JPS5840311B2 - dench - Google Patents

Description

[Detailed description of the invention] The present invention relates to batteries.

Conventionally, it has been confirmed that batteries using a large amount compound of graphite and fluorine, that is, an intercalation compound, as the positive electrode (hereinafter referred to as the cathode) and lithium metal as the negative electrode (hereinafter referred to as the anode) are useful as primary batteries (
(See U.S. Pat. No. 3,514,337).

However, although such batteries have a relatively high energy intensity, they have the significant disadvantage of being secondary batteries (ie they cannot be recharged).

In comparison, the batteries provided by the present invention not only often have a relatively high energy intensity, but can also be charged and discharged many times.

The present invention provides a battery that can be manufactured in either a charged or discharged state.

Next, the elements of the two types of batteries (referred to herein as a rechargeable battery and a discharge battery) will be described in detail.

■ Rechargeable battery cathode The cathode is a chalcogen compound of the formula MZx as the cathode active material, where M is titanium, Z is an element selected from the group consisting of sulfur, selenium, tellurium, and X is about 1. Contains chalcogen compounds having a numerical value of 2 to about 2.05.

The cathode structure itself does not necessarily have to consist of a cathodically active material, but may be a structure consisting of, for example, carbon, copper, nickel, zinc, silver, etc., and a chalcogen compound deposited thereon.

Preferably, the cathode structure consists only of a chalcogen compound.

The cathode active material is a good electron conductor and thus acts as its own current collector.

Preferably, the cathode active material is not miscible or diluted with electrochemically inert materials or other electrochemically active materials (chalcogen compound alloys (i.e., solid solutions)). chalcogen compounds are preferred).

The cathode can be readily manufactured from individual or alloyed chalcogen compounds using known materials and techniques, ie, using polytetrafluoroethylene binders or nickel or copper mesh support structures.

Chalcogen compounds used as cathode active substances 1,
It may be any compound within the ranges mentioned above.

Z is preferably sulfur or selenium (particularly preferred sulfur) and X is preferably about 1.95 to about 2
．． It is a numerical value of 02.

A particularly useful cathode active material is titanium sulfide.

The anode Anode comprises as anode active substance a group 1a metal, a group 1b metal, a group 1Ia metal, a group 1a metal, a group 1a metal, a group 1Va metal, and mixtures of the above metals with each other or with other substances. and a mixture such that said metal can be electrochemically liberated from said mixture.

Suitable examples of the above-mentioned "other substances" are ammonia and amines.

Preferably, the anode active material is selected from the group consisting of Group 1a metals, magnesium, calcium, strontium, barium, copper, silver and zinc.

Particularly useful anode active materials are lithium (most preferred),
potassium and sodium.

In the present invention, boron, carbon, silicon, and germanium are not considered useful as anode active materials.

As in the case of the cathode, the anode may be made solely of the metals mentioned above, or it may consist of a basic structure (for example made from materials such as copper, nickel, etc.) and an anode active material deposited thereon.

Electrolytes useful in the manufacture of electrolyte rechargeable batteries are those that do not chemically react with the anode or the cathode so that ions are transferred from the anode active material to the cathode active material or vice versa (depending on the discharge and charging stages, respectively). ), it must be thrown with something that can be moved.

The electrolyte may be present in pure state (solid, molten solid or liquid) or conveniently fermented in a suitable solvent.

Generally, the electrolyte material should consist of the same compound as that selected as the anode active material.

Thus, useful electrolytes are conveniently represented by the general formula LY, where Y is the cationic moiety selected from the same materials useful as anode active materials, and Y is the anionic moiety. For example, rogenides, sulfates,
These are nitrates, beta aluminas, fluorides, perchlorates, and rubidium halides.

Particularly useful electrolyte materials include LiPF6, Liclo4
, sodium beta-alumina, silver nitrate, silver rubidium iodide, copper sulfate, KCNS, LiCN5, etc.

The electrolyte may be present in the pure state (solid, molten solid or liquid) or may be conveniently present in a suitable oxidizing agent such as water, alcohols, ketones, esters, ethers, organic carbonates, organic lactones, organic It is present in fermented form in nitriles, nitrohydrocarbons, organic sulfoxides, and mixtures thereof.

If a fluid is used, the electrolyte salt will be in solution determined by the desired conductivity and chemical reactivity.

■ Discharge battery cathode When producing the cathode of a battery, it is advantageous to initially produce the battery in a discharged state.

It has now been found that if the cathode active substance consists of a large amount of chalcogen compound, the battery manufacturing technology becomes significantly easier and more economical.

Enlarged chalcogen compounds, especially fully enlarged chalcogen compounds, such as LiTiS2 or LiTaS2,
They are relatively sensitive to atmospheric conditions compared to the case where the anodic active substance consists of a bulk substance and the cathodic active substance consists of a chalcogen compound.

For example, when batteries are manufactured in a charged state, Group 1a metals such as lithium, sodium and potassium readily react with moisture and gases normally present in the atmosphere, forming oxides,
forming nitrides, hydroxides, carbonates, etc., thus forming 1a
Decreases the availability of group metal ions.

In such cases, cells with anode active materials typically must be manufactured in an inert atmosphere, such as argon, to prevent degradation of the anode active material.

In comparison, the cathode active material consists of a chalcogen compound that has been bulked up by the method described below; bulked up chalcogen compounds are relatively stable to atmospheric conditions and therefore can be used in cells in an inert atmosphere. Eliminates the need for manufacturing.

The enlarged chalcogen compounds utilized as cathodic active materials for the irradiation ponds are composed of the same metals mentioned above as the anode active materials (these metals or metal compounds are therefore
(a large source of ions) and the same chalcogen compounds mentioned above as useful as cathodic active materials.

However, in contrast to the anodic action that is useful for rechargeable batteries, mixtures of metals and other materials are unsuitable as scale species for discharge batteries.

On the other hand, the chalcogen compound may be an alloy of the chalcogen compound and another substance.

Various methods for preparing large quantities of chalcogen compounds are already known.

For example, the Journal of Chemica
i Physics % Volume 58, page 697 and below (
Published in 1973): German Patent Publication No. 2061162
Issue: National Bureau of St.
andards Special Publica
tion No. 364, page 625 and below (published in 1972): J ourralof the Less -
Common Metals, Volume 20, pages 121 and below (published in 1970): 5science No. 175, pages 884 and below (published in 1972): C, R-Aca
d, Sc, Paris, No. 276, pp. 1283 and below (19
(published in 1973).

In the case of an anode discharge cell, the anode is simply a current collecting structure (e.g. a wire, grid or foil) onto which a large amount of chemical species is deposited in the basic form (the deposition is the activation of the discharge cell). or during the charging phase).

When the catholytic agent consists of a fully bulked bulk chalcogen compound, a sufficient amount of the mesoscale species is generally available for deposition on the anode, and the anode has a complementary anolytic agent. There is no need to include it.

Of course, if desired, the anode may be deposited with an anode active substance (the anode active substance may be the same as that used in the rechargeable pond), but in this case:
The advantages of being able to manufacture the cell in air (compared to the disadvantage of having to manufacture it in an inert gas such as argon, for example) are reduced.

Examples of anode materials that are useful as substrates on which to deposit dimensional species during charging of a discharge cell include metals such as aluminum, copper, nickel, and the like.

Electrolyte The electrolyte consists of or consists of chemical species that do not chemically react with either the anode or the cathode and allow (during the charging phase) for large species of ions to migrate from the cathode agent and deposit on the anode. Consists of substances containing.

In general, the electrolyte used in the manufacture of discharge batteries may be any of the aforementioned materials that can be used as electrolytes in rechargeable batteries.

The following examples are intended to illustrate rechargeable and discharged batteries.

Example l - Rechargeable battery 9.22.9 titanium wire and 12.3.9 sulfur 1
Heated to 750°C for 8 days, then 6000C for 7 days in a sealed quartz tube.

2 g of the titanium disulfide powder thus treated was incubated at 900°C for 18 days with iodine as a transfer agent.

Heated at varying humidity of °C and then at 600'C for 2 days.

This resulted in the formation of a single pure crystal of titanium disulfide TiS2.

The 10m, 9 crystals were then tied to a copper wire and immersed in a saturated solution of vacuum distilled propylene carbonate and lithium hexafluorophosphate.

A 0.4 cfn x 2 cr/1 x 0.05 cm lithium meat was used as an anode.

All processing and cell testing was done in a helium atmosphere.

The voltage was initially about 3.0 volts at zero current drain.

When the cell was shorted, a current drop from about 10 milliamps/Cl112 based on the active cathode surface was observed.

As the discharge progressed, the open circuit voltage decreased.

Thus, the open circuit voltages for the cathode compositions LiO,25TiS2 and Li0.75 were 2.30 and 2.04 volts, respectively (corresponding to 25φ and 75V discharge conditions, respectively).

Recharging was accomplished by applying 4 volts to the battery.

Currents with different signs but the same numerical value and time were observed.

Example 2 - Rechargeable Battery 0.52 g of titanium disulfide powder was pressed onto a 0.5 inch diameter copper plate.

This was covered with filter paper as a separator and attached to a Teflon holder.

Several mils of a saturated solution of propylene carbonate and lithium hexafluorophosphate were injected into this holder.

Diameter 0.4X2. A lithium single anode of OXo, 05crrI was obtained.

Next, a copper plunger was firmly screwed into this Teflon holder.

Contact of the battery electrodes was made with a copper plate and plunger.

The initial open circuit voltage was 2.84 por.

At a discharge rate of 1/3 milliampere, the cell voltage ranged from 2.1-1.8 volts for several hours.

With a 1/3 milliamp recharge, the applied voltage remained in the 2.5-3.5 V range for several hours.

No deterioration of the thread was observed due to low-depth cycling of the battery.

Example 3 - Discharge battery Titanium disulfide powder o, s obtained as in Example 1
1. ! ? Lithium titanium sulfide Li1. ) TiS2 was prepared and left in a nitrogen atmosphere for several days.

Approximately 5 Qm, 9 Li1. □ TiS2 was crimped onto a copper plate.

The remainder of the battery was the same as that of Example 2.

The initial open circuit voltage of this cell was 1.87 volts.

Claims (1)

[Scope of Claims] 1 The following elements: (a) Group 1a metal, Group 1b metal as a negative electrode active substance;
Group metals, Group 1 Ia metals, Group NB metals, Group 1 Na metals, Group 1 Va metals, and mixtures of the aforementioned metals with each other or with other substances, wherein the aforementioned metals are electrochemically removed from the mixture. a negative electrode comprising a metal selected from the group consisting of: 0) as a positive active substance a chalcogen compound of the formula MZx, where M is titanium; Z is sulfur; Element selected from the group consisting of senone and tellurium: X is about 1.2 to about 2
．． and (c) does not chemically react with the negative electrode or the positive electrode;
an electrolyte that enables the transfer of ions from the anode active material to the cathode active material. 2 The following elements: (a) As a positive electrode active substance, the chemical species that are present in large quantities are group 1a metals, group 1b metals, group 1a metals, group NB metals, group 1a metals, and group 1a metals. A positive electrode containing an increased amount of a chalcogen compound, the chalcogen compound being a metal selected from the group consisting of: (b) a negative electrode having a substrate capable of depositing the chemical species to be enriched; c) an electrolyte that does not chemically react with the negative electrode or the positive electrode and is capable of electrochemically transporting ions of a chemical species in large quantities from the positive electrode active material and depositing them on the negative electrode. A battery.