JPS59126782A - Electrode plate for electrolytic cell - Google Patents

Abstract

PURPOSE:To provide a titled electrode plate which can decrease leakage current by the constitution wherein the content of a conductive material in the electrode plate in the flow passage parts for an electrolyte is made lower than the content in the electrolytic chamber part to increase the electric resistance in the flow passage parts. CONSTITUTION:A plate-shaped electrode plate 3 is constituted of a synthetic resin of PE, etc. incorporated with about >=50wt% a conductive material such as carbon powder or metallic powder, in a lamination type electrolytic cell obtd. by laminating a diaphragm 5, a frame-shaped spacer 1 and the electrode 3. The content of the above-mentioned conductive material in the part around electrolyte flow holes 6A, 6B, 10, etc. except an electrolytic chamber is made <=70% of the content in the electrolyte part to increase the electric resistance therein. The leakage current flowing through the frame body, holder, soln., etc. from the peripheral part of the plate 3 is considerably decreased and the working in the peripheral part contg. the conductive material in the smaller amt. is made easy.

Description

【発明の詳細な説明】 本発明は電解槽用電極板に関し、さらに詳しくは導電性
物質を含む合成樹脂材料を用いた電解槽用電極板に関す
るものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrode plate for an electrolytic cell, and more particularly to an electrode plate for an electrolytic cell using a synthetic resin material containing a conductive substance.

従来、電解液流通孔を設けた合成樹脂板を組合せ、正極
室と負極室を隔膜を介して重ね合せた積層型電解槽が知
られている。第１図はこのような積層型電解槽の典型例
を示すもので、隔膜５と、枠状スペーサー１と、この隔
膜５および枠状スペーサーをはさんで負極側および正極
側（一方のみ図示）にそれぞれ対称形に積層された導電
性物質を含む板状電極３とから構成される。正極液（−
！。2. Description of the Related Art Conventionally, a stacked electrolytic cell is known in which a positive electrode chamber and a negative electrode chamber are stacked with a diaphragm interposed in between synthetic resin plates provided with electrolyte flow holes. Fig. 1 shows a typical example of such a stacked electrolytic cell, which includes a diaphragm 5, a frame-shaped spacer 1, and a negative electrode side and a positive electrode side (only one shown) with the diaphragm 5 and frame-shaped spacer in between. and plate-shaped electrodes 3 each containing a conductive material laminated symmetrically. Positive electrode liquid (−
! .

たは負極液）は、板状電極３の電解液流通孔６Ａを通り
、その上部のスペーサー１の枠内空間２から電極面上に
流れ、他方の枠内空間の流通孔から外部または次の電解
槽に流される。一方、負極液（または正極液）は、流通
孔６Ｂから隔膜５をはさんで対称に設置されたスペーサ
ー（図示せず）の枠内空間から同様に流入され、排出さ
れる。The electrolyte (or negative electrode liquid) passes through the electrolyte distribution hole 6A of the plate electrode 3, flows from the frame space 2 of the spacer 1 above it onto the electrode surface, and flows from the communication hole of the other frame space to the outside or the next Flowed into an electrolytic bath. On the other hand, the negative electrode liquid (or positive electrode liquid) similarly flows in and is discharged from the space within the frame of a spacer (not shown) installed symmetrically with the diaphragm 5 in between from the flow hole 6B.

上記電解槽に用いる電極板は導電性物質を含有させるこ
とにより電気伝導性を有しているが、−゛このような電
極板では、極板全域が電気の良導体の場合、電解液の流
通路部分を通って電流が電解室外に漏洩するという欠点
がある。このよう外漏洩電流は、電解槽の電極間を通る
電流ではなく、目的とする電解反応（または電池反応）
に通常関与せず無効な電力となるものである。The electrode plate used in the above electrolytic cell has electrical conductivity by containing a conductive substance. The disadvantage is that current leaks out of the electrolysis chamber through the parts. This type of external leakage current is not the current passing between the electrodes of the electrolytic cell, but the target electrolytic reaction (or battery reaction).
It is normally not involved and becomes ineffective power.

本発明の目的は、上記従来技術の欠点を除去し、電解槽
からの漏洩電流を可及的に小さくすることができる電解
槽用電極を提供することにある。An object of the present invention is to provide an electrode for an electrolytic cell that can eliminate the drawbacks of the prior art described above and can reduce leakage current from the electrolytic cell as much as possible.

本発明者らは、電解液流路の電気抵抗を小さくする要因
をできるだけ取シ除くため、電解室外の電解液流路部分
の電極板中に含まれる導電性物質を少なくすることによ
シ、該部分の電気抵抗が増大し、漏洩電流を小さくする
ことを見出し、本発明に到達したものである。In order to eliminate as much as possible the factors that reduce the electrical resistance of the electrolyte flow path, the present inventors have achieved The present invention was achieved by discovering that the electrical resistance of this portion increases and the leakage current decreases.

本発明は、導電性物質を含む合成樹脂からなる電解槽用
電極板において、電解室外の液流路部分の導電性物質の
含有率を電解室部分含有率の′７０％以下としたことを
特徴とする。The present invention is characterized in that, in an electrode plate for an electrolytic cell made of a synthetic resin containing a conductive substance, the content of the conductive substance in the liquid flow path portion outside the electrolytic chamber is 70% or less of the content in the electrolytic chamber portion. shall be.

本発明は、電解槽のみならず、電解槽と同様な構成の電
池にも同様に適用されるので、本明細書中の電解槽また
は電極板なる用語は電池または極板と同義であり、勿論
、本特許請求の範囲に含まれる。The present invention applies not only to electrolytic cells but also to batteries having the same configuration as electrolytic cells, so the term electrolytic cell or electrode plate in this specification is synonymous with battery or electrode plate, and of course , within the scope of the present claims.

本発明において、樹脂中に含有させる導電性物質として
は炭素粉、金属粉等の電子伝導性物質の他、正孔やイオ
ンによる伝導性を有するもの、すなわち各種半導体や固
体電解質等があげられる。In the present invention, examples of the conductive substance contained in the resin include electron conductive substances such as carbon powder and metal powder, as well as substances having hole and ion conductivity, such as various semiconductors and solid electrolytes.

本発明の電極板を形成する合成樹脂は、電極板を構成し
得るものであればどのようなものでもよく、例えばポリ
エチレン、ポリプロピレン、ポリを有するものがあげら
れる。上記合成樹脂中に含有させる導電性物質の量は、
電解または反応を行なう上で充分な導電性を与える量で
よいが、例えば金属粉等の場合は約５０重量％以上であ
る。本発明において電解室外の電解液流路の周囲を構成
する合成樹脂は導電性物質を含まないことが望ましいが
、実質的には電気導通部分の７０重量％以下（好ましく
は５０重量％以下）含んでいても電気抵抗は充分に大き
くなり、本発明の目的を達成することができる。導電性
物質は電極室部分では樹脂中に均一に含有されているこ
とが好ましい。The synthetic resin forming the electrode plate of the present invention may be any resin as long as it can form the electrode plate, and examples include those containing polyethylene, polypropylene, and poly. The amount of conductive substance contained in the synthetic resin is
The amount may be any amount that provides sufficient conductivity for electrolysis or reaction, but for example, in the case of metal powder, the amount is approximately 50% by weight or more. In the present invention, it is preferable that the synthetic resin surrounding the electrolyte flow path outside the electrolytic chamber does not contain a conductive substance, but it does not substantially contain 70% by weight or less (preferably 50% by weight or less) of the electrically conductive part. However, the electrical resistance becomes sufficiently large and the object of the present invention can be achieved. It is preferable that the conductive substance is uniformly contained in the resin in the electrode chamber portion.

なお、電極板の製作上は、例えば固体電解質を多量に含
有する合成樹脂は脆くて加工しにくく、かつボルトなど
で締めっけることも困難であるが、電極板の周辺部（電
解液流通部）は固体電解質を多量に含まず、比較的加工
しやすいので、製作上有利であシ、強度低下も問題にな
らない。When manufacturing electrode plates, for example, synthetic resin containing a large amount of solid electrolyte is brittle and difficult to process, and it is also difficult to tighten with bolts. ) does not contain a large amount of solid electrolyte and is relatively easy to process, so it is advantageous in manufacturing, and there is no problem with a decrease in strength.

以下、水元明釜実施例によりさらに詳細に説明する。Hereinafter, it will be explained in more detail with reference to examples of Mizumoto Ake pot.

実施例１ 第２図に示す複極板を積層して電解槽を試作した。複極
板の合成樹脂シートは、第２図に示すよりに液流通孔を
含むシート両端部分に炭素粉を中央部分の４０〜６０重
量％程度含有するフッ素樹脂結着シートであ凱これにス
ペーサーと隔膜とを重ねて一つの単電解槽を構成した。Example 1 An electrolytic cell was fabricated by stacking the bipolar plates shown in FIG. 2. As shown in Fig. 2, the synthetic resin sheet of the bipolar plate is a fluororesin binding sheet containing carbon powder in an amount of about 40 to 60% by weight of the central portion at both end portions of the sheet including liquid flow holes, and spacers are added to this sheet. and a diaphragm were stacked to form one single electrolytic cell.

この単電解槽を二個重ね合わせて複極電解槽とした。な
お、漏洩電流測定の際には、隔膜の代ゎシに軟質のポリ
塩化ビニルシートを用いて隔膜部を電気的に絶縁した。Two of these single electrolytic cells were stacked together to form a bipolar electrolytic cell. When measuring leakage current, a soft polyvinyl chloride sheet was used in place of the diaphragm to electrically insulate the diaphragm.

電解槽に１モル／１塩化ナトリウム水溶液を浦たし、両
複極板間の電気抵抗を交流ブリッジ法および回路試験器
で測定した。なお、第２図に示す両端が灰白色で、はと
んど炭素粉を含まない複極板を用いた場合と、比較のた
めに複極板全域に、ｔ’ｔｔ”ｉ’均一の炭素粉を含有
するものについても、同様に検討した。その結果、複極
板の両端部も中央部と同じく炭素粉を均一に含有する場
合の抵抗をｌとすると、４．０〜６０重量％を含む場合
は１０゜はとんど含まないものは１２であった。この結
果、電解液流路を通って流れる漏洩電流は本発明によシ
、大きく低減されることが明らかになった。A 1 mol/1 aqueous sodium chloride solution was poured into the electrolytic cell, and the electrical resistance between both bipolar plates was measured using an AC bridge method and a circuit tester. In addition, for comparison, a bipolar plate with gray-white ends and almost no carbon powder is used as shown in Fig. 2, and a case in which a bipolar plate with uniform carbon powder is used over the entire bipolar plate. A similar study was conducted on those containing carbon powder.As a result, it was found that both ends of the bipolar plate contain 4.0 to 60% by weight, assuming that the resistance is 1 when both ends of the bipolar plate contain carbon powder uniformly like the center. In the case of 10°, the value of 12 was 12. As a result, it was revealed that the leakage current flowing through the electrolyte flow path was greatly reduced by the present invention.

第３図は、本発明の他の実施例を示す複極板の斜視図で
ちるが、この場合は周辺部の電解液流通孔１０の他に中
央部にも流通孔１１が形成され、この中央部の樹脂中の
導電性物質の含量も周辺部のそれと同様に少なくなって
いる。このような構成としても、実施例１と同様に漏洩
電流を減少させることができる。−まだ流通孔を多く形
成しても、その部分には導電性物質があ寸り含まれてい
ないので、強度、耐久性等に悪影響を及ばずことがない
。FIG. 3 is a perspective view of a bipolar plate showing another embodiment of the present invention. In this case, in addition to the electrolyte flow holes 10 at the periphery, flow holes 11 are also formed in the center. The content of the conductive substance in the resin at the center is also small, similar to that at the periphery. Even with such a configuration, leakage current can be reduced similarly to the first embodiment. - Even if a large number of communication holes are formed, there is no adverse effect on strength, durability, etc., because the conductive material is not contained in those portions.

以上、本発明によれば、板状電極の液流通孔の周辺部分
は比較的高い電気抵抗をもつため、電極板の周辺部から
導電性枠体、ホルダー、溶液を通って流れる漏洩電流を
大幅に低減することができる。また電極を構成する板状
材料の中央部に導電性物質を多く存在させ、液流通孔等
の加工部分の多い周辺部には導電性物質が少ない（また
は存在しない）ので、強度の弱い電極材料（マトリック
ス材料）でも充分使用可能となり、また耐久性も向上す
る。As described above, according to the present invention, since the peripheral portion of the liquid flow hole of the plate electrode has a relatively high electrical resistance, the leakage current flowing from the peripheral portion of the electrode plate through the conductive frame, the holder, and the solution can be significantly reduced. can be reduced to In addition, a large amount of conductive material is present in the central part of the plate-like material that constitutes the electrode, and there is less (or no) conductive material in the peripheral part where there are many processed parts such as liquid flow holes, so the electrode material has weak strength. (matrix material) can be used satisfactorily, and durability is also improved.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は、本発明の板状電極−が用いられる液流通型電
解槽の一例を示す展開図、第２図および第３図は、それ
ぞれ本発明の一実施例を示す板状電極の斜視図である。 図中の符号１はスペーサー、３は（板状）電極、Ｃ５は
隔膜、１０．１１は液流通孔を示す。 代理人　弁理士　川　北　武　長 第１因FIG. 1 is a developed view showing an example of a liquid flow type electrolytic cell in which a plate electrode of the present invention is used, and FIGS. 2 and 3 are perspective views of plate electrodes each showing an embodiment of the present invention. It is a diagram. In the figure, reference numeral 1 indicates a spacer, 3 indicates a (plate-shaped) electrode, C5 indicates a diaphragm, and 10.11 indicates a liquid flow hole. Agent Patent Attorney Takeshi Kawakita 1st cause

Claims (1)

【特許請求の範囲】[Claims] （１）導電性物質を含む合成樹脂からなる電解槽用電極
板において、電解室外の液流路部分の導電性物質の含有
率を電解室部分の含有率の７０％以下としたことを特徴
とする電解槽用電極板。(1) An electrode plate for an electrolytic cell made of a synthetic resin containing a conductive substance, characterized in that the content of the conductive substance in the liquid flow path outside the electrolytic chamber is 70% or less of the content in the electrolytic chamber. Electrode plates for electrolytic cells.