JPS61140058A - Separator for cell - Google Patents

Abstract

PURPOSE:To improve the liquid holding performance of separator thus to improve the self-discharge performance by providing scale projections on the surface of glass fiber constituting a separator. CONSTITUTION:In a separator made of glass fibers having diameter shorter than 10mum, scale projections are provided on the surface of glass fiber. Said projections will serve as a kind of liquid sump to improve hydrophilic performance thus to hold sufficient amount of electrolyte. Consequently, the electrolyte can be utilized effectively thus to improve recovery performance of charging capacity after self-discharge.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a separator for batteries, particularly for sealed lead-acid batteries.

BACKGROUND OF THE INVENTION Sealed lead-acid batteries, which are used as power sources or backup power sources for portable devices, have advantages such as being easy to handle and being inexpensive compared to other secondary batteries. However, it has the disadvantage that self-discharge occurs during storage during the distribution process, and furthermore, capacity recovery after charging is low.

Conventionally, this type of lead-acid battery has used a glass mast-like separator made of glass fibers with a fiber diameter of 10 μm or less.

Problems to be Solved by the Invention However, despite the aqueous properties of glass fibers, such separators have the drawbacks of low electrolyte absorption and large self-discharge during storage. .

The present invention aims to improve the conventional problems, and aims to improve the electrolyte absorption property of the separator, and to provide a sealed lead-acid battery with less self-discharge. In particular, in sealed lead-acid batteries in which the amount of electrolyte is regulated, improving the liquid absorption of the separator has a great effect on improving storage characteristics.

Means for Solving the Problems In order to achieve the above object, the present invention is characterized in that, in a separator made of glass fibers having a fiber diameter of 10 μm or less, scale-like protrusions are provided on the surface of the glass fibers.

By doing so, the scale-like protrusions of the separator act as a kind of liquid reservoir, increasing its hydrophilicity and making it possible to retain a sufficient amount of electrolyte.

In a battery configuration, sufficient electrolyte retention in the separator means that ions can diffuse easily, and even if sulfuric acid in the electrolyte is consumed during self-discharge, sulfuric acid will not be released from the bulk inside the electrode plate. The increase in pH inside the electrode plate can be suppressed. Therefore, a sufficient amount of electrolyte exists at the reaction interface, making it possible to use the electrolyte effectively and improving capacity recovery during charging after self-discharge.

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

FIG. 1 shows a schematic diagram of a glass fiber 1 provided with scale-like protrusions 2. As shown in FIG.

Two positive electrode plates filled with paste made of lead oxide, #sulfuric acid, etc. in a grid made of Pb-Ca alloy, and three negative electrode plates.
A 12V battery with a 10 hour rate of 2 Ah was constructed by combining the two sheets. Conventional Example A uses a glass mat-like separator made of smooth glass fibers with a fiber diameter of 10 μm or less, and Wooden Example B uses a glass mat-like separator with a fiber diameter of 10 μm as shown in Figure 1.
A glass mat-like separator having the following glass fibers 1 and scale-like projections 2 on the surface was used.

Figure 2 shows the remaining capacity due to self-discharge performance after being stored at 50°C for 2 months and the subsequent charge recovery capacity.

Each factor is shown in the third factor. It is clear that product B of the present invention is superior to conventional product A in both cases.

As shown in the above examples, these improvements made it possible to improve self-discharge performance.

Effects of the Invention As described above, in the present invention, by providing scale-like protrusions on the surface of the glass fibers constituting the separator, it is possible to provide a separator with high liquid retention, which is effective in improving self-discharge performance. Furthermore, when the electrolyte is injected into the pond t6, yapa v=p. It also has the advantage of being easy to inject with 9 aqueous electrolytes.

[Brief explanation of drawings]

Fig. 1 is an enlarged schematic diagram of the glass mat-like hexalactate fiber according to the present invention, Fig. 2 is a characteristic diagram showing the residual capacity after storage, and Fig. 3 is a diagram showing the capacity recovery characteristics by charging after storage. be. 1... Glass fiber, 2... Scale-like projections. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] 1. A battery separator made of glass fiber, which is a glass mat-like separator made of glass fibers having a fiber diameter of 10 μm or less, and characterized in that the surface of the glass fibers has scale-like protrusions.