JP2002056889A - Electrolyte for battery - Google Patents
Electrolyte for batteryInfo
- Publication number
- JP2002056889A JP2002056889A JP2000241655A JP2000241655A JP2002056889A JP 2002056889 A JP2002056889 A JP 2002056889A JP 2000241655 A JP2000241655 A JP 2000241655A JP 2000241655 A JP2000241655 A JP 2000241655A JP 2002056889 A JP2002056889 A JP 2002056889A
- Authority
- JP
- Japan
- Prior art keywords
- electrolyte
- organic solvent
- battery
- electrolytic solution
- phosphorus compound
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、電池用の電解液、
特にリチウム電池等の二次電池に適した電解液に関す
る。TECHNICAL FIELD The present invention relates to an electrolyte for a battery,
Particularly, the present invention relates to an electrolytic solution suitable for a secondary battery such as a lithium battery.
【０００２】[0002]
【従来の技術】非水電解液を使用した二次電池は、高出
力電圧と大放電容量を有し、しかも貯蔵安定性に優れて
いるために、各種の電気機器、特にノート型パソコン、
ハンディビデオカメラ、携帯電話等の携帯用の電気機器
に広く使用されている。2. Description of the Related Art A secondary battery using a non-aqueous electrolyte has a high output voltage, a large discharge capacity, and excellent storage stability.
It is widely used in portable electric devices such as handy video cameras and mobile phones.
【０００３】かかる二次電池の電解液は、有機溶媒に電
解質を溶解した液が使用されており、有機溶媒として
は、電気化学的特性に優れている点を考慮してエチレン
カーボネート（ＥＣ）を主成分とし、低粘度化のために
ジエチルカーボネート（ＤＥＣ）等の低粘度溶媒が添加
されている。ＤＥＣ等の低粘度溶媒は引火点が室温付近
にある可燃性の化合物であるため、使用中の電池の温度
上昇により有機溶媒の蒸気圧が上昇して可燃性の有機溶
媒が漏洩して引火するおそれがある。かかる有機溶媒の
漏洩を防止すると共に電圧の低下を防止するために、通
常、二次電池においては金属ケース等の高剛性のケース
が使用されている。As an electrolyte for such a secondary battery, a solution obtained by dissolving an electrolyte in an organic solvent is used. As the organic solvent, ethylene carbonate (EC) is used in consideration of its excellent electrochemical characteristics. As a main component, a low-viscosity solvent such as diethyl carbonate (DEC) is added for lowering the viscosity. Since a low-viscosity solvent such as DEC is a flammable compound having a flash point near room temperature, the vapor pressure of the organic solvent increases due to an increase in the battery temperature during use, and the flammable organic solvent leaks and ignites. There is a risk. In order to prevent such leakage of the organic solvent and to prevent a voltage drop, a highly rigid case such as a metal case is usually used in a secondary battery.
【０００４】[0004]
【発明が解決しようとする課題】しかし、電気機器にお
いて電気素子が暴走したときには急激に電池の温度上昇
が起こり、有機溶媒の蒸気圧が急速に高まる場合があ
る。このような場合に有機溶媒の漏洩を防止するために
は、ケースを厚くして電池の耐圧性を高くする方法が考
えられるが、電池重量が大きくなると共にコストが高く
なり、好ましいものではない。However, when an electric element runs away in an electric device, the temperature of the battery rapidly rises, and the vapor pressure of the organic solvent may increase rapidly. In such a case, in order to prevent the leakage of the organic solvent, a method of increasing the pressure resistance of the battery by increasing the thickness of the case may be considered, but this is not preferable because the battery weight increases and the cost increases.
【０００５】電池温度が急激に高まった場合の有機溶媒
の上記の電池内の圧力上昇、有機溶媒の漏洩を防止する
方法として、電解液にポリフッ化ビニリデンの粉末を添
加する方法が公知である（２０００ バッテリー技術シ
ンポジウムＳＥＳＳＩＯＮ３要旨集第５頁）。[0005] As a method for preventing the above-mentioned pressure rise of the organic solvent in the battery and leakage of the organic solvent when the battery temperature is rapidly increased, a method of adding polyvinylidene fluoride powder to an electrolyte is known ( 2000 Battery Technology Symposium SESSION 3 Abstracts, p. 5).
【０００６】しかし、ポリフッ化ビニリデンの融点は１
６０℃と高く、かなり電池が高温にならないとその効果
が十分に発揮されず、またポリフッ化ビニリデン粉末自
体が高価であるためにこれを使用した二次電池も高価な
ものとなってしまうという問題がある。However, the melting point of polyvinylidene fluoride is 1
The problem is that the effect is not sufficiently exhibited unless the temperature of the battery is extremely high, such as 60 ° C., and the polyvinylidene fluoride powder itself is expensive, so that the secondary battery using the same is also expensive. There is.
【０００７】本発明の目的は、比較的低い温度上昇でも
有機溶媒の蒸気圧上昇抑制効果が高く、低コストの電池
用電解液を提供することにある。An object of the present invention is to provide a low-cost battery electrolyte which has a high effect of suppressing an increase in vapor pressure of an organic solvent even at a relatively low temperature rise.
【０００８】[0008]
【課題を解決するための手段】本発明者らは、上記目的
を達成すべく、ＤＥＣを含むＥＣの温度上昇に伴う重量
減少、即ち蒸気圧上昇の抑制について鋭意研究したとこ
ろ、特定のリン化合物の添加により有効にＤＥＣ等の揮
発による電解液の重量減少を防止できることを見出し、
本発明を完成するに至った。Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies on the reduction of the weight, that is, the suppression of the increase in the vapor pressure, of ECs including DECs. It was found that the addition of N can effectively prevent a decrease in the weight of the electrolytic solution due to volatilization of DEC or the like,
The present invention has been completed.
【０００９】本発明の電池用電解液は、有機溶媒、電解
質及び融点が７０〜１５０℃のリン化合物微粒子を含む
液状の電解液であることを特徴とする。The battery electrolyte of the present invention is a liquid electrolyte containing an organic solvent, an electrolyte and phosphorus compound fine particles having a melting point of 70 to 150 ° C.
【００１０】融点が７０〜１５０℃のリン化合物微粒子
を電解液に添加することにより、温度上昇による電解液
中の有機溶媒の重量減少が効果的に抑制でき、その結
果、電池の内圧の上昇、有機溶媒の漏洩が防止可能とな
った。またリン化合物はポリフッ化ビニリデン等と比較
して低価格であるために電解液の低コスト化の要請をも
満たすものとなった。[0010] By adding phosphorus compound fine particles having a melting point of 70 to 150 ° C to the electrolytic solution, a decrease in the weight of the organic solvent in the electrolytic solution due to a rise in temperature can be effectively suppressed. The leakage of the organic solvent can be prevented. Further, since the phosphorus compound is inexpensive as compared with polyvinylidene fluoride or the like, it meets the demand for reducing the cost of the electrolytic solution.
【００１１】使用するリン化合物微粒子の融点は、８０
〜１３０℃であることがより好ましい。The melting point of the phosphorus compound fine particles used is 80
It is more preferable that the temperature is 130 ° C.
【００１２】前記リン化合物微粒子の添加量が電解液全
量中０．５〜５重量％であることが好ましい。It is preferable that the amount of the phosphorus compound fine particles is 0.5 to 5% by weight based on the total amount of the electrolytic solution.
【００１３】リン化合物微粒子の添加量が０．５重量％
未満の場合には添加による効果が小さく、従って温度上
昇による電解液中の有機溶媒の重量減少の抑制効果が十
分ではなく、５重量％以上添加すると電解液の流動性が
低下し、これを使用した電池の特性が好ましいものでは
なくなる場合がある。The amount of the phosphorus compound fine particles added is 0.5% by weight.
If the amount is less than 10%, the effect of the addition is small. Therefore, the effect of suppressing the decrease in the weight of the organic solvent in the electrolytic solution due to the temperature rise is not sufficient. In some cases, the characteristics of the obtained battery may not be favorable.
【００１４】[0014]
【発明の実施の形態】上述の電解質を溶解して電解液と
するための有機溶媒は、カーボネート化合物の少なくと
も１種が使用される。カーボネート化合物としては、具
体的にはエチレンカーボネート、プロピレンカーボネー
ト等の高誘電率溶媒と、ジエチルカーボネート、エチル
メチルカーボネート、１，２−ジメトキシエタン、２−
メチルテトラヒドロフラン等の低粘度溶剤との組合せが
電解質、特にリチウム化合物の溶解性、伝導度の高さが
優れており、好適なものとして例示される。DETAILED DESCRIPTION OF THE INVENTION At least one carbonate compound is used as an organic solvent for dissolving the above-mentioned electrolyte into an electrolyte. Specific examples of the carbonate compound include a high dielectric constant solvent such as ethylene carbonate and propylene carbonate, and diethyl carbonate, ethyl methyl carbonate, 1,2-dimethoxyethane, and 2-carbonate.
A combination with a low-viscosity solvent such as methyltetrahydrofuran is excellent in solubility and conductivity of an electrolyte, particularly a lithium compound, and is exemplified as a preferable one.
【００１５】上記の有機溶媒に加えて、伝導度を低下さ
せない範囲で他の溶剤を添加することも好ましい。添加
可能な溶剤としては、カーボネート化合物と相溶性のよ
い化合物が使用され、具体的にはジオキサン、ジエチレ
ングリコールジメチルエーテル、ジオキソラン等のエー
テル化合物、ε−カプロラクトン、γ−ブチロラクトン
等のラクトン化合物、ジメチルホルムアミド、ジメチル
アセトアミド等のアミド化合物等が例示される。[0015] In addition to the above organic solvent, it is also preferable to add another solvent as long as the conductivity is not reduced. As the solvent that can be added, a compound having good compatibility with a carbonate compound is used. Examples include amide compounds such as acetamide.
【００１６】本発明の電解液に使用する電解質として
は、リチウム化合物の使用が好ましく、公知のリチウム
イオン化合物が限定なく使用可能である。具体的にはＬ
ｉＡｓＦ6 ，ＬｉＳｂＦ6 ，ＬｉＢＦ4 ，ＬｉＣｌＯ
4 ，ＬｉＩ，ＬｉＣｌ，ＬｉＡｌＣｌ4 ，ＬｉＨＦ2 ，
ＬｉＳＣＮ，ＬｉＳＯ3 ＣＦ3 ，ＬｉＰＦ6 等のＬｉ化
合物から選択される少なくとも１種が使用される。これ
らの化合物は、使用する溶剤への溶解度、電解液の伝導
度等を考慮して適宜選択して使用され、その濃度は特に
限定されるものではないが、０．５ｍｏｌ／Ｌ〜１．５
ｍｏｌ／Ｌであることが好ましい。As the electrolyte used in the electrolytic solution of the present invention, use of a lithium compound is preferable, and known lithium ion compounds can be used without limitation. Specifically, L
iAsF 6 , LiSbF 6 , LiBF 4 , LiClO
4, LiI, LiCl, LiAlCl 4 , LiHF 2,
At least one selected from Li compounds such as LiSCN, LiSO 3 CF 3 and LiPF 6 is used. These compounds are appropriately selected and used in consideration of the solubility in the solvent to be used, the conductivity of the electrolytic solution, and the like, and the concentration thereof is not particularly limited, but is 0.5 mol / L to 1.5 mol / L.
It is preferably mol / L.
【００１７】リン化合物微粒子を構成するリン化合物
は、融点が７０〜１５０℃、より好ましくは８０〜１３
０℃の化合物を使用する。このようなリン化合物として
は、具体的には、トリフェニルホスフィン等のホスフィ
ン類、縮合リン酸エステル類、リン含有ポリカーボネー
ト類等が例示される。これらのリン化合物は単独で使用
してもよく、２種以上を併用してもよい。リン化合物微
粒子は電解液の温度上昇により溶融するが、その際、有
機溶媒に溶解しても、また溶解しなくてもよいが、冷却
されて温度が低下すると微粒子状に析出するものである
ことが好ましい。溶解しないものは電解液温度の低下に
より、再び微粒子状に固化する。The phosphorus compound constituting the fine particles of the phosphorus compound has a melting point of 70 to 150 ° C., more preferably 80 to 13 ° C.
The compound at 0 ° C. is used. Specific examples of such a phosphorus compound include phosphines such as triphenylphosphine, condensed phosphates, and phosphorus-containing polycarbonates. These phosphorus compounds may be used alone or in combination of two or more. Phosphorus compound fine particles are melted by the temperature rise of the electrolytic solution, and may be dissolved in an organic solvent or may not be dissolved at that time, but should precipitate in the form of fine particles when the temperature is lowered by cooling. Is preferred. Those that do not dissolve solidify again into fine particles due to a decrease in the temperature of the electrolytic solution.
【００１８】本発明の電解液は、リチウム二次電池等の
公知の二次電池に使用可能である。二次電池は、基本的
には正極及び負極と、それらの電極の間に介在する電解
液と、これらを収容する電槽とから構成される。その電
極構造（積層構造）については特に限定されるものでは
なく、公知の電極構造とすることができる。例えば、正
極及び負極ともに平板状の電極板を用い、それらの間に
同じく平板状のセパレータを介在させて積層したものが
例示される。この電極構造を有する電池には、コイン型
電池や、角型電池等がある。また、正極及び負極ともに
帯状の電極板を用い、それらの間にセパレータを介在さ
せて略円柱状に巻回してなるものも例示される。The electrolytic solution of the present invention can be used for a known secondary battery such as a lithium secondary battery. A secondary battery basically includes a positive electrode and a negative electrode, an electrolytic solution interposed between the electrodes, and a battery case for accommodating them. The electrode structure (laminated structure) is not particularly limited, and may be a known electrode structure. For example, there is exemplified a configuration in which a flat electrode plate is used for both the positive electrode and the negative electrode, and the same plate-like separator is interposed between them. Batteries having this electrode structure include coin-type batteries and prismatic batteries. In addition, there is also exemplified a case in which a strip-shaped electrode plate is used for both the positive electrode and the negative electrode, and a separator is interposed therebetween and is wound in a substantially columnar shape.
【００１９】[0019]
【実施例】以下、本発明の構成と効果を具体的に示す実
施例等について説明する。有機溶媒としてエチレンカー
ボネート（ＥＣ）とジエチレンカーボネート（ＤＥＣ）
をＥＣ／ＤＥＣ＝３／７（重量比）にて混合した混合溶
剤を使用し、電解質としてＬｉＰＦ6 を１ｍｏｌ／Ｌと
なるように溶解して電解液とし、これにリン化合物微粒
子として縮合リン酸エステル微粒子ＰＸ−２００（融点
９７−９８℃、大八化学工業製）を有機溶媒に対して１
重量％となる量を添加、分散して実施例の電解液とし
た。比較例として、リン化合物微粉末を添加しない電解
液を準備した。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and the like specifically showing the configuration and effects of the present invention will be described below. Ethylene carbonate (EC) and diethylene carbonate (DEC) as organic solvents
Was mixed with EC / DEC = 3/7 (weight ratio), and LiPF 6 was dissolved as an electrolyte so as to have a concentration of 1 mol / L to obtain an electrolytic solution. Ester fine particles PX-200 (melting point 97-98 ° C, manufactured by Daihachi Chemical Industry)
The resulting solution was added and dispersed in an amount of weight% to obtain the electrolyte solution of the example. As a comparative example, an electrolytic solution to which no phosphorus compound fine powder was added was prepared.
【００２０】実施例電解液のイオン伝導度を測定したと
ころ、２．０×１０-2Ｓ／ｃｍであり、比較例の電解液
のイオン伝導度と同じであった。The ionic conductivity of the electrolytic solution of the example was measured to be 2.0 × 10 −2 S / cm, which was the same as the ionic conductivity of the electrolytic solution of the comparative example.
【００２１】実施例、比較例のそれぞれの電解液につい
て、熱質量損失を測定した。測定は、熱重量分析装置２
０００型２９５０高分解能オートＴＧＡ（ＴＡインスツ
ルメント社製）を使用し、昇温速度１０℃／分にて行っ
た。測定結果を図１に示した。The thermal mass loss was measured for each of the electrolyte solutions of the example and the comparative example. The measurement was performed using a thermogravimetric analyzer 2
Using a 000 type 2950 high resolution auto TGA (manufactured by TA Instruments), the temperature was raised at a rate of 10 ° C./min. The measurement results are shown in FIG.
【００２２】この結果より、リン化合物微粉末を含む実
施例の電解液の重量減少は、同じ重量減少率において比
較例と比べると１０〜１５℃高温側にシフトしており、
有機溶媒の揮発を効果的に抑制していることが分かる。From these results, the weight loss of the electrolyte solution of the example containing the phosphorus compound fine powder was shifted to the high temperature side of 10 to 15 ° C. as compared with the comparative example at the same weight reduction rate.
It can be seen that the volatilization of the organic solvent is effectively suppressed.
【図１】加熱による電解液の重量減少率の測定結果を示
したグラフFIG. 1 is a graph showing a measurement result of a weight reduction rate of an electrolytic solution by heating.
Claims (2)
０℃のリン化合物微粒子を含む液状の電池用電解液。1. An organic solvent, an electrolyte and a melting point of 70 to 15.
A liquid battery electrolyte containing 0 ° C. phosphorus compound fine particles.
全量中０．５〜５重量％である請求項１に記載の電池用
電解液。2. The battery electrolyte according to claim 1, wherein the amount of the phosphorus compound fine particles is 0.5 to 5% by weight based on the total weight of the electrolyte.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000241655A JP2002056889A (en) | 2000-08-09 | 2000-08-09 | Electrolyte for battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000241655A JP2002056889A (en) | 2000-08-09 | 2000-08-09 | Electrolyte for battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2002056889A true JP2002056889A (en) | 2002-02-22 |
Family
ID=18732815
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000241655A Withdrawn JP2002056889A (en) | 2000-08-09 | 2000-08-09 | Electrolyte for battery |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2002056889A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007521625A (en) * | 2003-12-30 | 2007-08-02 | チェイル インダストリーズ インコーポレイテッド | Non-aqueous electrolyte for batteries |
| JPWO2014119249A1 (en) * | 2013-01-31 | 2017-01-26 | 三洋電機株式会社 | Positive electrode for non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery |
| CN109003835A (en) * | 2018-08-09 | 2018-12-14 | 上海奥威科技开发有限公司 | A kind of electrolyte, preparation method and lithium ion battery and lithium-ion capacitor |
| JP2019003799A (en) * | 2017-06-14 | 2019-01-10 | 三菱ケミカル株式会社 | Nonaqueous electrolyte and nonaqueous electrolyte secondary battery |
| JP2019046733A (en) * | 2017-09-06 | 2019-03-22 | トヨタ自動車株式会社 | Nonaqueous electrolyte secondary battery |
-
2000
- 2000-08-09 JP JP2000241655A patent/JP2002056889A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007521625A (en) * | 2003-12-30 | 2007-08-02 | チェイル インダストリーズ インコーポレイテッド | Non-aqueous electrolyte for batteries |
| JPWO2014119249A1 (en) * | 2013-01-31 | 2017-01-26 | 三洋電機株式会社 | Positive electrode for non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery |
| JP2019003799A (en) * | 2017-06-14 | 2019-01-10 | 三菱ケミカル株式会社 | Nonaqueous electrolyte and nonaqueous electrolyte secondary battery |
| JP2019046733A (en) * | 2017-09-06 | 2019-03-22 | トヨタ自動車株式会社 | Nonaqueous electrolyte secondary battery |
| CN109003835A (en) * | 2018-08-09 | 2018-12-14 | 上海奥威科技开发有限公司 | A kind of electrolyte, preparation method and lithium ion battery and lithium-ion capacitor |
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