JPH06502738A - high temperature cell battery - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] high temperature cell battery The second invention relates to a battery including a plurality of high temperature cells, and more particularly to a battery including a plurality of high temperature cells. The present invention relates to a conductive structural member used in a battery.

High temperature cells are cells that operate above ambient temperature, typically 100° C. or higher.

One example of a high temperature cell is a sodium/sulfur cell, whose operating temperature is 300°C. Between 400°C and typically 350°C.

interconnected cells required to provide the required energy storage capacity from a single cell. Many types of batteries are known, including arrays containing multiple cells.

Secondary batteries have been developed that can be recharged when depleted and have a relatively long lifespan. . These batteries can be used to start cars, forklift trucks, etc. Powered by electricity (powering vehicles, providing backup power for buildings and telephone switching equipment) It is used for supplying. Recently, sodium/sulfur type secondary These batteries are known for their light weight, high storage capacity, and considerable storage capacity. It has the advantage of fast recharging time. Furthermore, such batteries are cheap and abundant. It uses sodium and sulfur, materials found in abundance.

Unlike traditional lead-acid batteries, where an electrolyte - dilute sulfuric acid - separates the two solid electrodes, In a sodium/sulfur cell, a solid electrolyte - beta aluminum - connects two liquid electrodes, That is, the liquid sulfur and sodium electrodes are separated.

Such a sodium/sulfur cell is shown in FIG. This figure shows a partially removed cell. FIG. As shown in the figure, the cell is of right cylindrical shape, made of e.g. steel. , includes a case 1 containing a solid electrolyte cup 2 of beta alumina, cup 2 is of nat. The space between the case 1 and the cup 2 includes a sulfur electrode 4. . In use, the cell is hydrated so that the sodium and sulfur electrodes 3.4 are liquids. The temperature is maintained between 300°C and 400°C.

The open end of the cup 3 is sealed with an insulating disk 5 of alpha alumina, and the case 1 is sealed with a tubular seal. It is sealed with a copper disk 6.

Case 1 functions as a terminal for sulfur electrode 4, and sodium electrode 3 passes through disk 5. It includes an elongated metal current collector 8 extending along the axis of the case 1 . On disk 5, this The connector is connected to a central terminal disk 7 placed on disk 5. Necessary connections are welded Therefore, it is formed.

Forms an electrical connection between case 1 and cup 2 since sulfur is a non-conductor means must be provided to do so. This generally involves dipping the sulfur electrode 4 into sulfur. This is achieved by forming the carbon fiber mat as a carbon fiber mat.

In such a cell, the sodium and sulfur electrodes 3, 4 may be arranged in reverse. It is clear that this can be done.

To provide a battery capable of powering a vehicle, approximately 300 0 cells together so that the cells are arranged in series, as shown above. May need to be assembled. Series arrangement in individual arrays in parallel Connected and distributed! The arrays are connected in series.

In WO39100344 (Cloreed Silent Power Limited), Various configurations of batteries are disclosed, each with a single cell or bus Arranged between the plates! one or more arrays of serially arranged cells. Illustrations in this specification 2 is based on the above content, and includes the three points explained above with reference to Figure 1. Multiple series arrangements of cells 10 are shown. Adjacent cells in each placement The cables are separated by spacer members 11 and connected by conductive metal strips 12. ing. The cells are arranged in series in parallel between a pair of mild steel bus plates 13! been There is.

Each bus plate 13 has a hole 14 aligned with the central axis of the series arrangement of cells 10. Formed by a matrix. Lower cell 10 (as shown) in individual arrangement case 15, the center terminal of the upper cell 11 (as shown) in the individual arrangement The disks 16 are electrically connected to each adjacent bus plate 13 . this electricity The connection is made by a conductive metal strip welded to the case 15 or to the terminal disc 16 at its center. 17. The free end of the metal strip 17 passes through the aligned hole 14 , are welded to the side of the bus plate 13 remote from the cell 10.

In this way, the cells 10 are connected in series within each series arrangement, while the series arrangement They are connected in parallel by a sprate 13. As can be seen from the figure, in series arrangement The cases 15 of the corresponding cells 10 are connected to each other by a conductive member 18 disposed therebetween. communicated with each other. Therefore, voltage equalization reaches the individual cell level within the battery. do.

Figure 3 of this specification is also based on the above-mentioned publication, and as mentioned above, Two arrays of cells 20 arranged in series are arranged between each pair of bus plates 21. Shows complete battery including. The lower bus plate 21 of the array is Exists on a normal aluminum heat sink 22 with a tll'j element 23 sandwiched between them. do.

An electrically insulating layer 24 is provided between the bus plate 21 and the heat sink 22. Figure 3 As shown in Figure 2, the upper bus plate 2] of one array of cells is is connected to the lower bus plate 21 of the array, so that the two arrays are connected in series. It will be connected. This connection connects to a number of rods 25 (only one shown). More given. Rod 25 is aluminum except it has a stainless steel end. It can be formed from For this reason, the end of the rod 25 is placed between the mild steel bus plate. Can be simply welded. To lower the internal resistance of the battery as much as possible Welded connections are preferred. Stainless steel ends easily attach to aluminum rods Although it can be friction welded, aluminum cannot be welded to mild steel.

Another method is to bend a single plate so that the upper bus plate and It can function as a lower bus plate for adjacent arrays. single play The middle portion of the rod extends between the arrays and eventually replaces the rod 25.

It is an object of this invention to provide an improved batch I-no.

According to the invention, a plurality of high temperature cells and at least one conductor made of composite material are provided. including an electrically conductive structural member, the composite material having a copper layer sandwiched between first and second layers of steel. A battery is provided, including a battery.

The inventor believes that the composite material used in this invention has a relatively low resistance due to the copper layer. I understand that it will be lower. Prior art conductive structures requiring low resistance Structural members made of composite materials as defined in this invention have a Due to the relatively low resistance of the composite material, its thickness can be reduced. copper layer Steel layers on both sides provide strength at the cell's operating temperature. With this invention Conductive structural members made of defined composite materials have the same strength and resistance as the prior art It has been found that the weight is reduced by 59% compared to conventional conductive structures. this The reduction in the weight of the conductive structural elements results in considerable weight savings per battery. indicates a vehicle used in a vehicle or carried for other reasons. This is particularly important for secondary batteries that require this.

The use of steel as an outer layer in composite materials makes steel easier to weld than copper. This means that the structural member can be easily welded to other materials. person skilled in the art If so, the weldability of the steel is low (partially determined by the surface of the steel on which the welding takes place). You will be able to understand that In some steels, oxide layers are formed during the manufacturing process. may form due to exposure of the steel to an atmosphere. This oxide layer This oxide layer may reduce the weldability of the steel due to It will need to be removed before welding.

Steel has the advantage that it does not easily oxidize and is furthermore resistant to sulfur attack. is preferred. If the steel does not oxidize easily, it may be necessary to remove the oxide layer before the steel is welded. problems are solved. Furthermore, structural members are more resistant to attack while the battery is operating. There is sex. Especially when the cell gets damaged during operation and sulfur leaks out of it. If this occurs, it indicates resistance. Therefore, steel protects copper from sulfur attack. It becomes.

Advantageously, the steel contains less than 13% by weight of chromium, preferably less than 5%. Ste Steels with a relatively high proportion of chromium, such as stainless steel, are oxidation resistant but also It's quite expensive. The chromium content of the steel is preferably 1.25% by weight.

The copper content of the steel is advantageously greater than 0.1% by weight and ranges from 0.25 to 0.55% is preferred. Adding small amounts of copper to steel helps form a martensitic structure, Gives strength to steel.

Advantageously, the steel contains carbon in the range 0.075% to 0.2% by weight. , preferably about 0.1%. Adding a large amount of carbon gives strength to steel. However, if there is too much carbon, the steel will become hard, but it will break easily and cannot be formed.

The present invention will be specifically described by way of examples only, with reference to the accompanying drawings.

FIG. 1 is a perspective view of a sodium/sulfur cell.

Figure 2 shows a series arrangement of cells placed between a pair of bus plates! batteries containing multiple This is a diagram illustrating the following.

FIG. 3 is a perspective view of a conventional battery including two arrays of cells arranged in series.

Figure 4 shows a series arrangement of sodium/sulfur cells! A schematic of a battery containing multiple arrays of This is what is illustrated.

FIG. 5 schematically shows a composite material according to the present invention.

FIG. 4 shows multiple arrays of sodium/sulfur cells 32 in series (designated 30A and 30B). This is a diagram of a part of the pantry including the two Mechanical structure of the array The configuration is the same as that described with reference to FIG. 2, and will not be described in detail here. cell's The positive terminal of each series arrangement is connected to the first bus plate 34, and the positive terminal of each series arrangement of cells is The negative terminal of the series arrangement is connected to the second bus plate 36 (arrays 30A, 30 In each of B, for clarity, a series arrangement of cells! only one is shown).

As previously mentioned, sodium/sulfur cell batteries have several series configurations of cells. I remember that arrangement. Allows individual cells within a battery to have the same orientation Therefore, arrays 30A, 30B in the battery are connected to the same multiple terminals. The bus plates are oriented so that they are all on the same side of the battery. Illustrated implementation In the example, a series array of cells! The bus plate 34 connected to the positive terminal of At the bottom is a bus plate 36 connected to the negative terminal of the series arrangement of cells.

An inter-array connector 38, actually in the form of a parallelogram, directly connects the arrays 30A, 30B. Connect to columns. In addition to providing electrical connections, interconnectors 38 also provide structural connections. Also provided.

To provide both electrical and structural connections such as bus plates 30A, 30B. The necessary battery components and inter-alignment connectors 38 are shown schematically in FIG. , made of composite material 40. Material 40 was sandwiched between two steel layers 44.46 It has a copper layer and is shaped like a notebook. The steel used in certain examples is Co A formable high-strength low-alloy weldable steel manufactured under the name r-Ten"A". Ru. It has an atmospheric corrosion resistance that is estimated to be more than three times that of mild steel. C.

The approximate composition expressed in weight percent of r-Ten"A" is as follows: Two elements: weight% Carbon maximum 0.12 Silicon 0.25 to 0.75 7ngan 0.20 to 0.25 Phosphorus maximum 0.04 Sulfur maximum o, os.

Chromium 0.30 to 1.25 Nickel maximum 0.65 Copper 0.25 to 0.55 Iron remainder The copper used is electro-smelted grade or general purpose steel.

Composite materials are typically produced by high pressure cold rolling. Materials to be joined must be clean and sent through rollers. Due to the very high pressure, material cleanliness, the material Cold join. Furthermore, rolling allows the overall thickness of the material to be precisely reduced. Ru. The final ratio of material thicknesses is determined by the combination before rolling, as known to those skilled in the art. This can be determined by selecting the approximate initial thickness of the material to be used.

The inventors believe that the composite material described can be used as a conductive structure in sodium/sulfur cell batteries. It has been found that the material has the characteristics necessary to provide a structural member. The copper layer 42 is Has a low resistance to keep the internal resistance of the notebook as low as possible. Cor-T The en″A″ layers 44,46 protect the copper 42 from sulfur attack. as opposed to copper , Cor-Ten "A" is more weldable, so it has easier electrical connections. can be formed into Furthermore, Cor-Ten″A′ (as opposed to copper) It has sufficient strength at the operating temperature of the cell. Cor-Ten “A” itself was attacked by sulfur. sulfur attack reduces the cross-sectional area of the plate and This reduces the risk of increased resistance and physical loss of contact between elements.

A conventional electric element made of a 2 mm thick low carbon plate (mild steel) has a temperature of 0 at 350°C. It had a resistance of 84Ω. In contrast, as mentioned above, using composite materials An electrical element with a resistance of 3 Ω is made, but with a copper layer thickness of 0.2 mm, C.

The thickness of the two layers 44.46 of r-Ten″A″ is 0.3 mm, so the total The body thickness was 0.8 mm. As pointed out in the previous section, conventional low carbon plates and Comparison of the element density and cross-sectional thickness of the composite materials used in the present invention revealed that the use of composite materials It was found that the weight of the element could be reduced by 59%, which is the weight of each battery. will result in considerable savings.

A reduction in the overall cross-sectional thickness of the device is made possible by the low resistance of copper. Moment of inertia of section Reinforcing ribs can be provided along the length of the element to increase the C The strength of the or-Ten"A" material allows devices to be made with this reduced thickness. can. If necessary, reinforcing ribs can be formed by pressing grooves or grooves extending longitudinally and laterally in the structural member. It can take the form of an outline. The depth of the groove depends on the stiffness required and the available space. Exists. Also conductive structural members made of composite materials with a thickness of up to 3 or 4 mm. Also proposed.

The invention is described with reference to a composite material comprising Cor-Ten"A". Co There are many advantages to using r-Ten"A". In particular, it is less expensive than stainless steel. It has low corrosion resistance and has sufficient resistance to sulfur attack. Those skilled in the art will understand the properties of steel. You will be able to understand the individual effects of alloying elements on other types with the required properties Composite materials using steel can also be used.

It will be obvious to those skilled in the art that improvements to the above embodiments may be made within the scope of this invention. Will.

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Continuation of front page (72) Inventor Molyneux, John United Kingdom, Doubleny 7.2AN, Cheshire, Runcorn, Halton ・Village, 49 Main Street

Claims (17)

[Claims] 1. A battery comprising a plurality of high temperature cells and at least one electrically conductive structural member made of a composite material. a battery, wherein the composite material includes a copper layer sandwiched between first and second steel layers; Terry. 2. 2. The battery of claim 1, wherein said steel is not easily oxidized. 3. 3. The battery of claim 2, wherein said steel is resistant to sulfur attack. 4. 4. The steel according to claim 1, wherein the steel contains 13% by weight or less of chromium. battery. 5. 5. The battery of claim 4, wherein said steel contains less than 5% chromium by weight. 6. 6. The battery of claim 5, wherein said steel contains 1.25% chromium by weight. 7. 7. The steel according to claim 1, wherein the steel contains 0.1% by weight or more of copper. battery. 8. 8. The battery of claim 7, wherein said steel contains 0.3% by weight or more copper. 9. 8. The steel comprises copper in the range of 0.25% to 0.55% by weight. is the battery listed in 8. 10. Claim 1: The steel contains carbon in the range of 0.075% to 0.2% by weight. The battery according to any one of 9 to 9. 11. 11. The battery of claim 10, wherein the steel contains about 0.1% carbon. 12. a plurality of cells or cells disposed between the first and second conductive bus plates; including a series arrangement, each of said bus plates including a series of cells to form an array. or claim 1, which functions to interconnect corresponding terminals of a series arrangement of cells. The battery according to any one of item 11. 13. A battery comprising a plurality of arrays as defined in claim 12, wherein adjacent arrays A series connection between columns connects the upper bus plate of the first array to the lower bus plate of the adjacent array. A battery made of at least one sheet of material connected to a spray plate. Lee. 14. The at least one sheet material is arranged on the upper bus plate and the upper machine. 14. The battery of claim 13, extending along each side of said lower plate. . 15. said at least one sheet-like material is substantially parallelogram-shaped; The battery according to claim 13 or 15. 16. 14. The at least one sheet-like material is made of a composite material. The battery according to any one of item 15. 17. A battery substantially as described in any one of Figures 4 or 5 of the accompanying drawings. Lee.