RU191063U1 - Chemical current source with thin-film collector - Google Patents

Abstract

The utility model relates to the design of a chemical current source (CIT) with a cathode made using thin-film technology. The authors solved the problem of increasing power and fire and explosion safety, reducing heat release in the HIT by reducing the electrical resistance of electrode materials. The stated technical problem is solved by reducing the electrical resistance of the contact of the collector - the chemically active layer and by more than an order of magnitude lowering the electrical resistance of the chemically active layer due to the manufacture of electrode materials using thin-film technology. An increase in the power of HIT is provided by the design of electrode materials, which allows one to develop the working surface of the electrodes. As a result of a decrease in the internal resistance of HIT, its fire safety increases.

Description

The utility model relates to the design of a chemical current source (CIT) with a collector made using thin-film technology. The authors solved the problem of increasing power and fire-explosion safety, reducing heat release in HIT by reducing the electrical resistance of electrode materials. The stated technical problem is solved by reducing the electrical resistance of the contact of the collector - the chemically active layer and by more than an order of magnitude lowering the electrical resistance of the chemically active layer by manufacturing electrode materials using thin-film technology. An increase in the power of HIT is provided by the design of electrode materials, which allows one to develop the working surface of the electrodes. As a result of a decrease in the internal resistance of HIT, its fire safety increases.

Known are the designs of rolled lithium current sources, the electrical connection of the electrode blocks of which with the terminals of the HIT carry out the current leads of the electrode plates coming out of the ends of the roll, the collector, to which the current leads are connected, and a pressure lead passing through the cover of the current source. Current leads are often made in the form of narrow metal strips located at the ends of the plates or along their entire length at certain intervals (Pat. 6376121 (USA), IPC ⁷ H01M 6/10. Spirally wound lithium secondary cell having a plurality of current collector tabs and method of manufacture / Inomata Hideyki, Nakanishi Naoya, Nogami Mitsuzo, Yonezu Ikuo, Nishio Koji; Sanyo Electric Co., Ltd. - No. 09/485172; Declared 09/28/1998; Published on 04/23/2002; Prior. September 30, 1997, No. 9 - 266171 (Japan); NPK 429/94). The edges of the strip plates protruding at the ends of the roll block are also used as current leads (Pat. 4322484 (USA), MKI H01M 6/10, NKI 429/94. Spiral wound electrochemical cell having high capacity / Sugalski Raymond K .; General Electric Co - No. 187743; Declared September 16, 1980; Published March 30, 82). The collectors are placed above the coil block of electrodes under the cover or under the electrode block at the bottom of the HIT housing, or the collector of one of the electrodes is the inner surface of the housing or cover of the current source. The collectors are connected to the HIT terminals, one of which may be a housing or a cover of a current source, and the other is a hermetic outlet passing through the cover of a current source, electrically isolated from it.

The described HIT designs have an increased explosion hazard during overcharging, associated with the location of the electrode collectors above the roll block under the cover or under the electrode block at the bottom of the housing. This increases the likelihood of internal short circuits initiating a CHIT explosion.

The closest in technical essence is patent No. 23355828 (Pat. 2335828 (Russia), IPC H01M 6/14, H01M 10/40. Lithium chemical current source with a coil electrode assembly. - Application No. 2007113240/09, filed April 9, 2007; Published on October 10, 2008, Bulletin No. 28). The invention relates to cylindrical chit with rolled electrodes of opposite polarity, containing several tape electrode plates separated by separators. The collector of the positive electrode is made in the form of a tape metal plate, part of which is rolled into a cylinder, electrically connected to the hermetic outlet, and is located in the core of the roll, and the rest is curved along the thickness of the coil of electrodes. Along the curved part of the collector are the inner ends of all plates of the electrode assembly, and the outer ends of the plates are located on the periphery of the roll. The inner ends of the plates of the positive electrode are electrically connected to the collector, and all ends of the plates of the negative electrode located on the periphery of the roll are connected by current leads to the lid of the HIT. The last plate of the negative electrode is held by a grip of insulating material connected to the curved part of the collector of the positive electrode, and covers the roll around the perimeter.

The described HIT design is more explosion-proof during overdischarges than HIT, in which the electrode collectors are located above the roll block under the cover or under the electrode block at the bottom of the housing. This is due to the fact that the collector of the positive electrode located inside the coil reduces the likelihood of internal short circuits initiating an explosion of HIT and is a heat sink that reduces overheating of the internal parts of the coil of electrodes.

However, the described design of HIT with a coil block of electrodes, consisting of several tape plates, has certain disadvantages that limit the power of current sources and contribute to the occurrence of internal fires. At high load currents under conditions of overcharging, a heating of the ChIT casing to 180 ° C and higher is observed. As shown by the autopsy of the HIT after switching off the load, the indicated temperature increase leads to burning of parts of the strip plates of the negative electrode located on the periphery of the coil of electrodes.

In the patented HIT, solutions are proposed that reduce the release of thermal energy during operation and hazardous heating during discharge and overcharge for a given time and capacity.

The goal in HIT is achieved by the fact that a lithium chemical current source with a roll electrode assembly, containing a cylindrical metal case, a metal cover, a positive electrode pressure lead through the cover, and a roll electrode block including a negative electrode of two or more tape plates, tape separators , a positive electrode of two or more tape plates, the inner ends of which are electrically connected to a collector made in the form of a metal strip, some of which th rolled into a cylinder and located in the middle of the coil coaxially with its longitudinal axis, and the rest of the collector is curved along the thickness of the coil of electrodes, and all ends of the plates of the negative electrode are located on the periphery of the coil and are connected to the cover, while one end of the tape collector of the positive electrode is connected to with a pressure seal, and the other with a grip of an insulating material holding the negative electrode plate, all the ends of the negative electrode plates located on the periphery ulon are electrically connected to the collector of the negative electrode made of a metal plate located on the outer surface of the coil of electrodes and connected by a current outlet with a cover, characterized in that the electrodes are made of porous roll material, Busofit-type fabric is used as the porous roll material, the collector is made of in the form of a thin layer of titanium with a thickness of 6 μm deposited on a porous matrix of a porous roll material by spraying, current collectors with the aim of increasing the chemical They are coated with titanium nitride 0.2 microns thick.

A lithium chemical current source with a rolled electrode assembly consists of a metal cylindrical body 1 in which a rolled electrode assembly 2 is located, insulated from the bottom and cover 3 by gaskets of insulating material 4 (Fig. 1).

The cylindrical part of the positive electrode current lead 5 connected to the pressure lead 6 passing through the metal cover 3 and isolated from it by the molten glass washer 7. The same current leads 8 located at the outer ends of the negative electrode plates are connected to the inner surface of the cover 3.

The rolled electrode assembly 2 consists of rolled-up positive electrode current lead 5, prefabricated electrode plates of positive electrodes 9 and prefabricated electrode plates of negative electrodes 10 wrapped with tape separators 11 (Fig. 2).

The prefabricated electrode plate of the positive electrode 9 (Fig. 3) consists of a carbon fabric of the Busofit type 12, on which a collector 13 is deposited by spraying on one side. The collector 13 is a layer of titanium with a thickness of 6 μm, which is coated on top with titanium nitride with a thickness of 0.2 μm.

The prefabricated electrode plate of the negative electrode 10 (Fig. 4) consists of a carbon fabric such as Busofit 12, on which a collector 13 is sprayed on one side. The collector 13, as in the positive electrode assembly electrode plate, is a titanium layer 6 μm thick, which is coated on top with titanium nitride 0.2 μm thick. A current lead 8 is glued to the end of the negative electrode collector using a silver paste. Then the entire workpiece is wrapped with a tape separator 11 to accumulate electrolyte and prevent a short circuit between the positive and negative plates.

The last plate of the negative electrode 15 (Figs. 2 and 5) differs from the others by the presence of a grip of insulating material 16, which is used to attach a positive electrode to the end of the current output 5. The current lead of the positive electrode 5 is a tape metal plate made of titanium foil and coated with titanium nitride, to one part of which are connected the collectors 13 of positive electrodes located on the inner ends of the electrode strips directed to the core of the roll, and the other part remains free.

The size ratio of these parts of the collector depends on the total number of electrode plates and the diameter of the coil core free of electrodes (Fig. 2). Between the plates of the positive electrode 9 there is an appropriate number of plates of the negative electrode 10, wrapped with tapes of the separator 11. Current collectors of the plates of the negative electrodes 13 are located at their outer ends peripheral to the roll (Fig. 2). The electrodes are arranged so that the last of the free part of the current output 5 is one of the plates of the negative electrode 15, its end facing the current output of the positive electrode 5 is held by a grip of insulating material 16 attached to the end of the current output (Fig. 5).

Introduced proposed changes in the design of HIT and the use of electrode materials manufactured by thin-film technology reduces the resistance of contact transitions of the chemically active layer - collector by 10 or more times. Due to this, the release of thermal energy during operation and the likelihood of hazardous heating during discharge and overcharge for a given time at a given capacity are reduced. Thus, the considered design of the HIT has a higher reliability compared to the prototype with the same nominal values of capacity and operating time.

The above information allows us to conclude that the proposed chemical current source with a thin-film collector provides claimed advantages over the prototype.

The analysis of the prior art by the applicant has established that:

analogues, characterized by sets of essential features that are identical to all the features of the claimed HIT, are absent, which indicates the compliance of the claimed utility model with the condition of patentability "novelty";

the proposed HIT is industrially applicable to existing technical means and meets the criterion of "inventive step", since it does not explicitly follow from the existing level of technology.

Thus, the proposed technical solution meets the established conditions of patentability of a utility model.

Claims (1)

A chemical current source with a thin-film collector containing a cylindrical metal casing, a metal cover, a positive electrode pressure lead through the cover, and a coil block of electrodes including a negative electrode from two or more tape plates, tape separators, a positive electrode from two or more tape plates, the inner ends of which are electrically connected to a collector made in the form of a metal strip, part of which is rolled into a cylinder and located in the middle of the roll coaxial to its longitudinal axis, and the rest of the collector is located curvilinearly along the thickness of the coil of electrodes, and all ends of the plates of the negative electrode are located on the periphery of the coil and are connected to the cover, while one end of the tape collector of the positive electrode is connected to the hermetic outlet, and the other to capture from the insulating of the material holding the negative electrode plate, all ends of the negative electrode plates located on the periphery of the roll are electrically connected to the negative collector an electrode made of a metal plate located on the outer surface of the coil of electrodes and connected by a current outlet with a cover, characterized in that the electrodes are made of porous roll material, a carbon fabric of the Busofit type is used as a porous roll material, the collector is made in the form of a thin layer of titanium with a thickness 6 microns deposited on the porous rolled material of the electrode by spraying, current collectors with the aim of increasing chemical resistance are coated with titanium nitride with a thickness of 0.2 microns.

Images