JP7001964B2 - How to manufacture a separator for a secondary battery - Google Patents
How to manufacture a separator for a secondary battery Download PDFInfo
- Publication number
- JP7001964B2 JP7001964B2 JP2018222500A JP2018222500A JP7001964B2 JP 7001964 B2 JP7001964 B2 JP 7001964B2 JP 2018222500 A JP2018222500 A JP 2018222500A JP 2018222500 A JP2018222500 A JP 2018222500A JP 7001964 B2 JP7001964 B2 JP 7001964B2
- Authority
- JP
- Japan
- Prior art keywords
- separator
- secondary battery
- pva
- emulsion
- silicone
- 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.)
- Active
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 20
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 36
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 36
- 239000000839 emulsion Substances 0.000 claims description 33
- 238000000034 method Methods 0.000 claims description 25
- 239000002270 dispersing agent Substances 0.000 claims description 21
- 229920001296 polysiloxane Polymers 0.000 claims description 17
- 239000007788 liquid Substances 0.000 claims description 13
- 239000003960 organic solvent Substances 0.000 claims description 11
- 239000011148 porous material Substances 0.000 description 19
- 239000007864 aqueous solution Substances 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 239000002245 particle Substances 0.000 description 9
- 239000000243 solution Substances 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 8
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 7
- 229910001416 lithium ion Inorganic materials 0.000 description 7
- 239000012528 membrane Substances 0.000 description 6
- 239000002904 solvent Substances 0.000 description 6
- 238000001035 drying Methods 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- RUOJZAUFBMNUDX-UHFFFAOYSA-N propylene carbonate Chemical compound CC1COC(=O)O1 RUOJZAUFBMNUDX-UHFFFAOYSA-N 0.000 description 5
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 239000011259 mixed solution Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- KPUWHANPEXNPJT-UHFFFAOYSA-N disiloxane Chemical class [SiH3]O[SiH3] KPUWHANPEXNPJT-UHFFFAOYSA-N 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- 229920003169 water-soluble polymer Polymers 0.000 description 3
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 description 2
- 239000002800 charge carrier Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 229910001415 sodium ion Inorganic materials 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 229910002808 Si–O–Si Inorganic materials 0.000 description 1
- 239000011149 active material Substances 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000013626 chemical specie Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 239000007773 negative electrode material Substances 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
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
Landscapes
- Cell Separators (AREA)
- Electric Double-Layer Capacitors Or The Like (AREA)
Description
本発明は、二次電池のセパレータに関する。また、本発明は、二次電池に備えられたセパレータの製造方法に関する。 The present invention relates to a separator for a secondary battery. The present invention also relates to a method for manufacturing a separator provided in a secondary battery.
比較的高い出力と高い容量が実現できるリチウムイオン二次電池等の二次電池は、電気を駆動源とする車両搭載用電源、あるいはパソコンおよび携帯端末等の電気製品等に搭載される電源として重要である。特に、軽量で高エネルギー密度が得られるリチウムイオン二次電池は、電気自動車（ＥＶ）、プラグインハイブリッド自動車（ＰＨＶ）、ハイブリッド自動車（ＨＶ）等の車両の駆動用高出力電源として好ましく、今後ますます需要が拡大することが予想される。 Secondary batteries such as lithium-ion secondary batteries that can achieve relatively high output and high capacity are important as power sources for vehicles mounted on electricity as a drive source, or as power sources installed in electric products such as personal computers and mobile terminals. Is. In particular, lithium-ion secondary batteries, which are lightweight and have high energy density, are preferable as high-output power sources for driving vehicles such as electric vehicles (EV), plug-in hybrid vehicles (PHV), and hybrid vehicles (HV). Demand is expected to grow more and more.
この種の二次電池（以下、単に「電池」ともいう。）の一つの典型的な構成では、電極集電体の表面に電荷担体となり得る化学種を可逆的に吸蔵および放出し得る電極活物質層（具体的には、正極活物質層および負極活物質層）を備える正負の電極が、多孔質膜からなるセパレータを介在させつつ交互に積層されている。かかる正負極間に介在するセパレータは、正負極間の短絡を防止し、かつ、電解質を含浸して伝導パス（導電経路）として機能し得る。 In one typical configuration of this type of secondary battery (hereinafter, also simply referred to as “battery”), an electrode activity capable of reversibly storing and releasing a chemical species that can be a charge carrier on the surface of an electrode current collector. Positive and negative electrodes having a material layer (specifically, a positive electrode active material layer and a negative electrode active material layer) are alternately laminated with a separator made of a porous film interposed therebetween. The separator interposed between the positive and negative electrodes can prevent a short circuit between the positive and negative electrodes and can impregnate the electrolyte and function as a conduction path (conductive path).
ところで、二次電池用セパレータの一形態として、該セパレータを構成する多孔質膜が、水溶性高分子化合物から成る多孔質体で構成されているものが挙げられる。
例えば、特許文献１には、主成分として水溶性高分子化合物であるポリビニルアルコール（ＰＶＡ）を含む多孔質体の製造方法が開示されている。当該方法によれば、水および第１の溶媒（アセトン等）を含むＰＶＡ溶液を冷却して得たＰＶＡ析出物を、第２の溶媒（アセトン等）に浸してＰＶＡ析出物中の水と第１の溶媒との混合溶媒を第２の溶媒に置換してＰＶＡのエマルション液を調製し、高温下で乾燥させることで該エマルション液から第２の溶媒を気化させ、ＰＶＡを主成分とする多孔質体が作製される。これにより、従前は煩雑な操作と高コストを要していた上記多孔質体の製造が、比較的簡便、かつ、より低廉に実現できるようになった。
By the way, as one form of a separator for a secondary battery, there is a case where the porous membrane constituting the separator is composed of a porous body made of a water-soluble polymer compound.
For example, Patent Document 1 discloses a method for producing a porous body containing polyvinyl alcohol (PVA), which is a water-soluble polymer compound, as a main component. According to this method, a PVA precipitate obtained by cooling a PVA solution containing water and a first solvent (acetone or the like) is immersed in a second solvent (acetone or the like) to and water in the PVA precipitate. A PVA emulsion is prepared by replacing the mixed solvent with the solvent of 1 with a second solvent, and the second solvent is vaporized from the emulsion by drying at a high temperature, and the porosity containing PVA as a main component is obtained. A solvent is created. As a result, the production of the above-mentioned porous body, which previously required complicated operations and high cost, can be realized relatively easily and at a lower cost.
しかしながら、上記特許文献１に開示されるＰＶＡを主成分とする多孔質体の製造方法の課題としては、該多孔質体の細孔径が大きく、さらに該細孔径にばらつきが生じ得ることが挙げられる。例えば、多孔質体を形成する過程において、エマルション粒子の表面張力が大きいと、エマルション粒子同士が強く引き付けられる。特にエマルション液の乾燥過程で高温下に置いた場合には、上記エマルション粒子同士が合一してしまい、作製された多孔質体の細孔が粗大化し、細孔径にばらつきが生じるおそれがある。当該多孔質体によって形成される多孔質膜からなるセパレータを使用した場合、かかる多孔質体に生じる細孔の粗大化や細孔径のばらつきは、電池内部における電極の短絡要因、および伝導経路に不均一さが生じ、該不均一さに起因する電池抵抗の上昇の要因にもなり得るため、好ましくない。 However, the problem of the method for producing a porous body containing PVA as a main component disclosed in Patent Document 1 is that the pore size of the porous body is large and the pore size may vary. .. For example, if the surface tension of the emulsion particles is large in the process of forming the porous body, the emulsion particles are strongly attracted to each other. In particular, when the emulsion particles are placed at a high temperature during the drying process, the emulsion particles may coalesce with each other, coarsening the pores of the produced porous body, and causing variations in the pore diameter. When a separator made of a porous film formed by the porous body is used, the coarsening of the pores and the variation in the pore diameter generated in the porous body are not related to the short-circuit factor of the electrode inside the battery and the conduction path. It is not preferable because the uniformity is generated and it can be a factor of increasing the battery resistance due to the non-uniformity.
そこで、本発明は、上述した水溶性高分子化合物からなる二次電池用セパレータの製造に関する課題を解決するべく創出されたものであり、ＰＶＡを含む多孔質膜の細孔を微細化し、かつ、細孔径のばらつきの発生を抑制し得る二次電池のセパレータを製造する方法の提供を目的とする。また、当該製造方法によって製造されたセパレータを備えた二次電池の提供を他の目的とする。 Therefore, the present invention has been created to solve the problem of manufacturing a separator for a secondary battery made of the above-mentioned water-soluble polymer compound, and has been created to make the pores of the porous membrane containing PVA finer and to solve the problem. It is an object of the present invention to provide a method for manufacturing a separator for a secondary battery capable of suppressing the occurrence of variation in pore diameter. Another object of the present invention is to provide a secondary battery provided with a separator manufactured by the manufacturing method.
上記目的を実現するべく、ここで開示される二次電池のセパレータを製造する方法は、以下の（ｉ）、（ｉｉ）の工程を包含する製造方法である。
（ｉ）ポリビニルアルコール（ＰＶＡ）水溶液と、有機溶媒と、シリコーン系分散剤とを混合したエマルション液を作製する工程；および
（ｉｉ）上記作製されたエマルション液を上記二次電池を構成する電極の表面に塗布し、乾燥させて、該電極の表面に多孔質膜からなるセパレータを形成する工程；
を包含する。
In order to realize the above object, the method for manufacturing the separator of the secondary battery disclosed here is a manufacturing method including the following steps (i) and (ii).
(I) A step of preparing an emulsion liquid in which an aqueous solution of polyvinyl alcohol (PVA), an organic solvent, and a silicone-based dispersant are mixed; and (ii) the prepared emulsion liquid is used as an electrode constituting the secondary battery. A step of applying to the surface and drying to form a separator made of a porous film on the surface of the electrode;
Including.
かかる製造方法によると、ＰＶＡ水溶液と、有機溶媒と、シリコーン系分散剤とを混合してエマルション液を調製することで、エマルション粒子の表面張力を低下させることができる。そして、特に乾燥過程における該エマルション粒子の合一を防ぐことができる。これにより、当該エマルション液から作製された多孔質体（多孔質膜）の細孔の粗大化を抑制することができる。また、細孔径のばらつき発生を低減し得る。このため、かかる方法により製造したセパレータを備えた二次電池において、電池内部の短絡、および伝導経路における不均一さの発生を妨げ、該不均一さに起因する電池抵抗の上昇を抑制し得る。 According to such a production method, the surface tension of emulsion particles can be reduced by preparing an emulsion liquid by mixing an aqueous PVA solution, an organic solvent, and a silicone-based dispersant. Then, it is possible to prevent the emulsion particles from coalescing, especially in the drying process. As a result, it is possible to suppress the coarsening of the pores of the porous body (porous film) produced from the emulsion liquid. In addition, it is possible to reduce the occurrence of variation in pore diameter. Therefore, in the secondary battery provided with the separator manufactured by such a method, it is possible to prevent a short circuit inside the battery and the occurrence of non-uniformity in the conduction path, and to suppress an increase in battery resistance due to the non-uniformity.
以下、図面を適宜参照しながら、本発明の好適な実施形態について説明する。なお、本明細書において特に言及している事項以外の事柄であって本発明の実施に必要な事柄は、該分野における従来技術に基づく当業者の設計事項として把握され得る。本発明は、本明細書に開示されている内容と当該分野における技術常識とに基づいて実施することができる。なお、本明細書において「二次電池」とは、繰り返し充放電可能な蓄電デバイス一般をいい、リチウムイオン二次電池、ナトリウムイオン二次電池等のいわゆる蓄電池ならびに電気二重層キャパシタ等の蓄電素子を包含する用語である。また、「リチウムイオン二次電池」とは、電荷担体としてリチウムイオンを利用し、正負極間のリチウムイオンの移動により充放電が行われる二次電池をいう。 Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings as appropriate. Matters other than those specifically mentioned in the present specification and necessary for carrying out the present invention can be grasped as design matters of those skilled in the art based on the prior art in the art. The present invention can be carried out based on the contents disclosed in the present specification and the common general technical knowledge in the art. In the present specification, the “secondary battery” refers to a general storage device that can be repeatedly charged and discharged, and refers to a so-called storage battery such as a lithium ion secondary battery and a sodium ion secondary battery, and a power storage element such as an electric double layer capacitor. It is a term to be included. Further, the "lithium ion secondary battery" refers to a secondary battery that uses lithium ions as a charge carrier and is charged and discharged by the movement of lithium ions between the positive and negative electrodes.
ここで開示される二次電池のセパレータの製造方法は、図１に示すように、エマルション液の作製工程（Ｓ１０）、セパレータの形成工程（Ｓ２０）を包含する。以下、各工程について説明する。 As shown in FIG. 1, the method for manufacturing a separator for a secondary battery disclosed here includes a step of preparing an emulsion liquid (S10) and a step of forming a separator (S20). Hereinafter, each step will be described.
まず、エマルションの作製工程（Ｓ１０）について説明する。かかる工程には、ＰＶＡ水溶液と、有機溶媒と、シリコーン系分散剤とを混合して上記エマルション液を得る工程が含まれる。具体的には、ＰＶＡおよび水から、ＰＶＡ水溶液を得る。次に、該ＰＶＡ水溶液に有機溶媒を加えて混合する。なお、ＰＶＡ水溶液およびＰＶＡ水溶液と有機溶媒の混合液の調製方法としては、従来公知の方法を特に制限なく採用することができる。例えば、スターラー／スターラーバーを用いた撹拌方法が挙げられる。この時、５０～１００℃に加温しながら撹拌を行うことが好ましい。
そして、上記混合液にシリコーン系分散剤を添加し、ホモジナイズし、エマルション液を調製する。なお、シリコーン系分散剤は、ＰＶＡ水溶液を調製する過程で添加してもよく、または、有機溶媒と混合する前のＰＶＡ水溶液に添加してもよい。
ここで「シリコーン系分散剤」とは、分散剤として機能するためのポリマー（高分子化合物）がシロキサン結合（Ｓｉ－Ｏ－Ｓｉ結合）による骨格を有することで規定される分散剤である。例えば、ポリエーテル変性シリコーンからなる分散剤は、ここでいうシリコーン系分散剤に包含される一典型例である。
First, the emulsion preparation step (S10) will be described. Such a step includes a step of mixing an aqueous PVA solution, an organic solvent, and a silicone-based dispersant to obtain the above emulsion liquid. Specifically, an aqueous PVA solution is obtained from PVA and water. Next, an organic solvent is added to the PVA aqueous solution and mixed. As a method for preparing the PVA aqueous solution and the mixed solution of the PVA aqueous solution and the organic solvent, a conventionally known method can be adopted without particular limitation. For example, a stirring method using a stirrer / stirrer bar can be mentioned. At this time, it is preferable to perform stirring while heating to 50 to 100 ° C.
Then, a silicone-based dispersant is added to the above mixture and homogenized to prepare an emulsion. The silicone-based dispersant may be added in the process of preparing the PVA aqueous solution, or may be added to the PVA aqueous solution before being mixed with the organic solvent.
Here, the "silicone-based dispersant" is a dispersant defined by having a skeleton of a siloxane bond (Si—O—Si bond) in a polymer (polymer compound) for functioning as a dispersant. For example, a dispersant made of a polyether-modified silicone is a typical example included in the silicone-based dispersant referred to here.
上記ＰＶＡ水溶液について、ＰＶＡと水との混合比は、ＰＶＡ：水＝１：５程度に設定することが好ましい。即ち、ＰＶＡ水溶液の質量を１００質量％とした場合に、ＰＶＡは１５～２５質量％（あるいは、１８～２２質量％）であり得る。
上記有機溶媒としては、該有機溶媒に対するＰＶＡの溶解度が、水に対する溶解度よりも低い有機溶媒を使用できる。例えば、プロピレンカーボネート（ＰＣ）を好ましく採用し得る。また、ＰＶＡ水溶液と有機溶媒との混合比は、ＰＶＡ水溶液：有機溶媒＝１２：５程度に設定することが好ましい。
For the PVA aqueous solution, the mixing ratio of PVA and water is preferably set to about PVA: water = 1: 5. That is, when the mass of the PVA aqueous solution is 100% by mass, the PVA can be 15 to 25% by mass (or 18 to 22% by mass).
As the organic solvent, an organic solvent having a PVA solubility in water lower than that in water can be used. For example, propylene carbonate (PC) may be preferably adopted. Further, the mixing ratio of the PVA aqueous solution and the organic solvent is preferably set to about 12: 5 of PVA aqueous solution: organic solvent.
上記シリコーン系分散剤としては、効率よくエマルション粒子の表面張力を低下させる観点から、ポリエーテル変性シロキサンの使用が特に好ましい。例えば、ＢＹＫ（登録商標）－３４５，３４６，３４７，３４８，３４９（いずれもビックケミー（BYK-Chemie）社製）等を採用することができる。
シリコーン系分散剤の添加量としては、上記エマルション液を１００質量％とした場合に、０．１質量％～１０質量％（好ましくは０．３質量％～５質量％、さらに好ましくは０．５質量％～２質量％）程度が好ましい。
As the silicone-based dispersant, the use of a polyether-modified siloxane is particularly preferable from the viewpoint of efficiently reducing the surface tension of the emulsion particles. For example, BYK (registered trademark) -345, 346, 347, 348, 349 (all manufactured by BYK-Chemie) and the like can be adopted.
The amount of the silicone-based dispersant added is 0.1% by mass to 10% by mass (preferably 0.3% by mass to 5% by mass, more preferably 0.5) when the emulsion solution is 100% by mass. About% by mass to 2% by mass) is preferable.
次に、セパレータの形成工程（Ｓ２０）について説明する。かかる工程には、上記エマルション液の作製工程（Ｓ１０）により作製したエマルション液を、二次電池を構成する電極の表面に塗布し、乾燥させて、該電極の表面に多孔質膜からなるセパレータを形成する工程が含まれる。具体的には、上記エマルション液をアプリケータ等、従来公知の方法を用いて上記電極の表面、即ち、活物質層等の上に塗布する。そして、上記塗布したエマルション液を高温（４０～１００℃）で乾燥させることで、多孔質膜が形成される。該多孔質膜の細孔径は、例えば、１μｍ以下であり、多孔度は５０％～７０％（より好ましくは、５５％～６５％）になり得る。多孔質膜の多孔度は、質量Ｗ（ｇ）と見かけの体積Ｖ（ｃｍ３）と、真密度ρ（ｇ／ｃｍ３）とから、以下の式（１）により求めることができる。上記「見かけの体積Ｖ」は、平面視での面積（ｃｍ２）と厚み（ｃｍ）の積によって算出することができる。また、上記「真密度ρ」は、一般的な定容積膨張法（気体置換型ピクノメータ法）等の密度測定装置によって測定することができる。
式（１）：〔１－（Ｗ／ρＶ）〕×１００
Next, the separator forming step (S20) will be described. In such a step, the emulsion liquid prepared in the emulsion liquid preparation step (S10) is applied to the surface of the electrode constituting the secondary battery, dried, and a separator made of a porous film is formed on the surface of the electrode. The step of forming is included. Specifically, the emulsion solution is applied onto the surface of the electrode, that is, the active material layer or the like, using a conventionally known method such as an applicator. Then, the coated emulsion liquid is dried at a high temperature (40 to 100 ° C.) to form a porous film. The pore size of the porous membrane is, for example, 1 μm or less, and the porosity can be 50% to 70% (more preferably 55% to 65%). The porosity of the porous film can be determined by the following formula (1) from the mass W (g), the apparent volume V (cm 3 ), and the true density ρ (g / cm 3 ). The above "apparent volume V" can be calculated by the product of the area (cm 2 ) and the thickness (cm) in a plan view. Further, the above-mentioned "true density ρ" can be measured by a density measuring device such as a general constant volume expansion method (gas substitution type pycnometer method).
Equation (1): [1- (W / ρV)] × 100
上述する製造方法によって、二次電池の電極上に多孔質膜からなるセパレータが形成される。
ここに開示される二次電池のセパレータの製造方法によると、シリコーン系分散剤を使用することでエマルション粒子の表面張力を低下させることができる。そのため、エマルション液を電極の表面に塗布して乾燥させる過程においても、エマルション粒子が合一化することを防ぐことができる。これにより、当該エマルション液から作製された多孔質体の細孔の粗大化を抑制することができる。また、細孔径のばらつき発生を低減し得る。このため、かかる方法により製造したセパレータを備えた二次電池において、電池内部の短絡、および伝導経路における不均一さの発生を妨げ、該不均一さに起因する電池抵抗の上昇を抑制し得る。
By the manufacturing method described above, a separator made of a porous film is formed on the electrodes of the secondary battery.
According to the method for manufacturing a separator for a secondary battery disclosed herein, the surface tension of emulsion particles can be reduced by using a silicone-based dispersant. Therefore, it is possible to prevent the emulsion particles from coalescing even in the process of applying the emulsion liquid to the surface of the electrode and drying it. As a result, it is possible to suppress the coarsening of the pores of the porous body produced from the emulsion solution. In addition, it is possible to reduce the occurrence of variation in pore diameter. Therefore, in the secondary battery provided with the separator manufactured by such a method, it is possible to prevent a short circuit inside the battery and the occurrence of non-uniformity in the conduction path, and to suppress an increase in battery resistance due to the non-uniformity.
以下、ここで開示される二次電池のセパレータの製造方法に関する試験例を説明するが、本発明をかかる具体例に示すものに限定することを意図したものではない。 Hereinafter, test examples relating to the method for manufacturing a separator for a secondary battery disclosed herein will be described, but the present invention is not intended to be limited to those shown in such specific examples.
＜実施例＞
－エマルション液の作製－
まず、ＰＶＡのエマルション液を調製するため、ＰＶＡと、水と、ＰＣと、シリコーン系分散剤としてポリエーテル変性シロキサン（ＢＹＫ（登録商標）３４８；ビックケミー社）とを用意した。次に、水を８５℃に加熱した状態で、ＰＶＡ：水（質量％）=１：５となるようにＰＶＡを加えてスターラーを用いて混合した。ここに、ＰＶＡ水溶液：ＰＣ（質量％）＝１２：５となるようにＰＣを加えた混合液をさらに撹拌した。該混合液を室温下静置し、自然冷却させた。ここで、該混合液に、これを１００質量％として、１質量％のポリエーテル変性シロキサンを添加した。そして、該混合液を、ホモジナイザー（プライミクス社）を用いて２，０００ｒｐｍで１０分間ホモジナイズすることにより、実施例に係るＰＶＡのエマルション液を得た。
<Example>
-Preparation of emulsion-
First, in order to prepare an emulsion solution of PVA, PVA, water, PC, and a polyether-modified siloxane (BYK (registered trademark) 348; Big Chemie) were prepared as a silicone-based dispersant. Next, with the water heated to 85 ° C., PVA was added so that PVA: water (% by mass) = 1: 5, and the mixture was mixed using a stirrer. Here, the mixed solution to which PC was added so that PVA aqueous solution: PC (mass%) = 12: 5 was further stirred. The mixture was allowed to stand at room temperature and allowed to cool naturally. Here, 1% by mass of the polyether-modified siloxane was added to the mixed solution, with this as 100% by mass. Then, the mixed solution was homogenized at 2,000 rpm for 10 minutes using a homogenizer (Primix Corporation) to obtain an emulsion solution of PVA according to the examples.
－セパレータの形成－
得られたエマルション液を電極上に市販のアプリケータ（設定膜厚：３ｍｉｌ）で塗工し、６０℃で乾燥させることで、電極の表面に多孔質膜（即ち、セパレータ）を形成した。このように形成した多孔質膜の表面および断面を走査電子顕微鏡にて観察した。その顕微鏡観察画像をそれぞれ図２（Ａ），（Ｂ）に示す。
-Formation of separator-
The obtained emulsion was applied onto the electrode with a commercially available applicator (set film thickness: 3 mil) and dried at 60 ° C. to form a porous film (that is, a separator) on the surface of the electrode. The surface and cross section of the porous film thus formed were observed with a scanning electron microscope. The microscopic observation images are shown in FIGS. 2 (A) and 2 (B), respectively.
＜比較例１＞
エマルション液の作製において、シリコーン系分散剤の代わりに非シリコーン系分散剤であるポリアルコキシレートを使用したこと以外は実施例と同様の材料および工程により、比較例１の多孔質膜（セパレータ）を作成し、その表面および断面を走査電子顕微鏡にて観察した。その顕微鏡観察画像をそれぞれ図３（Ａ），（Ｂ）に示す。
<Comparative Example 1>
In the preparation of the emulsion liquid, the porous film (separator) of Comparative Example 1 was prepared by the same materials and processes as in Examples except that polyalkoxylate, which is a non-silicone-based dispersant, was used instead of the silicone-based dispersant. The surface and cross section thereof were observed with a scanning electron microscope. The microscopic observation images are shown in FIGS. 3 (A) and 3 (B), respectively.
＜比較例２＞
エマルション液の作製において、分散剤を添加しなかったこと以外は実施例と同様の材料および工程により、比較例２の多孔質膜（セパレータ）を作成し、その表面および断面を走査電子顕微鏡にて観察した。その顕微鏡観察画像をそれぞれ図４（Ａ），（Ｂ）に示す。
<Comparative Example 2>
In the preparation of the emulsion, the porous film (separator) of Comparative Example 2 was prepared by the same materials and steps as in the example except that the dispersant was not added, and the surface and cross section thereof were examined by a scanning electron microscope. Observed. The microscopic observation images are shown in FIGS. 4A and 4B, respectively.
図２に示すように、シリコーン系分散剤を使用した実施例では、走査電子顕微鏡観察に基づく多孔質膜の細孔径が１μｍ以下であり、かつ、均一であった。また、該多孔質膜の多孔度は６３％であった。該多孔度は、上述の式（１）により算出した。しかしながら、非シリコーン系分散剤を使用した比較例１（図３参照）および分散剤を使用しなかった比較例２（図４参照）においては、細孔径にばらつきがあり、細孔径が１μｍを超える細孔も多く観察された。
以上の結果から、ここに開示される二次電池のセパレータの製造方法は、ＰＶＡを主成分とする多孔質膜の細孔を微細化し、かつ、細孔径のばらつきの発生を抑制することができる。
As shown in FIG. 2, in the examples using the silicone-based dispersant, the pore diameter of the porous membrane based on the observation with a scanning electron microscope was 1 μm or less and was uniform. The porosity of the porous membrane was 63%. The porosity was calculated by the above formula (1). However, in Comparative Example 1 (see FIG. 3) in which the non-silicone-based dispersant was used and Comparative Example 2 (see FIG. 4) in which the dispersant was not used, the pore diameters varied and the pore diameter exceeded 1 μm. Many pores were also observed.
From the above results, the method for manufacturing a separator for a secondary battery disclosed herein can make the pores of a porous membrane containing PVA as a main component finer and suppress the occurrence of variation in pore diameter. ..
以上、本発明の具体例を詳細に説明したが、これらは例示にすぎず、請求の範囲を限定するものではない。請求の範囲に記載の技術には、以上に例示した具体例を様々に変形、変更したものが含まれる。なお、ここに開示される二次電池のセパレータ製造方法によって作製されたセパレータは、適用される二次電池を制限しない。当該二次電池は、リチウムイオン二次電池であってもよく、ナトリウムイオン二次電池、あるいは他の二次電池であってもよい。 Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The techniques described in the claims include various modifications and modifications of the specific examples exemplified above. The separator manufactured by the method for manufacturing a separator for a secondary battery disclosed herein does not limit the applicable secondary battery. The secondary battery may be a lithium ion secondary battery, a sodium ion secondary battery, or another secondary battery.
Claims (1)
ポリビニルアルコール水溶液と、有機溶媒と、シリコーン系分散剤とを混合したエマルション液を作製する工程；および
前記作製されたエマルション液を前記二次電池の電極の表面に塗布し、乾燥させて、該電極の表面に多孔質膜からなるセパレータを形成する工程；
を包含する、セパレータの製造方法。 A method for manufacturing a separator for a secondary battery, which is the following process:
A step of preparing an emulsion liquid in which an aqueous polyvinyl alcohol solution, an organic solvent, and a silicone-based dispersant are mixed; and the prepared emulsion liquid is applied to the surface of the electrode of the secondary battery, dried, and the electrode is dried. Step of forming a separator made of a porous film on the surface of
A method for manufacturing a separator, which comprises.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018222500A JP7001964B2 (en) | 2018-11-28 | 2018-11-28 | How to manufacture a separator for a secondary battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018222500A JP7001964B2 (en) | 2018-11-28 | 2018-11-28 | How to manufacture a separator for a secondary battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2020087791A JP2020087791A (en) | 2020-06-04 |
| JP7001964B2 true JP7001964B2 (en) | 2022-02-04 |
Family
ID=70908678
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2018222500A Active JP7001964B2 (en) | 2018-11-28 | 2018-11-28 | How to manufacture a separator for a secondary battery |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7001964B2 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012251057A (en) | 2011-06-01 | 2012-12-20 | Osaka Univ | Porous body of polyvinyl alcohol and method for producing the same |
| JP2013144442A (en) | 2013-02-27 | 2013-07-25 | Asahi Kasei Chemicals Corp | Porous film including both high heat resistance and high transmittance, and method for manufacturing the same |
| JP2014061458A (en) | 2012-09-20 | 2014-04-10 | Japan Vilene Co Ltd | Method of producing porous sheet imparted with polyvinyl alcohol resin |
| JP2014229428A (en) | 2013-05-21 | 2014-12-08 | 協立化学産業株式会社 | Coating material composition for battery electrodes or separators having excellent adhesion |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0678460B2 (en) * | 1985-05-01 | 1994-10-05 | 株式会社バイオマテリアル・ユニバース | Porous transparent polyvinyl alcohol gel |
| JP4008508B2 (en) * | 1997-12-22 | 2007-11-14 | 三菱電機株式会社 | Method for producing lithium ion secondary battery |
-
2018
- 2018-11-28 JP JP2018222500A patent/JP7001964B2/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012251057A (en) | 2011-06-01 | 2012-12-20 | Osaka Univ | Porous body of polyvinyl alcohol and method for producing the same |
| JP2014061458A (en) | 2012-09-20 | 2014-04-10 | Japan Vilene Co Ltd | Method of producing porous sheet imparted with polyvinyl alcohol resin |
| JP2013144442A (en) | 2013-02-27 | 2013-07-25 | Asahi Kasei Chemicals Corp | Porous film including both high heat resistance and high transmittance, and method for manufacturing the same |
| JP2014229428A (en) | 2013-05-21 | 2014-12-08 | 協立化学産業株式会社 | Coating material composition for battery electrodes or separators having excellent adhesion |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2020087791A (en) | 2020-06-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Liu et al. | Effect of Al2O3/SiO2 composite ceramic layers on performance of polypropylene separator for lithium-ion batteries | |
| CN101896424B (en) | Metal encapsulated dendritic carbon nanostructure, carbon nanostructure, process for producing metal encapsulated dendritic carbon nanostructure, process for producing carbon nanostructure, and capacitor | |
| US20160268638A1 (en) | Method of manufacturing all-solid battery through wet-dry mixing process | |
| Lake et al. | Graphene metal oxide composite supercapacitor electrodes | |
| JP2007048525A (en) | Cathode material for nonaqueous electrolyte lithium ion battery, and battery using the same | |
| US11264616B2 (en) | Conductive composition for electrodes, and electrode and battery using same | |
| CN102884003A (en) | Lithium titanate crystal structure, complex of lithium titanate crystal structure and carbon, manufacturing method for same, electrode and electrochemical element using same | |
| JP2011165637A (en) | Positive electrode collector, method of manufacturing the same, and positive electrode body for lithium ion battery | |
| JP6321420B2 (en) | Electrode and manufacturing method thereof | |
| CN105977488A (en) | Method for manufacturing positive active material for all-solid lithium-sulfur battery | |
| He et al. | Preparation and electrochemical performance of monodisperse Li 4 Ti 5 O 12 hollow spheres | |
| CN105047857B (en) | The positive pole and its manufacture method of rechargeable nonaqueous electrolytic battery | |
| KR20150114072A (en) | Manufacturing method of natrium ion battery anode material | |
| JP7001964B2 (en) | How to manufacture a separator for a secondary battery | |
| Jianrong et al. | Preparation and lithium storage properties of active carbon–CNT/sulfur composite | |
| CN112368859A (en) | Ethyl cellulose as dispersant for lithium ion battery cathode production | |
| JP2013165052A (en) | Material for air cell and all-solid air cell using the same | |
| JP2011192499A (en) | Positive electrode for nonaqueous electrolyte battery and nonaqueous electrolyte battery | |
| JP6846745B2 (en) | Electrode sheet and non-aqueous electrolyte secondary battery used for non-aqueous electrolyte secondary battery | |
| JP7475081B2 (en) | Composite separator for lithium secondary battery and method for producing same | |
| JP6176129B2 (en) | Silicon-based nanomaterial composite, method for producing the same, apparatus, negative electrode active material for lithium ion secondary battery including silicon-based nanomaterial composite, electrode, and power storage device | |
| CN103715404B (en) | A kind of preparation method of graphene oxide cladding lithium salts | |
| KR101468582B1 (en) | Preparation method of electrode active material using porous silica support, and the electrode active material | |
| CN115485882A (en) | Conformal Pickering Emulsion Graphene Coatings for Electrode Materials, Formation Methods and Applications | |
| CN106601989B (en) | A kind of porous film electrode material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20201216 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20211116 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20211125 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20211208 |
|
| R151 | Written notification of patent or utility model registration |
Ref document number: 7001964 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R151 |