JP2506835B2 - Manufacturing method of solid electrolyte battery - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a solid electrolyte battery in which all constituent materials are solid substances.

Conventional technology Solid electrolyte batteries, whose constituent materials are all solid substances,
Compared to batteries that use a liquid electrolyte that requires a certain size,
There is no worry of liquid leakage or gas generation. In addition, since it does not require a container of a certain size, the shape can be arbitrarily selected, and it is extremely easy to make it small and thin, and it can be stored in the same package as other electronic parts. It has many advantages. However, this solid electrolyte battery has a problem that it is extremely weak against mechanical shock and is easily damaged.

In order to eliminate this problem, the present inventors have proposed a method of imparting flexibility to a solid electrolyte battery by mixing an organic binder having plasticity with an electrode or a solid electrolyte.

Problems to be Solved by the Invention A core material is placed on a plastic sheet coated with Teflon or a release agent having high releasability, and an electrode forming ink or a solid electrolyte ink is applied and dried to form an electrode sheet or a solid electrolyte sheet. When prepared, the contact area between the electrode sheet or solid electrolyte sheet and Teflon or plastic sheet dries slowly, and while the electrode material powder or solid electrolyte powder is trapped in the core material, the organic binder dissolved in an organic solvent is used. The adhesive passes through the filling layer of the electrode material powder or the solid electrolyte powder of the core material, and forms the film of the organic adhesive at the contact portion between the electrode sheet or the solid electrolyte sheet and the Teflon or the plastic sheet. Because of these, it takes time to dry the electrode sheet or the solid electrolyte sheet, and the solid electrolyte battery made from this electrode sheet and the solid electrolyte sheet has a high internal resistance due to the presence of the organic binder film on the sheet surface. However, there is a problem that the discharge capacity becomes small.

Means for Solving the Problems In order to solve the above problems, the present invention applies a solid electrolyte ink or a positive electrode and negative electrode electrode forming ink to a core material, and then dries it in a non-contact state with other members. To produce a solid electrolyte sheet or an electrode sheet for a positive electrode and a negative electrode, and pressure-bond these sheets to produce a solid electrolyte battery.

In the method for producing a solid electrolyte battery according to the present invention, the solid electrolyte ink or the electrode forming ink for the positive electrode and the negative electrode is applied to the core material, and then the sheet is dried from both sides of the sheet in a non-contact state. Drys quickly and does not form a high resistance film of organic binder on the surface of the sheet.
In the sheet, the organic binder is substantially uniformly dispersed because it permeates and is retained in the gap between the organic solvent or the solid electrolyte powder in which the organic binder is dissolved, or the electrode material powder of the positive electrode and the negative electrode.

Example In this example, 20% by weight of the above solid electrolyte powder was added to RbCu ₄ I _1.5 Cl _3.5 as a solid electrolyte and Cu ₂ Mo ₆ S _7.8 as an electrode material, and after sufficiently pulverizing and mixing, 3 ton / cm ² Press-molded with, heat treated under reduced pressure at 200 ℃ for 17 hours, crushed, then used solid electrolyte ink and electrode forming ink prepared as follows using the above solid electrolyte powder and electrode material powder I was there.

Solid electrolyte ink is dry inert gas (N ₂ , Ar, He)
2.6 wt% styrene-butylene rubber powder as an organic binder was added to the solid electrolyte powder in the atmosphere, and toluene was added as an organic solvent with stirring to dissolve the organic binder,
Propylene glycol dehydrated using molecular sieve 0.3 nm dried at about 300 ° C was added as a high boiling organic substance, and after ultrasonic treatment, a solid electrolyte ink was prepared by adjusting the viscosity so that it could be easily applied. Was prepared by adding 1% by weight of styrene-butylene rubber powder to the electrode material powder in a dry inert gas atmosphere and by the same method as for the solid electrolyte ink.

Example 1 The solid electrolyte ink and the electrode forming ink were separately applied to different polypropylene nonwoven fabrics (core materials) by using a frame in which the core material shown in FIG. 1 is evenly stretched in the air, It was dried under reduced pressure at 100 ° C. to prepare a solid electrolyte sheet and an electrode sheet. In FIG. 1, 11 is a clip for holding the core material, 12 is an elastic rubber band, 13 is a core material, and 14 is a frame.

These sheets were punched out to a diameter of 10 mm and the solid electrolyte sheet was press-molded at 3 ton / cm ² to obtain a solid electrolyte molded body (about
Electrode sheets (200 mg) are placed on both sides of 70 mg) 3
Press molding at ton / cm ² to make a solid electrolyte battery.
It was charged at 6 V for 24 hours and discharged at 1 mA / cm ² . The discharge characteristics are shown in FIG.

For comparison, a solid electrolyte battery (about 70 mg) and a solid electrolyte battery made from a solid electrolyte sheet (about 70 mg) and an electrode sheet (200 mg) prepared by placing a polypropylene nonwoven fabric on a Teflon sheet and applying solid electrolyte ink and ink for forming electrodes The same charge and discharge was performed for the solid electrolyte battery prepared by using the powder (500 mg) and the electrode material powder (200 mg). The discharge characteristics are also shown in FIG.

Whereas the discharge capacity of the solid electrolyte battery composed of the solid electrolyte sheet and the electrode sheet formed by stretching the polypropylene nonwoven fabric in the frame showed almost the same discharge capacity as the solid electrolyte battery prepared from the solid electrolyte powder and the electrode material powder, The discharge capacity of the solid electrolyte battery composed of the solid electrolyte sheet and the electrode sheet made by placing the polypropylene nonwoven fabric on the Teflon sheet was less than half that of the solid electrolyte battery made of the solid electrolyte powder and the electrode material powder. This is because in a solid electrolyte battery consisting of a solid electrolyte sheet and an electrode sheet made by placing a polypropylene non-woven fabric on a Teflon sheet, a film made of an organic binder is formed at the contact part between the Teflon sheet and the solid electrolyte sheet or the electrode sheet. Formed, which reduces the discharge capacity.

(Example 2) Using the prototype device shown in FIG. 3, the solid electrolyte ink and the electrode forming ink were impregnated into different polypropylene nonwoven fabrics (core materials) and dried to form the solid electrolyte sheet and the electrode sheet. Created.

A method for producing a solid electrolyte sheet and an electrode sheet will be described with reference to FIG. The core material sheet 1 passes through the guide roller 2 and is immersed in the solid electrolyte ink or the electrode forming ink tank 3, and the gas in the core material sheet is pushed out by the roller press 4 in the ink tank. In the ink tank after the roller pressing, the pressed core material sheet returns to the original state, at which time the solid electrolyte ink or the electrode forming ink is impregnated in the core material sheet and is pulled up through the guide roller 2. The surface of the core material sheet is smoothed by the slits 5, and the core material sheet impregnated with the solid electrolyte ink or the electrode forming ink is dried by the dryer 6 to become the solid electrolyte sheet or the electrode sheet. In FIG. 1, 7 is a shielding plate for preventing hot air of the dryer from hitting the slit, 8 is a partition wall for preventing diffusion of bubbles extruded from the core material, and 9 is a propeller for stirring ink. .

The solid electrolyte sheet is punched out to a diameter of 10 mm, 3 tons / c
Electrode sheets (200 mg) punched out with a diameter of 10 mm were placed on both sides of a solid electrolyte molded body (about 70 mg) that was press-molded with m ² and press-molded with 3 ton / cm ² to create a solid electrolyte battery, 0.6 V, It was charged for 24 hours and discharged at 1 mA / cm ² . The discharge characteristics are shown in FIG.

For comparison, as in Example 1, a polypropylene nonwoven fabric was placed on a Teflon sheet, and a solid electrolyte battery and an electrode sheet were prepared by applying a solid electrolyte ink and an electrode-forming ink, and a solid electrolyte battery, a solid electrolyte powder, and an electrode. The same charge and discharge was performed for the solid electrolyte battery prepared using the material powder. The discharge characteristics are also shown in FIG.

The discharge capacity of the solid electrolyte battery prepared by the manufacturing method of this example was almost the same as that of the solid electrolyte battery prepared from the solid electrolyte powder and the electrode material powder.

Although only the method of vertically lifting the core material sheet impregnated with the electrode forming ink or the solid electrolyte ink is described in this embodiment, the core material sheet impregnated with the electrode forming ink or the solid electrolyte ink is drawn horizontally. Even if it is dried, the same electrode sheet or solid electrolyte sheet can be obtained.

(Example 3) The solid electrolyte ink and the electrode-forming ink were separately applied to different polypropylene nonwoven fabrics (core materials) by spraying using the frame shown in FIG. 1 in which the core material is evenly stretched, It was dried to prepare a solid electrolyte sheet and an electrode sheet.

The solid electrolyte sheet is punched out to a diameter of 10 mm, 3 tons / c
Diameter 10 mm on both sides of solid electrolyte sheet pressed by m ²
Place the electrode sheets (200 mg) punched out in step 3 and press-mold at 3 ton / cm ² to make a solid electrolyte battery.
After charging at V for 24 hours, 1 mA / cm ² was discharged. The discharge characteristics are shown in FIG.

For comparison, as in Example 1, a polypropylene nonwoven fabric was placed on a Teflon sheet, and a solid electrolyte ink and an electrode-forming ink were applied and dried to prepare a solid electrolyte sheet and a solid electrolyte battery prepared using the electrode sheet. The same charge and discharge was performed for the solid electrolyte battery prepared by using the solid electrolyte powder and the electrode material powder. The discharge characteristics are also shown in FIG.

The discharge capacity of the solid electrolyte battery prepared by the manufacturing method of this example was almost the same as that of the solid electrolyte battery prepared from the solid electrolyte powder and the electrode material powder.

EFFECTS OF THE INVENTION As described above, according to the method for producing a solid electrolyte battery of the present invention, the solid electrolyte battery has almost the same discharge capacity as that of the solid electrolyte battery prepared by using the powder material, and is smaller than the case using the powder material , It is possible to easily make a thin solid electrolyte battery.

[Brief description of drawings]

FIG. 1 is a process chart of a manufacturing method according to an embodiment of the present invention,
FIG. 2 is a discharge characteristic diagram of the solid electrolyte battery manufactured by the same manufacturing method.
FIG. 3 is a block diagram of a prototype device embodying the manufacturing method, and FIG.
FIG. 5 and FIG. 5 are discharge characteristic diagrams of solid electrolyte batteries according to different embodiments of the present invention. 11 …… Clamps for grasping the core material, 12 …… Rubber straps, 13 …… Core material, 14 …… Frame, 1 …… Core material, 2 …… Guide rollers, 3…
… Ink tank, 4 …… Press roller, 5 …… Slit, 6
... Dryer, 7 ... Shield, 8 ... Partition, 9 ... Propeller.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeo Kondo 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Masaki Nagata 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic rubber Co., Ltd. (72) Inventor Naofumi Yasuda 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (7)

(57) [Claims] 1. A solid electrolyte ink containing an organic binder, an organic solvent, and a solid electrolyte material powder, an organic binder,
A positive electrode ink containing an organic solvent and a positive electrode material powder, and a negative electrode ink containing an organic binder, an organic solvent, and a negative electrode material powder were separately applied to a core material and then held on the core material. The solid electrolyte ink, the positive electrode ink, and the negative electrode ink are dried in a state of not substantially contacting a holding material other than the core material to remove the organic solvent to form a solid electrolyte sheet, a positive electrode sheet, and a negative electrode sheet, After that, the solid electrolyte sheet, the positive electrode sheet, and the negative electrode sheet are pressure-bonded, or the respective sheets are cut and pressure-bonded to each other. 2. The method for producing a solid electrolyte battery according to claim 1, wherein the solid electrolyte ink, the positive electrode ink or the negative electrode ink is applied to and retained on the core material by using a brush or a sponge roller. . 3. The method for producing a solid electrolyte battery according to claim 1, wherein the solid electrolyte ink, the positive electrode ink or the negative electrode ink is impregnated and held on the core material. 4. The method for producing a solid electrolyte battery according to claim 1, wherein the solid electrolyte ink, the positive electrode ink, or the negative electrode ink is applied and held on the core material by spraying. 5. The method for producing a solid electrolyte battery according to any one of claims 1 to 4, wherein the solid electrolyte material is a compound containing RbCl, RbI, CuCl, CuI. 6. The positive electrode material or the negative electrode material has the chemical formula Cu ₂ Mo ₆
The method for producing a solid electrolyte battery according to any one of claims 1 to 4, which is a mixture of a copper Chevrel phase compound represented by S ₈ and a solid electrolyte material. 7. The organic binder is an anhydrous or dehydrated plasticized organic substance, and the organic solvent is an anhydrous or dehydrated high-boiling-point organic substance. Item 8. A method for producing a solid electrolyte battery according to any one of items.