JPS6132783B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method of charging a secondary battery such as a lead-acid battery, and in particular, uses intermittent pulse current during charging to prevent electrolyte scattering and loss and to reduce loss of charging energy within the battery. It also reduces When a pair of electrodes is immersed in an electrolytic solution and a direct current is applied to electrolyze it, the anions in the solution are attracted to the anode and the cations are attracted to the cathode. It becomes larger near the cathode, and the ion concentration becomes non-uniform, resulting in a kind of concentration cell, producing an electromotive force in the opposite direction to the externally applied DC voltage. This phenomenon is called polarization effect (polarization effect), and since this effect increases battery loss [charge capacity (IH) - discharge capacity (IH)], the above-mentioned Many efforts have been made to eliminate the polarization effect, including methods such as stirring the solution and using disinfectants, but no satisfactory results have been achieved. Recently, when charging a battery, it has been proposed to superimpose high frequency power of 1 to 100 KHz on DC power obtained by full-wave rectification of the commercial frequency, as described in Japanese Patent Publication No. 46-4936, for example. There is. In this case, the non-uniformity of the ion concentration due to the movement of cations and anions in the electrolyte is dispersed and made uniform by high-frequency power, which reduces the polarization effect and is consumed to form a local battery. It was understood that the loss energy was reduced. However, because the high frequency component tends to be superimposed on the DC power, and rather increases with the DC power, a voltage is constantly applied between the electrodes, and uneven concentration dispersion due to the high frequency is not possible. However, the polarization effect due to the DC component still exists. In the above case, high-frequency power also has the ability to store energy for chemical changes, but the high-frequency power when superimposed on the DC voltage is small, and does not contribute to, for example, storing a large amount of energy and increasing discharge capacity. do not have. The present invention takes these points into account and devises a method of charging using pulsed current intermittently, and by setting specific pulsed current conditions, the dispersion of the electrolyte is prevented. The conditions for the pulse current are that the pulse width (special time of the pulse current) is at most 200 μs, preferably 50 μs or less, and the rest period between the pulse currents is at least twice the pulse width. By increasing the voltage by about 30 times from 1 to 30, the pulse current is stopped before the polarization effect occurs by stopping the application of the pulse current, and by applying a new pulse current, charging is not performed by energization in a state where the ion concentration is uneven. , which reduces energy loss within the battery, reduces heat loss, and reduces evaporation of the liquid, which can increase the storage of chemical energy, that is, the energy storage density. Furthermore, chemical energy can be stored not only in the surface layer of the electrode but also deep inside the electrode. The maximum pulse width of the pulse current is 200
μs, preferably 50 μs or less, usually 5 to 30 μs
The rest time of the pulse current is at least 9 times to 30 times the width of the pulse, and
Normally, 3 to 4 times to about 10 times is better. If it is more than 30 times, it is not preferable from the point of view of charging time efficiency, etc., and if the rest time is short, less than twice, the interval between pulse currents becomes too short. This promotes the polarization effect, and ultimately the polarization effect can be reduced by appropriately providing intervals between pulse currents. The present invention relates to automobile engines, fixed batteries, chargers,
It can be used for any quick charger etc. Note that the amplitude of the pulse current is determined by the above-mentioned pause time of 3
If it is more than twice that, several 10A can be applied without special precautions.
The above is what you get, but it depends on the response speed of the switch such as the transistor that forms the pulse current, the required number according to the current amplitude, the voltage of the charging power source (the voltage of the pulse current), the charging resistance between the electrode terminals of the battery, etc. However, it should be set so that the required average charging current can be obtained. To explain the present invention using an example, the size is 160 mm.
In a lead-acid battery consisting of lead electrodes of ×100 mm ×5 mm and approximately 450 c.c. of sulfuric acid solution with a specific gravity of approximately 1.23, a pulse width of 20 μ
Average gas when charging for 15 hours with a constant room temperature of 20℃ using a pulse current with a pause width of 60μs and a current amplitude of 3A (average approx. 1A), and when charging with direct current with an average current of 1A. Generation amount (cc/mi
n) and the amount of liquid loss (%) were measured and found to be as follows. The liquid temperature is approximately 28℃ for the former and approximately 40℃ for the latter.
It was ℃.

[Table] That is, according to the present invention, although the amount of gas generated is large, the amount of scattering loss due to liquid evaporation and other causes is small, the energy loss due to polarization and other causes during charging is small, and the liquid It was particularly excellent in terms of low wear and tear.

Claims (1)

[Claims] 1. When charging a battery, the pulse width of the pulse current is set to 200 μs or less, and the rest time between pulse currents is set to 2 to 30 times the pulse width of the pulse current. By charging with intermittent pulse current. ,
A battery charging method characterized by reducing heat loss and liquid evaporation.