JP5625487B2 - Negative electrode for lithium ion secondary battery, lithium ion secondary battery, and method for producing negative electrode for lithium ion secondary battery - Google Patents

Description

  The present invention relates to a negative electrode for a lithium ion secondary battery, a lithium ion secondary battery, and a method for producing a negative electrode for a lithium ion secondary battery.

  Conventionally, in lithium ion secondary batteries, an organic electrolyte is used as an electrolyte. For example, when the battery is short-circuited, overcharged, or left under high temperature, the positive and negative electrode active materials become unstable and reach a certain temperature. Then, an exothermic reaction with the organic electrolyte component in the battery may start gradually. Various methods have been proposed as improvement measures for improving the safety of such non-aqueous electrolyte secondary batteries. For example, a device equipped with a current breaker that mechanically cuts a lead portion through which a current flows using the increase in internal pressure accompanying the temperature rise of the battery (see, for example, Patent Document 1), or a resistance value when the temperature inside the battery becomes high For example, a device including a PTC element in which the number of PTC elements increases (see, for example, Patent Document 2) has been proposed. In addition, a thermosensitive microcapsule is contained inside the battery, and as the battery temperature rises, it is shut down by releasing a polymerizable substance and polymerizing an electrolyte solution (for example, see Patent Document 3). Proposals have been made of using low polypropylene or polyethylene as the separator to cut off the overcurrent due to the shutdown effect of the separator as the battery internal temperature rises.

JP 2000-113834 A JP 11-273651 A JP-A-10-270084

  However, the methods disclosed in Patent Documents 1 and 2 have a problem that the battery configuration becomes complicated. Further, the method of Patent Document 3 has a problem that it takes time for the polymerization reaction. Thus, although what suppresses the heat_generation | fever of a lithium secondary battery is proposed, it is not enough yet, and it was desired to suppress an exothermic reaction in a lithium secondary battery.

  This invention is made | formed in view of such a subject, and provides the negative electrode for lithium ion secondary batteries which can suppress more exothermic reaction in the negative electrode active material containing a carbon material, and a lithium ion secondary battery. The main purpose.

  As a result of diligent research to achieve the above-described object, the inventors of the present invention have mixed carbon additives with an additive containing two or more predetermined compounds together with a graphite negative electrode active material to produce a carbon material. It has been found that the exothermic reaction in the negative electrode active material can be further suppressed, and the present invention has been completed.

That is, the negative electrode for a lithium ion secondary battery according to the present invention includes a negative electrode active material containing a carbon material capable of inserting and extracting lithium, a dicarboxylic acid (R _r [C (═O) OH] ₂ ), a dicarboxylic acid amide ( R _r [C (═O) NH ₂ ] ₂ ), amic acid (R _r [C (═O) OH] [C (═O) NH ₂ ]), dicarboxylic imide (R _r [C (OH) ( = NH)] _2), bis thio carboxylic acid _{(R r [C (= O} ) SH] 2), bis dithio carboxylic acid _{(R r [C (= S} ) SH] 2), Jisurufin acid _{(R r} [S ( ═O) OH] ₂ ), or an alkali metal salt thereof (R is alkyl having 1 to 10 carbon atoms, halogenated alkyl having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, or 6 to 20 carbon atoms. Aryl halides (these alkyls and aryls have substituents, heteroatoms in their structure) And r represents 0 or 1.) 1 selected from 1st group selected from 1), transition element and 12th group, 13th group, 14th group, 15th group element of periodic table And an additive containing at least one second compound selected from oxides, oxoacids, and alkali metal salts of oxoacids.

  Alternatively, the negative electrode for a lithium ion secondary battery of the present invention is an additive containing a negative electrode active material containing a carbon material capable of occluding and releasing lithium ions and two or more compounds containing different constituents in the general formula (1) And an agent.

（但し、Ｍは、遷移元素、周期表の１２族、１３族、１４族又は１５族元素を表す；Ａ^a+は金属イオン、プロトン又はオニウムイオン、ａは１〜３の整数、ｐはｂ／ａ；ｂは１〜３の整数、ｍは１〜４の整数、ｎは０〜８の整数を表す；Ｒ¹は、−Ｃ（＝Ｏ）−Ｃ（＝Ｏ）−、−Ｃ（＝Ｏ）−Ｒ⁵−Ｃ（＝Ｏ）−、−Ｃ（＝ＮＨ）−Ｃ（＝ＮＨ）−、−Ｃ（＝ＮＨ）−Ｒ⁵−Ｃ（＝ＮＨ）−、−Ｃ（＝Ｓ）−Ｃ（＝Ｓ）、−Ｃ（＝Ｓ）−Ｒ⁵−Ｃ（＝Ｓ）−、−Ｓ（＝Ｏ）−Ｓ（＝Ｏ）−、−Ｓ（＝Ｏ）−Ｒ⁵−Ｓ（＝Ｏ）−を表す；Ｒ⁵は炭素数１〜１０のアルキレン、炭素数１〜１０のハロゲン化アルキレン、炭素数６〜２０のアリーレン又は炭素数６〜２０のハロゲン化アリーレン（これらのアルキレン及びアリーレンはその構造中に置換基、ヘテロ原子を持っていてもよく、またｍが２〜４のときにはｍ個のＲ⁵はそれぞれが結合していてもよい）を表す；Ｒ²は、ハロゲン、炭素数１〜１０のアルキル、炭素数１〜１０のハロゲン化アルキル、炭素数６〜２０のアリール、炭素数６〜２０のハロゲン化アリール（これらのアルキル及びアリールはその構造中に置換基、ヘテロ原子を持っていてもよく、またｎが２〜８のときにはｎ個のＲ²はそれぞれが結合して環を形成してもよい）又は−Ｘ³Ｒ³を表す；Ｘ¹，Ｘ²及びＸ³は、それぞれが独立でＯ，Ｓ又はＮＲ⁴を表す；Ｒ³及びＲ⁴は、それぞれが独立で水素、炭素数１〜１０のアルキル、炭素数１〜１０のハロゲン化アルキル、炭素数６〜２０のアリール、炭素数６〜２０のハロゲン化アリール（これらのアルキル及びアリールはその構造中に置換基、ヘテロ原子を持っていてもよく、Ｒ³又はＲ⁴は複数個存在する場合にはそれぞれが結合して環を形成してもよい）を表す）

(However, M represents a transition element, a group 12, 13, 14, or 15 element of the periodic table; A ^{a +} represents ^a metal ion, proton or onium ion, a represents an integer of 1 to 3, and p represents b / a; b represents an integer of 1 to 3, m represents an integer of 1 to 4, n represents an integer of 0 to 8; R ¹ represents —C (═O) —C (═O) —, —C (= ^{O) -R 5 -C (= O} ) -, - C (= NH) -C (= NH) -, - C (= NH) -R 5 -C (= NH) -, - C (= S) -C (= S), -C (= S) -R < ⁵ > -C (= S)-, -S (= O) -S (= O)-, -S (= O) -R < ⁵ > -S ( ═O) —; R ⁵ is alkylene having 1 to 10 carbons, halogenated alkylene having 1 to 10 carbons, arylene having 6 to 20 carbons or halogenated arylene having 6 to 20 carbons (these alkylene and Arylene is placed in the structure. Each of which may have a substituent, a heteroatom, and when m is 2 to 4, m R ^{5 s} may be bonded to each other); R ² is halogen, having 1 to 10 carbon atoms Alkyl, halogenated alkyl having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, aryl halide having 6 to 20 carbon atoms (these alkyl and aryl may have a substituent or a hetero atom in the structure thereof). And when n is 2 to 8, n R ^{2 s} may be bonded to form a ring) or —X ³ R ³ ; X ¹ , X ² and X ³ are each Independently represents O, S or NR ⁴ ; R ³ and R ⁴ each independently represent hydrogen, alkyl having 1 to 10 carbons, halogenated alkyl having 1 to 10 carbons, aryl having 6 to 20 carbons, Aryl halides having 6 to 20 carbon atoms (these alkyl and Reel substituent group in its structure, may have a hetero atom, R ³ or R ⁴ represents may form a ring) is bonded to each other if there are a plurality)

  The lithium ion secondary battery of the present invention includes a positive electrode having a positive electrode active material, a negative electrode for a lithium ion secondary battery described above, an ion conductive medium that is interposed between the positive electrode and the negative electrode, and conducts lithium ions. , With.

The method for producing a negative electrode for a lithium ion secondary battery of the present invention is as follows.
A negative electrode active material containing a carbon material capable of occluding and releasing lithium ions, a dicarboxylic acid (R _r [C (═O) OH] ₂ ), a dicarboxylic acid amide (R _r [C (═O) NH ₂ ] ₂ ) , Amic acid (R _r [C (═O) OH] [C (═O) NH ₂ ]), dicarboxylic acid imide (R _r [C (OH) (═NH)] ₂ ), bisthiocarboxylic acid (R _r [C (= O) SH] 2), bis dithio carboxylic acid _{(R r [C (= S} ) SH] 2), Jisurufin acid _{(R r [S (= O} ) OH] 2), or their alkali metal Salt (R is alkyl having 1 to 10 carbon atoms, alkyl halide having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, aryl halide having 6 to 20 carbon atoms (these alkyl and aryl are in the structure) And may have a substituent or a hetero atom.) R represents 0 or 1) Oxides, oxoacids, oxoacids of a first compound that is one or more selected from the group consisting of a transition element and one or more elements selected from group 12, group 13, group 14 and group 15 of the periodic table A step of mixing an additive containing one or more second compounds selected from alkali metal salts.

  Or the manufacturing method of the negative electrode for lithium ion secondary batteries of this invention WHEREIN: Two or more types of compounds containing the negative electrode active material containing the carbon material which can occlude / release lithium ion, and a different structural element in General formula (1) And an additive containing.

（但し、Ｍは、遷移元素、周期表の１２族、１３族、１４族又は１５族元素を表す；Ａ^a+は金属イオン、プロトン又はオニウムイオン、ａは１〜３の整数、ｐはｂ／ａ；ｂは１〜３の整数、ｍは１〜４の整数、ｎは０〜８の整数を表す；Ｒ¹は、−Ｃ（＝Ｏ）−Ｃ（＝Ｏ）−、−Ｃ（＝Ｏ）−Ｒ⁵−Ｃ（＝Ｏ）−、−Ｃ（＝ＮＨ）−Ｃ（＝ＮＨ）−、−Ｃ（＝ＮＨ）−Ｒ⁵−Ｃ（＝ＮＨ）−、−Ｃ（＝Ｓ）−Ｃ（＝Ｓ）、−Ｃ（＝Ｓ）−Ｒ⁵−Ｃ（＝Ｓ）−、−Ｓ（＝Ｏ）−Ｓ（＝Ｏ）−、−Ｓ（＝Ｏ）−Ｒ⁵−Ｓ（＝Ｏ）−を表す；Ｒ⁵は炭素数１〜１０のアルキレン、炭素数１〜１０のハロゲン化アルキレン、炭素数６〜２０のアリーレン又は炭素数６〜２０のハロゲン化アリーレン（これらのアルキレン及びアリーレンはその構造中に置換基、ヘテロ原子を持っていてもよく、またｍが２〜４のときにはｍ個のＲ⁵はそれぞれが結合していてもよい）を表す；Ｒ²は、ハロゲン、炭素数１〜１０のアルキル、炭素数１〜１０のハロゲン化アルキル、炭素数６〜２０のアリール、炭素数６〜２０のハロゲン化アリール（これらのアルキル及びアリールはその構造中に置換基、ヘテロ原子を持っていてもよく、またｎが２〜８のときにはｎ個のＲ²はそれぞれが結合して環を形成してもよい）又は−Ｘ³Ｒ³を表す；Ｘ¹，Ｘ²及びＸ³は、それぞれが独立でＯ，Ｓ又はＮＲ⁴を表す；Ｒ³及びＲ⁴は、それぞれが独立で水素、炭素数１〜１０のアルキル、炭素数１〜１０のハロゲン化アルキル、炭素数６〜２０のアリール、炭素数６〜２０のハロゲン化アリール（これらのアルキル及びアリールはその構造中に置換基、ヘテロ原子を持っていてもよく、Ｒ³又はＲ⁴は複数個存在する場合にはそれぞれが結合して環を形成してもよい）を表す）

(However, M represents a transition element, a group 12, 13, 14, or 15 element of the periodic table; A ^{a +} represents ^a metal ion, proton or onium ion, a represents an integer of 1 to 3, and p represents b / a; b represents an integer of 1 to 3, m represents an integer of 1 to 4, n represents an integer of 0 to 8; R ¹ represents —C (═O) —C (═O) —, —C (= ^{O) -R 5 -C (= O} ) -, - C (= NH) -C (= NH) -, - C (= NH) -R 5 -C (= NH) -, - C (= S) -C (= S), -C (= S) -R < ⁵ > -C (= S)-, -S (= O) -S (= O)-, -S (= O) -R < ⁵ > -S ( ═O) —; R ⁵ is alkylene having 1 to 10 carbons, halogenated alkylene having 1 to 10 carbons, arylene having 6 to 20 carbons or halogenated arylene having 6 to 20 carbons (these alkylene and Arylene is placed in the structure. Each of which may have a substituent, a heteroatom, and when m is 2 to 4, m R ^{5 s} may be bonded to each other); R ² is halogen, having 1 to 10 carbon atoms Alkyl, halogenated alkyl having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, aryl halide having 6 to 20 carbon atoms (these alkyl and aryl may have a substituent or a hetero atom in the structure thereof). And when n is 2 to 8, n R ^{2 s} may be bonded to form a ring) or —X ³ R ³ ; X ¹ , X ² and X ³ are each Independently represents O, S or NR ⁴ ; R ³ and R ⁴ each independently represent hydrogen, alkyl having 1 to 10 carbons, halogenated alkyl having 1 to 10 carbons, aryl having 6 to 20 carbons, Aryl halides having 6 to 20 carbon atoms (these alkyl and Reel substituent group in its structure, may have a hetero atom, R ³ or R ⁴ represents may form a ring) is bonded to each other if there are a plurality)

  The negative electrode for lithium ion secondary batteries and the lithium ion secondary battery of the present invention can further suppress an exothermic reaction in a negative electrode active material containing a carbon material. The reason why such an effect is obtained is not clear, but is presumed as follows. For example, it is considered that an additive containing two or more compounds such as the first compound and the second compound described above forms a stable SEI (Solid Electrolyte Interface) film by decomposing on the negative electrode active material during the initial charge. It is done. Here, since the additive containing two or more compounds such as the first compound and the second compound described above and the negative electrode active material are mixed in the negative electrode, a stable film is easily formed. It is presumed that the exothermic reaction of the negative electrode active material can be further suppressed.

Explanatory drawing explaining the component of the compound represented by General formula (1). The schematic diagram which shows an example of the lithium ion secondary battery 10 of this invention. The charging / discharging curve and DSC measurement result of the bipolar cell of Example 1. The charging / discharging curve and DSC measurement result of the bipolar cell of Example 2. The charging / discharging curve and DSC measurement result of the bipolar cell of Example 3. The charging / discharging curve and DSC measurement result of the bipolar cell of Example 4. The charging / discharging curve and DSC measurement result of the bipolar cell of Example 5. The charging / discharging curve and DSC measurement result of the bipolar cell of Example 6. The charging / discharging curve and DSC measurement result of the bipolar cell of the comparative example 1. The charging / discharging curve of the bipolar cell of the comparative example 2 and a DSC measurement result. The charging / discharging curve of the bipolar cell of the comparative example 3, and a DSC measurement result. The charging / discharging curve of the bipolar cell of the comparative example 4, and a DSC measurement result.

  A negative electrode for a lithium ion secondary battery according to the first embodiment of the present invention (hereinafter also referred to as a first negative electrode) includes a negative electrode active material containing a carbon material capable of occluding and releasing lithium, a predetermined first compound, And an additive containing a predetermined second compound. Here, at least before charge / discharge, the first compound and the second compound may be present in the negative electrode.

In the first negative electrode, the first compound described above includes dicarboxylic acid (R _r [C (═O) OH] ₂ ), dicarboxylic acid amide (R _r [C (═O) NH ₂ ] ₂ ), amic acid ( R _r [C (═O) OH] [C (═O) NH ₂ ]), dicarboxylic imide (R _r [C (OH) (═NH)] ₂ ), bisthiocarboxylic acid (R _r [C (= O) SH] _2), bis dithio carboxylic acid _{(R r [C (= S} ) SH] 2), Jisurufin acid _{(R r [S (= O} ) OH] 2), or alkali metal salts thereof. Here, R is one or more selected from alkyl having 1 to 10 carbon atoms, halogenated alkyl having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, and aryl halide having 6 to 20 carbon atoms. These alkyls and aryls may have a substituent or a hetero atom in the structure. Specifically, instead of hydrogen on alkylene and arylene, halogen, chain or cyclic alkyl group, aryl group, alkenyl group, alkoxy group, aryloxy group, sulfonyl group, amino group, cyano group, carbonyl group, acyl It may have a group, an amide group or a hydroxyl group as a substituent, or may have a structure in which nitrogen, sulfur or oxygen is introduced instead of carbon on alkylene and arylene. R represents 0 or 1;

  In the first negative electrode, the second compound described above includes an oxide, an oxo acid, and an oxo acid for one or more elements selected from a transition element and a group 12, group 13, group 14, or group 15 element of the periodic table. 1 or more selected from alkali metal salts of

A negative electrode for a lithium ion secondary battery according to the second embodiment of the present invention (hereinafter also referred to as a second negative electrode) includes a negative electrode active material containing a carbon material capable of occluding and releasing lithium, and a general formula (1) And an additive containing two or more compounds including different constituent elements. Here, two or more kinds of compounds including different constituents in the general formula (1) may be present in the negative electrode at least before charge and discharge. Here, the different component in the general formula (1) may be one element, or may be a combination of adjacent elements. Moreover, it is preferable that a different component is what can comprise General formula (1), when all of them are collected, and it is preferable that each does not overlap. For example, as shown in FIG. 1A, the general formula (1) is changed into a first part including (R ¹ , X ¹ , X ² ) and a second part including (M, R ² , A ^{a +} ). Each may be divided into components. Further, as shown in FIG. 1B, the general formula (1) is converted into a first part including (R ¹ , X ¹ , X ² ), a second part including (M), and (R ² , A ^{a +} ). It is good also as the component which is divided into the 3rd part containing. Further, FIG. 1A illustrates the case where (A ^{a +} ) _p is included in the second portion, but the present invention is not limited to this. For example, (A ^{a +} ) _p may be a single component. However, it may be included in the first part of FIG. Further, in FIG. 1B, the case where (A ^{a +} ) _p is included in the third portion is illustrated, but the present invention is not limited to this, and for example, (A ^{a +} ) _p may be a single component. And it is good also as what is contained in the 1st part and 2nd part of FIG.1 (b).

  In the general formula (1), M is a transition element, a group 12, group 13, group 14 or group 15 element of the periodic table. Among these, it is preferable that it is 1 or more chosen from the nonmetallic element of the 12th group, 13th group, 14th group, and 15th group element of a periodic table, and it is more preferable that they are boron, phosphorus, and silicon. The valence b of the anion is 1 to 3, of which 1 is preferable. The constants m and n are values related to the number of ligands and are determined by the type of M. m is an integer of 1 to 4, and n is an integer of 0 to 8.

Here, R ¹ is —C (═O) —C (═O) —, —C (═O) —R ⁵ —C (═O) —, —C (═NH) —C (═NH). -, - C (= NH) -R 5 -C (= NH) -, - C (= S) -C (= S), - C (= S) -R 5 -C (= S) -, - S (= O) -S (= O) -, - S (= O) -R 5 -S (= O) - represents a. Among, -C (= O) -C ( = O) -, - C (= O) -R 5 -C (= O) - are preferred.

R ⁵ represents alkylene having 1 to 10 carbons, halogenated alkylene having 1 to 10 carbons, arylene having 6 to 20 carbons, or halogenated arylene having 6 to 20 carbons. These alkylene and arylene may have a substituent or a hetero atom in the structure. Specifically, instead of hydrogen on alkylene and arylene, halogen, chain or cyclic alkyl group, aryl group, alkenyl group, alkoxy group, aryloxy group, sulfonyl group, amino group, cyano group, carbonyl group, acyl It may have a group, an amide group or a hydroxyl group as a substituent, or may have a structure in which nitrogen, sulfur or oxygen is introduced instead of carbon on alkylene and arylene. When m is 2 to 4, m R ^{5 s} may be bonded to each other. Examples thereof include a ligand such as ethylenediaminetetraacetic acid.

R ² is halogen, alkyl having 1 to 10 carbon atoms, alkyl halide having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, aryl halide having 6 to 20 carbon atoms, or —X ³ R ³ (X ³ , R ³ will be described later. Alkyl and aryl here may also have a substituent or a hetero atom in the structure in the same manner as R ^5, and when n is 2 to 8, n R ² are bonded to each other to form a ring. May be formed. R ² is preferably an electron-withdrawing group, particularly preferably a fluorine atom. This is because in the case of a fluorine atom, the solubility and dissociation degree of the salt of the anion compound are improved, and the ionic conductivity is improved accordingly. Moreover, it is because oxidation resistance improves and generation | occurrence | production of a side reaction can be suppressed by this.

X ¹ , X ² and X ³ each independently represent O, S or NR ⁴ . That is, the ligand is bonded to M through these heteroatoms.

R ³ and R ⁴ each independently represent hydrogen, an alkyl having 1 to 10 carbon atoms, an alkyl halide having 1 to 10 carbon atoms, an aryl having 6 to 20 carbon atoms, or an aryl halide having 6 to 20 carbon atoms. . These alkyls and aryls may also have a substituent or a hetero atom in the structure in the same manner as R ⁵ . Further, when a plurality of R ³ or R ⁴ are present, they may be bonded to each other to form a ring.

In the cation (A ^{a +} ) of the compound represented by the general formula (1), a is 1 to 3, and p is b / a. Examples of the cation include lithium, sodium, potassium, magnesium, calcium, barium, cesium, rubidium, silver, zinc, copper, cobalt, iron, nickel, manganese, titanium, lead, chromium, vanadium, ruthenium, yttrium, lanthanoid, In addition to cations such as actinides, tetraalkylammonium (wherein alkyl is methyl, ethyl, butyl, etc.), ammonium cations such as triethylammonium, pyridinium, imidazolium, protons, and the like. Among these, a lithium cation, a sodium cation, or a potassium cation is preferable. In particular, in the case of a sodium cation or a potassium cation, a compound containing these may be difficult to dissolve in a non-aqueous electrolyte used in a lithium ion secondary battery and may be difficult to add to the non-aqueous electrolyte. It can be mixed and used.

  The compound represented by the general formula (1) preferably contains one or more anions of PTFO, PFO, PO, BFO, BOB, BMB and BPB represented by the formulas (2) to (8). The reason is that it is easy to form a stable film on the surface of the carbon material contained in the negative electrode active material. A compound containing potassium or sodium as a cation and BOB as an anion is more preferable.

  In the second negative electrode, the additive may include a predetermined first compound and a predetermined second compound as the two or more kinds of compounds described above.

In the second negative electrode, the first compound described above is, for example, the first portion including (R ¹ , X ¹ , X ² ) in FIG. 1A in the general formula (1) or ( R ¹ , X ¹ , X ² ) may be included as a component corresponding to the first part. As such, for example, dicarboxylic acid (R _r [C (═O) OH] ₂ ), dicarboxylic acid amide (R _r [C (═O) NH ₂ ] ₂ ), amic acid (R _r [C (═O) OH] [C (═O) NH ₂ ]), dicarboxylic imide (R _r [C (OH) (═NH)] ₂ ), bisthiocarboxylic acid (R _r [C (═O) SH] ₂ ), bisdithiocarboxylic acid (R _r [C (═S) SH] ₂ ), disulfinic acid (R _r [S (═O) OH] ₂ ), or alkali metal salts thereof can be used. Here, R is one or more selected from alkyl having 1 to 10 carbon atoms, halogenated alkyl having 1 to 10 carbon atoms, aryl having 6 to 20 carbon atoms, and aryl halide having 6 to 20 carbon atoms. These alkyls and aryls may have a substituent or a hetero atom in the structure. Specifically, instead of hydrogen on alkylene and arylene, halogen, chain or cyclic alkyl group, aryl group, alkenyl group, alkoxy group, aryloxy group, sulfonyl group, amino group, cyano group, carbonyl group, acyl It may have a group, an amide group or a hydroxyl group as a substituent, or may have a structure in which nitrogen, sulfur or oxygen is introduced instead of carbon on alkylene and arylene. R represents 0 or 1;

In the second negative electrode, the second compound described above is, for example, the second portion including (M, R ² , A ^{a +} ) in FIG. 1A in the general formula (1) or (M) in FIG. It is good also as a thing containing the component applicable to the 2nd part containing. Examples of such materials include oxides, oxoacids, and alkali metal salts of oxoacids for at least one element selected from transition elements and Group 12, 13, 14, and 15 elements of the periodic table. One or more selected from can be used.

  In the first and second negative electrodes, as the first compound, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, glutaconic acid , Hexenedioic acid, muconic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, anthracene dicarboxylic acid, phenanthrene dicarboxylic acid and other dicarboxylic acids, oxamic acid, malonamic acid, succinamic acid, glutaramic acid, adipamic acid, Maleamic acid, fumaramic acid, phthalamic acid, isophthalamic acid, terephthalamic acid, oxamide, malonamide, succinamide, glutaramide, adipamide, maleamide, fumaramide, phthalamide, isophthalamide, terephthalamide, etc. It is preferably 1 or more selected from a dicarboxylic acid amide. Of these, oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, phthalic acid and the like are more preferable. This is because it is considered that the exothermic reaction of the negative electrode active material can be further suppressed without reducing the proportion of the negative electrode active material that contributes to the charge / discharge reaction as much as possible because the formation number of the SEI film with respect to the addition amount is good with a small number of carbon atoms.

  In the first and second negative electrodes, the second compound is an oxo acid or oxo acid for one or more selected from non-metal elements of Group 12, Group 13, Group 14 and Group 15 elements of the Periodic Table The alkali metal salt is preferably used. Specifically, for example, boric acid, phosphoric acid, silicic acid, lithium borate, lithium phosphate, lithium silicate, sodium borate, sodium phosphate, sodium silicate, potassium borate, potassium phosphate, silicic acid One or more selected from potassium, rubidium borate, rubidium phosphate, rubidium silicate, cesium borate, cesium phosphate, and cesium silicate are preferable. Of these, boric acid, phosphoric acid, silicic acid and the like are preferable. This is because it is considered that a more stable film is easily formed and the exothermic reaction of the negative electrode active material can be further suppressed.

The first and second negative electrodes may further include a predetermined third compound. As the third compound, one or more selected from fluorides of one or more elements selected from Group 1, Group 2, and Group 3 elements of the periodic table, alkyl ammonium fluorides, and ammonium fluorides can be used. Among these, 1 selected from ammonium fluoride, lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride, barium fluoride, and aluminum fluoride The above is preferable. Of these, lithium fluoride, sodium fluoride, and potassium fluoride are more preferable. This is because by including fluorine, the solubility and dissociation degree of the salt of the anion compound are improved, and the ionic conductivity is improved accordingly. Moreover, it is because oxidation resistance improves and generation | occurrence | production of a side reaction can be suppressed by this. Furthermore, if it contains sodium or potassium, it may be difficult to dissolve in the non-aqueous electrolyte used in the lithium ion secondary battery and it may be difficult to add to the non-aqueous electrolyte. It is preferable in that it can be used. In the second negative electrode, the third compound may include, for example, a component corresponding to the third portion including (R ² , A ^{a +} ) in FIG. 1B in the general formula (1). .

  In the first and second negative electrodes, the additive may be all or part of the additive (for example, anions represented by the formulas (2) to (8)) by charging the lithium ion secondary battery at least once. Is decomposed, and the surface of the negative electrode active material is considered to form a film. This coating can be detected by, for example, X-ray photoelectron spectroscopy (XPS) or IR analysis.

  The negative electrode for a lithium ion secondary battery of the present invention was prepared by mixing a negative electrode active material and an additive, adding a suitable solvent to form a paste-like negative electrode mixture, applying and drying on the surface of the current collector, You may compress and form so that an electrode density may be raised as needed. The negative electrode mixture may include other auxiliary materials and conductive materials. Examples of the carbon material contained in the negative electrode active material include cokes, glassy carbons, graphites, non-graphitizable carbons, pyrolytic carbons, and carbon fibers. Of these, graphites such as artificial graphite and natural graphite have an operating potential close to that of metallic lithium, can be charged and discharged at a high operating voltage, and suppresses self-discharge when a lithium salt is used as a supporting salt. In addition, the irreversible capacity during charging can be reduced, which is preferable. The binder plays a role of binding the active material particles. For example, the binder is a fluororesin such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), fluororubber, or heat such as polypropylene or polyethylene. A plastic resin, ethylene-propylene-dienemer (EPDM), sulfonated EPDM, natural butyl rubber (NBR) or the like can be used alone or as a mixture of two or more. In addition, an aqueous dispersion of cellulose or styrene butadiene rubber (SBR), which is an aqueous binder, can also be used. Examples of the solvent for dispersing the negative electrode active material and the binder include N-methylpyrrolidone, dimethylformamide, dimethylacetamide, methyl ethyl ketone, cyclohexanone, methyl acetate, methyl acrylate, diethyltriamine, N, N-dimethylaminopropylamine, and ethylene oxide. An organic solvent such as tetrahydrofuran can be used. Moreover, a dispersing agent, a thickener, etc. may be added to water, and an active material may be slurried with latex, such as SBR. As the thickener, for example, polysaccharides such as carboxymethyl cellulose and methyl cellulose can be used alone or as a mixture of two or more. Examples of the application method include roller coating such as applicator roll, screen coating, doctor blade method, spin coating, bar coater, and the like, and any of these can be used to obtain an arbitrary thickness and shape. Current collectors include copper, nickel, stainless steel, titanium, aluminum, calcined carbon, conductive polymer, conductive glass, Al-Cd alloy, etc., for the purpose of improving adhesion, conductivity and reduction resistance. For example, the surface of copper or the like treated with carbon, nickel, titanium, silver, or the like can also be used. For these, the surface can be oxidized. Examples of the shape of the current collector include foil, film, sheet, net, punched or expanded, lath, porous, foam, and formed fiber group. The thickness of the current collector is, for example, 1 to 500 μm.

  In the negative electrode for a lithium ion secondary battery of the present invention, the weight ratio of the additive to the total amount of the negative electrode active material and the additive is preferably 0.05% by weight or more and 20% by weight or less, preferably 0.1% by weight or more. It is more preferably 15% by weight or less, and further preferably 0.5% by weight or more and 10% by weight or less. Since the said compound is mixed with the negative electrode compound material and a film can be easily formed in a negative electrode active material, the exothermic reaction in a negative electrode active material can be suppressed more with the addition amount of a smaller additive.

  The lithium ion secondary battery of the present invention includes a positive electrode having a positive electrode active material, a negative electrode for a lithium ion secondary battery as described above, and an ion that is interposed between the positive electrode and the negative electrode and conducts lithium ions. A conductive medium.

The positive electrode of the lithium ion secondary battery of the present invention is obtained by mixing a positive electrode active material, a conductive material, and a binder, and adding a suitable solvent to form a paste-like positive electrode mixture. And may be formed by compression to increase the electrode density as necessary. As the positive electrode active material, a sulfide containing a transition metal element, an oxide containing lithium and a transition metal element, or the like can be used. Specifically, transition metal sulfides such as TiS ₂ , TiS ₃ , MoS ₃ and FeS ₂ , Li _(1-x) MnO ₂ (0 <x <1 etc.), Li _(1-x) Mn ₂ O ₄ Lithium manganese composite oxides such as Li _(1-x) CoO ₂ lithium cobalt composite oxides, Li _(1-x) NiO ₂ and other lithium nickel composite oxides, LiV ₂ O ₃ and other lithium vanadium composite oxides And transition metal oxides such as V ₂ O ₅ can be used. Of these, lithium transition metal composite oxides such as LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , and LiV ₂ O ₃ are preferable. The conductive material is not particularly limited as long as it is an electron conductive material that does not adversely affect the battery performance of the positive electrode. For example, graphite such as natural graphite (scale-like graphite, scale-like graphite) or artificial graphite, acetylene black, carbon black, What mixed 1 type (s) or 2 or more types, such as ketjen black, carbon whisker, needle coke, carbon fiber, metal (copper, nickel, aluminum, silver, gold, etc.) can be used. Among these, as the conductive material, carbon black and acetylene black are preferable from the viewpoints of electron conductivity and coatability. Current collectors include aluminum, titanium, stainless steel, nickel, iron, calcined carbon, conductive polymer, conductive glass, and aluminum, copper, etc. for the purpose of improving adhesion, conductivity, and oxidation resistance. A surface treated with carbon, nickel, titanium, silver or the like can be used. For these, the surface can be oxidized. As the binder, the solvent, and the like used for the positive electrode, those exemplified for the negative electrode can be used, respectively, and the same shape as that of the negative electrode can be used for the current collector.

  As an ion conduction medium of the lithium ion secondary battery of the present invention, a non-aqueous electrolyte solution containing a supporting salt, a non-aqueous gel electrolyte solution, or the like can be used. Examples of the solvent for the non-aqueous electrolyte include carbonates, esters, ethers, nitriles, furans, sulfolanes and dioxolanes, and these can be used alone or in combination. Specifically, as carbonates, cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), butylene carbonate, chloroethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC) ), Chain carbonates such as diethyl carbonate (DEC), ethyl-n-butyl carbonate, methyl-t-butyl carbonate, di-i-propyl carbonate, t-butyl-i-propyl carbonate, γ-butyl lactone, γ -Cyclic esters such as valerolactone, chain esters such as methyl formate, methyl acetate, ethyl acetate, methyl butyrate, ethers such as dimethoxyethane, ethoxymethoxyethane, diethoxyethane, acetonitrile Examples include nitriles such as tolyl and benzonitrile, furans such as tetrahydrofuran and methyltetrahydrofuran, sulfolanes such as sulfolane and tetramethylsulfolane, and dioxolanes such as 1,3-dioxolane and methyldioxolane. Among these, the combination of cyclic carbonates and chain carbonates is preferable. According to this combination, not only the cycle characteristics representing the battery characteristics in repeated charge and discharge are excellent, but also the viscosity of the electrolyte, the electric capacity of the obtained battery, the battery output, etc. should be balanced. it can.

The supporting salt contained in the lithium ion secondary battery of the present invention is, for example, LiPF ₆ , LiBF ₄ , LiAsF ₆ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) _{3. , LiSbF 6, LiSiF 6, LiAlF} 4, LiSCN, LiClO 4, LiCl, LiF, LiBr, LiI, and the like LiAlCl _4. Among these, from the group consisting of inorganic salts such as LiPF ₆ , LiBF ₄ , LiAsF ₆ , LiClO ₄ , and organic salts such as LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) _3. It is preferable from the viewpoint of electrical characteristics to use a combination of one or two or more selected salts. The supporting salt preferably has a concentration in the non-aqueous electrolyte of 0.1 mol / L or more and 5 mol / L or less, and more preferably 0.5 mol / L or more and 2 mol / L or less. If the concentration of the supporting salt is 0.1 mol / L or more, a sufficient current density can be obtained, and if it is 5 mol / L or less, the electrolytic solution can be made more stable. Moreover, you may add flame retardants, such as a phosphorus type and a halogen type, to this non-aqueous electrolyte solution.

  Further, instead of the liquid ion conducting medium, a solid ion conducting polymer may be used as the ion conducting medium. As the ion conductive polymer, for example, a polymer gel composed of a polymer such as acrylonitrile, ethylene oxide, propylene oxide, methyl methacrylate, vinyl acetate, vinyl pyrrolidone, and polyvinylidene fluoride and a supporting salt can be used. Further, an ion conductive polymer and a non-aqueous electrolyte can be used in combination. In addition to the ion conductive polymer, an inorganic solid electrolyte, a mixed material of an organic polymer electrolyte and an inorganic solid electrolyte, an inorganic solid powder bound by an organic binder, or the like can be used as the ion conductive medium.

  The lithium ion secondary battery of the present invention may include a separator between the negative electrode and the positive electrode. The separator is not particularly limited as long as the composition can withstand the use range of the lithium ion secondary battery. For example, a polymer nonwoven fabric such as a polypropylene nonwoven fabric or a polyphenylene sulfide nonwoven fabric, or a thin olefin resin such as polyethylene or polypropylene is used. A microporous membrane is mentioned. These may be used alone or in combination.

  The shape of the lithium ion secondary battery of the present invention is not particularly limited, and examples thereof include a coin type, a button type, a sheet type, a laminated type, a cylindrical type, a flat type, and a square type. Moreover, you may apply to the large sized thing etc. which are used for an electric vehicle etc. FIG. 2 is a schematic diagram showing an example of the lithium ion secondary battery 10 of the present invention. The lithium ion secondary battery 10 includes a positive electrode sheet 13 in which a positive electrode active material 12 is formed on a current collector 11, a negative electrode sheet 18 in which a negative electrode active material 17 is formed on the surface of the current collector 14, a positive electrode sheet 13 and a negative electrode The separator 19 provided between the sheet | seat 18 and the non-aqueous electrolyte solution 20 satisfy | filled between the positive electrode sheet | seat 13 and the negative electrode sheet | seat 18 are provided. In this lithium ion secondary battery 10, a separator 19 is sandwiched between a positive electrode sheet 13 and a negative electrode sheet 18, and these are wound and inserted into a cylindrical case 22, and a positive electrode terminal 24 and a negative electrode sheet connected to the positive electrode sheet 13. And a negative electrode terminal 26 connected to each other. Here, the negative electrode sheet 18 contains a mixture of a negative electrode active material containing a carbon material and an additive containing two or more predetermined compounds such as the first compound and the second compound described above.

  The first negative electrode manufacturing method of the present invention includes a step of mixing a negative electrode active material containing a carbon material capable of occluding and releasing lithium and an additive containing a predetermined first compound and a predetermined second compound. Is included. Here, as a 1st compound and a 2nd compound, what was demonstrated by the 1st negative electrode mentioned above can be used suitably.

  The second negative electrode manufacturing method of the present invention includes a negative electrode active material containing a carbon material capable of occluding and releasing lithium, and an additive containing two or more compounds containing different constituents in the general formula (1), The process of mixing is included. Here, as the additive containing two or more compounds including different constituents in the general formula (1), those described in the second negative electrode described above can be used as appropriate.

  In both the first and second negative electrode manufacturing methods of the present invention, various aspects shown in the description of the negative electrode for a lithium ion secondary battery described above can be adopted. For example, when the additive and the negative electrode active material are mixed, an additive including the third compound described above may be used, and the weight ratio of the additive to the total amount of the negative electrode active material and the additive is 0.05. It is good also as a weight% or more and 20 weight% or less.

  In the method for producing a negative electrode for a lithium ion secondary battery, a lithium ion secondary battery, and a negative electrode for a lithium ion secondary battery according to the present invention described in detail above, a predetermined two or more kinds such as the first compound and the second compound described above are used. Since the additive containing the compound and the negative electrode active material are mixed and present in the negative electrode, a stable film is easily formed by the additive, and the exothermic reaction of the negative electrode active material can be further suppressed by this film. For this reason, a more stable and safe lithium ion secondary battery can be provided.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  Below, the example which produced the lithium ion secondary battery of this invention concretely is demonstrated as an Example.

[Examples 1 to 6]
A mixture was obtained by mixing 95% by weight of artificial graphite as a negative electrode active material and 5% by weight of polyvinylidene fluoride as a binder. 90% by weight of this mixture and 10% by weight of a mixture of boric acid and oxalic acid mixed at a molar ratio of 1: 2 as an additive were mixed and pellet-molded to obtain a negative electrode mixture. LiPF ₆ was dissolved in a carbonate mixed solvent in which EC, DMC, and EMC were mixed at a volume ratio of 3: 4: 3 as a non-aqueous electrolyte so that LiPF ₆ would be 1 mol / L using lithium metal as a counter electrode. A bipolar cell was produced using the prepared one. This was designated Example 1. In Example 1, oxalic acid as the first compound includes the first part of FIG. 1A, and boric acid as the second compound includes the second part of FIG. ) Consists of protons as a cation and BOB (see formula (6)). A bipolar cell obtained through the same steps as in Example 1 was used as Example 2 except that boric acid and malonic acid were mixed at a molar ratio of 1: 2 as an additive. In Example 2, malonic acid as the first compound includes the first part of FIG. 1A, and boric acid as the second compound includes the second part of FIG. ) Consists of protons as cations and BMB (see formula (7)). A bipolar cell obtained through the same steps as in Example 1 was used as Example 3 except that a mixture of boric acid and phthalic acid in a molar ratio of 1: 2 was used as an additive. In Example 3, phthalic acid as the first compound includes the first part of FIG. 1A and boric acid as the second compound includes the second part of FIG. ) Consists of a proton as a cation and BPB (see formula (8)). Moreover, the bipolar cell obtained through the process similar to Example 1 except having used what mixed sodium fluoride, boric acid, and oxalic acid in the molar ratio of 2: 1: 1 as an additive. Was taken as Example 4. In Example 4, oxalic acid, which is the first compound, is the first part of FIG. 1B, and boric acid, which is the second compound, is the second part of FIG. Sodium includes the third part of FIG. 1B, and the general formula (1) is composed of sodium ions as a cation and BFO (see formula (5)). In addition, Example 5 was a bipolar cell obtained through the same steps as Example 1 except that phosphoric acid and oxalic acid were mixed at a molar ratio of 1: 3 as an additive. In Example 5, oxalic acid, which is the first compound, includes the first part in FIG. 1A, and phosphoric acid, which is the second compound, includes the second part in FIG. ) Consists of protons as cations and PO (see formula (4)). Moreover, the bipolar cell obtained through the process similar to Example 1 except having used what mixed lithium fluoride, phosphoric acid, and oxalic acid by the molar ratio of 2: 1: 2 as an additive. Was taken as Example 6. In Example 6, oxalic acid, which is the first compound, is the first part of FIG. 1 (b), and boric acid, which is the second compound, is the second part of FIG. Sodium includes the third part of FIG. 1B, and the general formula (1) is composed of lithium ions as a cation and PFO (see formula (3)).

[Comparative Examples 1-4]
A bipolar cell obtained through the same steps as in Example 1 was used as Comparative Example 1 except that no additive was used. Moreover, the bipolar cell obtained through the process similar to Example 1 was used as the comparative example 2 except having used only boric acid as an additive. Moreover, the bipolar cell obtained through the process similar to Example 1 was used as the comparative example 3 except having used only oxalic acid as an additive. Moreover, the bipolar cell obtained through the process similar to Example 1 was made into the comparative example 4 except having used only lithium oxalate as an additive.

(Evaluation of bipolar cell)
The produced bipolar cell was discharged under a temperature condition of 20 ° C. with a constant current of a current density of 70 μA / cm ^{2 to} a lower limit voltage of 0.01 V, and then with a constant current of a current density of 70 μA / cm ² and an upper limit voltage of 1 The battery was charged to 2V. The value obtained by dividing the initial discharge capacity per unit active material by the initial charge capacity per unit active material and multiplying by 100 was defined as the charge / discharge efficiency. Further, the exothermic reaction between the negative electrode after discharge again and the non-aqueous electrolyte solution was estimated by differential scanning calorimetry (DSC). Evaluation was performed by the presence or absence of the heat_generation | fever in 100 to 150 degreeC vicinity.

(Results and discussion)
Table 1 summarizes the additives of Examples 1 to 6 and Comparative Examples 1 to 4 and the exothermic heat of DSC. 3 to 12 are the charge / discharge curves and DSC measurement results of Examples 1 to 6 and Comparative Examples 1 to 4, respectively. As shown in Table 1 and FIGS. 3 to 12, only one of the first compound and the second compound described above and the first compound and the second compound described above in which the first compound and the second compound described above are not added to the negative electrode mixture at all. In Comparative Examples 2 to 4 where no addition was made, heat generation was observed at around 100 ° C to 150 ° C. On the other hand, in Examples 1 to 6 in which the first compound and the second compound described above were added to the negative electrode mixture, no heat generation was observed in the vicinity of 100 ° C. to 150 ° C. It was found that the exothermic reaction was suppressed. Suppressing heat generation in this temperature range is more preferable because it can prevent a chain of exothermic reactions. Thus, in the negative electrode to which both the first compound and the second compound described above are added, the decomposition and formation of the coating of the first compound and the second compound proceed efficiently in the charge / discharge process, and the negative electrode, the electrolyte solution, It was found that the exothermic reaction was suppressed. Here, the maximum value of 0.25 W · g ⁻¹ or less was regarded as no heat generation.

  DESCRIPTION OF SYMBOLS 10 Lithium ion secondary battery, 11 Current collector, 12 Positive electrode active material, 13 Positive electrode sheet, 14 Current collector, 17 Negative electrode active material, 18 Negative electrode sheet, 19 Separator, 20 Nonaqueous electrolyte, 22 Cylindrical case, 24 Positive electrode Terminal, 26 Negative terminal.

Claims (6)

A negative electrode active material containing a carbon material capable of inserting and extracting lithium;
Oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, glutaconic acid, hexenedioic acid, muconic acid, phthalic acid, isophthalic acid, terephthalic acid Acid, naphthalene dicarboxylic acid, anthracene dicarboxylic acid, phenanthrene dicarboxylic acid, oxamic acid, malonamic acid, succinamic acid, glutaric acid, adipamic acid, maleamic acid, fumaramic acid, phthalamic acid, isophthalamic acid, terephthalamic acid, oxamide, malonamide , succinamide, glutaramide, Ajipuamido, maleamic, fumaramide, phthalamide, isophthalamide, a first compound is one or more selected from terephthalamide, boric acid, phosphoric acid, silicic acid, lithium borate Lithium phosphate, lithium silicate, sodium borate, sodium phosphate, sodium silicate, potassium borate, potassium phosphate, potassium silicate, rubidium borate, rubidium phosphate, rubidium silicate, cesium borate, An additive comprising one or more second compounds selected from cesium phosphate and cesium silicate ;
And a negative electrode for a lithium ion secondary battery. It contains a third compound that is one or more selected from a fluoride of one or more elements selected from Group 1, Group 2, and Group 3 elements of the periodic table, alkylammonium fluoride, and ammonium fluoride. 2. The negative electrode for a lithium ion secondary battery according to 1 . The third compound is selected from ammonium fluoride, lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride, barium fluoride, and aluminum fluoride. One or more selected,
The negative electrode for lithium ion secondary batteries according to claim 2 . The weight ratio of the additive to the total amount of the negative electrode active material and the additive is 0.05 wt% or more and 20 wt% or less,
The negative electrode for a lithium ion secondary battery according to any one of claims 1 to 3 . A positive electrode having a positive electrode active material;
The negative electrode for a lithium ion secondary battery according to any one of claims 1 to 4 ,
An ion conductive medium interposed between the positive electrode and the negative electrode and conducting lithium ions;
Lithium ion secondary battery equipped with. Anode active materials containing carbon materials capable of occluding and releasing lithium ions, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, Glutaconic acid, hexenedioic acid, muconic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, anthracene dicarboxylic acid, phenanthrene dicarboxylic acid, oxamic acid, malonamic acid, succinamic acid, glutamic acid, adipamic acid, maleamic acid, fumaramide acid, phthalamate, isophthalamide acid, terephthalamide acid, selected oxamide, malonamide, succinamide, glutaramide, Ajipuamido, maleamic, fumaramide, phthalamide, isophthalamide, from terephthalamide In the first compound is higher, boric acid, phosphoric acid, silicic acid, lithium borate, lithium phosphate, lithium silicate, sodium borate, sodium phosphate, sodium silicate, potassium borate, potassium phosphate, silicate A step of mixing an additive containing at least one second compound selected from potassium acid, rubidium borate, rubidium phosphate, rubidium silicate, cesium borate, cesium phosphate, and cesium silicate , A method for producing a negative electrode for a lithium ion secondary battery.

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