JPS6229059A - Separator for maintenance free lead storage battery - Google Patents

Abstract

PURPOSE:To elongate the life time of a maintenance free lead storage battery significantly by constructing a separator by weaving the mixture of glass fibers of different means diameter or glass fibers of different mean diameter and synthetic fiber. CONSTITUTION:The separator is constructed by weaving the mixture of 3-8wt% of glass fiber of 0.5-2mum in mean diameter and 97-92wt% of glass fiber of 3-9mum in means diameter or 3-8wt% of glass fiber of 0.5-2mum in mean diameter and 96-82wt% of glass fiber of 3-9mum in means diameter and 1-10wt% of synthetic fiber or synthetic pulp. Thereby the decrease of the thickness of the separator at the impregnation of the electrolyte can be eliminated, the absorption velocity of the liquid can be improved very much associated with the improvement of the diffusibility, and the high rate discharge characteristics or recoverability by charging can be improved significantly.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a separator for non-maintainable lead-acid batteries.

(Prior art) Conventional separators for non-maintainable lead-acid batteries are made of glass fibers with an average fiber diameter of 5 to 2 μm, or glass fibers with an average fiber diameter of 3 to 50 μm mixed therein with a small amount of glass fiber or synthetic bulb. is commonly used.

(Problems to be Solved by the Invention) The conventional separator described above is a separator that is interposed between negative and anode plates, assembled into a group of electrode plates, a desired number of which is immovably stored in an IT tank, and impregnated with electrolyte. When using a maintenance type lead acid battery,
The thickness of the separator decreases due to impregnation with electrolyte, and the thickness also decreases as the amount of impregnated electrolyte decreases during use of the storage battery, resulting in poor adhesion to the electrode plates and shortening battery life. The force shortens life. Also, since the electrolyte in the parator is slow to diffuse,
The distribution of the electrolyte in the vertical direction of the separator becomes uneven, and there is less electrolyte in the upper part, and the high rate discharge characteristics and charge recovery properties of the storage battery are particularly poor. Therefore, while maintaining the liquid absorption properties required for the storage battery, it is possible to impregnate the electrolyte and maintain good adhesion with the electrode plate due to the decrease in the thickness during use, while also preventing the diffusion of the electrolyte. An excellent separator with good properties and improved high rate discharge characteristics and charge recovery properties of storage batteries is desired.

(Means for Solving the Problems) The present invention provides a separator for non-maintainable lead-acid batteries that eliminates the above conventional drawbacks and satisfies the above requirements.
3-8% by weight of glass fibers with an average fiber diameter of 15-2 μm and 1% by weight of 97-92 glass fibers with an average fiber diameter of 3-9 μm or 3-8% by weight of glass fibers with an average fiber diameter of 15-2 μm
Weight % and average sacrificial fiber diameter 3-9 μm glass fiber 96-82
% by weight and 1 to 10% by weight of synthetic fiber or synthetic valve.

(Function) With the above structure), even when used in a storage battery and impregnated with electrolyte, there is no decrease in thickness, and as will be shown below, the liquid absorption rate is significantly improved and the diffusivity is improved. This results in significant improvements in high rate discharge characteristics and charge recovery properties.

(Example) Next, the present invention will be explained in detail.

Glass fibers with an average fiber diameter of 1 μm, glass fibers with an average fiber diameter of 4 μm, and synthetic fibers or synthetic pulps of 1 to 3 deniers for improving paper-making properties and bending strength, such as fibrillated acrylic am. were mixed at the respective compounding ratios shown in Table 1 below and made into paper using the normal wet papermaking method to obtain paper separator samples with a thickness of 2+W, that is, conventional product sample shop 1, comparative sample A2, and the present invention product. Specimen genera 3, &4
, A5 and a comparative sample A61C were prepared.

Table 1 shows the results of testing various properties such as liquid absorption rate for each of these.

In Table 1 above, "No load" for liquid absorption amount (1) means that the seven pallets are suspended as they are, and the lower part is immersed in the liquid (1,3 (LH!5OF
), and the "load of 2 degrees" means that the separator is sandwiched between transparent resin plates so that a load of 20 degrees per 1 oocrl is applied, and the lower part is immersed in the liquid (1.5 aa = so?).
). Liquid absorption amount (4) 84% or less under "no load" and 80% or less under "20 load" are unsuitable as retainers.

In the above table, sample &1 either passes the liquid absorption amount or has an extremely slow liquid absorption rate. Sample &2 has a faster liquid absorption rate than Rin 1, but the amount of liquid absorbed is insufficient. Sample black 6 has an extremely good liquid absorption rate, but the amount of liquid absorbed is insufficient. Sample A7 has an extremely insufficient amount of liquid absorbed. On the other hand, Sample 9 & 3.4, s had an appropriate amount of liquid absorption as a retainer, and the liquid absorption rate was extremely fast, and it was observed that the liquid absorption rate was significantly improved compared to Sample &1, which is a conventional product.

In addition, the glass # with an average line m diameter of 4μ used in sample 71L3.4.5! I! It was found that when paper was made by blending 87%, 190%, and 92% of 4ntr Kamekoze bulk fibers, the papermaking properties were poor and it was difficult to obtain a uniform structure. Ta.

Next, the separators of Samples 1 to A7 in Table 1 above were used and incorporated into specific batteries shown in Table 2 below, and the battery characteristics of each test battery were tested using the test method described below.

Table 2 Test method: (a) Initial capacity test (10 hour rate capacity test, 1 hour rate capacity test) [1L1C
If α10 is the current (10 hour rate) or l1lL6a current (1 hour rate), 1. a OV/sen, 0.
In the case of 60V, discharge is performed up to 1.60V/7V, the duration is measured, and the Ah capacity is determined. Ambient temperature during discharge 25±
The temperature shall be 5°C. [11'O is 1/f Ot- of the 10 hour rate rated capacity value (σ).

(b) Self-discharge test After charging and discharging several times and fully charging the battery with a stable capacity, discharge at a rate of 10 hours to 0□. After fully charged, 25
Leave for 84 days at an ambient temperature of ±5°C. After being left alone, the battery was discharged at a rate of 02 for 10 hours without supplementary charging. Further, the battery was fully charged, and after the charging was completed, the battery was discharged at a rate of 10 hours to become Ol. Calculate the self-discharge amount per day by substituting the test results accordingly.

Daily self-discharge t(S)=”””””xlao(
4) 84 (01+ a,) (c) Constant voltage charging life test (1) First discharge a fully charged storage battery (L6G and check full capacity (H)) After discharging in (1), [120 or less current] and continuously charge at a voltage of λ25 to 2.30V/cell.

(During the ID test, discharge at Q and 6Q approximately every 4 months and check the capacity!lk.

(IV) When it is confirmed that the capacity of oii) has decreased to 80% or less of the 1-hour rate capacity and does not rise again, the life span has expired.

M The ambient temperature for this test is 40-45'C.

b) Measurement of internal resistance of storage battery (1) Measure the internal resistance immediately before the capacity confirmation test of the constant voltage charging life test.

(11) A Kelvin bridge was used to measure the internal resistance.

The above test results are shown in Table 3 below and Figures 1@1 and 2.

As is clear from Table 3 and Figures 1 and 2 above,
It can be seen that the batteries using the sample &5, A4 and A5 separators of the examples of the present invention exhibit superior battery characteristics as compared to the batteries using the other sample separators. It can be seen that the superiority of the amount of liquid absorbed and the rate of liquid absorption shown in Table 2 corresponds to the superiority of the battery characteristics shown in Table 3. In other words, in non-maintenance storage batteries, self-discharge decreases as the adhesion between the separator holding the electrolyte and the electrode plate improves; υ is also smaller than that of conventional sample A1, indicating that it is not affected by the decrease in liquid.

Next, looking at the results of a life test using constant voltage charging, we found that samples A3, &A, and A5 of the present invention exhibited significantly changes in internal resistance over time compared to conventional products and other samples 41, A6, and A7. It can be seen that it is smaller and its lifespan has been significantly extended. This means that the separator of the present invention having the configuration shown in Table 2 has less decrease in thickness due to electrolysis and evaporation of water in the electrolytic solution due to charging, and the adhesion of the separator is maintained over a long period of time. means.

Figure 1 shows the 1-hour rate discharge characteristic curves of each battery when using Sample A1, Grave 4, and Black 7 separator as a typical comparative example.
[lL] A separator mainly composed of glass fibers with an average fiber diameter of 5 to 1.0 μm has a low discharge pressure and the shortest duration due to the slow diffusion rate of the electrolyte. One side sample A7
As typified by, a separator mainly made of glass fiber with an average fiber diameter of 50 to 7P has a faster liquid absorption rate than Sample &1, so either the discharge pressure is improved or the liquid absorption rate is significantly inferior. In terms of duration, it actually produces a shorter result than Sample Shop 1.

Figure 2 shows the constant voltage charging characteristics of each battery when samples AI, A4, and A7 separator f are used. Therefore, it can be seen that charge recovery is also the quickest.

The excellent charge/discharge characteristics and battery life of the present invention as described above are
As a result of many tests and studies, we found that 3-8% by weight of glass fibers with an average fiber diameter of 15-2-2% and the remainder with a total average fiber diameter of 3-? - composed of glass fibers or 1 to 1 part of the latter glass fibers
It can be maintained as long as it is constructed by replacing it with synthetic fibers or synthetic pulp of zero weight capacity. It was confirmed that the third component, synthetic fiber or synthetic pulp, simultaneously improved paper formability, bending strength, etc.

(Effects of the Invention) The present invention provides the conventional average fiber diameter of 3 to 9 by configuring the through-shin sehalator as set forth in the above claims.
Compared to a separator made of μ-island glass fiber alone or made mainly of glass fiber, the life of an unmaintained lead-acid battery can be significantly extended, and the charge/discharge characteristics can also be significantly improved.

[Brief explanation of drawings]

Figure 1 is a comparison diagram of discharge characteristics, and Figure 2 is a comparison diagram of charging characteristics. Diarrhea hidden g g g S figure

Claims (1)

[Claims] 1. Mix 3-8% by weight of glass fibers with an average fiber diameter of 0.5-2 μm and 97-92% by weight of glass fibers with an average fiber diameter of 3-9 μm, or 3-8% by weight of glass fibers with an average fiber diameter of 0.5-2 μm. Glass fiber 9 with 8% by weight and an average fiber diameter of 3 to 9 μm
A separator for a non-maintainable lead-acid battery made of a mixture of 6 to 82% by weight and 1 to 10% by weight of synthetic fiber or synthetic valve.