JPS59221973A - High temperature type battery - Google Patents

Abstract

PURPOSE:To obtain a separator for a fused salt battery with porosity, and good wetting into fused salt and with few changes in thickness, by using inorganic material such as molded body of mangesium compound or boron nitride that is stable against lithium, as the raw material. CONSTITUTION:A battery set up by interposing a separator 2 with 85% porosity of a particle layer formed by injecting a porous magnesia particle between frame bodies made of boron nitride, between a positive electrode 1 that uses iron sulfide as the active material and a negative electrode 3 that used lithium-alumium alloy as the active material, showed a high value of 83% for the coefficient of utilization of the positive electrode active material at the 2.5A charge and discharge. In addition, the thickness of a separator layer after 100 cycles was not changed at the 8-hour rate charge and discharge and the shape change of the plate was also relaxed.

Description

[Detailed description of the invention] Wood invention (1, using lithium or lithium alloy for f:11!i, using iron sulfide, -r!i!i iron oxide, etc. for the IR electrode, and using lithium such as boron nitride for the separator) This method uses porous magnesia particles filled in a frame with an inorganic material that is stable against t')/i to form a molten tantalum salt battery.

For AC, high-temperature batteries using molten salt, d5 is
Lever 1 note + 4 quality, 5 o which is battery operation depletion
Stability around o'C11. Corrosion resistance in molten salt, live material v
Boron nitride and magnesia have been detected from the surface of the reaction 1'l''Q. This felt separator has a porosity of just under 90%, exhibits a large iJ<'c (1Ti), and satisfies the characteristics required for battery separators, such as electrical insulation. , ] 2 The cost of making felt to make the palator porous was extremely high, and there were problems in that the retention of the active material was insufficient. Since it does not get wet, after making boron nitride into a felt, magnesia is precipitated on the surface of the fiber using magnesium nitrate, which produces magnesia by thermal decomposition, to improve wettability to molten salt. It required a processing step.

In general, separators using boron nitride felt become thicker as the electrode plates deform due to charging and discharging.
However, there were drawbacks such as shortening the life of the battery.

Since magnesia has not been made into fibers to date, attempts have been made to use magnesia powder in separators. But using powder! Pareku has a small porosity of around 50%, and its material utilization rate in batteries remains low. :, even in powder! Gome III! After 11 steps, I press-molded it with electrolytic M powder and made it into a temporary IR.

The present invention (1, 1') improves the deficiencies of these, is inexpensive and easy to handle/'f I-, has good wettability to molten salt, has sufficient porosity, The present invention provides a battery using a separator that always has a uniform (T) thickness.

The following is an example (2 editions) 1 (Jru).

The porous magnesia particles are made of Φ711 magnesia with an average particle size of 0.3 ft, and magnesium as the raw material. T! To Cnesia, add 21 μ% of a solution of 2 gnesium and 21% in terms of magnesia, make it into granules by extrusion granulation method, and then calcinate the granules for 10 (+ +1'C). , particles having pores Y1 and a strong electric current sufficiently able to withstand one branch were prepared.

Next, this porous Y1y81 100・~1! i 0
Using a comb-shaped frame of boron nitride with a grain size of fl and an open top, an iron sulfide cell according to the present invention was constructed as shown in FIG. , charging and discharging tests were carried out.The silk mats of the battery were press-formed, respectively, between the positive and negative electrode plates, as shown in Figure 2. After inserting the comb-shaped frame into the battery case, insert a porous plate between the teeth of the comb-shaped frame. ;IL performed by filling magnesia particles 6
In the figure, (1) is a positive electrode using iron sulfide as an active material, with a particle size of 50f1 to 300μ.
Electrolyte salt 11 dilithium-potassium chloride with a particle size of 50Iz to 150fl was added at 7% ISl',
After filling the honeycomb-shaped current collector, at room temperature 100
Calculated at MPa, J is applied when forming 1 and making it into a plate shape.i
'T 13, a 200 mesh stainless steel mesh was placed on the surface of the electrode plate to hold the active material. , (2) is a separate lake formed by filling porous magnesia particles into a comb-shaped boron nitride frame (4) with an open top according to the present invention, and (3) is a lithium-aluminum frame. This is a negative electrode that uses 2911 alloy as the active material.

Like the positive electrode, the negative electrode also has a honeycomb-shaped current collector with 50
Regram-aluminum alloy powder with grain size 1α from μ to 300I and electrolytic 7go powder 1j) grain size from 5011 to 100μ) '% 'i filling, chamber'1
fjn NiT 100M Pil It is a plate-shaped body which has been molded using ffjn. Also in the negative electrode, the active material 1 + AJ, ++ l
,: 200 mesh stainless steel mesh I11
For the solute, 411 δA (a solution of 54% by weight of lithium chloride and potassium chloride 11, 411 δA) was used. The capacity was 25Ah and 100△11, and the capacity of the f1 electrode was 1, 3, and 11'4 for the positive electrode.

According to the present invention, porous magnesia particles are formed by pouring porous magnesia particles between the frames of boron nitride;
11 degrees IJ: It shows a large value of 85%, and according to the mercury IE large method (measured), the pore size at 2 is 30μ and 111
showed a small peak. The former pores are the gaps between particles (
This is because the minute 4T pores described later are distributed inside the particles (5), but the gaps between the particles are smaller than the particle size of the active material, and a layer of 1 layer is sufficient. Living things +, +4
You can see that j is Ho1ji and Kiruko J2 is.

In a battery test using a battery with a capacity of -frf of 25Δh, the battery using the porous magnesia particles according to the present invention showed a high positive electrode active material utilization rate of 83% during charging and discharging of 2.5Δ. In a similar battery using a magnesia powder separator with 14 composition and 46% porosity, the active material utilization rate was 6.
The porosity of boron nitride with a porosity of 89% was 86%, which is the same value as the porosity of the present invention.

A 100A h battery with a plate area '+(r) was roughened, and the effect of deformation of the plate on charge/discharge of the battery was examined.Battery using boron nitride felt l! 8 hour rate of charge/discharge r 100 (J-The electrode plate thickness after cycling is 1.29'i for the positive electrode, and the battery bulge for the negative electrode is biased towards the center of the electrode plate, and the thickness at the highest part is l, J: The thickness of the separator was reduced to less than 1.5 times the initial thickness in the medium heat section of the battery. In the battery used in
<The shape change of the electrode plate is also alleviated, and the nitrided bow is formed.
T? Batteries J and lQ using pallets are also arranged (()i life is revealed (:!1.Also, the active material utilization rate of the 100△I) battery according to the present invention is the same as that of the 25△11 battery) i1i
As is clear from the explanation of li Irzl', Gino, = 1° or less) and the Cf example, the present invention improves the heat of the I parator with i:r>I<, and reduces the cost by reducing the l, the compound and the commercially available boron nitride molded snow body horn;
Q: , lltI machine is the raw material, ρ hole 〒1 (゛, melt 1'i'l! , 1 nu wet f1 is also good, it's enough (this story 1 course? ++ is held for 1 time, and the change of p] is made using the I-i-i-i-i-i-1-reparator-, which is used to promote the 11 (Jrub).

[Brief explanation of the drawing]

11) Part 1, showing an embodiment of a battery according to the invention
lli side view, 2nd figure Let 1lffi become the present invention)
u! Fig. 1 is a diagram showing a frame of a small nitrided tube, which is a separator structure of H product. . 1... Positive 447.2... Boron nitride frame with porous material) / 11"! 4 - Filling and irritating lever leak, 3...77th

Claims (1)

[Claims] () Lithium l in a boron nitride tube using lithium or lithium alloy for the electrode, metal sulfide for the positive electrode, and filled with magnesia particles of 7 Lt' as a separator between the electrodes;
2. il l) Stable! (r) A high-temperature battery that requires a frame made of a plate to be interposed.