JPS5812995B2 - high temperature battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to high temperature batteries that operate at high temperatures.

A high-temperature battery is comprised of a battery body containing battery reaction parts such as an anode, a cathode active material, and an electrolyte, as well as a heating element that heats it, a heat insulating material, and an outer container, and is generally powered by an external power source. The temperature is raised from room temperature to the operating temperature and then maintained at the operating temperature, and battery characteristics are greatly affected by the quality of the structure of the heat insulation system.

If the battery body is directly covered with a heat insulating material, the problem is relatively minor if the battery body is lightweight, but the packing density of the heat insulating material changes greatly due to its own weight, vibration, impact, etc., and the drawback is that the heat insulation performance is significantly reduced. there were.

Therefore, in conventional high-temperature batteries, such as sodium-sulfur batteries, as shown in the cross-sectional view of main parts in FIG. It is fixed by the body 5.

6 is a connection line (through line) with the outside.

However, this battery also had the drawback of high heat loss.

The present invention eliminates the above-mentioned conventional drawbacks by housing the battery body in an outer container via a heat insulating material, and fixing the battery body to the heat insulating material and the outer container using a battery output wire or a heating wire. The present invention provides a high-temperature battery with low heat loss.

That is, it has been found that the heat loss of conventional sodium-sulfur batteries is due to heat conduction.

In particular, heat loss due to thermal conduction from the support and fixing base of the battery body is large, and as the weight of the battery increases, the support and fixing base also become larger, and the heat loss increases accordingly.

Metal materials used for supports and fixing bases generally have good electrical conductivity as well as thermal conductivity, especially silver (360 K
c a l /mh'C), copper (3 40 K c
al/mh'c), aluminum (180
K cal /rnh (°C), etc. have high thermal conductivity, and the use of metal materials for the support and fixing table results in large heat loss.

In addition, when using non-metallic materials (high load-bearing insulation materials, etc.), high-density materials (for example, refractory bricks 0.5 to 1.25 f/
cm') High thermal conductivity (0.2-0.45Kcal/mh
'C), which is slightly better than metal materials,
Vibration and impact resistance are poor, and other good heat insulating materials (density 0.
06-0. 2g/cm', thermal conductivity 0.06~0
．． 15K cal/mh'c), the weight is increased and the thermal properties are also deteriorated.

For this reason, it is most desirable to uniformly arrange and use good heat insulating materials.

However, in high-temperature batteries, the operating temperature of the battery main body may differ between the reaction section (near the electrolyte), the active material storage section (both electrode active materials), and the terminal section.

For example, in a sodium-sulfur battery, the temperature in the reaction zone is around 300 DEG C., and a temperature of about 100 DEG C. to 200 DEG C. is sufficient to keep the sodium in the active material reservoir (commonly referred to as the sodium reservoir in the case of sodium cathode) in a molten state.

When such temperature differences occur, it is desirable to uniformly arrange and use heat insulating materials having optimal thermal characteristics at each temperature, and the present invention is well suited for this purpose.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A high-temperature battery according to an embodiment of the present invention will be explained with reference to the drawings.

FIG. 2 is a sectional view of the battery, and FIG. 3 is an enlarged sectional view of the main part.

The battery body 1 is inserted into an outer container 3 made of stainless steel or the like with a heat insulating material 2 arranged around it.

The outer container 3 is composed of an outer container 3-1 and an inner container 3-2, and a heat insulating material is inserted between them.

A terminal 8 is attached to a partial connection insertion hole of the outer container 3-1 via an insulating fixing frame 7, and a terminal 10 is attached to a partial insertion hole of the inner container 3-2 via an insulating fixing frame 9. A connecting through wire 11 is provided between both terminals 8 and 10 to completely eliminate the gap around the through wire to prevent heat leakage.

This connection through line is connected to the battery body so as to serve as a battery output line.

The other terminals 12 have substantially the same structure as in FIG. 3, including an insulating fixing frame and connection through wires, and are connected to other polar terminals of the battery body, although not shown.

The terminal can be fixed by screwing, crimping, welding, etc.

Since the battery main body is suspended from the upper part of the exterior by these battery output lines, the load on the lower insulation material is not reduced, and the thickness can be maintained at a constant level.

In this case, the heating wire that heats the battery body does not need to be thin and have no supporting and fixing ability.

Conventionally, these battery output lines were only made to have the shortest length in order to minimize the electrical resistance, but now we have developed a structure that prevents heat dissipation by maintaining strength under the load of the battery and by adding thermal elucidation. It became necessary.

In order to improve the strength and reduce heat loss, the use of braided wire (for example, flat, round, square braid, etc.) has been particularly effective.

The metal conductive material used may be single or composite materials such as copper, nickel, aluminum, stainless steel, iron, zirconia, tungsten, and molybdenum, and the tensile strength is generally 4 to 40 kg/mmt for copper and 7.5 kg/mmt for aluminum. 5-4
0 kg/mmt, stainless steel 50~75kg/mm
It is also possible to combine various materials.

In the above embodiment, the battery main body is suspended and fixed by the battery output line, but it can also be fixed by a heating wire connected to a heater (not shown) that heats the battery main body.

In this case, the connection through wires and the like have exactly the same structure as in FIG. 3.

Although it depends on the type and weight of the battery, it is preferable to fix it with the battery output line when considering the current used.

In the present invention, since the battery main body is supported and fixed by the battery output wire or the heating wire, no other support or fixing stand is required, and heat loss can be reduced accordingly, and materials can be saved. I can do it.

The reason why heat loss was reduced by using braided battery output wires and heating wires is that the surface area of the wires increased, increasing heat dissipation within the insulation material, and reducing the amount of heat that reached the outside. It is.

FIG. 4 shows the relationship between the surface area (m') per meter of braided wire and the amount of heat dissipated (W).

In the figure, the heat dissipation density (W/mF) is 20
0, B is 100, C is 50, and D is 25.

As can be seen from this, the amount of heat dissipation increases as the surface area increases.

Heat dissipation density is affected by the surrounding atmosphere (especially temperature difference) in which the braided wire is placed.

A comparative test with a conventional high-temperature battery, a sodium-sulfur battery, revealed the following results.

The conventional battery has the configuration shown in Figure 1, and the battery of the present invention has the configuration shown in Figure 2.The battery capacity is 5KW class.
The battery weighs approximately 250 kg, and the heat insulating material is asbestos, and the battery output wire of the present invention is stainless steel plain braided wire (0.23 mm φ 240
book) was used.

FIG. 5 shows a comparison of temperature characteristics and supply heat amount characteristic curves.

In terms of temperature rise and temperature maintenance characteristics, the temperature curve of conventional batteries is T2.
(o-b: temperature increase, b-c: temperature maintenance), and the supplied heat amount curve was Q2 (Obl'' temperature increase, b1c1: temperature? maintenance).

On the other hand, the temperature curve of the battery of the present invention is T(o-a: temperature increase;
a-c: temperature maintenance), the amount of heat supplied is Ql (Oal” temperature increase,
ale2' temperature maintenance).

As can be seen from FIG. 5, compared to the conventional battery, the battery of the present invention was able to raise the temperature in a short time, maintained a smaller amount of heat during operation, and was able to reduce the amount of heat supplied by 30%.

In addition, the stainless steel plain braided wire (0.23 mm diameter, 240 wires) had sufficient durability against the weight of the battery, and could be supported and fixed, and could be energized (charged and discharged).

This is because the battery main body is fixed with the battery output wire, and the periphery of the battery main body can be completely covered with a heat insulating material without providing a support or a fixing base.

As described above, the present invention provides a high-temperature battery with little heat loss, and has great industrial value.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main parts of a conventional high-temperature battery, Figure 2 is a sectional view of the main parts of the battery of the present invention, Figure 3 is an enlarged sectional view of the main parts, and Figure 4 shows the surface area of the braided wire and the amount of heat dissipated. The relationship diagram, FIG. 5, is a comparison diagram of temperature characteristics and supply heat amount characteristic curves. 1...Battery body, 2...Insulation material, 3.
...Outer container, 4...Fixing stand, 5...
...Support, 6...Connection line, 7,9...
・Fixed frame, 8, 10, 12...Terminal, 11・
... Connection through line, T1 ... Temperature characteristic curve of the battery of the present invention, T2 ... Temperature characteristic curve of the conventional battery.

Claims (1)

[Claims] 1. A high-temperature battery characterized in that the battery body is housed in an outer container via a heat insulating material and the battery body is fixed to the outer container using a battery output wire made of metal braid or a heating wire made of metal braid. .