JPS6043627B2 - Manufacturing method for cathode plates for lead-acid batteries - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a cathode plate for a lead-acid battery that improves high rate discharge performance at low temperatures and room temperatures.

Conventionally, lead-acid batteries installed in automobiles for starting engines often become unable to start the engine in the winter season or in cold regions due to low temperatures. This is because the low-temperature, high-rate discharge performance of lead-acid batteries deteriorates, and the main cause is thought to be the cathode plate. In other words, the cathode plates of conventional lead-acid batteries are manufactured by adding ordinary additives such as barium sulfate, lignin, and carbon to lead powder to create a paste, and then filling the electrode grid with this paste. Of the additives, barium sulfate and carbon are said to improve life performance, and lignin is said to improve high rate discharge performance and life performance.Additive specifications include barium sulfate 0.3 to 2.0% and lignin 0.3% to 2.0%. It is thought that this is because the amount of lignin, which affects high rate discharge performance, is small, as the amount of lignin that affects high rate discharge performance is used in the range of 1 to 0.7% and 0.1 to 5.0% of carbon.

However, if the amount of lignin added is simply increased beyond the conventional amount, the active material will expand and become more likely to peel off, which will actually shorten the life of the lead-acid battery. The present invention solves the above-mentioned problem, and the surface of the cathode plate obtained by filling the electrode plate grid with a paste containing ordinary additives containing 0.1 to 0.7% lignin. By dipping or showering in an aqueous lignin solution, the amount of lignin impregnated is 0.8 to 5.
There is a method for producing a cathode plate for a lead-acid battery, which is characterized by impregnating the cathode plate so that the content of the lead-acid battery is 0%. An embodiment of the present invention will be described.

Lead powder, barium sulfate 0.3-2.0%, lignin 0.1
~0.7% and carbon 0.1-0.5% of the usual additives were added and kneaded to create a paste, and the electrode plate grid was filled with this paste, and the resulting cathode plate was soaked in acid. Thereafter, the cathode plate is showered with an aqueous solution of lignin to impregnate the surface of the cathode plate, and then dried and aged to produce a cathode plate for a lead-acid battery.

Therefore, the cathode plate obtained as described above contains a large amount of lignin on its surface, and the inside has a normal lignin content, so that ligonin expands only on the surface of the active material in a lead-acid battery. This increases the contact area for electrochemical reactions and improves high-rate discharge performance, but since the inside of the active material expands only to the same extent as before, the active material does not peel off from the electrode lattice, making it a lead-acid battery. 1- There is no way to shorten the life of the product.

However, the lignin impregnated on the surface of the cathode plate is 0.8
If it is less than 5.0%, the amount of lignin impregnated inside the plate will be approximately the same as that of the internal lignin, and therefore a high rate discharge performance comparable to that of conventional cathode plates can be obtained. This causes the active material inside the plate to expand excessively, making it easy for the active material to fall off.

The amount of lignin impregnated is determined by adjusting the concentration of the lignin aqueous solution, the soaking or showering time, and the like. In the production of the above cathode plate, the use of immersion in an aqueous solution of lignin or showering to change the amount of lignin added between the inside and the surface of the cathode plate facilitates the production of the cathode plate. High efficiency at room temperature (25°C) and low temperature (-15°C) for N5OZ type lead-acid battery using the cathode plate obtained by the present invention (invention product A) and a conventional lead-acid battery of the same type (conventional product B) The relationship between discharge performance and charge/discharge cycle is shown in FIGS. 1 and 2, respectively.

This is an SAE in which one charge/discharge cycle is charging at 14.8V for 10 minutes and discharging at 25A for 2 minutes.
During life test based on standard, initial, 2000th cycle, 4
At the 000th cycle and the 6000th cycle, 30
These are the results of measuring the duration of 0A high rate discharge. From the above results, it was found that the product A of the present invention has a higher high rate discharge performance than the conventional product B, and also shows little change over time and maintains a high level.

As mentioned above, the present invention is extremely valuable in that it is possible to manufacture a cathode plate that improves high-rate discharge performance at low and room temperatures without shortening the life of lead-acid batteries, and that the manufacture is simple. be.

[Brief explanation of drawings]

Figure 1 is a curve diagram showing the relationship between high rate discharge performance and charge/discharge cycle at room temperature (25°C) of a lead-acid battery using the cathode plate obtained by the present invention and a conventional lead-acid battery, and Figure 2 is the same. It is a curve diagram showing the relationship between high rate discharge performance and charge/discharge cycle at low temperature (-15°C). A is a product of the present invention, B is a conventional product.

Claims (1)

[Claims] 1 The surface of the cathode plate obtained by filling the electrode plate grid with a paste containing ordinary additives containing 0.1 to 0.7% lignin is soaked or showered with an aqueous solution of lignin, A method for producing a cathode plate for a lead-acid battery, which comprises impregnating the cathode plate with lignin in an amount of 0.8 to 5.0%.