JP3209039B2 - How to charge lead storage batteries - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for charging a lead storage battery, and more particularly to a method for charging a lead storage battery for an electric vehicle.

[0002]

2. Description of the Related Art As a method of charging a lead storage battery, particularly a method of charging a lead storage battery for an electric vehicle, a quasi-constant voltage charging method has been mainly used. This quasi-constant voltage charging method is a charging method in which the applied voltage is changed according to the state of charge of the battery.
FIG. 3 shows the charging characteristic curve. When the battery voltage V is low, a large charging current I flows, and as the battery voltage V increases, the charging current I decreases. Thereby, necessary charging is performed without abnormally increasing the battery temperature. In this charging method, a timer is also used, and when the battery voltage V suddenly increases (about 2.4 V / cell), the timer is operated to control the amount of charge.

[0003]

According to the charging method described above, for example, when charging a lead storage battery at 80% discharge, it takes about 10 to 12 hours to charge. In addition, as the charging time becomes longer, the amount of gas generated from the electrolytic solution increases, and the amount of liquid reduction also increases. Therefore, there was a problem that the interval of water refilling to the electrolytic solution became short.

It is an object of the present invention to provide a method for charging a lead storage battery, which can shorten the charging time and extend the interval of rehydration.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a method for charging a lead storage battery which requires replenishment of an electrolytic solution. And a first charging pattern in which constant current charging of a first charge amount is performed at the end of the constant voltage charging, and a constant voltage charging is performed after the constant current charging, and the first charging is performed at the end of the constant voltage charging. Charging is performed by selectively using a second charging pattern that performs constant-current charging of a second charging amount that is larger than the amount and that can generate gas at the end of charging. Then, the first charging pattern and the second charging pattern are selected such that the number of times of charging using the first charging pattern within a predetermined period is equal to or greater than the number of times of charging using the second charging pattern. I do.

[0006] Here, the "predetermined fixed period" refers to a period of a certain period such as ten days or one month. Note that this period is appropriately determined according to the capacity of the lead storage battery and the state of the load of the lead storage battery, and the same fixed period is not used for all lead storage batteries.

[0007] In the present invention, the total charge amount at one time when the first charge pattern is used is defined as one of the total discharge amount of the lead storage battery.
When the second charge pattern is used, the total charge amount at one time is 111% to 111% of the total discharge amount of the lead storage battery.
When it is set to 120%, good charging is performed.

[0008] In addition, when the lead-acid battery for an electric vehicle is charged using the present invention, the number of days for charging using the first charging pattern within a predetermined period is determined using the second charging pattern. So that the number of days for charging
And the second charging pattern are selected.

According to another aspect of the present invention, a lead-acid battery requiring replenishment of an electrolytic solution is charged at a constant voltage after a constant current charge, and is again charged at a constant current after the constant voltage charge. In a method of charging a lead storage battery that is charged using a charging pattern, when charging is performed n times within a predetermined period of time, the charge amount of the last constant current charging is increased so that gas is generated at the end of charging. Charging will be performed less than n / 2 times.

[0010]

In the method of charging a lead storage battery according to the present invention, a first charging pattern is selected in which constant voltage charging is performed after constant current charging, and constant current charging of a first charge amount is performed at the end of the constant voltage charging. When charging the battery, the charging time is shortened, the generation of gas is suppressed, and the interval between rehydration is extended. Then, a constant voltage charge is performed after the constant current charge, and a second charge that is larger than the first charge amount at the end of the constant voltage charge and can generate gas at the end of the charge.
When performing the charging by selecting the second charging pattern for performing the constant current charging of the charging amount, the shortage of charging that is likely to occur when only the charging based on the first charging pattern is repeated is eliminated.
By stirring the electrolytic solution with the gas generated in the battery case, stratification of the electrolytic solution which causes a difference in specific gravity or sulfuric acid concentration is prevented. In the charging method of the present invention, the number of times of charging using the first charging pattern that does not generate gas within a certain period is set to be greater than the number of times that charging is performed using the second charging pattern that generates gas. By
The present invention solves the problem of insufficient charge of a lead storage battery, suppresses the decrease in electrolyte and the stratification of the electrolyte, and improves the operation and maintenance of the lead storage battery.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the charging method of the present invention will be described. The storage battery to be charged is a lead storage battery for an electric vehicle that requires replenishment of an electrolytic solution, and has a rated voltage of 2 V / cell. After using such a storage battery, first 0.2-0.3C
A constant current charging is performed with the charging current of A, and the voltage of the storage battery becomes 2.
Continue until 5-2.6 V / cell is reached. When the battery voltage reaches 2.5 to 2.6 V / cell, the mode is switched to constant voltage charging, and constant voltage charging is performed up to 90 to 100% of the storage battery.
In the present invention, after the constant-voltage charging, the constant-current charging is further performed. In performing the constant-current charging, the charging amount is changed in consideration of the charging history of the storage battery and the number of times of charging.
Select one of the two charging patterns to charge.

For example, when the first charge pattern is used, 1 to 10% of the discharge amount of the storage battery is charged at a constant current of 0.05 to 0.15 CA, and the total charge amount of one charge is reduced. The required minimum charge amount is 101 to 110% of the previous total discharge amount of the storage battery. When the second charge pattern is used, the discharge amount of the storage battery in the last constant current charge area? Of 1
The battery is charged at 0 to 20%, and the total charge amount is set to 111 to 120% of the total discharge amount of the storage battery. The gas is positively generated, and the specific gravity of the liquid is increased by stirring the electrolyte with the gas.

In selecting the first and second charging patterns, the number of times and the number of days of charging using the first charging pattern within a predetermined period of time depend on the charging using the second charging pattern. More than the number of times and days,
The first or second charging pattern is selected. Or,
When it is considered that charging is performed n times within a predetermined period, charging performed by increasing the charge amount of the last constant current charging so that gas is generated at the end of charging is less than n / 2 times. Try to do it a number of times.

FIG. 1 and FIG. 2 show a charging characteristic curve used in the charging method of the present invention. FIG. 1 shows a charging characteristic curve when the first charging pattern is used. FIG. 7 is a charging characteristic curve when the charging pattern of FIG. As shown in the drawing, the first and second charging patterns differ in the charging time and the charging amount of the last constant current charging. When the charging according to the first charging pattern in FIG. 1 is performed, the charging time and the charging amount of the last constant current charging are short, so that the charging time is shortened, and the generation of gas is suppressed, so that the interval of water replacement is extended. However, if charging is repeated only with the first charging pattern,
It is easy to run out of charge. Therefore, in the present invention, charging is also performed according to the second charging pattern shown in FIG. In the second charging pattern, the charging time and the charging amount of the last constant current charging are longer than those in the first charging pattern. Therefore, if charging is repeated only with the second charging pattern, an overcharged state occurs, and gas is generated every time charging is performed, and the electrolyte decreases. However, the use of the second charge pattern has the advantage of compensating for insufficient charging, and furthermore, the electrolytic solution is agitated by the generated gas, thereby eliminating the concentration difference in the electrolytic solution. Therefore, by appropriately combining the first charging pattern and the second charging pattern, insufficient charging can be solved, and stratification of the electrolytic solution that causes a difference in specific gravity or sulfuric acid concentration in the battery case can be prevented.

[0015] As described above, the constant current charging with different charging patterns is performed selectively after the constant current / constant voltage charging, so that the charging time can be shortened and the interval of rehydration of the electrolyte can be extended. In addition, insufficient charging and stratification of the electrolytic solution are prevented. Thereby, operation and maintenance of the lead storage battery are performed well.

Next, the capacity for a forklift is 280 A
4 shows specific comparison data of the liquid reduction amount and the charging time when the conventional semi-constant voltage charging method and the charging method of the present invention are applied to the lead storage battery of FIG. In this case, the use condition of the battery is such that the forklift is operated six days a week and the daily operation amount is 80% of the battery capacity. The operating environment temperature is 30 ± 10 ° C. Note that the first pattern charging in the constant current / constant voltage charging method of the present invention described below is a constant current in which the total charge in one charge is 101 to 110% of the previous total discharge of the storage battery. The second pattern charge is a constant current charge in which the total charge amount in one charge is 111 to 120% of the previous total discharge amount of the storage battery.

[1] Liquid reduction amount (1) Constant current / constant voltage / constant current charging Liquid reduction amount in case of 5 days charge in first charge pattern and 1 day charge in second charge pattern First charge Pattern → 7.8 ml / day × 5 days = 39 ml Second charge pattern → 14.2 ml / day × 1 day = 14.2 ml Total 53.2 ml Charge of first charge pattern 4 days, Charge of second charge pattern 2 days Volume of liquid reduction in case of 1st charge pattern → 7.8ml / day × 4 days = 31.2ml 2nd charge pattern → 14.2ml / day × 2days = 28.4ml Total 59.6ml Charge of 1st charge pattern 3 days The amount of liquid reduction in the case of 3 days of charging in the second charging pattern First charging pattern → 7.8 ml / day × 3 days = 23.4 ml Second charging pattern → 14.2 ml / day × 3 days = 42.6 ml Total 66.0 ml (2) Semi-constant voltage charging → 16.8 ml / day × 6 days = 100.8 ml From the above (1) and (2), the amount of liquid reduction when the method of the present invention is carried out is 53.2 to 66.0 ml. Quasi-static power Reduction liquid quantity when performing the charge was found to be 100.8ml,
It can be seen that the amount of liquid reduction is significantly reduced as compared with the conventional case.

[2] Charging time (1) Constant-current / constant-voltage / constant-current charging Charging of the first charging pattern 6 to 7 hours Charging of the second charging pattern 7 to 8 hours (2) Semi-constant voltage charging 10 ~ 12 hours From the above (1) and (2), one charging time when performing the method of the present invention is 6 to 8 hours, but one charging time when performing the conventional method is 10 to 12 hours, it can be seen that the charging time can be reduced according to the method of the present invention.

[0019]

As described above, according to the method of charging a lead storage battery of the present invention, the first charging pattern in which the constant current charging is performed at the first charging amount after the constant voltage charging at the constant current, The second that can generate gas at the end of charging because it is more than the charge amount of 1
And the second charging pattern for performing the constant current charging of the charging amount is used, and the number of times of charging using the first charging pattern within a predetermined period is set to be equal to or more than the number of times of charging using the second charging pattern. As a result, the charging time can be shortened and the interval between rehydration of the electrolytic solution can be increased as compared with the conventional quasi-constant voltage charging method. This allows
In particular, it is extremely effective when used for charging lead-acid batteries for electric vehicles.

[Brief description of the drawings]

FIG. 1 is a characteristic curve diagram showing charging characteristics of a first charging pattern used in an embodiment of the present invention.

FIG. 2 is a characteristic curve diagram showing charging characteristics of a second charging pattern used in an example of the present invention.

FIG. 3 is a characteristic curve diagram showing charging characteristics of conventional semi-constant voltage charging.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01M 10/42-10/48 H02J ⁷ /00-7/12

Claims (4)

(57) [Claims] 1. A method for charging a lead-acid battery requiring replenishment of an electrolyte, comprising: charging at a constant voltage after charging at a constant current; and performing constant-current charging at a first charge amount at the end of the constant-voltage charging. The constant-current charging of the second charge amount larger than the first charge amount at the end of the constant-voltage charge and capable of generating gas at the end of the charge is performed at the end of the constant-voltage charge. The charging is performed by selectively using the second charging pattern to be performed, and the number of times of charging using the first charging pattern within a predetermined period becomes equal to or more than the number of times of charging using the second charging pattern. A method of charging a lead storage battery, wherein the first charging pattern and the second charging pattern are selected as described above. 2. The method according to claim 1, wherein the first charge pattern is used.
The total charge amount per time is 101% to 1% of the total discharge amount of the storage battery.
2. The method for charging a lead storage battery according to claim 1, wherein the total charging amount at one time when the second charging pattern is used is 111% to 120% of the total discharging amount of the storage battery. 3. 3. A method for charging a lead-acid battery for an electric vehicle, which requires replenishment of an electrolyte, comprising: charging at a constant voltage after charging at a constant current; The first charge pattern and the constant current charge are followed by the constant voltage charge, and the second charge amount that is larger than the first charge amount at the end of the constant voltage charge and that can generate gas at the end of charge. The charging is performed by selectively using the second charging pattern for performing the current charging, and the number of days for performing the charging using the first charging pattern within a predetermined period is determined using the second charging pattern. A method of charging a lead storage battery for a storage battery, wherein the first charging pattern and the second charging pattern are selected so that the number of days for charging is longer than the number of days. 4. A method of charging a lead-acid storage battery which requires replenishment of an electrolytic solution, using a charging pattern in which constant-current charging is performed after constant-current charging, constant-voltage charging is performed, and then constant-current charging is performed again. When charging is performed n times within a predetermined period, the charge performed by increasing the charge amount of the last constant current charging so that gas is generated at the end of charging is more than n / 2 times. A method for charging a lead storage battery, wherein the method is performed a small number of times.