WO2000070696A1

WO2000070696A1 - Collector for storage battery, storage battery comprising the same, and method for manufacturing the storage battery

Info

Publication number: WO2000070696A1
Application number: PCT/JP2000/003145
Authority: WO
Inventors: Isamu Kurisawa
Original assignee: Japan Storage Battery Co., Ltd.
Priority date: 1999-05-18
Filing date: 2000-05-17
Publication date: 2000-11-23
Also published as: DE10081688T1

Abstract

A collector for a storage battery the voltage drop of which is little, and which has an excellent corrosion resistance, a storage battery comprising the same, and a method for manufacturing the storage battery are disclosed. The collector comprises a collector base and a thin conductive ceramic film formed on the collector base.

Description

Specification

Current collector for storage battery, storage battery using the same, and method for manufacturing the storage battery

The present invention relates to a current collector for a storage battery, a storage battery using the same, and a method for manufacturing the storage battery. Background technology>

Materials for the positive electrode current collector are required to have high conductivity, insolubility in the electrolyte, chemical stability at the positive electrode potential in the electrolyte, and high hydrogen / oxygen overvoltage. Materials such as carbon and / or inexpensive and lightweight metal such as aluminum can not be used because they are significantly dissolved or corroded when exposed to the positive electrode potential in the electrolyte. Most metallic materials cannot be used due to corrosion, melting, etc., and such corrosion-resistant conductive materials can be found slightly in ceramics such as oxygen compounds and silicon compounds. _{(Example: Sn0 2, T i S i} 2, T i 5 S i 3, TaS i 2, TaS i 3, NbS i 2, Nb 5 S i 3 , etc.)

However, these conductive ceramic material is said to be excellent conductivity (volume resistance is 1 OMEGA. cm or less), and metal (volume resistivity ^{^{1 0- 6 ~ 1 0_ 5 Ω}} · cm or less) By comparison, these materials could not be used directly as current collectors because of their high specific resistance or high cost. However, by forming a thin film of the conductive ceramic on the surface of the current collector and coating the current collector base material, the voltage drop due to the conductive ceramic can be suppressed small, and the problem of specific resistance and cost reduction The problem is overcome, and a positive electrode current collector with excellent corrosion resistance can be obtained. For this reason, several electrode systems coated with conductive ceramics have been reported.

Example: Electrochemistry 47, 668 (1 979), 48, 384 (1 980)

T i (base) / Sn0 ₂ (Sb-doped) / -? Pb_〇 ₂

T i _{(base) / P t O x / S-} Pb0 2 T i (substrate) / I r 0 ₂ / 5-Pb0 ₂

T i (substrate) / Ru0 ₂ / 5— Pb0 ₂

As a practical example of such an electrode coated with a conductive ceramic, there is a lead dioxide electrode used for a DSA electrode for electrolysis.

Example: JP-A-63-57791

T i (base material) / Platinum / Hiichi Pb0 ₂ /? — Pb0 ₂ … DS made by Bernoullek

A electrode

The reason why these electrodes use Ti as a base material is that the thin-film manufacturing method uses the liquid phase as a medium, so that the usual dip coating method would disperse the organic metal, In order to obtain good crystallinity and conductivity of the material, a process called firing, in which the substrate temperature rises to around 500 ° C, is required during the film forming process. In addition, even when using a spray pyrolysis method that precipitates from a liquid phase, which is widely used industrially, a process of raising the substrate temperature to at least about 340 ° C was necessary, so the melting point such as Ti Unless a current collector of high quality is used, a corrosion-resistant thin film having good characteristics cannot be formed on the surface. However, with such a positive electrode current collector made of Ti or a refractory metal, there is a problem that processing and welding of the electrode plate are difficult to manufacture a storage battery, and the assembly cost is increased.

When exposed to the electrolyte at the positive electrode potential, Ti is anodic oxidized in a short period of time and becomes passivated, so that the electrolyte enters the interface between the current collector base material and the coating film. If so, there is a problem that the function as a current collector cannot be maintained. Furthermore, in the conventional film forming method of depositing from the liquid phase, the adhesion between the film and the substrate is small, and the film has many defects such as cracks. There was a problem that the electrolytic solution penetrated from the cracked portion and the surface of the base material was anodic oxidized, so that the corrosion resistance of the current collector could not be maintained. Thus over the film and corrosion resistance conductive material film -? P b 0 ₂ plated it is necessary to perform the operation process after such an applied.

Therefore, the present inventor has argued that sputtering methods and Using the method such as a plasma CVD method, even cheap easily processed low melting point material such as lead, covering the high melting point conductive ceramic having a good crystallinity and conductivity, for example, the S N_〇 ₂ We noticed that it was possible and confirmed that. By applying this surface treatment, the corrosion resistance of the positive electrode current collector was dramatically improved. The thin film produced by such a film-forming method has very few defects such as cracks, and its adhesion to the substrate is much larger than that produced by the conventional film-forming method of precipitating from the liquid phase. , as in the prior art / -? P b 0 ₂ plated step after extra, such that it is not necessary clarified and Natsuta.

Basically, it is effective to apply a current collector having been subjected to the surface coating treatment shown in the present invention in various battery systems. Taking lead batteries as an example, lead batteries have long been used as secondary batteries in terms of cost, safety and reliability, but new types of batteries (nickel-metal hydride, L i_ion etc.) has the disadvantage of lower energy density.

The reason is that, in addition to the low theoretical energy density, lead, which is the electrode plate of lead-acid batteries, gradually corrodes and degrades to lead dioxide over the life of the battery. It was necessary to secure the volume of the conductor over a certain amount, which resulted in the electrode plate becoming thick and heavy.

In addition, the thicker the electrode plate, the worse the diffusion of the electrolyte into the back of the electrode plate, and the lower the utilization rate of the active material. It is also known that it is good to lower the specific gravity of the electrolyte in order to improve the corrosion resistance of the positive electrode current collector, but this also makes the diffusion of the electrolyte worse, which is a factor that lowers the utilization rate of the active material. I was As the utilization rate of the active material decreases, a larger amount of the active material is required to obtain the required electric capacity, and the electrode plate becomes heavier and the energy density further decreases. The necessity of countermeasures against corrosion degradation of the positive electrode current collector is a major cause of further lowering the actual energy density of lead batteries with low theoretical energy density.

Based on the above, the use of a current collector coated with a conductive ceramic as described above eliminates the need to use an unnecessarily heavy current collector base material and uses a high-density electrolytic solution. To improve the practical energy density Become.

However, current collectors that have been surface-treated with conductive ceramics do not undergo a chemical bonding reaction between the current collector and the active material during the aging process, unlike conventional lead-acid batteries, and the current collector and the active material do not. The current collector is separated from the active material by physical force, such as gas generation during charging, expansion and contraction of the active material due to charge and discharge, or external vibration. Therefore, there is a possibility that the function as an electrode plate is lost.

In addition, increasing the specific gravity of the electrolyte or thinning the electrodes to improve the diffusion of the electrolyte and increase the utilization rate of the active material to increase the energy density dramatically increases the corrosion resistance. Although this is possible with an improved current collector, if the current collector is made thinner to reduce the weight of the battery and its volume is made smaller, the cross-sectional area of the current-carrying part becomes smaller, and the voltage due to the current collector resistance There was a concern that discharge performance would be adversely affected, for example, the drop would increase, the active material would be used unevenly, and the utilization rate would decrease.

In addition, as the size of the storage battery increases, the size of the straps and poles that conduct electricity from the electrode plates to the terminals also increases, causing an increase in weight.

SUMMARY OF THE INVENTION The present invention has been made under the above-mentioned background, and a current collector is formed by coating a current collector base material with a highly adhesive conductive ceramic thin film by a recent thin film manufacturing technique. Has improved corrosion resistance. As a result, it is possible to use a high-density electrolyte while reducing the weight of the current collector, and as a result, the utilization rate of the active material is increased, and a long-life, high-energy storage battery can be realized. Was. Furthermore, an active material is placed on the current collector surface, and a predetermined amount of compressive force is applied to the current collector surface in a direction perpendicular to the current collector surface to maintain electrical contact. As a part of the exterior, it has a structure that combines the functions of the current collector, the battery exterior, and the connection terminal, so that the strap / pole of the storage battery can be omitted. As a result, the weight and cost of the strap and poles are reduced, and there is no risk of abnormal corrosion, etc., and a simple, reliable, inexpensive, and high-performance storage battery and a manufacturing method thereof can be provided. . Invention disclosure>

The current collector for a storage battery according to the present invention is characterized by the following.

(1) A conductive ceramic thin film is formed on the surface of the current collector base material.

(2) The conductive ceramic thin film is formed on the surface of the current collector substrate by a step of precipitating from the gas phase.

(3) The step of depositing from the gas phase is a sputtering method.

(4) The step of depositing from the gas phase is a plasma CVD method.

(5) The material constituting the current collector base material is a metal or a metal alloy selected from lead, lead alloy, tin, tin alloy, bismuth or bismuth alloy.

(6) The material constituting the current collector base material is a conductive polymer.

(7) Sn0 ₂ to be used as the conductive ceramic.

(8) with respect to the conductive ceramic Sn0 _2, Sn and a range of 0. 5mo le% ~8mo le% by the total number of moles of Sb and this was for the additional inclusion of S b compound.

(9) the relative conductive ceramic S n0 _2, that the additional inclusion in the scope of 7mo le% ~60mo le% of F with respect to the total number of moles of S n and F.

(10) wherein T i S i ₂ as conductive _{_{ceramic, T i 5 S i 3,}} TaS i 2, T a 5S i 3, NbS i 2, Nb 5 using any of the silicon compound S i _3. Storage batteries using these current collectors are characterized as follows.

(11) Use the current collector described in (1) to (9) in the lead storage battery.

(12) Use the current collector specified in (10) in a lead storage battery.

(13) A storage battery using the current collector for a storage battery according to any one of (1) to (10), wherein an active material is disposed on a surface of the current collector, and the active material is disposed in a direction perpendicular to a surface of the current collector. X 10 ^⁴ ~2 0 X 10 ⁴ that a structure to maintain the compressive force of P a.

(14) In the storage battery according to (13), a positive electrode active material is provided on one surface of the current collector for a storage battery, and a negative electrode active material is provided on the other surface to form a bipolar electrode. The battery has a bipolar battery type structure in which a plurality of the electrodes are stacked via a separator for holding an electrolyte with the negative electrode active material surface facing the negative electrode active material. (15) The storage battery according to (13), which has one or two current collectors for a storage battery in which the active material is provided on one side and the active material is not provided on the other side. The structure shall be such that the surface on which no active material is provided is at least part of the exterior of the storage battery.

The method of manufacturing a storage battery according to the present invention is characterized by the following.

(16) A method for producing a lead-acid battery as described in (11), wherein after the electrolyte is injected according to the thickness (A micron) of the conductive ceramic coating layer, the following formula is used. Start chemical formation within T minutes).

T (min) ≤ 19.21 og ₁₀ A (micron)

(17) In the method for manufacturing a lead-acid battery described in (16), the electrode plate is to be formed in a state where the voltage of the battery is controlled to 1.0 V / cell or more within T minutes after the electrolyte is injected. .

(18) In the lead-acid battery manufacturing method described in (16) or (17), the battery voltage is controlled to 1.0 V / cell or more for at least one hour after the start of formation. The formation of electrode plates.

(19) In the method for manufacturing a storage battery using the current collector for a storage battery described in (6), the current collector is joined to a plastic battery exterior body by heat welding.

FIG. 1 is a schematic view showing a cross section of a positive electrode current collector according to the present invention,

Figure 2 is a characteristic diagram showing the relationship between S b amount and film resistivity to S n 0 ₂ thin film,

Figure 3 is S n0 characteristic diagram der 4 shows the relationship between the F amount and film resistivity to ₂ thin film, characteristic diagram showing the relationship between the thickness and the allowable resistivity of the conductive ceramic thin film And

Fig. 5 is a characteristic diagram showing the transition of the terminal voltage during the oxidation test.

FIG. 6 is a characteristic diagram showing the amount of corrosion of the Pb electrode after the oxidation test. FIG. 7 is a characteristic diagram showing discharge characteristics,

FIG. 8 is a schematic cross-sectional view showing an example of the configuration of a lead-acid battery using a conductive ceramic for the positive electrode.

Fig. 9 is a characteristic diagram showing the transition of the discharge capacity during the cycle life test, and Fig. 10 is a schematic cross-sectional view showing an example of increasing the voltage of a lead-acid battery using conductive ceramic for the positive electrode. Yes,

FIG. 11 is a schematic cross-sectional view showing an example of increasing the capacity of a lead-acid battery using a conductive ceramic for the positive electrode.

FIG. 12 is a schematic cross-sectional view showing a configuration of a bipolar lead-acid battery using a conductive ceramic for a positive electrode.

The first 3 figure is a characteristic diagram showing the relationship between P B_〇 ₂ amount after the chemical conversion and conversion limit voltage, the first 4 figures indicate the relationship between the corrosion layer thickness after the oxidation test and chemical limit voltage It is a characteristic diagram,

Fig. 15 is a characteristic diagram showing the relationship between the time from injection and the start of chemical formation and the thickness of the corroded layer.

The first 6 is a characteristic diagram showing the relationship between the time until S n 0 ₂ layer thickness and chemical starting limits which S n 0 ₂ layers is not dissolved.

Reference numerals in the figure, 1 denotes a positive electrode current collector base material, 2 denotes a conductive ceramic, 3 denotes a positive electrode active material, 4 denotes a negative electrode current collector, 5 denotes a negative electrode active material, 6 denotes a separator, and 7 denotes an exhaust hole. Reference numeral 8 denotes a plastic battery case, 9 denotes a connection plate, and 10 denotes a bipolar electrode.

Hereinafter, the present invention will be described in more detail with reference to examples.

[Example 1]

FIG. 1 is a diagram showing a cross section of a positive electrode current collector according to the present invention, wherein 1 is a current collector base material using lead which is a low melting point metal, and 2 is a conductive ceramic (SnO _2). ). Film of the thin film, and have use a target having the same composition as the material to be cane prepared _{(S n 0 2), 0} . 7 5 keep using the RF sputtering apparatus in A r gas cut ink in P a became. The substrate temperature during film formation was 120 ° C, which is sufficiently lower than the melting point of lead of 327 ° C. In this example, lead was used as the base material.However, even if the material had a low melting point, such as lead alloy, tin, tin alloy, bismuth or bismuth alloy, and had been considered difficult to coat, the same structure was used. A current collector was obtained.

FIG. 2 is a diagram showing the result of measuring the resistivity of the formed thin film, and it can be seen that the film containing Sb in SnO ₂ has a lower resistivity. Also, when the Sb content was in the range of 0.5 mole% to 8 mole% with respect to the total number of moles of Sn and Sb, a good film having low specific resistance was obtained.

FIG. 3 shows the result of measuring the resistivity of a thin film containing F instead of Sb. It can be seen that the film containing F also has a lower resistivity. The F content was in the range of 7 mole% to 60 mole% with respect to the total number of moles of Sn and F, and a good film with low specific resistance was obtained.

FIG. 4 is a characteristic diagram showing the result of examining the relationship between the thickness of the thin film and the allowable resistivity. In this figure, the current density is 10 OmAZcm ² and the voltage drop is 1 mV or less. This is a current density equivalent to 1 CA or more (C: rated capacity) in a practical storage battery, and a voltage drop of 1 mV or less has little effect on discharge performance. From these figures, Sn0 ₂ film thickness, it can be said that there is no influence on the battery performance if 100 microns or less. In addition, if the film contains Sb or F, the voltage drop can be further suppressed, and the film thickness can be increased to reduce defects such as pinholes in the conductive ceramic coating film, thereby improving reliability. Is possible.

Lead and titanium using the current collector substrate, prepared on the electrode a thin film of S n 0 ₂ having a thickness of 15 zm was formed by the above-mentioned sputtering thereon, the electrode not covered, it on its applying it paste active material for a lead storage battery is subjected to ordinary chemical conversion, after the specific gravity of an electrolyte sulfuric acid was adjusted to 1. 280 anode oxidation test at a constant current of 20 mA / cm ² Was done. Figure 5 shows the voltage transition during the test. Uncoated titanium-based electrodes showed remarkably high resistance at an early stage due to passivation of the substrate surface, and could not maintain their function as electrodes. Sn0 T i electrodes coated with ₂ had no problem at all to the voltage behavior even if 600 hours oxidation test, Even after disassembly inspection after the test, no deterioration of the S ηθ ₂ layer was observed. On the other hand, Pb-based electrodes could not maintain their function in a short time without coating. However, since it was not coated, lead, the base material, was significantly corroded.

Fig. 6 shows the amount of corrosion of the lead electrode measured after 600 hours of anodic oxidation test in Fig. 5. I understand.

Figure 7 is a graph showing the discharge characteristics when the current density was changed between the coated and uncoated electrodes when Pb was the current-collector base material. There was no difference due to the effect of the voltage drop due to the resistance of the covering film.

Also, this time, Sn0 ₂ and was used electrodes which were formed by sputtering Pb collector _{surface, T i S i 2, T} i 5 S i 3, TaS i 2, Ta 5 S i 3, NbS i _2, Nb 5 S i either silicon compound ₃ P b surface sputtering evening also to form a thin film having a thickness of the electrode of 10 microns was prepared by the ring, has been tested as described above, as with coated with S n0 _2, little corrosion, there is a significant effect on the corrosion resistance, the difference was also not in discharge performance.

Although the sputtering method is used in the present embodiment, the same effect can be technically obtained by using the plasma CVD method.

[Example 2]

10 micron thick Sn0 _2, to the surface of the 0. 5 mm thickness of Pb sheet over preparative formed on the surface so the positive electrode current collector by sputtering, by applying a positive electrode paste for a lead battery, typically of the negative electrode A negative electrode paste is applied on the Pb sheet, and a glass mat separator for a retainer-type sealed lead battery is assembled between the electrodes with various types of pressing force. The battery shown in Table 1 was assembled to produce a sealed lead battery with a capacity of about 0.25 Ah. As shown in Fig. 7, the surface of the current collector of both electrodes where the active material is not disposed serves as a part of the battery exterior, and also serves as a terminal for extracting current. The Pb sheet not form a S N_〇 ₂ as compared also manufactured a conventional sealed lead battery is used as it is, and subjected to the test. Table 1 Test batteries

These batteries were discharged at room temperature with a current of 0.6 CA for 1 hour, and subjected to a charge / discharge cycle test of a pattern of charging for 4.1 hours with a current of 0.2 CA. Figure 8 shows the change in discharge capacity during the life test.

The conventional sealed lead battery reached its life in about 500 cycles, but the capacity of the sealed lead battery of the present invention, which was compressed at 40 to 200 kPa, did not decrease at 800 cycles. However, the capacity of the A cell with low compression force (20 kPa) decreased very quickly at 100 cycles. When disassembled, the positive electrode active material was separated from the current collector, so the compression force was low, and the resistance at the interface between the current collector and the active material and the internal resistance of the battery increased during the cycle. It is considered that the capacity decreased. In addition, the capacity of the sealed lead battery E-cell manufactured at a high pressure of 40 OkPa decreased after 300 cycles, but when disassembled, the active material penetrated into the glass mat and a short circuit occurred. For compression was too strong, is Pb_〇 ₂ particles or P b particles as an active material, it seems to have One been penetrate into the small pores of the separator Isseki.

From the above results, Pb and to form a Sn0 ₂ on the collector surface as a base material, the positive electrode plate carrying thereon an active material thereon, with a current collector lead that does not cover the conventional Sn0 ₂ in the positive electrode Pb surface is coupled to P b 0 ₂ chemically a positive electrode active material is oxidized if, but for this than the surface S n0 ₂ is poor adhesion between to form the current collector and the active material However, the compression force needs to be increased, and if the compression force is too high, a short circuit will occur. Therefore, the compression force must be limited to 40 to 200 kPa.

In this example, the positive electrode plate formed by applying the active material to the current collector was used. Even if a pellet of the active material separately prepared was prepared and the collector was brought into contact with the current collector at a predetermined pressure, the result was the same.

Further, in the present embodiment uses the S n0 ₂ to electrically conductive ceramic as a corrosion resistant _{coating, T i S i 2, T} i 5 S i 3 shown in Example _{_{1, TaS i 2, Ta 5}} S i _{_{3, Nb S i 2, Nb}} 5 S i adhesion is poor between the active material even if any of the silicon compound _3, required compression force was the same as for S n0 _2.

In this example, the 2V battery shown in FIG. 8 was manufactured. However, as shown in FIGS. 10 and 11, it is not possible to stack a 2V battery to manufacture a high-voltage or high-capacity module battery. Easy. Be in this cell for cheaper almost becomes _c Thus manufacturing and parts costs not need a trouble of welding or connection of lead alloy each other at the required der ivy electrode plate group upper when a high voltage in a conventional lead battery And high output performance can be obtained because there is no voltage drop at this connection. At the same time, the weight of the connection can be reduced.

If the current collector coated with a conductive ceramic according to the present invention is used for the positive electrode, a bipolar battery can be realized because the current collector basically does not corrode. As shown in Fig. 12, a bipolar battery can be manufactured by applying a positive electrode and a negative electrode active material to both sides of a single current collector and stacking a large number of these electrode plates through a separator. Battery for voltage applications. A battery using such a single electrode plate having a positive electrode / negative electrode active material is called a bipolar battery. Conventionally, the positive electrode current collector also had a short life due to corrosion in this battery. Therefore, in order to extend the life, the electrode plate was thick and heavy, and the energy density was low. In order to connect a large number of cells, it took time and effort to weld and connect the lead alloys at the top of the electrode group. However, in the storage battery according to the present invention, since the positive electrode plate does not corrode, a light and thin electrode plate can be used, and a current flows in the vertical direction of the current collector surface having a large area of the thin current collector. Even if the current collector is thin, the thinner the current collector, the smaller the voltage drop of the current flowing in the thickness direction, and the lighter the current collector, the lower the output performance. High voltage can be achieved simply by stacking the cells in order, so there is no need for welding or wiring. That is, a bipolar battery can be manufactured using the technology of the present invention. This would make it possible to supply very inexpensive, long-life, high-energy-density batteries.

[Example 3]

Previously result we have experimented, the Sn0 ₂ layer was formed on the current collector surface, 1. become a voltage less than 0V, it was found that would eluted in the sulfuric acid. This potential is reached during the initial formation of the electrode plates during the manufacture of lead-acid batteries. The electrode plate of the lead storage battery shows a very low voltage of 0 V to 0.5 V after sulfuric acid injection.

In the present invention, after the injection sulfate, immediately by the voltage of the battery above 1. 0V, it can suppress the elution of S n0 ₂ of the current collector surface.

On the other hand, when formation is performed at a high voltage, gas is generated during the formation on the surface of the SnO ₂ , and the adhesion between the active material and the current collector is lost, and the internal resistance of the battery increases. In the present invention, by limiting the voltage of the conversion initial 1 hour below 2 V, it was found to be maintained the adhesion to the S n0 ₂ and the active material.

First, after forming the S n 0 ₂ to various thicknesses by sputtering the pure P b sheet surface of thick 0. 5 mm, and the active material for the conventional lead battery to prepare a by coating the positive electrode plate. This electrode plate was combined with a negative electrode plate for a normal lead battery and a fine glass fiber separator for a sealed lead battery to produce a lead battery with a capacity of about 0.25 Ah. For comparison, to prepare a Traditional lead battery using the positive electrode plate for a conventional lead battery which is not to form a Sn0 ₂ to Pb sheet surface was subjected to the test.

These batteries, conducted various varied chemical conversion time and voltage until after electrolyte injection Kasei, after measuring the Pb0 ₂ amount after the chemical conversion, in 0. 05 CA current performed 120 hours § nodes oxidation test, the test The amount of corrosion afterwards was measured and compared. Table 2 shows the test battery contents.

The formation is performed in two steps, and the first step is the formation in which the voltage is limited. Table 2 Test conditions and test battery contents

The test results are shown below. First, in a battery using a positive electrode plate with an Sn0 ₂ layers of 10 microns is formed on the surface, when changing the voltage and time of the first chemical, the PbO ₂ amount and thickness after conversion 13 and 14 Shown in In this test, the time from the start of injection to the start of chemical formation was 0 min. From Figure 12, the voltage of the first chemical conversion was often P b 0 ₂ quantity when below 2 V. The P b 0 ₂ quantity when the voltage exceeds 2 V was small, when chemical conversion initial voltage is too high, the conversion efficiency for gas generating intense in the field plane of the Sn0 ₂ and the active material of Pb seat surface It seems that it is decreasing. Also, when the first formation time was set to 1 hour or more, the amount of PbO ₂ was large.

The measured corrosion thickness after the oxidation test in Fig. 13 indicates that if the first formation voltage is lower than IV, the Sn0 ₂ layer may be melted, and the corrosion layer thickness is Sn0 ₂ This was the same as a conventional lead battery that was not formed on the body surface. However, when formed at a voltage of IV or higher, almost no corrosion occurred.

From the above result, the voltage of the first chemical conversion it should be more than 1 V, to further improve the P b 0 ₂ amount to a voltage below 2 V, it should be the time to 1 hour or more Kotogawa won. Next, when the first chemical conversion was performed under the conditions of 1 Vx 5 h, the relationship between the thickness of the Sn0 ₂ layer and the time from injection to the start of chemical formation, and the thickness of the corroded layer in the oxidation test Is shown in Figure 15. From the figure, when the Sn ₂ layer was thickened and the time from the injection to the start of chemical formation was short, almost no corrosion occurred in the oxidation test. On the other hand, when the Sn ₂ layer was thin or when the time until the start of chemical conversion after injection was long, corrosion after the oxidation test increased. In order to clarify the conditions under which the amount of corrosion is reduced, the critical formation start time with less corrosion was plotted again in Fig. 16 against the Sn0 ₂ layer thickness. From this figure, it can be seen that in order to suppress the dissolution of the Sn ₂ layer during chemical formation and improve the corrosion resistance, the electrolyte is injected after the injection according to the thickness of the Sn ₂ coating layer (A micron). The formation should be started within the time (T minutes) of the following formula.

T (min) <19.2 21 og ₁₀ A (micron) In all of the above examples, metal Pb or Ti was used for the base material of the positive electrode current collector, but not necessarily. It does not need to be metal, and a conductive polymer to which a conductive filler is added may be used. At the same time, if a conductive polymer with a conductive filler added is used for the negative electrode current collector, the storage battery can be assembled by joining the positive and negative electrodes to the plastic battery outer package by heat welding, eliminating the need for an adhesive. Thus, it becomes possible to commercialize a cheaper sealed lead battery. Industrial applicability>

As described above, according to the current collector subjected to the conductive ceramic coating treatment according to the present invention and the storage battery maintaining a predetermined required amount of compressive force without the use of connecting parts using the same, the conventional thin film of the corrosion-resistant conductive material is used. The problem is that the assembly cost is high, as in the case of an electrode coated with aluminum, the adhesion between the current collector and the active material is poor, and the function cannot be maintained, or various problems that lead-acid batteries have And a light and thin lead-acid current collector for lead-acid batteries with excellent corrosion resistance and a high-performance lead-acid battery with long life, high energy density, high reliability and low cost Since it can be provided, its industrial value is extremely large.

Claims

The scope of the claims

1. A current collector for a storage battery, wherein a thin film of conductive ceramic is formed on the surface of a current collector base material.

2. The current collector for a storage battery according to claim 1, wherein the thin film of the conductive ceramic is formed on a surface of the current collector base by a step of precipitating from a gas phase.

3. The current collector for a storage battery according to claim 2, wherein the step of precipitating from the gas phase is a sputtering method.

4. The current collector for a storage battery according to claim 2, wherein the step of depositing from the gas phase is a plasma CVD method.

5. The material according to claim 1, wherein the material constituting the current collector base material is a metal or metal alloy selected from lead, lead alloy, tin, tin alloy, bismuth or bismuth alloy. 5. The current collector for a storage battery according to any one of the items 4 to 4.

6. The current collector for a storage battery according to any one of claims 1 to 4, wherein a material constituting the current collector base material is a conductive polymer.

7. The electrically conductive ceramic as S n0 ₂ the battery current collector stomach Zureka 1 wherein the range of the first to sixth preceding claims using.

8. respect to the conductive ceramic Sn0 _2, the scope of the claims, characterized in that for the additional inclusion of Sb compound in the range of 0. 5mo le% ~8mo le% relative to the total number of moles of S n and Sb Item 7. A current collector for a storage battery according to Item 7.

9. respect to the conductive ceramic Sn0 _2, Sn and F 7mo le% ~60mo range 7 or 8 the preceding claims, characterized in that for the additional inclusion of F in the range of le% relative to the total number of moles of The current collector for a storage battery according to the above.

10. use the T i S i ₂ as conductive _{_{ceramic, T i 5 S i 3,}} T aS i 2, T a 5 S i 3, Nb S i 2, any of the silicon compounds of Nb ₅ S i ₃ The current collector for a storage battery according to any one of claims 1 to 6, wherein

1 1. A lead storage battery using the current collector for a storage battery according to any one of claims 1 to 9.

12. A lead storage battery using the current collector for a storage battery according to claim 10.

13. A storage battery using the current collector for a storage battery according to any one of claims 1 to 10, wherein an active material is disposed on a surface of the current collector, and a surface of the current collector is provided. storage battery, characterized in structure to maintain the compression force of ^{4 X 1 0 4 ~2 0 X} 1 0 4 P a in the vertical direction.

14. In the storage battery, a positive electrode active material is provided on one surface of a current collector for a storage battery, and a negative electrode active material is provided on the opposite surface to form a bipolar electrode. The positive electrode active material surface and the negative electrode active material surface 14. The storage battery according to claim 13, wherein the storage battery has a bipolar battery type structure in which a plurality of the electrodes are stacked via a separator holding an electrolyte.

15. The storage battery has one or two current collectors for a storage battery on which an active material is provided on one side and no active material is provided on the other side, and the active material of the current collector is provided. 14. The storage battery according to claim 13, wherein the storage battery has a structure in which the non-surface is at least part of a storage battery exterior.

16. The method for producing a lead-acid battery according to claim 11, wherein the electrolyte is injected according to the following formula according to the thickness of the conductive ceramic coating layer (A micron). A method for producing lead-acid batteries, characterized in that chemical formation starts within the time (T minutes).

T (min) ≤ 19.2 1og ₁₀ A (micron)

17. The method for manufacturing a lead-acid battery according to claim 16, wherein the voltage of the battery is controlled to a voltage equal to or higher than 1.0 VZ cell within T minutes after injecting the electrolyte, and the electrode plate is formed. A method for producing a lead storage battery, comprising:

18. The method for producing a lead storage battery according to claim 16 or 17, wherein the voltage of the battery is controlled to a voltage of 2.0 V or less for at least one hour after the start of the formation. A method for producing a lead storage battery, comprising forming an electrode plate in a state.

19. The method for manufacturing a storage battery using the current collector for a storage battery according to claim 6, wherein the current collector is joined to a plastic battery exterior body by heat welding. Manufacturing method.