

Background technology

Have high voltage and high-energy-density because use lithium metal or its alloy to compare with traditional aqueous solution type battery, so realize that easily size is dwindled and weight saving as the lithium primary battery of negative active core-shell material.Therefore, lithium primary battery is used for many purposes, for example as the main power source of compact electronic device with as backup battery.

For the positive electrode active materials of lithium primary battery, generally use metal oxide for example manganese dioxide and fluorographite.Use the battery of manganese dioxide to compare with those, be especially excellent aspect the lithium primary battery that uses fluorographite stable under longer-term storage and high temperature range, and can in wide temperature range, use.

But,, require further to improve the performance of lithium primary battery along with electronic installation become multifunction and miniaturization more.Especially, in the main power source of the electronic installation on being installed in automobile and the situation of backup battery, in the temperature range from low temperature to high temperature (approximately-40 ℃ to about 125 ℃), need enough discharge performances.When discharging under big electric current, lithium primary battery shows distinctive voltage decline in the discharge starting stage, and voltage increases gradually then.In the lithium primary battery that uses fluorographite, the degree that voltage descends in the starting stage is high, when especially discharging in low temperature range.

One of factor that discharge performance descends under the low temperature is the organic bath viscosity change.The viscosity that is used as the γ-Ding lactones (γ BL) of electrolytical solvent increases at low temperatures.Therefore, electrolytical ionic conductance reduces at low temperatures.Advised using mixing and had low boiling and low viscous 1, the solvent mixture that 2-dimethoxy-ethane and γ-Ding lactones forms with 1: 1 volume ratio.In this case, discharge voltage increases under low temperature range approximately-20 ℃, shows improved action.But, in this battery, the degree height that gas produces when storage under about 100 ℃ high temperature.Therefore, cell expansion during the high temperature storage and shortcoming that can not regular picture are arranged.

In addition, in lithium primary battery, high temperature storage has down increased internal resistance.Therefore, when for example at high temperature during the battery discharge of for example about 125 ℃ of storages, just the voltage after the discharge descends and becomes violent.

When by at-20 ℃ or when more the low temperature discharge under the low temperature is measured anodal polarization and negative pole polarization, in the discharge starting stage, the degree of polarization in the negative pole becomes than height in the positive pole.Equally, in the battery that high temperature storage is crossed, the degree of polarization in the negative pole uprises.Therefore, by reducing the reaction overvoltage of negative pole, can improve low-temperature characteristics and high-temperature storage characteristics greatly.

In the lithium secondary battery field,, the surface modification of the negative pole that comprises the lithium metal is studied in order to improve charging and exoelectrical reaction.Especially, in order to reduce the generation of dendrite, advised on negative terminal surface, forming the coating (patent documentation 1 and 2) of carbon containing.

But in the primary cell that does not charge, the generation of dendrite is not primary big problem.In addition, by discharge lithium metal from its surface melting.Therefore, even for the surface modification of negative pole has formed film or layer, but they separate when discharge.Therefore, do not attempt basically the process for modifying surface in the lithium secondary battery anode is applied in the primary cell.

Patent documentation 1: TOHKEMY Hei 6-168737 number

Patent documentation 2: TOHKEMY Hei 10-172540 number

Summary of the invention

The problem to be solved in the present invention

Lithium primary battery especially uses fluorographite to make its anodal lithium primary battery, shows as under heavy-current discharge, and discharge starting stage voltage descends greatly and increased gradually afterwards.Especially under 0 ℃ or lower low temperature environment in the situation of heavy-current discharge, the voltage drop of discharge starting stage is significant.In addition, when at high temperature storing lithium primary battery, the internal resistance of cell increases mainly due to the increase of negative pole interface resistance (from the resistance of electrolyte catabolite film).Therefore, in discharge after this, the degree of the voltage drop after and then beginning to discharge just becomes violent.Especially using manganese dioxide to do under the situation of anodal lithium primary battery, when battery was at high temperature stored after partial discharge, the increase of internal resistance and the decline of discharge performance became remarkable.Think that this is because Mn ³⁺Be disproportionated into Mn ⁴⁺And Mn ²⁺, and Mn ²⁺Stripping causes.

The method of dealing with problems

The present invention relates to reduce the negative pole polarization in the lithium primary battery, especially when low-temperature high-current discharge or after high temperature storage, reduce the negative pole polarization.Based on the present invention, can improve heavy-current discharge performance under the lithium primary battery low temperature and the storage characteristics under the high temperature and can not sacrifice the others of battery performance and reliability.

Lithium primary battery of the present invention comprises: the barrier film between positive pole, negative pole, organic bath and insertion positive pole and negative pole; Described negative pole comprises negative active core-shell material, and described negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy.

Below negative pole has in (a)-(c) feature any one.

(a) the skin section branch of negative pole comprises the compound of amorphous carbon cellulosic material and negative active core-shell material at least, and described top layer part is inserted with barrier film in the face of anodal between them.

(b) at the desired depth place of distance facing to the negative pole in the negative terminal surface 5nm-15nm scope of positive pole, there are halogen atom, lithium atom and oxygen atom, and the mol ratio X/Li of halogen atom and lithium atom is 0.7 or lower, and halogen atom and with the mol ratio X/O of oxygen atom be 1.3 or lower.Equally in the case, the top layer part of negative pole preferably comprises the compound of amorphous carbon cellulosic material and negative active core-shell material at least, and the top layer part is inserted with barrier film in the face of anodal between them.

(c) negative pole comprises the top layer part of embedding particulate; It is 2 μ m or littler primary granule that described particulate comprises average grain diameter (meta particle diameter); And the top layer part is inserted with barrier film in the face of anodal between them.

When negative pole had the feature of above-mentioned (a), negative pole can be a sandwich construction, and it comprises: comprise the top layer part of compound of amorphous carbon cellulosic material and negative active core-shell material and the underclad portion that comprises negative active core-shell material.In the case, the thickness on top layer be preferably negative pole thickness 1/3 or littler.

When negative pole had the feature of above-mentioned (b), halogen atom came from the anionic decomposition of the solute that comprises in the organic bath or comes from the impurity (HF etc.) of solute.When using fluorine-containing solute (LiBF for example ₄) time, lithium fluoride (LiF) is present in apart from the negative pole desired depth place that faces in the anodal negative terminal surface 5nm-15nm scope.When using chloride solute (as lithium perchlorate), there is lithium chloride (LiCl).There is thin oxidation film at the lithium metallic surface.When making battery pre-arcing after assembling, oxidation film is destroyed.After this, lithium and organic electrolysis qualitative response form new film.At this moment, halogen atom is incorporated in the negative pole.The nonaqueous solvents that oxygen source comprises in organic bath.Oxygen for example forms lithium carbonate Li ₂CO ₃Think LiF and Li ₂CO ₃In organic bath, play a part the negative pole diaphragm.

Lithium ion is at Li ₂CO ₃Middle than easier diffusion in LiF.When having a large amount of lithium fluoride (LiF) in the part of negative pole top layer, be not easy to cause the migration of lithium ion to negative pole.Therefore, think and increased reaction resistance (overvoltage).Therefore, by suppressing the generation of lithium halide such as lithium fluoride, can reduce the polarization of negative pole.

For the analytical method apart from the composition of facing the negative pole desired depth place in the anodal negative terminal surface 5nm-15nm scope, it is the most frequently used method that the x-ray photoelectron spectroscopy method is analyzed (XPS).In XPS, can determine the amount (NA) of the elements A of existence from following formula.

NA=(peak area of elements A) * (correlation factor of elements A)

Correlation factor depends on measurement mechanism.By measuring the amount of all elements that exists, can calculate the mol ratio of element.Usually, by the automatic computing function of analytical equipment, the amount of the element that can obtain to exist and mol ratio.

In being attached with the negative pole of organic bath, promptly use lower boiling solvent wash also to be difficult to remove fully organic substance.Therefore, the analysis result on the outmost surface is influenced by the very big of attachment material.Therefore, generally after carrying out etching, carry out XPS analysis with argon ion sputtering.By using SiO ₂Sample is accurately measured the etch-rate with argon ion sputtering.Usually, also in other sample, use SiO ₂The etch-rate of sample.For example, when measurement mechanism is by Physical Electronics, 5600 types of Inc. preparation, and when carrying out argon ion sputtering under the accelerating voltage of 3kV, etch-rate is 7.4nm/min.To regard outmost surface (the 0nm degree of depth) as in the face of anodal negative terminal surface before the etching, and analyze the composition at desired depth place in the scope of outmost surface 5nm-15nm.

When negative pole comprised amorphous carbon, in whole negative pole, the content of amorphous carbon cellulosic material in negative active core-shell material and amorphous carbon cellulosic material total amount was preferably 5wt% or lower.In the part of top layer, the content of amorphous carbon cellulosic material in negative active core-shell material and amorphous carbon cellulosic material total amount is preferably 5wt% or lower equally.

The amorphous carbon cellulosic material preferably comprises the particulate that average grain diameter (meta particle diameter) is 0.1 μ m or littler primary granule.In addition, the amorphous carbon cellulosic material is 20m by the BET specific area of nitrogen adsorption measurement for example preferably ²/ g or bigger particulate.For the amorphous carbon cellulosic material, for example preferred use be selected from acetylene black, Ketjen black, contact black, furnace black and dim at least a carbon black.

When negative pole has the feature of above-mentioned (c), can use pottery, lithium compound and carbon materials for particulate.Can be separately or with two or more these materials that is used in combination.

For pottery, can use Al ₂O ₃, Fe ₂O ₃, SiC, SiO ₂, ZrO ₂Can be separately or with two or more these materials that is used in combination.These potteries have the hardness that can easily be pressed in lithium or the lithium alloy surface.In addition, these potteries and lithium is reactive low.

For lithium compound, can use Li ₃PO ₄And Li ₂SO ₄Can be separately or with two or more these materials that is used in combination.

For carbon materials, can use graphite, petroleum coke and active carbon.Can be separately or with two or more these materials that is used in combination.When using graphite particulate, in the top layer of embedding particulate part, the reaction in the lithium insertion graphite linings takes place.By this reaction, produce red or golden lithium-graphite intercalation compound.

As particularly preferred particulate, can mention following particulate.

(i) comprise the carbon granule that average grain diameter (meta particle diameter) is 0.1 μ m or littler primary granule.

(ii) the BET specific area of being measured by the nitrogen adsorption method is 20m ²/ g or bigger carbon granule.

(iii) be selected from acetylene black, Ketjen black, contact black, furnace black and dim at least a carbon black.Equally, in these carbon blacks, primary granule preferably has 0.1 μ m or littler average grain diameter (meta particle diameter) and the 20m that is measured by the nitrogen adsorption method ²/ g or bigger BET specific area.

Top carbon granule (i)-has (iii) suppressed the increase of the internal resistance of cell.Therefore, the negative pole polarization in the time of can reducing discharge effectively.

The lithium alloy that can be included in the negative active core-shell material for example comprises a spot of aluminium (Al) and tin (Sn).In the situation of lithium alloy, can expect to compare performance and surface condition has improvement with the lithium metal.But, in the situation of alloy, to compare with lithium, the increase of fusing point and hardness may cause the reduction of machinability.Therefore, the metal beyond the lithium that comprises in the lithium alloy is preferably a spot of.Metal preference beyond the lithium is as being the 5wt% of whole alloy or lower.

Positive pole comprises positive electrode active materials, electric conducting material and binding agent.Positive electrode active materials preferably includes metal oxide or fluorographite.The present invention is especially effective when using fluorographite.For metal oxide, can mention manganese dioxide as positive electrode active materials.Although anodal preparation method is not particularly limited, for example can hybrid packet containing metal oxide or positive electrode active materials, electric conducting material and the binding agent of fluorographite use.

For organic bath, can use the nonaqueous solvents that has dissolved solute.Solute preferably includes LiBF4.Nonaqueous solvents preferably includes gamma-butyrolacton.

The invention still further relates to the preparation method of lithium primary battery, described method comprises step:

The preparation negative pole, described negative pole comprises the compound of negative active core-shell material and amorphous carbon cellulosic material at least at its skin section branch, and negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy; And

Make the top layer part that comprises described compound in the face of anodal, be inserted with barrier film between them.

The preparation negative pole, described negative pole comprises the compound of negative active core-shell material and particulate at least at its skin section branch, and described negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy; And it is 2 μ m or littler primary granule that described particulate comprises average grain diameter (meta particle diameter); And

For the preparation process of negative pole that comprises the compound of negative active core-shell material and amorphous carbon cellulosic material at least at the skin section branch of negative pole, for example can mention following step.

The first, can mention the mixture that preparation comprises amorphous carbon cellulosic material and negative active core-shell material, and described mixture be formed the step of the negative pole of predetermined form.

The second, can mention preparation and comprise the mixture of amorphous carbon cellulosic material and negative active core-shell material, roll described mixture and form thin slice, and gained mixture sheet is attached to step on described negative active core-shell material (for example lithium metal) sheet by pressure.

The 3rd, can mention the paste that preparation comprises amorphous carbon cellulosic material, binding agent and organic solvent; Described paste coating is to negative active core-shell material (for example lithium metal) sheet, dry then; And roll the step of described film and sheet simultaneously.

The 4th, can mention on negative active core-shell material (for example lithium metal) surface spraying amorphous carbon cellulosic material, and roll described amorphous carbon cellulosic material and described step simultaneously.Before calendering, can the negative electrode active material tablet be heated to 100-200 ℃ with heating plate, make the amorphous carbon cellulosic material to be attached to easily on described.

Preferably in argon gas atmosphere or under 100Pa or lower reduced atmosphere, carry out comprising at its skin section branch at least the preparation process of the negative pole of amorphous carbon cellulosic material.Carbon black is the particulate with big BET specific area.Therefore, carbon black is extremely inflammable, a large amount of oxygen of its absorption, and as oxidant.Therefore, when making it in dry air (50 ℃ or lower dew point) contact lithium metal, promptly during strong reductant, oxidation-reduction reaction may carry out fast.In addition, when making carbon black in the nitrogen atmosphere of doing during with the lithium Metal Contact, lithium and nitrogen reaction produce lithium nitride.

At least the skin section branch of negative pole comprise negative active core-shell material and particulate compound negative pole for example can by simply on the part of described negative pole top layer embedding to comprise average grain diameter be that the particulate of 2 μ m or littler primary granule obtains.For instance, by pressure particulate is attached on the negative terminal surface or with particulate and is pressed onto on the negative terminal surface, particulate can be embedded into negative pole top layer part.

Effect of the present invention

Based on the present invention, the increase of the internal resistance of cell in the low temperature range can be suppressed at, and the reaction overvoltage of negative pole can be reduced, cause the improvement of heavy-current discharge performance under the low temperature.In addition, the increase of the internal resistance of cell in the time of can suppressing high temperature storage.In addition, even when the battery after the discharge of storage area at high temperature, also can improve the discharge performance after the storage.Therefore, based on the present invention, can provide the reliable lithium primary battery of heavy-current discharge performance and high-temperature storage performance aspect excellence under the low temperature.

Based on the present invention, can increase exoelectrical reaction active site, can reduce the negative reaction overvoltage and can improve low temperature performance.In addition, based on the present invention, the high-temperature stability of lithium primary battery and long-term reliability can not lose too big.Because the present invention relates to primary cell, so not supposition charging reaction.Therefore, the effect performance deficiency that suppresses the negative pole polarization of discharge initial stage.

Below, illustrate how to have given play to effect of the present invention.

The exoelectrical reaction of lithium primary battery be lithium ion from the negative pole stripping, and lithium ion inserts the reaction in the positive electrode active materials.Exoelectrical reaction relates to the resistance of anodal and negative pole, in the electrolyte of impregnated electrode and barrier film the resistance of ion transfer and positive pole and negative pole is moved the reaction resistance that electric charge relates to.The overvoltage that these resistance elements cause is because condition, for example electrode structure, battery structure, discharge temp and discharge current density and change.In being higher than 0 ℃ high temperature range, the negative pole overvoltage is less than anodal overvoltage.But in 0 ℃ or following low temperature range, the negative pole overvoltage increases fast, and the condition that depends on surpasses anodal overvoltage sometimes.

In discharge, think that from the reaction of negative pole stripping lithium ion be to be caused by crystal boundary lithium metal and the lithium alloy and crystal defect.Form crystal defect when when extrusion process lithium metal and lithium alloy or to them, rolling.There is the film that comprises lithium oxide etc. on the surface of lithium metal and lithium alloy.In organic bath, there is the film comprise mainly the electrolyte reduction decomposition product of forming by lithium carbonate.These films still also can suppress the stripping reaction of lithium ion as suppressing the diaphragm that electrolyte decomposes.

By after lithium primary battery assembling immediately to battery pre-arcing, think and destroyed the film that on lithium metal and lithium alloy surface, forms before the assembling.Therefore, the reaction resistance of negative pole depends primarily on the film that comprises the organic bath catabolite.

When negative pole skin section branch comprises the amorphous carbon cellulosic material, and then after the battery assembling, insert in the amorphous carbon cellulosic material at the lithium ion at the interface of negative pole and organic bath temporarily, and carry out electrolytical decomposition reaction.As a result, at negative pole and electrolytically will form the electrolyte catabolite in a short time at the interface.Described catabolite is as suppressing the diaphragm that continuous electrolysis matter is decomposed.The film that forms during with lithium alloy with independent use lithium metal is compared, and this diaphragm is stable, and has suppressed because electrolyte after this decomposes the increase of the internal resistance of cell that causes.

Negative reaction resistance height depends on temperature, and (especially 0 ℃ or following) increase suddenly in low temperature range usually.But, as mentioned above, because suppressed the increase of the internal resistance of cell, so even in low temperature range, also suppressed the superpotential unexpected increase of negative pole.Similarly, when high temperature storage, also suppress the increase of the internal resistance of cell, and greatly reduced the negative pole polarization at storage back discharge initial stage.In addition, even when the battery after the storage area discharge at high temperature, also can obtain to suppress the effect that internal resistance increases.When this effect when all there is the amorphous carbon cellulosic material in negative pole inside is especially big.

In addition, comprise the particulate that average grain diameter is 2 μ m or littler primary granule, in the crystal of lithium metal and lithium alloy, form new defective by divide embedding in the negative pole skin section.Therefore, from the reactivity point increase of negative pole stripping lithium ion, and the reaction overvoltage of negative pole reduces.

When using graphite, form lithium-graphite intercalation compound as particulate.Similar to the negative material of lithium rechargeable battery, lithium-graphite intercalation compound causes the stripping reaction of lithium ion.Therefore, when discharge, not only can use lithium ion stripping reaction, and can use lithium ion stripping reaction from intercalation compound from lithium metal and lithium alloy.Therefore, can further reduce the reaction overvoltage of negative pole.

For particulate, use (i) to comprise the carbon granule that average grain diameter (meta particle diameter) is 0.1 μ m or littler primary granule effectively; (ii) the BET specific area of being measured by the nitrogen adsorption method is 20m ²/ g or bigger carbon granule; Perhaps (iii) be selected from acetylene black, Ketjen black, contact black, furnace black and dim at least a carbon black.When using these particulates,, can see the effect that the internal resistance of cell increases that suppresses although reason it be unclear that now.For this reason, suppose following effect.

When using the solvent (for example propylene carbonate and gamma-butyrolacton) of the organic bath in primary cell, use in as the lithium rechargeable battery of negative active core-shell material with general carbon materials, the known solvolysis reaction that in battery, produces.Same in being embedded in negative pole top layer part carbon granule and electrolyte between at the interface, think to produce similar decomposition reaction.This catabolite has suppressed the electrolyte decomposition reaction at lithium/electrolyte interface place, and thinks the increase that has suppressed the internal resistance of cell after this.

Description of drawings

[Fig. 1] is according to the vertical sectional view of coin type lithium primary battery of the present invention.

[Fig. 2] expression is apart from the figure in the face of concerning between the negative pole degree of depth of anodal negative terminal surface and the mol ratio F/Li by the fluorine atom of XPS detection and lithium atom.

[Fig. 3] expression is apart from the figure in the face of concerning between the negative pole degree of depth of anodal negative terminal surface and the mol ratio F/O by the fluorine atom of XPS detection and oxygen atom.

The schematic sectional view of an example of [Fig. 4] negative pole of the present invention.

The schematic sectional view of another example of [Fig. 5] negative pole of the present invention.

Embodiment

Lithium primary battery of the present invention comprise positive pole, negative pole, organic bath and be inserted in described positive pole and described negative pole between barrier film.The form or the structure of battery are not particularly limited, and comprise for example column type, prismatic, button type and coin type.Lithium primary battery of the present invention relates generally to the improvement of negative pole, and is not particularly limited for the The Nomenclature Composition and Structure of Complexes of positive pole, organic bath and barrier film.

Negative pole comprises negative active core-shell material, and negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy.

Negative pole has in following (a)-(c) feature.

(a) the skin section branch of negative pole comprises the compound of amorphous carbon cellulosic material and negative active core-shell material at least, and described top layer part is inserted with barrier film in the face of anodal between them.Except amorphous carbon cellulosic material and negative active core-shell material, the top layer part of negative pole can also comprise the carbon materials beyond unavoidable impurities and the amorphous carbon.

(b) apart from facing to the negative pole desired depth place in the scope of the negative terminal surface 5nm-15nm of positive pole, have halogen atom, lithium atom and oxygen atom: the mol ratio of halogen atom and lithium atom is that X/Li is 0.7 or lower, and the mol ratio of halogen atom and oxygen atom is that X/O is 1.3 or lower.Equally in the case, the skin section branch of negative pole comprises the compound of amorphous carbon cellulosic material and negative active core-shell material at least, and the top layer part is inserted with barrier film in the face of anodal between them.

(c) the negative pole top layer part of particulate that comprised embedding; The average grain diameter of the primary granule of particulate (meta particle diameter) is 2 μ m or littler; And the top layer part has barrier film in the face of anodal between them.Except particulate and negative active core-shell material, the top layer part of negative pole can comprise draws together unavoidable impurities.

The lithium metal is the lithium simple substance that is generally metallic state, and can comprise trace impurity.Lithium alloy comprises the metal beyond the lithium, for example a spot of aluminium (Al), tin (Sn), magnesium (Mg), indium (In) and calcium (Ca).The content preference of the metal beyond the lithium that comprises in the lithium alloy is as being the 5wt% of whole alloy or lower, and more preferably 1wt% or lower.Can use the combination of lithium metal and lithium alloy to form negative pole.

Can change the composition of negative active core-shell material by the part negative pole.For example, lithium simple substance can be used for the top layer part of negative pole, and lithium alloy can be used for underclad portion.For underclad portion, for example preferred lithium alloy that comprises 0.2wt% aluminium that uses.

Have above-mentioned feature (a) or negative pole (b) and can or comprise negative active core-shell material and the mould of the mixture of amorphous carbon prepares from the mould of negative active core-shell material.The mixture that comprises negative active core-shell material and amorphous carbon comprises: comprise the mixture of lithium metal and amorphous carbon, the mixture that comprises the mixture of lithium alloy and amorphous carbon and comprise lithium metal, lithium alloy and amorphous carbon.For example, can prepare negative pole from lithium metal or the lithium alloy that is configured as sheet or electrode form.In addition, can prepare negative pole from the mixture that comprises negative active core-shell material and amorphous carbon of making sheet or electrode form.In that lithium metal or lithium alloy is molded when in blocks, push or roll.Negative pole can comprise or not comprise the collector that contains lithium metal foil and net.

Although negative pole can be fully formed by the compound of amorphous carbon cellulosic material and negative active core-shell material, in the part beyond the part of top layer, not necessarily comprise the amorphous carbon cellulosic material.The boundary that comprises the top layer part of compound and do not comprise between the underclad portion of amorphous carbon cellulosic material can become clear, perhaps can change the amount of amorphous carbon cellulosic material in the thickness direction of negative pole gradually.For example, a large amount of amorphous carbon cellulosic material that can distribute in the outmost surface of top layer part, and can be towards the negative pole inboard with the distribution of gradient reduction amorphous carbon cellulosic material.

In whole negative pole, the content of amorphous carbon cellulosic material in negative active core-shell material and amorphous carbon cellulosic material total amount is preferably 5wt% or lower, and more preferably 0.02wt% or higher and 2wt% or lower.The amorphous carbon cellulosic material content of this degree has obtained the effect at interface between stable negative pole and electrolyte, and can not reduce the energy density of negative pole.

In the top layer part of the compound that comprises negative active core-shell material and amorphous carbon cellulosic material and do not comprise between the underclad portion of amorphous carbon cellulosic material and can recognize in the situation of boundary, the thickness of top layer part be preferably negative pole thickness 1/3 or lower, and more preferably 1/5 or higher, 1/20 or lower.In addition, in the part of top layer, promptly the content of amorphous carbon cellulosic material is preferably 5wt% or lower in the compound, and more preferably 0.02wt% or higher and 2wt% or lower.Even negative pole thickness 1/3 or lower top layer segment thickness also are enough to control the interface between negative pole and electrolyte.Do thinly by the top layer part that will comprise compound, suppressed excessive electrolyte decomposition reaction.Particularly, preferably do the top layer part thin for the discharge under the weak current.When fluorographite was used for positive pole, especially, it was significant that the just interim voltage of discharge reduces, and discharge voltage carries out along with discharge and increases.Therefore, the top layer part that will comprise compound is done the thin performance at discharge initial stage of improving effectively.

Apart from desired depth place, preferably there are halogen atom, lithium atom and oxygen atom in the face of the negative pole in the anodal negative terminal surface 5nm-15nm scope.When by XPS when this depth survey is formed, the mol ratio of halogen atom and lithium atom, promptly X/Li is preferably 0.7 or lower.The mol ratio of halogen atom and oxygen atom, promptly X/O is preferably 1.3 or lower.In the case, can obtain the effect at interface between stabilize lithium and electrolyte.

Angle near the even distribution amorphous carbon cellulosic material active part on lithium surface, it is 0.1 μ m or littler that the amorphous carbon cellulosic material preferably comprises average grain diameter (meta particle diameter), and the more preferably particulate of 0.03 μ m or bigger and 0.1 μ m or littler primary granule.In addition, from permission and electrolyte solvent rapid-action angle, the BET specific area that the amorphous carbon cellulosic material is preferably for example measured by nitrogen adsorption is 20m ²/ g or bigger, and more preferably 50m ²/ g or bigger and 100m ²/ g or littler particulate.In addition, preferably its at least 50% or more surface on cover the amorphous carbon cellulosic material with carbon materials.That is, the area to the negative terminal surface of positive pole is defined as S face to face, and the area of the negative terminal surface that covers with carbon materials is defined as Sc, and coverage rate is when being defined as Rs=(Sc/S) * 100 (%), and Rs is preferably 50% or bigger.

By cover with carbon materials 50% or more in the face of anodal negative terminal surface (by the control coverage rate be 50% or bigger (preferred 50-90%)), can control the condition at the interface between negative pole and electrolyte well.For example, by use the visual field can sightingpiston to the microscope of the whole negative terminal surface of positive pole, can measure coverage rate Rs.In the image with the surface of microscopic examination or shooting, the area that hides with carbon materials is exactly a coverage rate with respect to the ratio in the face of the area of anodal negative pole.In the direction vertical, observe or take surface image with facing anodal negative terminal surface.

The amorphous carbon cellulosic material comprises carbon black, active carbon, coke and glassy carbon (vitreous carbon).Can be separately or be used in combination the amorphous carbon cellulosic material with two or more.Wherein, because obtain microgranular easily and material high-specific surface area, so carbon black is preferred especially.For carbon black, can use acetylene black, Ketjen black, contact black, furnace black and dim.Can be separately or with two or more these carbon blacks that is used in combination.Because carbon black is a particulate,, its primary granule generates secondary granule so may condensing.Preferably use 150 ℃-250 ℃ heated-air drying carbon black, perhaps drying under reduced pressure uses carbon black after with the water of removing volatile component and absorption.

Hereinafter, shown negative pole preparation method's a example, described negative pole comprises:

At least top layer part, described skin section branch comprises the compound of negative active core-shell material and amorphous carbon cellulosic material, and described negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy.

The first, the step that can mention is the mixture that preparation comprises amorphous carbon cellulosic material and negative active core-shell material, and described mixture is molded as the step of the negative pole of predetermined form.When the compound from amorphous carbon cellulosic material and negative active core-shell material forms whole or basically during whole negative pole, this method is suitable.

The second, the step that can mention is that preparation comprises the mixture of amorphous carbon cellulosic material and negative active core-shell material, rolls described mixture forming thin slice, and by pressure gained mixture sheet is attached to step on lithium metal or the lithium alloy sheet.Can be by with the sheet cutting of the crimping of gained or strike out desired form and obtain negative plate.When forming two-layer negative plate, described negative plate comprises top layer part and underclad portion, and described skin section branch comprises the compound of amorphous carbon cellulosic material and negative active core-shell material, and described underclad portion is when comprising negative active core-shell material, and this method is suitable.

The 3rd, the step that can mention is the paste that preparation comprises amorphous carbon cellulosic material, binding agent and organic solvent; Described paste coating is on lithium metal or lithium alloy sheet, dry then; And roll the step of described film and sheet simultaneously.When forming two-layer negative plate, described negative plate comprises top layer part and underclad portion, described skin section branch comprises the compound of amorphous carbon cellulosic material and negative active core-shell material and forms, and described underclad portion is when comprising negative active core-shell material, and this method is suitable.

The 4th, the step that can mention is a spraying amorphous carbon cellulosic material on lithium metal or lithium alloy sheet surface, rolls the amorphous carbon cellulosic material that sprayed and described step then simultaneously.By heating lithium metal or lithium alloy sheet before calendering, form the top layer part of the compound that comprises amorphous carbon cellulosic material and negative active core-shell material easily.Suitable heating-up temperature is 100-200 ℃.When the top layer of the compound that comprises amorphous carbon cellulosic material and negative active core-shell material part will form thinly, this method was suitable.

Preferably in argon gas atmosphere or under 100Pa or lower decompression, implement aforesaid negative pole preparation process.Can also in the rare gas atmosphere beyond the argon gas, implement these steps.This atmosphere prevents from oxidation-reduction reaction to take place between carbon black and lithium metal and prevent to produce lithium nitride.

Provide preparation method's the example of the negative pole of coin type battery in detail.In the argon gas glove box, on the lithium sheet metal, spray carbon black, and be heated to about 200 ℃ with described with heating plate.At this moment, the lithium with fusion floods carbon black to form the compound of carbon black and lithium.In addition, carbon black can be clipped between a pair of lithium sheet metal, and be heated to about 200 ℃.Preferably under 100Pa or lower decompression, heat, thereby quicken to flood carbon black with molten lithium.In addition, prepare molten mixture, and in inert atmosphere, they are stirred and quicken even mixing by heating lithium sheet and hydrocarbon black powder.

Then, use the small-sized rolling device that is placed in the inert atmosphere,, and do the thickness of sheet evenly the compound tablet forming of lithium and carbon black.When the thickness of lithium metal is little, 100 μ m or more hour for example can spray the sheet of carbon black and accompany the sheet of carbon black and need not pass through heat fused with the rolling device calendering.Sheet by having predetermined thickness with die cut can obtain negative pole when obtaining predetermined form.The gained negative pole is crimped onto the inboard of battery case.

For example, by with lithium metal or the molded form in blocks of lithium alloy or the form of electrode,, can obtain to have the negative pole of above-mentioned feature (c) then to the surface adhesion of gained sheet or molding or be pressed into particulate.With the molded form in blocks of lithium metal or lithium alloy the time, for example push and roll.Negative pole can comprise or not comprise the collector that contains metal forming or net.

From easily particulate being embedded into the angle on lithium metal surface or lithium alloy surface, particulate preferably has than lithium and the higher hardness of lithia.But if particulate can be pressed in lithium metal or the lithium alloy by the top layer of disruptive oxidation lithium, hardness is enough so.For particulate, for example can use pottery, lithium compound and carbon materials.Can be separately or with two or more these materials that is used in combination.

For pottery, can use Al ₂O ₃, Fe ₂O ₃, SiC, SiO ₂And ZrO ₂Can be separately or with two or more these potteries that is used in combination.These potteries have the hardness that is enough to easily be pressed in lithium or the lithium alloy surface, and reactive low with lithium.In addition, these potteries are stable in lithium battery, and obtain the pottery that those have suitable particle diameter easily.

For lithium compound, can use Li ₃PO ₄And Li ₂SO ₄Can be separately or with two or more these materials that is used in combination.These lithium compounds are stable but preferred because of it to lithium and organic bath.

For carbon materials, can use graphite, petroleum coke and active carbon.Can be separately or with two or more these materials that is used in combination.When forming the carbon materials of tangible intercalation compound with lithium, when for example graphite was embedded in the lithium surface, graphite granule reddened in several hours.When making these graphite granules in dry air atmosphere, leave standstill about 12 hours, on the lithium surface, form golden to red intercalation compound.Although in the situation of coke, active carbon and carbon black, can not observe this clearly variation, the reaction with lithium similarly may take place.When exoelectrical reaction, the lithium that reacts with carbon materials takes off slotting from carbon materials.Therefore, when using carbon materials, except the embedding owing to carbon materials causes that the lithium stripping quantity increases, can use the lithium desorption reaction as particulate.As a result, reducing the superpotential effect of reaction increases.

In carbon materials, when the carbon materials below using, can also obtain to suppress the effect of internal resistance of cell increase: the carbon granule that (i) comprises average grain diameter (meta particle diameter) and be 0.1 μ m or littler primary granule; (ii) the BET specific area of being measured by the nitrogen adsorption method is 20m ²/ g or bigger carbon granule; And (iii) be selected from acetylene black, Ketjen black, contact black, furnace black and dim at least a carbon black.Because the carbon materials that is fixed on the lithium has identical electromotive force with lithium, so can suppress the increase of internal resistance.That is, when the carbon materials on being fixed to lithium contacts electrolyte, the insertion of lithium ion and the decomposition reaction of solvent take place immediately, and the lithium surface coverage there is electrolytical catabolite.This catabolite is as the protective layer that suppresses the electrolyte decomposition reaction at lithium/electrolyte interface place.Therefore, suppressed the increase of the internal resistance of cell then.Especially under low temperature environment, suppressed the increase of the internal resistance of cell greatly.As a result, the improved action to voltage drop under the heavy-current discharge becomes remarkable.

Although be added to kind and negative pole form that the amount of the particulate of negative pole top layer part depends on particulate, therefore can not vague generalization and be not particularly limited, the amount that is added to the particulate of negative pole top layer part is preferably per unit surface area, i.e. m for instance ², 0.1-50g.The particulate loading of this degree can not reduce the energy density of negative pole greatly, and can not influence discharge performance greatly by the resistance that particulate causes.

In the present invention, the average grain diameter of the primary granule of particulate (meta particle diameter) is 2 μ m or littler, and 0.5 μ m or littler more preferably, makes that the ratio of the negative terminal surface of embedding particulate (in the face of anodal surface) does not diminish.When the average grain diameter of particulate surpassed 2 μ m, the ratio of the negative terminal surface of embedding particulate did not become big, can not realize suppressing at the discharge initial stage fully the effect of polarization.

The maximum particle diameter of particulate is preferably 5 μ m or littler.When being mixed into particle diameter and being 5 μ m or bigger bulky grain, be difficult to by being squeezed near the adhesion of particles particle with this size, and may cause that the ratio of the negative terminal surface of embedding particulate becomes big.Therefore, particulate preferably has 2 μ m or littler average grain diameter, and has narrow as far as possible particle size distribution.From above, the carbon black with primary granule of 0.1 μ m or littler average grain diameter (meta particle diameter) is preferred for particulate.Preferably after with 150 ℃-250 ℃ heated-air drying, perhaps drying under reduced pressure uses carbon black after with the water of removing volatile component and absorption.

Although preferably particulate is embedded into the top layer part of negative pole,, for example also can use secondary granule in the situation of carbon black at the particulate of the cohesion formation secondary granule by primary granule easily with the state of primary granule.

Hereinafter, preparation method's a embodiment who has shown the negative pole of coin type battery.

When comprising the water of volatile component and absorption in the particulate, at first remove them.More particularly, with the heated-air drying particulate of 100 ℃-200 ℃ (in the situations of carbon black 150 ℃-250 ℃), perhaps drying under reduced pressure particulate.Then, paint particles on lithium metal or lithium alloy sheet surface.Then, the weak pressure calendared sheet by with the original thickness that can not change sheet is inserted with for example processing release paper of polyethylene film therebetween, particulate is embedded into the top layer part of sheet.Then, peel off processing release paper to remove the particulate that is not embedded into sheet top layer part.By with punch die with skin section divide embedding the sheet punching press of particulate to obtain preliminary dimension, obtained required negative pole.The negative pole of gained is connected to the inboard of coin type battery case by pressure.

Top method only is an example, and can prepare negative pole with other many methods.For example, can will be scheduled to the lithium metal of form or the inboard that lithium alloy is connected to battery case in advance, and the particulate that the spraying drying is crossed on lithium metal or lithium alloy surface then comes the embedding particulate by pressure.Perhaps, can disperse the dry particulate of crossing to prepare dispersion in the 2-dimethoxy-ethane by at solvent propylene carbonate and 1 for example.This dispersion is coated to film for example on the polyester film and dry, transfers to the surface of lithium metal or lithium alloy sheet then.

Preferably in argon gas atmosphere or in 100Pa or lower reduced atmosphere, implement aforesaid negative pole preparation process.Can also in the rare gas atmosphere beyond the argon gas, implement described step.This is because in these atmosphere, the generation that can prevent that oxidation-reduction reaction takes place between particulate and the lithium and prevent lithium nitride.

Although be not particularly limited for positive pole, positive pole comprises positive electrode active materials, electric conducting material and binding agent for instance.The present invention improves the discharge performance at discharge initial stage by suppressing the negative pole overvoltage, therefore is not particularly limited positive electrode active materials.

For positive electrode active materials, for example can use metal oxide and fluorographite.Can be used in combination metal oxide and fluorographite.The lithium metal oxide that is used for positive electrode active materials comprises manganese dioxide and Cu oxide.For fluorographite, can preferably use by chemical formula CF _xThe fluorographite of (0.8≤x≤＜1.1) representative.Fluorographite is being excellent aspect long-term reliability, fail safe and the high-temperature stability.By being fluoridized, petroleum coke and Delanium obtain fluorographite.

For the electric conducting material of positive pole, for example can use for example acetylene black and Ketjen black and graphite Delanium for example of carbon black.Can be separately or with two or more these materials that is used in combination.

For anodal binding agent, for example can use fluorocarbon resin, for example polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), the PVDF of modification, tetrafluoraoethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), vinylidene difluoride-hexafluoropropylene copolymer, vinylidene fluoride-chlorotrifluoroethylene, ethylene-tetrafluoroethylene copolymer (ETFE resin), vinylidene fluoride-five fluorine propylene copolymer, propylene-TFE copolymer, ethylene-chlorotrifluoro-ethylene copolymer (ECTFE), and vinylidene fluoride-hexafluoropropylene-TFE copolymer; Styrene butadiene rubbers (SBR); The acrylic-nitrile rubber of modification; And ethylene-acrylic acid copolymer.Can be separately or with two or more these materials that is used in combination.

For organic bath, can use the nonaqueous solvents of dissolving solute.Vinylene carbonate, vinylethylene carbonate, sulfurous acid second diester and the dimethyl sulfone that can add a few percent in electrolyte are as additive.

For solute, can use lithium hexafluoro phosphate (LiPF ₆), LiBF4 (LiBF ₄), trifluoromethayl sulfonic acid lithium (LiCF ₃SO ₃) and two pentafluoroethyl group sulfimide lithium (LiN (SO ₂C ₂F ₅) ₂).Can be separately or with two or more these materials that is used in combination.

For nonaqueous solvents, can use cyclic carbonate, for example gamma-butyrolacton (γ BL), gamma-valerolactone (γ VL), propylene carbonate (PC) and ethylene carbonate (EC); 1,2-dimethoxy-ethane (DME), 1,2-diethoxyethane (DEE), 1, the 3-dioxolanes, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethylene methyl esters (EMC), N, dinethylformamide, oxolane, the 2-methyltetrahydrofuran, methyl-sulfoxide, formamide, acetamide, dimethyl formamide, dioxolanes, acetonitrile, propionitrile, nitromethane, ethyl Monoethylene Glycol (MEG) dimethyl ether (ethylmonoglyme), trimethoxy-methane, dioxolane derivatives, sulfolane, methyl sulfolane, polypropylene carbonate ester derivant and tetrahydrofuran derivatives.Can be separately or with two or more these materials that is used in combination.Wherein, (γ-BL) is stable in wide temperature range and dissolves solute easily, so it is especially preferred because gamma-butyrolacton.But, from improving the angle of the ionic conductance under the low temperature, preferably making low boiling point solvent 1,2-dimethoxy-ethane (DME) mixes with γ-BL and uses them.In addition, when nonaqueous solvents comprises γ-BL, preferably use LiBF ₄As solute.When being used in combination gamma-butyrolacton and other solvent, the ratio of the whole relatively nonaqueous solvents of gamma-butyrolacton is preferably 50wt% or bigger.

Diaphragm material can be the material of opposing lithium primary battery internal environment, for example the microporous barrier of the nonwoven fabrics of the nonwoven fabrics of polypropylene system, polyphenylene sulfide system and vistanex (polyethylene and polypropylene etc.) system.

Hereinafter, describe the present invention in detail based on embodiment, but the following examples the present invention without limits.

In embodiment and Comparative Examples, preparation coin type battery 10 as shown in Figure 1.Coin type battery 10 comprise disc positive pole 4, disc negative pole 5 and be inserted in anodal 4 and negative pole 5 between polypropylene non-woven fabric barrier film 6.Be placed on the inner bottom surface of stainless steel anode cover 1 anodal 4.Negative pole 5 is crimped onto the inner surface of stainless steel negative electrode casing 2.Peripheral part attaching polypropylene insulation filler 3 to negative electrode casing 2.By to the on every side end crimping of insulating packing 3, seal the space that holds positive pole 4, negative pole 5, barrier film 6 and organic bath (not shown) with anode cover 1.Positive pole 4 and negative pole 5 are arranged to face with each other, are inserted with barrier film 6 between them.

Embodiment 1A

(i) Zheng Ji preparation

For positive electrode active materials, petroleum coke fluoridized and as fluorographite.With 100: 15: 6 solids content weight ratio mixed fluoride graphite, acetylene black (electric conducting material) and styrene butadiene rubbers (SBR) (binding agent), and the mixed solution of water and ethanol is fully mediated them as decentralized medium.Behind 100 ℃ of dry gained mixtures, come compression molded described mixture to obtain the disk shape by using predetermined mould and hydraulic press, thereby obtain anodal.

The (ii) preparation of negative pole

Use the lithium metal as negative active core-shell material, and use the acetylene black (AB) for preparing by Denki Kagaku KogyoKabushiki Kaisha as the amorphous carbon cellulosic material.The average grain diameter of the primary granule of acetylene black is 0.04 μ m, and the BET specific area is 60m ²/ g.Under reduced pressure, be introduced into then in the predetermined negative pole prepared atmosphere in 120 ℃ of dry acetylene blacks.Equally in other embodiment and Comparative Examples, under reduced pressure dry amorphous carbon materials similarly is introduced in the negative pole prepared atmosphere then.

Cut the thick lithium sheet metal of 150 μ m and obtain suitable length, and section is placed on the container of stainless steel, put into argon gas glove box (negative pole prepared atmosphere) then.The acetylene black that drying is crossed sprays in the section of lithium metal.Then, the container that is placed with the section of lithium metal is put on the heating plate, and heats 1 hour with the fusing lithium at 200 ℃.So obtain to comprise the lithium metal of 2wt% acetylene black and the compound of acetylene black.After cooling, pile up three with acetylene black integrated section, and with small-sized rolling device with their the calendering to obtain the thickness of 400 μ m.The compound that will roll with mould is embossed into disc, thereby obtains the whole negative pole that comprises the compound of lithium metal and acetylene black.The inner surface of the negative electrode casing of insulating packing is installed above described negative pole is crimped onto.Said process all carries out in the argon gas glove box.

The (iii) preparation of organic bath

At gamma-butyrolacton (γ BL: the LiBF4 (LiBF of dissolving 1mol/L concentration nonaqueous solvents) ₄: solute) and used as electrolyte.

The (iv) assembling of battery

Positive pole is placed on the inner bottom surface of anode cover, and obtains round-shaped polypropylene non-woven fabric barrier film (100 μ m are thick) covering with impression.Then, in anode cover, inject electrolyte, with electrolyte-impregnated positive pole and barrier film.Then, with crimping the negative electrode casing of negative pole be connected to anode cover, make negative pole and positive pole face with each other.The coin type battery of sealing is finished to the insulating packing crimping that is connected with negative electrode casing in end around the anode cover.This battery has the diameter of 20mm, the height of 2mm and the design capacity of 100mAh.Be the assembling process above carrying out in-50 ℃ or the lower dry air at dew point.Prepare identical coin type battery, obtain 12 batteries.

Embodiment 2A

Except the negative pole prepared atmosphere being changed over vacuum degree is 100Pa or the lower gas-tight container, prepares negative pole according to the method identical with embodiment 1A.Prepare 10 coin type batteries.

Embodiment 3A

To comprise average grain diameter be that 0.1 μ m and BET specific area are 20m except using ²The furnace black of the primary granule of/g (FB) replace ethine is black; And the furnace black content in the compound of lithium metal and furnace black is set to outside the 5wt%, prepares negative pole according to the method identical with embodiment 1A.Prepare 12 coin type batteries.

Embodiment 4A

To comprise average grain diameter be that 0.03 μ m and BET specific area are 800m except using ²The Ketjen black of the primary granule of/g (KB) replace ethine is black; And the Ketjen black content in the compound of lithium metal and Ketjen black is set to outside the 0.02wt%, prepares negative pole according to the method identical with embodiment 1A.Prepare 12 coin type batteries.

Embodiment 5A

To comprise average grain diameter be that 0.2 μ m and BET specific area are 18m except using ²The carbon black of the primary granule of/g (CB) replace ethine is black; And the content of carbon black in the compound of lithium metal and carbon black is set to outside the 1wt%, prepares negative pole according to the method identical with embodiment 1A.Prepare 10 coin type batteries.

Embodiment 6A

Except using average grain diameter is that 5 μ m and BET specific area are 1600m ²The active carbon replace ethine of/g is black; And the active carbon content in the compound of lithium metal and active carbon is set to outside the 0.5wt%, prepares negative pole according to the method identical with embodiment 1A.Prepare 10 coin type batteries.

Embodiment 7A

Except the negative pole prepared atmosphere being changed over dried nitrogen atmosphere (dew point is-50 ℃ or lower), prepare negative pole according to the method identical with embodiment 1A.Prepare 10 coin type batteries.

Embodiment 8A

Except in propylene carbonate (PC) and 1, concentration of ordinary dissolution is the LiCF of 1mol/L in 1: 1 (volume ratio) mixed solution (nonaqueous solvents) of 2-dimethoxy-ethane (DME) ₃SO ₃(solute) and used as organic bath, and the acetylene black content in the compound of lithium metal and acetylene black is set to outside the 0.1wt%, prepares 10 coin type batteries according to the method identical with embodiment 1A.

Embodiment 9A

Acetylene black content in the compound of lithium metal and acetylene black is set to the 10wt%, prepares negative pole according to the method identical with embodiment 1A.Prepare 10 coin type batteries.

Comparative Examples 1A

Except the lithium sheet metal is embossed into disc not with carbon black integrated and former state as the negative pole, according to method preparation 12 coin type batteries identical with embodiment 1A.

Comparative Examples 2A

Except using average grain diameter is that 2 μ m and BET specific area are 12m ²The Delanium replace ethine of/g is black, and the Delanium content in the compound of lithium metal and Delanium is set to 5wt%; And the negative pole prepared atmosphere is changed over outside the dried air atmosphere, prepare negative pole according to the method identical with embodiment 1A.Prepare 10 coin type batteries.

Embodiment 10A

Except using manganese dioxide (MnO ₂) as positive electrode active materials, and mix MnO with 100: 3: 6 weight ratio ₂, outside Ketjen black (electric conducting material) and the fluorocarbon resin (binding agent :) by the solid constituent of the NEOFLON FEP of DAIKIN INDUSTRIES Co., Ltd preparation, anodal according to the method preparation identical with embodiment 1A.Except using described positive pole; In propylene carbonate (PC) and 1,1: 1 middle concentration of ordinary dissolution of (volume ratio) mixed solution (nonaqueous solvents) of 2-dimethoxy-ethane (DME) is the LiCF of 1mol/L ₃SO ₃Solute and as organic bath; And the acetylene black content in the compound of lithium metal and acetylene black is set to outside the 0.2wt%, prepares 10 coin type batteries according to the method identical with embodiment 1A.

Embodiment 11A

Ketjen black content in the compound of lithium metal and Ketjen black is set to the 0.1wt%, prepares negative pole according to the method identical with embodiment 4A.Except using described negative pole; Use the positive pole identical with embodiment 10A; And in propylene carbonate (PC) and 1,3: 1 middle concentration of ordinary dissolution of (volume ratio) mixed solution (nonaqueous solvents) of 3-dioxolanes are the LiPF of 1mol/L ₆And, prepare 10 coin type batteries according to the method identical with embodiment 1A as outside the organic bath.

Comparative Examples 3A

Except the lithium sheet metal is embossed into disc and former state as negative pole and not with carbon black integrated, according to 10 coin type batteries of the method identical preparation with embodiment 10A.

[evaluation]

(i) initial performance

Under the constant current of 4mA with embodiment 1A to 11A and Comparative Examples 1A to the 3A battery pre-arcing in each 30 minutes.Then, at 60 ℃ with cell degradation stable cell open circuit voltage (OCV) over 1 day.Then, measure the OCV and the impedance under 1kHz of each battery at ambient temperature, and confirm in each battery not unusual.

(discharge capacity)

After aging, under 25 ℃, the constant resistance of 15k Ω, 2 battery discharges in each embodiment and the Comparative Examples to 2V, are checked initial discharge capacity (C ₀).

(heavy-current discharge performance under the low temperature)

After aging, at-40 ℃ 3 battery impulses in each embodiment and the Comparative Examples discharged and to estimate heavy-current discharge performance under the low temperature.Specifically, under the constant current of 3mA, made battery discharge 1 second, and it was left standstill 59 seconds; Repeat 20 circulations of this operation, and measure the pulse voltage value of each circulation.Obtain minimum pulse voltage (V in 20 circulations ₀).

The (ii) performance after the high temperature storage

After aging, estimate the high temperature storing stabilization of 5 batteries in each embodiment and the Comparative Examples.The battery of embodiment 1A to 9A and Comparative Examples 1A and 2A was in statu quo stored 10 days in 80 ℃ after aging.Under the constant current of 0.1mA, make the battery discharge 500 hours (50mAh) of embodiment 10A and 11A and Comparative Examples 3A, and 80 ℃ of storages 10 days.The reason that makes the battery partial discharge of embodiment 10A and 11A and Comparative Examples 3A is when using MnO ₂During as positive electrode active materials, after partial discharge, can observe significant deterioration by storage battery at high temperature.

(discharge capacity)

Be that 80 ℃ have been stored in 10 days the battery, under 25 ℃, the constant resistance of 15k Ω, with 2 battery discharges in each embodiment and the Comparative Examples to 2V, so that check discharge capacity (C after the high temperature storage ₁).

(heavy-current discharge performance under the low temperature)

Be that 80 ℃ have been stored in 10 days the battery, at-40 ℃ 3 battery impulses in each embodiment and the Comparative Examples discharged and estimate heavy-current discharge performance under the low temperature.Specifically, under the constant current of 3mA, made battery discharge 1 second, and it was left standstill 59 seconds; Repeat 20 circulations of this operation, and measure the pulse voltage value of each circulation.Obtain minimum pulse voltage (V in 20 circulations ₁).

Table 1 has shown that positive electrode active materials is C among the embodiment 1A to 9A of fluorographite and Comparative Examples 1A and the 2A ₀, V ₀, C ₁And V ₁Mean value.Table 2 has shown that positive electrode active materials is MnO ₂Embodiment 10A and 11A and Comparative Examples 3A in C ₀, V ₀, C ₁And V ₁Mean value.

Table 1

Table 2

^*The discharge design capacity 50% the back 80 ℃ of storages.

[discussion]

(i) initial performance

From table 1 obviously as seen, at embodiment 1A to 8A in any one, the 2.188V of the minimum voltage in-40 ℃ of pulsed discharges in the Comparative Examples 1A.Therefore, significantly, improved the initial performance of heavy-current discharge under the low temperature.In addition, because discharge capacity among the embodiment 1A to 8A has at ambient temperature surpassed design capacity (100mAh), the others of discharge performance there is not adverse influence.

On the other hand, from using Delanium, promptly between the Comparative Examples 2A of crystalline form carbon materials and embodiment 1A relatively, significantly, by use amorphous carbon cellulosic material, the improvement effect of right-40 ℃ of pulsed discharge performances becomes obvious.This may be because react greater than the electrolytical at the interface reduction decomposition between amorphous carbon cellulosic material and electrolyte in the electrolytical at the interface reduction decomposition reaction between crystalline form carbon materials and electrolyte, and has increased the reaction resistance at the interface that forms at catabolite.

Acetylene black content is big in negative pole, promptly among the embodiment 9A of 10wt%, is lower than design capacity and the decline of energy content of battery density although initial discharge capacity becomes, and sees the improvement effect in-40 ℃ of pulsed discharge performances.The decline of initial discharge capacity may be because big acetylene black content.That is, at the interface the degree of electrolyte reduction decomposition reaction becomes big between acetylene black and electrolyte, and has increased the reaction resistance at the interface that forms at catabolite.Therefore, in order to improve low temperature performance, amorphous carbon cellulosic material content preferably should be set to 5wt% or lower.

Carry out in dried nitrogen atmosphere among the incorporate embodiment 7A of lithium metal and carbon black, initial capacity becomes 101mAh, promptly is lower than the initial capacity of Comparative Examples 1A.In addition ,-40 ℃ of pulsed discharge performances are 2.259V among the embodiment 7, and the improvement effect is less than the improvement effect of carrying out incorporate embodiment 1A to 6A and 8A in argon gas atmosphere or 100Pa or lower vacuum.This may be because lithium that melts in integrated process and nitrogen reaction and formation lithium nitride (Li ₃N).When assemble, Li ₃Very small amount of power and water is separated very small amount of water reaction in the matter in N and the dry air, and causes the reaction that produces lithium hydroxide and electrolyte decomposition.Based on these, can think that the amount of electrolyte and the lithium that may discharge reduces.Therefore, preferably in argon gas atmosphere with carbon black and lithium metal-integral.In addition, when in 100Pa or lower reduced atmosphere during with carbon black and lithium metal-integral, the lithium that has quickened fusing is to the dipping of the little carbon black pellet of porous and bulk density (bulk density).Therefore, the integrated of lithium and carbon black becomes easier.

Comprising average grain diameter in the amorphous carbon cellulosic material is that 0.1 μ m or lower and BET specific area are 20m ²Among the embodiment 1A to 4A of/g or bigger primary granule, do not see the decline of initial discharge capacity, and the minimum voltage in-40 ℃ of pulsed discharges is about 2.3V.That is, in embodiment 1A to 4A, the minimum voltage in-40 ℃ of pulsed discharges has improved 0.1V or bigger than Comparative Examples 1A, and the effect that suppresses the voltage drop of discharge initial stage is big.

When using MnO ₂During as positive electrode active materials, as shown in table 2, the initial discharge capacity of embodiment 10A and embodiment 11A is identical with Comparative Examples 3A almost.On the other hand ,-40 ℃ of pulse discharging voltages are 2.3V or bigger among embodiment 10A and the embodiment 11A, compare with 2.25V among the Comparative Examples 3A and have improved about 0.05V.When using MnO ₂During as positive electrode active materials, because electrolyte also is different, so the polarization percentage contribution (polarizationcontribution degree) of positive pole and negative pole may change under negative pole and electrolytical interfacial reaction and the low temperature discharge.But, even the result in the table 2 shows when using MnO ₂During as positive electrode active materials, also can obtain and use fluorographite as the identical improvement effect of the situation of positive electrode active materials.

In the atmosphere of doing, take the battery after the pre-arcing in embodiment 1A, 3A and 4A and Comparative Examples 1A apart, and take out negative pole.With the negative pole of DME (1, the 2-dimethoxy-ethane) washing taking-up, and carry out XPS (x-ray photoelectron spectroscopy) and analyze.5600 types that use the preparation of PhysicalElectronics company are as analytical equipment, and use Al-K α (14kV/400W) is as X-ray light source.Carry out etching by the argon ion sputtering under the 3kV accelerating voltage.Under these conditions, pass through SiO ₂Convert, speed is 7.4nm/min.Element of measuring and zone are set to Lils (65-45eV), Bls (200-180eV), Cls (294-274eV), Ols (542-522eV) and Fls (695-675eV).After each etching, carry out XPS analysis, and measure the amount of the definite element that exists of peak area of element from each.Shown among Fig. 2 apart from the negative pole degree of depth and mol ratio F/Li in the face of anodal negative terminal surface, the relation between the mol ratio of the relative lithium atom of fluorine atom that promptly detects.In addition, shown among Fig. 3 apart from the negative pole degree of depth and mol ratio F/O in the face of anodal negative terminal surface, the relation between the mol ratio of the relative oxygen atom of fluorine atom that promptly detects.

Fig. 2 shows near the negative terminal surface of Comparative Examples 1A (Comparative Examples 1) and has a large amount of fluorine atoms, and the amount of fluorine atom reduces towards negative pole is inner.Negative terminal surface only contains in the situation of lithium metal in Comparative Examples 1A, produces than relatively large lithium fluoride (LiF).Think that LiF is by solute (LiBF ₄) decomposition reaction and Li and from fluorographite, i.e. reaction between the fluorine ion of escaping in the positive electrode active materials produces.On the other hand, in embodiment 1A (embodiment 1), embodiment 3A (embodiment 3) and embodiment 4A (embodiment 4), the amount of the middle fluorine atom that exists is less than Comparative Examples 1A near the negative terminal surface.In addition, particularly the mol ratio F/Li apart from surperficial 5-15nm degree of depth place is 0.7 or littler, and this shows that the generation of LiF is little.

Near the negative terminal surface oxygen atom is mainly as lithia (Li ₂O) also as lithium carbonate ((Li ₂CO ₃) exist, lithium carbonate is the catabolite of solvent.The amount of oxygen atom reduces towards negative pole is inner.Obviously as seen near the negative terminal surface of Comparative Examples 1A (Comparative Examples 1), the amount of the fluorine atom of existence (LiF) is the two or three times of oxygen atom from Fig. 3.On the other hand, in embodiment 1A (embodiment 1), embodiment 3A (embodiment 3) and embodiment 4A (embodiment 4), near the amount of the fluorine atom that exists the negative terminal surface is 1-1.5 a times of oxygen atom amount.Especially the mol ratio F/O apart from surperficial 5-15nm degree of depth place is 1.3 or littler.This shows from negative terminal surface and to have a large amount of lithias and lithium carbonate to the 5-15nm degree of depth, only produces a spot of LiF.

As mentioned above, the amount that effect of the present invention relates to the oxygen atom that makes near negative terminal surface (especially apart from surperficial 5-15nm place) existence is big, and reduces the amount of fluorine atom.By increasing the amount of oxygen atom, and by reducing the amount of fluorine atom, when high temperature storage, stable interface can be between lithium and electrolyte, formed, and heavy-current discharge performance after the high temperature storage or the heavy-current discharge performance under the low temperature can be improved.

Effect of the present invention is by control negative pole and electrolytical interfacial reaction, reduces the reaction resistance of negative pole, and improves the discharge voltage under the low temperature discharge.Therefore, as long as use solid-state positive electrode active materials, effect of the present invention does not have very big-difference, even and by using various oxides can obtain identical effect with fluoride yet.

The (ii) performance after the high temperature storage

As for the discharge capacity after the high temperature storage, because in any one, remained the capacity identical with Comparative Examples 1A at embodiments of the invention 1A-7A, i.e. 100mAh, or bigger capacity, it is less that the capacity that is caused by high temperature storage reduces.But, using Delanium, promptly among the Comparative Examples 2A of crystalline form carbon materials, capacity is 95mAh, and the deterioration that high temperature storage causes is big.

In addition, as for the pulse performance under-40 ℃ of low temperature, Comparative Examples 1A shows and drops to 1.92V, and any one shows as 2V or bigger among embodiment 1A-9A and the Comparative Examples 2A, has realized the improvement effect of low temperature performance after the high temperature storage.Especially in embodiment 1A-8A, obtain 2.1V or bigger high discharge voltage.Wherein, comprising average grain diameter at carbon black is that 0.1 μ m or littler and BET specific area are 20m ²Among the embodiment 1A-4A of/g or bigger primary granule, discharge voltage is about 2.25V, and has obviously obtained the improvement effect of discharge performance.

As for electrolytical effect, in PC and DME solvent mixture, dissolve LiCF ₃SO ₃Embodiment 8A in ,-40 ℃ inceptive impulse discharge voltage is 2.313V, promptly than dissolve LiBF in γ BL ₄The high 0.02V of embodiment 1A.After 80 ℃ of storages, the pulse discharging voltage of discharge capacity and-40 ℃ becomes and is lower than embodiment 1A among the embodiment 8A.Battery among the embodiment 8A after the storage is had a few and is expanded, and may be because the gas that produces from high temperature storage becomes more, and capacity reduces and the reduction of low temperature pulse performance is big.Therefore, obviously visible the use dissolved LiBF in γ BL ₄Electrolyte the lithium primary battery aspect of excellence is favourable aspect stability under the high temperature and the storage characteristics obtaining.

In the battery in Comparative Examples 3A after 80 ℃ of storages, the 28mAh that only discharges, i.e. about half of residual capacity (50mAh), and in the battery in embodiment 10A and 11A, obtain the discharge capacity of 46mAh and 43mAh respectively.In addition, equally after 80 ℃ of storages in-40 ℃ of pulsed discharges, the decline among the Comparative Examples 3A is big, promptly reduce to 1.85V, and in embodiment 10A and 11A, voltage is reduced to 2.185V and 2.204V respectively, shows the big improvement in storage characteristics aspect under the high temperature.Therefore, even in using the situation of oxide as positive electrode active materials, by using and the incorporate negative pole of amorphous carbon cellulosic material of the present invention, controlled the interfacial reaction between negative pole and electrolyte, and can obtain to suppress the effect that the negative reaction resistance increases, and can improve the storage characteristics under the high temperature greatly.

As result to each battery AC impedance measurement, in embodiment and Comparative Examples, use with carbon materials integrated any battery of negative pole in, camber line partly becomes less than the camber line part of using the battery of the negative pole that comprises lithium simple substance in Comparative Examples 1A and 3A.This may be because reaction resistance force diminishes between negative pole and electrolyte at the interface.But, because the correlation between the minimum voltage the reaction Resistance Value of estimating from the diameter of the reaction camber line that obtains by the Cole-Cole curve and-40 ℃ of pulsed discharges is unclear, so can not be from the improvement effect of AC impedance measurements estimation discharge performance.The result of AC impedance also is similar to correlation between the discharge performance in the battery after 80 ℃ of storages.

Embodiment 12A

Except the content of acetylene black (AB) is set to the 0.2wt%, obtain the compound of lithium metal and acetylene black from the section of the thick lithium sheet metal of 150 μ m according to the method identical with embodiment 1A.After the cooling, pile up with acetylene black integrated section and the thick lithium sheet metal of 250 μ m, and with roll squeezer calendering, obtain the thickness of 350 μ m.The product that uses mould to have rolled is embossed into disc, obtains comprising the negative pole of the underclad portion of the top layer part of compound and lithium metal.With the negative pole of cooled with liquid nitrogen gained, tangent plane is observed in cutting on thickness direction then.As a result, the thickness of top layer part is about 110-120 μ m.Except the negative pole that uses gained, prepare coin type battery according to the method identical with embodiment 1A.

Fig. 4 has shown the schematic sectional view of gained negative pole 5.Negative pole 5 comprises top layer part 13 and underclad portion 12, and top layer part 13 contains the compound of acetylene black and lithium metal, and underclad portion 12 contains the lithium metal simple-substance.

Embodiment 13A

Except the negative pole prepared atmosphere being changed over vacuum degree is 100Pa or lower reduced atmosphere; The thickness of the section of lithium sheet metal is changed into 360 μ m; Use that to comprise average grain diameter be that 0.1 μ m and BET specific area are 20m ²The furnace black of the primary granule of/g (FB) replace ethine is black; And the heating-up temperature that sprays the section of furnace black in its surface is set to outside 150 ℃, obtains the compound of lithium metal and furnace black according to the method identical with embodiment 1A.After the cooling, with roll squeezer calendering and furnace black integrated section, obtain the thickness of 350 μ m, and use mould that it is embossed into disc, obtain negative pole.When observation post got the section of negative pole, it was about 10-15 μ m that there is the thickness of the top layer part of furnace black in discovery.When supposition thickness was 15 μ m, the furnace black content in the part of top layer was 5wt%.Except using this negative pole, according to method preparation 10 coin type batteries identical with embodiment 1A.

Embodiment 14A

Except the negative pole prepared atmosphere being changed over vacuum degree is 100Pa or lower reduced atmosphere; The thickness of lithium sheet metal is changed into 100 μ m; Use that to comprise average grain diameter be that 0.2 μ m and BET specific area are 18m ²The carbon black of the primary granule of/g (CB) replace ethine is black; And content of carbon black is changed into outside the 1wt%, obtained the compound of lithium metal and carbon black according to the method identical with embodiment 1A.After the cooling, with roll squeezer calendering and carbon black integrated section, obtain the thickness of 70 μ m, and it is piled up with the thick lithium sheet metal of 280 μ m and use die marks to become disc, obtain to comprise the negative pole of the underclad portion of the top layer part of compound and lithium metal.Except using the gained negative pole, according to method preparation 10 coin type batteries identical with embodiment 1A.

Embodiment 15A

Except the negative pole prepared atmosphere being changed over vacuum degree is 100Pa or lower reduced atmosphere; The thickness of lithium sheet metal is changed into 30 μ m; Use that to comprise average grain diameter be that 0.04 μ m and BET specific area are 50m ²The carbon black of the primary granule of/g (CB) replace ethine is black; And content of carbon black is set to outside the 0.02wt%, obtains the compound of lithium metal and carbon black according to the method identical with embodiment 1A.After the cooling, make with carbon black integrated section and 320 μ m are thick and lithium-aluminium alloy that comprise 1wt%Al piles up, and use die marks to become disc, obtain to comprise the negative pole of the underclad portion of the top layer part of compound and lithium alloy.Except using the gained negative pole, according to method preparation 10 coin type batteries identical with embodiment 1A.

Embodiment 16A

Except using average grain diameter is that 5 μ m and BET specific area are 1600m ²The active carbon of/g replaces carbon black; And the active carbon content in the compound of lithium metal and active carbon is set to outside the 2wt%, prepares negative pole according to the method identical with embodiment 14A.Prepare 10 coin type batteries.

Embodiment 17A

Except the negative pole prepared atmosphere being changed over dried nitrogen atmosphere (dew point is-50 ℃ or lower), prepare negative pole according to the method identical with embodiment 14A.Prepare 10 coin type batteries.

Embodiment 18A

Except the acetylene black content that comprises in the part of top layer is set to 10wt%, and the thickness of top layer part is set to prepare negative pole according to the method identical with embodiment 12A outside about 200 μ m (thickness of whole negative pole is 350 μ m).Prepare 10 coin type batteries.

Comparative Examples 4A

Except using average grain diameter is that 2 μ m and BET specific area are 12m ²The Delanium replace ethine of/g is black, and the Delanium content in the part of top layer is set to 1wt%; And the negative pole prepared atmosphere is changed over outside the dried air atmosphere, prepare negative pole according to the method identical with embodiment 12A.Prepare 10 coin type batteries.

Embodiment 19A

Except using anodal and with the embodiment 10A identical organic bath identical, prepare 10 coin type batteries according to the method identical with embodiment 12A with embodiment 10A.

Embodiment 20A

Except using average grain diameter is that 0.03 μ m and BET specific area are 800m ²It is that 0.2 μ m and BET specific area are 18m that the Ketjen black of/g replaces average grain diameter ²Outside the carbon black of/g, prepare negative pole according to the method identical with embodiment 14A.Except using this negative pole and the organic bath identical, prepare 10 coin type batteries according to the method identical with embodiment 19A with embodiment 11A.

Comparative Examples 5A

Except lithium sheet metal former state is embossed into disc and as negative pole and not with carbon black integrated, according to 10 coin type batteries of the method identical preparation with embodiment 19A.

[evaluation]

(i) initial performance

Under the constant current of 4mA, make embodiment 12A to 20A and Comparative Examples 4A to the 5A battery pre-arcing in each 30 minutes.Then, at 60 ℃ with cell degradation stable cell open circuit voltage (OCV) over 1 day.Then, measure the OCV and the impedance under 1kHz of each battery at ambient temperature, and confirm in each battery not unusual.

(discharge capacity)

(heavy-current discharge performance under the low temperature)

The (ii) performance after the high temperature storage

After aging, estimate the high temperature storing stabilization of 5 batteries in each embodiment and the Comparative Examples.The battery of embodiment 12A to 18A and Comparative Examples 4A was stored 10 days in 80 ℃ of former states in aging back.Under the constant current of 0.1mA, make the battery discharge 500 hours (50mAh) of embodiment 19A and 20A and Comparative Examples 5A, then 80 ℃ of storages 10 days.Because when using MnO ₂During as positive electrode active materials, after partial discharge, can observe significant deterioration by storage battery at high temperature, so that the battery partial discharge of embodiment 19A and 20A and Comparative Examples 5A.

(discharge capacity)

(heavy-current discharge performance under the low temperature)

Table 3 has shown that positive electrode active materials is C among the embodiment 12A to 18A of fluorographite and the Comparative Examples 4A ₀, V ₀, C ₁And V ₁Mean value.Table 4 has shown that positive electrode active materials is MnO ₂Embodiment 19A and 20A and Comparative Examples 5A in C ₀, V ₀, C ₁And V ₁Mean value.

Table 3

Table 4

^*The discharge design capacity 50% the back 80 ℃ of storages.

Obviously as seen, in any one, the minimum voltage of-40 ℃ of pulsed discharges is far above the 2.188V among the Comparative Examples 1A, the improvement that shows initial performance in the low-temperature high-current discharge at embodiment of the invention 12A to 17A from table 3.In addition, because discharge capacity in each embodiment has at ambient temperature surpassed design capacity (100mAh) equally, the others of discharge performance there is not adverse influence.

On the other hand, from embodiment 12A with use Delanium, promptly between the Comparative Examples 4A of crystalline form carbon materials relatively, obviously visible by using the amorphous carbon cellulosic material, the improvement effect of right-40 ℃ of pulsed discharge performances becomes obvious.This may be because react greater than the electrolytical at the interface reduction decomposition between amorphous carbon cellulosic material and electrolyte in the electrolytical at the interface reduction decomposition reaction between crystalline form carbon materials and electrolyte, and has increased the reaction resistance at the interface that forms at catabolite.

Acetylene black content is big in the top layer, be that the thickness of 10wt% and top layer part surpasses among half the embodiment 18A of whole negative pole, be lower than design capacity and the decline of energy content of battery density although initial discharge capacity becomes, in-40 ℃ of pulsed discharge performances, see the improvement effect.The decline of initial discharge capacity may be because big acetylene black content.That is, at the interface the degree of electrolyte reduction decomposition reaction becomes big between acetylene black and electrolyte, and has increased reaction resistance at the interface.Therefore, in order to improve low temperature performance, the amorphous carbon cellulosic material content of top layer part preferably is set to 5wt% or lower, and the thickness of top layer part preferably be set to whole negative pole 1/3 or littler.

Carry out in dried nitrogen atmosphere among the incorporate embodiment 17A of lithium metal and carbon black, initial capacity becomes 101mAh, promptly is lower than the initial capacity of Comparative Examples 1A.In addition ,-40 ℃ of pulsed discharge performances are 2.245V among the embodiment 17A, and the improvement effect is lower than the improvement effect of carrying out incorporate embodiment 12A to 15A in argon gas atmosphere or 100Pa or lower vacuum.This may be because lithium that melts in integrated process and nitrogen reaction and formation lithium nitride (Li ₃N).When assemble, Li ₃Very small amount of power and water in N and the dry air is separated very small amount of water reaction in the matter, and causes the reaction that produces lithium hydroxide and electrolyte decomposition.Based on these, can think that the amount of electrolyte and the lithium that may discharge reduces.Therefore, preferably in argon gas atmosphere with carbon black and lithium metal-integral.In addition, when in 100Pa or lower reduced atmosphere during with carbon black and lithium metal-integral, the lithium that has quickened fusing is to the dipping of the little carbon black pellet of porous and bulk density.Therefore, the integrated of lithium and carbon black becomes easier.

Comprising average grain diameter in the amorphous carbon cellulosic material is that 0.1 μ m or lower and BET specific area are 20m ²Among embodiment 12A, the 13A and 15A of/g or bigger primary granule, do not see the decline of initial discharge capacity, and the minimum voltage in-40 ℃ of pulsed discharges is about 2.3V.That is, in embodiment 12A, 13A and 15A, the minimum voltage in-40 ℃ of pulsed discharges is about 2.3V, and the effect that suppresses the voltage drop of discharge initial stage is big.

When using MnO ₂During as positive electrode active materials, as shown in table 4, the initial discharge capacity of embodiment 19A and 20A is identical with Comparative Examples 5A almost.But-40 ℃ pulse discharging voltage is 2.34V or bigger, compares with 2.25V among the Comparative Examples 5A and has improved about 0.1V.When using MnO ₂During as positive electrode active materials, because electrolyte also is different, so the polarization percentage contribution of positive pole and negative pole may change under negative pole and electrolytical interfacial reaction and the low temperature discharge.But, even the result in the table 4 shows when using MnO ₂During as positive electrode active materials, also can obtain and use fluorographite as the identical improvement effect of the situation of positive electrode active materials.

As for the discharge capacity after the high temperature storage, in any embodiment of the present invention, remained the capacity identical or bigger with Comparative Examples 1A, it is little that the capacity under the high temperature storage reduces.But, using Delanium, promptly among the Comparative Examples 4A of crystalline form carbon materials, it is about 10% to see that capacity reduces, and the deterioration that high temperature storage causes is big.

In addition, as for the pulse performance under-40 ℃ of low temperature, Comparative Examples 1A shows and drops to 1.92V, and any one shows as 2V or bigger among embodiment 12A-18A and the Comparative Examples 4A, has realized the improvement effect of low temperature performance after the high temperature storage.Especially in embodiment 12A-17A, obtain 2.1V or bigger high discharge voltage.Wherein, comprising average grain diameter at carbon black is that 0.1 μ m or littler and BET specific area are 20m ²Among embodiment 12A, the 13A and 15A of/g or bigger primary granule, discharge voltage is about 2.25V, and has obviously obtained the improvement effect of discharge performance.

In the battery in Comparative Examples 5 after 80 ℃ of storages, the 28mAh that only discharges, i.e. about half of residual capacity (50mAh), and in the battery in embodiment 19A and 20A, obtain the discharge capacity of 45mAh and 43mAh respectively.In addition, equally after 80 ℃ of storages in-40 ℃ of pulsed discharges, the decline among the Comparative Examples 5A is big, promptly reduce to 1.85V, and in embodiment 19A and 20A, voltage is reduced to 2.238V and 2.201V respectively, shows the big improvement in storage characteristics aspect under the high temperature.Therefore, even even in using the situation of oxide as positive electrode active materials, by using and the incorporate negative pole of amorphous carbon cellulosic material of the present invention, controlled the interfacial reaction between negative pole and electrolyte, and can obtain to suppress the effect that the negative reaction resistance increases, and can improve the storage characteristics under the high temperature greatly.

From The above results, obviously as seen comprise the negative pole of amorphous carbon cellulosic material, even at the heavy-current discharge performance that also can improve greatly after the high temperature storage under the low temperature by use.But when using the crystalline form carbon materials, in the consumption of amorphous carbon cellulosic material was big situation, perhaps in the top layer part was thick situation, the improvement effect was little.In the case, suppose between negative pole and electrolyte the electrolyte decomposition reaction of generation at the interface and at the described catabolite that accumulates at the interface, form new reaction resistance.

As result to each battery AC impedance measurement, in embodiment and Comparative Examples, use with carbon materials integrated any battery of negative pole in, camber line partly becomes less than the camber line part of using the battery of the negative pole that comprises lithium simple substance in Comparative Examples 4A and 5A.This may be because reaction resistance force diminishes between negative pole and electrolyte at the interface.But, because the correlation between the minimum voltage the reaction Resistance Value of estimating from the diameter of the reaction camber line that obtains by the Cole-Cole curve and-40 ℃ of pulsed discharges is unclear, so can not be from the improvement effect of AC impedance measurements estimation discharge performance.The result of AC impedance also is similar to correlation between the discharge performance in the battery after 80 ℃ of storages.

Embodiment 1B

(i) Zheng Ji preparation

For positive electrode active materials, petroleum coke fluoridized and as fluorographite (CF _x: x=1.02).With 100: 15: 6 weight ratio mixed fluoride graphite, acetylene black (electric conducting material) and styrene butadiene rubbers (SBR) (binding agent), and the mixed solution of water and ethanol is fully mediated them as decentralized medium.Behind 100 ℃ of dry gained mixtures, come compression molded described mixture to obtain the disk shape by using predetermined mould and hydraulic press, thereby obtain anodal.

The (ii) preparation of negative pole

Use the lithium metal as negative active core-shell material, and use Al by the preparation of Sumitomo Chemical Co., Ltd ₂O ₃(production number AA07) is as particulate.Al ₂O ₃The average grain diameter of primary granule be 0.7 μ m, and the BET specific area is 10m ²/ g.Under reduced pressure in 120 ℃ of dry Al ₂O ₃, be introduced into then in the negative pole prepared atmosphere (argon gas atmosphere).

The lithium sheet metal that 200 μ m are thick is introduced in the negative pole prepared atmosphere, and with 9g/m ²The speed dry down Al that crosses of spraying decompression in its surface equably ₂O ₃Then.Use rolling device to roll described lithium sheet metal, be inserted with the thick polyethylene film of 40 μ m therebetween.The sheet that uses mould roll is embossed into disc, thus acquisition the has had embedding negative pole of top layer part of particulate.As shown in fig. 1, insulating packing is installed above described negative pole is crimped onto the inner surface of negative electrode casing 2 on.

Fig. 5 has shown the schematic sectional view of gained negative pole 5.Negative pole 5 comprises lithium 12, and in its top layer part, be scattered and embedding Al ₂O ₃Particulate 11.A part of primary granule of formation secondary granule is fixed near surface and is not embedded in the part of top layer.

The (iii) preparation of organic bath

To gamma-butyrolacton (γ BL: the LiBF4 (LiBF of dissolving 1mol/L concentration nonaqueous solvents) ₄: solute) and used as electrolyte.

The (iv) assembling of battery

Positive pole 4 is placed on the inner bottom surface of anode cover 1, and obtains round-shaped polypropylene non-woven fabric barrier film 6 (100 μ m are thick) covering with impression.Then, in anode cover 1, inject electrolyte, with electrolyte-impregnated anodal 4 and barrier film 6.Then, with crimping the negative electrode casing 2 of negative pole 5 be connected on the anode cover 1, make negative pole 5 and anodal 4 face with each other.The coin type battery 10 of sealing is finished to insulating packing 3 crimpings that are connected with negative electrode casing 2 in end around the anode cover 1.This battery has the diameter of 23mm, the height of 2mm and the design capacity of 110mAh.Be the assembling process above carrying out in-50 ℃ or the lower dry air at dew point.Prepare identical coin type battery, obtain 10 batteries.

Comparative Examples 1B

Except embedding Al in the part of negative pole top layer not ₂O ₃Particulate, and the lithium sheet metal is embossed into disc and as outside the negative pole, according to 10 coin type batteries of method preparation identical with embodiment 1B.

Embodiment 2B

(by the preparation of Nippon Graphite Industries Co., Ltd, average grain diameter is 2 μ m (primary granule), and the BET specific area is 15m except using Delanium ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 3B

Except using α-Fe ₂O ₃(outside Kojundo Chemical Laboratory Co., Ltd system particulate, according to 10 coin type batteries of method preparation identical with embodiment 1B.

Embodiment 4B

Except using Li ₃PO ₄(by the preparation of Kanto Chemical Co., Ltd, average grain diameter is 2 μ m (primary granule), and the BET specific area is 2.6m ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 5B

Except using SiO ₂(by the preparation of Kojundo Chemical Laboratory Co., Ltd, average grain diameter is 0.5 μ m (primary granule), and the BET specific area is 50m ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 6B

(by Denki Kagaku Kogyo Kabushiki Kaisha preparation, average grain diameter is 0.04 μ m (primary granule), and the BET specific area is 60m except using acetylene black ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 7B

Except in propylene carbonate (PC) and 1, concentration of ordinary dissolution are the LiCF of 1mol/L in 3: 1 (volume ratio) solvent mixture (nonaqueous solventss) of 2-dimethoxy-ethane (DME) ₃SO ₃(solute) and as outside the organic bath prepares 10 coin type batteries according to the method identical with embodiment 1B.

Embodiment 8B

(average grain diameter is that 0.1 μ m (primary granule), BET specific area are 50m except using carbon black ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 9B

(average grain diameter is that 0.03 μ m (primary granule), BET specific area are 800m except using Ketjen black ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 10B

(average grain diameter is that 1 μ m (primary granule), BET specific area are 20m except using petroleum coke ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 11B

(average grain diameter is that 2 μ m (primary granule), BET specific area are 8m except using the SiC particulate ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 12B

Except using ZrO ₂(average grain diameter is that 1 μ m (primary granule), BET specific area are 5m to particulate ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 13B

Except using Li ₂SO ₄(average grain diameter is that 2 μ m (primary granule), BET specific area are 1.8m to particulate ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Embodiment 14B

(average grain diameter is that 2 μ m (primary granule), BET specific area are 1500m except using micro activated carbon particle ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Comparative Examples 2B

Except using SiO ₂(average grain diameter is that 15 μ m (primary granule), BET specific area are 2m ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

Comparative Examples 3B

Except using SiO ₂(average grain diameter is that 5 μ m (primary granule), BET specific area are 7m ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 1B.

[estimating 1]

Under the constant current of 5mA, make embodiment 1B to 14B and Comparative Examples 1B to the 3B battery pre-arcing in each 30 minutes.Then, at 60 ℃ with cell degradation stable cell open circuit voltage (OCV) over 1 day.Then, measure the OCV and the impedance under 1kHz of each battery at ambient temperature, and confirm in each battery not unusual.

(discharge capacity)

After aging, under the constant resistance of 15k Ω, 25 ℃ with three battery discharges in each embodiment and the Comparative Examples to 2V, check initial discharge capacity (C ₀).Table 5 has shown the mean value of three batteries.

(heavy-current discharge performance under the low temperature)

After aging, at-40 ℃ 3 battery impulses in each embodiment and the Comparative Examples discharged and to estimate heavy-current discharge performance under the low temperature.Specifically, under the constant current of 10mA, made battery discharge 1 second, and it was left standstill 59 seconds; Repeat 30 circulations of this operation, and measure the pulse voltage value of each circulation.Obtain initial low temperature pulse voltage (V minimum in 30 circulations ₀).Table 5 has shown the mean value of three batteries.

Table 5

Obviously as seen, in the battery of any one embodiment, the minimum voltage of-40 ℃ of pulsed discharges is far above the 2.125V among the Comparative Examples 1B from table 5, improved heavy-current discharge performance initial under the low temperature.In addition, in the battery of any one embodiment, can obtain with the initial discharge capacity of Comparative Examples quite or bigger initial discharge capacity (design capacity 110mAh or bigger).Therefore, although initial heavy-current discharge performance has improved under the low temperature, do not reduce the others of discharge performance.

Especially be embodiment 6B, 8B and the 9B of 0.1 μ m or littler carbon granule using average grain diameter, and use the BET specific area to be 20m ²Among embodiment 6B, 8B, 9B and the 10B of/g or bigger carbon granule ,-40 ℃ pulse discharging voltage is 2.38V or higher, compares 0.25V or the bigger improvement effect of having obtained with Comparative Examples 1B.

Generally speaking, think and between the average grain diameter of carbon materials and specific area, have to a certain degree correlation.But, be among 0.04 μ m or the littler embodiment 6B and 9B in average grain diameter, and average grain diameter is that 1 μ m and specific area are 20m ²Among the embodiment 10B of/g, pulse discharging voltage is not seen big difference.Above-mentioned situation shows for the improvement of the discharge performance particle diameter of particulate not only, and the specific area of particulate all is important factor.This depends on that with the effect that improves performance electrolyte decomposition reaction and product are consistent in the relevant thought of the protective layer of negative terminal surface formation.

In addition, be that 0.1 μ m or littler and BET specific area are 20m using average grain diameter ²Among/g or bigger embodiment 6B, the 8B and 9B of carbon black as particulate ,-40 ℃ pulse discharging voltage is about 3.4V, shows that discharge performance improves greatly.

Using average grain diameter is the oarse-grained Comparative Examples 2B of 15 μ m, and to use average grain diameter be that-40 ℃ pulse discharging voltage has improved about 0.05V among the Comparative Examples 3B of particle of 5 μ m.But when comparing with each embodiment of the present invention, the improvement effect becomes very little.In addition, the discharge capacity of Comparative Examples 2B is 108mAh, compares with Comparative Examples 1B and shows reduction, although this reduction is slight.Therefore, when using bulky grain, can expect to the disadvantageous effect of discharge performance.

Embodiment 15B

Except using manganese dioxide (MnO ₂) as positive electrode active materials, and mix MnO with 100: 3: 6 weight ratio ₂, outside Ketjen black (electric conducting material) and the fluorocarbon resin (binding agent :) by the solid constituent of the NEOFLON FEP of DAIKIN INDUSTRIES Co., Ltd preparation, anodal according to the method preparation identical with embodiment 1B.By using this positive pole, except in propylene carbonate (PC) and 1, concentration of ordinary dissolution is the LiCF of 1mol/L in 1: 1 (volume ratio) solvent mixture (nonaqueous solvents) of 2-dimethoxy-ethane (DME) ₃SO ₃(solute) as outside the organic bath, according to the method identical with the embodiment 1B coin type battery that to prepare 10 design capacities be 100mAh.

Embodiment 16B

(by the preparation of Nippon Graphite Industries Co., Ltd, average grain diameter is 2 μ m, and the BET specific area is 15m except using Delanium ²The primary granule of/g) replaces Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 15B.

Embodiment 17B

(average grain diameter is 0.03 μ m, and the BET specific area is 800m except using Ketjen black ²/ g) replace Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 15B.

Embodiment 18B

(average grain diameter is 0.1 μ m, and the BET specific area is 50m except using carbon black ²The primary granule of/g) replaces Al ₂O ₃Outside the particulate, according to method preparation 10 coin type batteries identical with embodiment 15B.

Comparative Examples 4B

In the part of negative pole top layer, the embedding particulate, do not prepare 10 coin type batteries except the lithium sheet metal being embossed into disc and former state as negative pole according to the method identical with embodiment 15B.

[estimating 2]

Under the constant current of 5mA, make embodiment 15B to 18B and the Comparative Examples 4B battery pre-arcing in each 30 minutes.Then, at 60 ℃ with cell degradation stable cell open circuit voltage (OCV) over 1 day.Then, measure the OCV and the impedance under 1kHz of each battery at ambient temperature, and confirm in each battery not unusual.

(discharge capacity)

After aging, under the constant resistance of 15k Ω, 25 ℃ with three battery discharges in each embodiment and the Comparative Examples to 2V, check initial discharge capacity (C ₀).Table 6 has shown the mean value of three batteries.

(heavy-current discharge performance under the low temperature)

After aging, at-40 ℃ three battery impulses in each embodiment and the Comparative Examples discharged and to estimate heavy-current discharge performance under the low temperature.Specifically, under the constant current of 12mA, made battery discharge 1 second, and it was left standstill 59 seconds; Repeat 20 circulations of this operation, and measure the pulse voltage value of each circulation.Obtain initial low temperature pulse voltage (V minimum in 20 circulations ₀).Table 6 has shown the mean value of three batteries.

Table 6

Obviously as seen, in the battery of any one embodiment, the minimum voltage of-40 ℃ of pulsed discharges far surpasses the 2.255V among the Comparative Examples 4B, shows the improvement of initial heavy-current discharge performance at low temperatures from table 6.In addition, in the battery of any one embodiment, obtained with the initial discharge capacity of Comparative Examples quite or bigger initial discharge capacity (design capacity of 100mAh).Therefore, although initial heavy-current discharge performance has improved under the low temperature, do not reduce the others of discharge performance.

Especially be that-40 ℃ pulse discharging voltage is 2.36V or higher, compares 0.11V or the bigger improvement effect of having obtained with Comparative Examples 4B among the embodiment 17B and 18B of 0.1 μ m or littler carbon granule using average grain diameter.

As mentioned above, even under the oxide anode active material,, also obtained to improve the effect of heavy-current discharge performance at low temperatures by embedding particulate in the part of negative pole top layer.Especially be that 0.1 μ m or littler charcoal particle and BET specific area are 20m when using average grain diameter ²When/g or bigger charcoal particle, obtained significant effect.

[estimating 3]

After aging, the stability when using embodiment 1B, 2B, 6B, 7B and 8B and Comparative Examples 1B and 2B four batteries in each to estimate high temperature storage.Battery with each after aging was 100 ℃ of storages 5 days.

(discharge capacity)

Be in 100 ℃ of batteries of having stored after 5 days, under 25 ℃, the constant resistance of 15k Ω, with two battery discharges in each embodiment and the Comparative Examples to 2V, check the discharge capacity (C after the high temperature storage ₁).Table 7 has shown the mean value of two batteries.

(heavy-current discharge performance under the low temperature)

Be that 100 ℃ have been stored in 5 days the battery, at-40 ℃ two battery impulses in each embodiment and the Comparative Examples discharged and estimate heavy-current discharge performance under the low temperature.Specifically, under the constant current of 12mA, made battery discharge 1 second, and it was left standstill 59 seconds; Repeat 20 circulations of this operation, and measure the pulse voltage value of each circulation.Obtain initial low temperature pulse voltage (V minimum in 20 circulations ₁).Table 7 has shown the mean value of two batteries.

Table 7

Using LiBF ₄/ γ BL is as among the electrolytical embodiment 1B, even discharge capacity is that 101mAh and low temperature pulse voltage are 2.115V after high temperature storage, this is better than Comparative Examples 1B.On the other hand, using LiCF ₃SO ₃/ (PC+DME) as among the electrolytical embodiment 7B, storage back discharge capacity is that 97mAh and low temperature pulse voltage drop to 2.084V, shows than deterioration bigger among embodiment 1B, 2B and the 6B.Because the battery among the embodiment 7B after the storage a bit expands,, produce than relatively large gas, thereby cause deterioration greatly so can think because high temperature storage has been carried out the electrolyte decomposition reaction.Therefore, from improving the angle of high-temperature stability, use LiBF ₄/ γ BL is better as electrolyte.

In Comparative Examples 2B, the capacity after the high temperature storage drops to 94mAh, shows by high temperature storage, and Capacity Ratio Comparative Examples 1B descends greatlyyer.Because the discharge capacity before the storage is somewhat low, i.e. 108mAh is so exist big particle may cause the reduction of uneven exoelectrical reaction and capacity between positive pole and negative pole.

In using the embodiment 2B of Delanium as particulate, the capacity after the high temperature storage is that 105mAh and low temperature pulse voltage are 2.129V, has realized excellent result.In addition, be that 0.1 μ m or littler or BET specific area are 20m in the carbon black average grain diameter ²Among/g or the bigger embodiment 6B and 8B, the low temperature pulse voltage is about 2.2V, has realized more excellent result.

Industrial applicability

Lithium one-shot battery of the present invention is in low-temperature high-current discharge performance, high-temperature storage characteristics, peace Full property and reliability aspect are excellent, and can be used for the power supply of portable electronic installation.

Claims

(according to the modification of the 19th of treaty)

1. lithium primary battery, it comprises: positive pole, negative pole, organic bath and be inserted in described positive pole and described negative pole between barrier film,

Wherein said negative pole comprises negative active core-shell material, and described negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy; And

The skin section branch of described at least negative pole comprises the compound of amorphous carbon cellulosic material and described negative active core-shell material, and described top layer part is inserted with described barrier film in the face of between described positive pole and they.

2. according to the lithium primary battery of claim 1, wherein said negative pole comprises the described top layer part that contains described compound and contains the underclad portion of described active material.

3. according to the lithium primary battery of claim 1, the content of wherein said amorphous carbon cellulosic material in described negative active core-shell material and described amorphous carbon cellulosic material total amount is 5 weight % or lower.

4. according to the lithium primary battery of claim 1, the thickness that wherein contains the described top layer part of described compound be described negative pole thickness 1/3 or littler.

5. according to the lithium primary battery of claim 1, wherein said positive pole comprises positive electrode active materials, electric conducting material and binding agent, and described positive electrode active materials comprises metal oxide or fluorographite.

6. according to the lithium primary battery of claim 1, wherein said amorphous carbon cellulosic material is to comprise the particulate that average grain diameter is 0.1 μ m or littler primary granule.

7. according to the lithium primary battery of claim 1, wherein said amorphous carbon cellulosic material is that the BET specific area is 20m ²/ g or bigger particulate.

8. according to the lithium primary battery of claim 1, wherein said amorphous carbon cellulosic material be selected from acetylene black, Ketjen black, contact black, furnace black and dim at least a carbon black.

9. according to the lithium primary battery of claim 1, wherein said organic bath comprises the nonaqueous solvents that is used for dissolving solute, and described solute comprises LiBF4, and described nonaqueous solvents comprises gamma-butyrolacton.

10. the preparation method of a lithium primary battery, it comprises the steps:

The preparation negative pole, described negative pole comprises the compound of negative active core-shell material and amorphous carbon cellulosic material at least at the skin section branch of described negative pole, and described negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy, and

Make the described top layer part that comprises described compound towards positive pole, insert barrier film between them.

11., wherein in argon gas atmosphere or in 100Pa or lower reduced atmosphere, implement described preparation comprises the negative pole of described compound at least in the part of described top layer step according to the preparation method of the lithium primary battery of claim 10.

12. according to the preparation method of the lithium primary battery of claim 10, wherein said amorphous carbon cellulosic material is to comprise the particulate that average grain diameter is 0.1 μ m or littler primary granule.

13. according to the preparation method of the lithium primary battery of claim 10, wherein said amorphous carbon cellulosic material is that the BET specific area is 20m ²/ g or bigger particulate.

14. according to the preparation method of the lithium primary battery of claim 10, wherein said amorphous carbon cellulosic material be selected from acetylene black, Ketjen black, contact black, furnace black and dim at least a carbon black.

15. a lithium primary battery, it comprise positive pole, negative pole, organic bath and be inserted in described positive pole and described negative pole between barrier film,

Described negative pole comprises negative active core-shell material, and described negative active core-shell material comprises and is selected from least a in lithium metal and the lithium alloy; And

Described negative pole comprises the top layer part of embedding particulate, and it is 2 μ m or littler primary granule that described particulate comprises average grain diameter (meta particle diameter), and described top layer part is inserted with described barrier film in the face of between described positive pole and they.

16. according to the lithium primary battery of claim 15, wherein said particulate comprises and is selected from Al ₂O ₃, Fe ₂O ₃, SiC, SiO ₂And ZrO ₂In at least a.

17. according to the lithium primary battery of claim 15, wherein said particulate comprises and is selected from Li ₃PO ₄And Li ₂SO ₄In at least a.

18. according to the lithium primary battery of claim 15, wherein said particulate comprises and is selected from least a in graphite, petroleum coke and the active carbon.

Claims

There are halogen atom, lithium atom and oxygen atom at described negative pole apart from the desired depth place that faces in the surperficial 5-15nm scope of described positive pole, and the mol ratio X/Li of halogen atom and lithium atom is 0.7 or lower, and the mol ratio X/O of halogen atom and oxygen atom is 1.3 or lower.

16. a lithium primary battery, it comprise positive pole, negative pole, organic bath and be inserted in described positive pole and described negative pole between barrier film,

17. according to the lithium primary battery of claim 16, wherein said particulate comprises and is selected from Al ₂O ₃, Fe ₂O ₃, SiC, SiO ₂And ZrO ₂In at least a.

18. according to the lithium primary battery of claim 16, wherein said particulate comprises and is selected from Li ₃PO ₄And Li ₂SO ₄In at least a.

19. according to the lithium primary battery of claim 16, wherein said particulate comprises and is selected from least a in graphite, petroleum coke and the active carbon.