Electricity: battery or capacitor charging or discharging – Serially connected batteries or cells – With discharge of cells or batteries
Patent
1993-11-03
1996-03-19
Wong, Peter S.
Electricity: battery or capacitor charging or discharging
Serially connected batteries or cells
With discharge of cells or batteries
320 24, H01M 1044, H01M 1046
Patent
active
055005845
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a battery charging method for charging a battery such as a lead acid storage battery quickly, and a battery charging apparatus used in carrying out said battery charging method.
TECHNICAL BACKGROUND
Conventionally, as a battery charging method, there are a constant-voltage charging method which applies a constant voltage to a battery for charging, and a constant-current charging method which applies a constant current continuously to the battery for charging. Though there are both merits and demerits in either of these methods, it is not easy to realize shortening of charging time considerably by any of existing methods.
In recent years, from a view point of environment protection, practical use of a so-called electromobile vehicle which uses the batteries as a driving source is strongly desired. For wide use of the electromobile, while it is necessary to shorten the battery charging time a great deal, the battery charging method which complies with this request sufficiently is still not developed at present.
Incidentally, a capacity of a battery is defined by an ampere-hour capacity (Ah) and an hour rate. For example, when the battery capacity of 10 Ah/10 hour rate is discharged at a current of 1 A, it can be used continuously for 10 hours. When this battery is discharged at a current of 4 A, while the continuous usable time is 2.5 hours by calculation, it takes, as a matter of fact, approximately 1.5 hours to reach the charge-end voltage. In the same way, when discharged at a current of 10 A, while the continuous usable time is 1 hour by calculation, a practical continuous usable time is approximately 35 minutes.
Similarly, this applies to charging, too. For example, when a battery of 10 Ah/10 hour rate capacity is charged at a constant current of 1 A for 10 hours, it reaches fully charged state. When it is charged at a constant current of 10 A, the chemical reaction in the battery proceeds faster than the calculation, and as a matter of fact, it approaches to the fully charged state by a half of the calculated time of one hour.
However, when the charging current is simply increased, it is liable to be overcharged and there is possibility of damaging electrodes of the battery. Moreover, there is a problem that only the surface of the electrodes is charged and the charging is not penetrated into the electrodes.
The present invention has been devised in view of the above-mentioned problems. It is the object, therefore, to provide a battery charging method and its apparatus which is able to charge in a very short item and to penetrate the charging into the electrodes without damaging a battery.
DISCLOSURE OF THE INVENTION
A battery charging method according to the present invention is characterized in that, an initial charging process for applying a charging current whose volume of electricity is increased gradually to start charging of a battery, a quick charging process for applying the charging current having the larger volume of electricity than the initial charging process intermittently to charge the battery while watching the battery terminal voltage, and a final charging process for applying the charging current whose volume of electricity is reduced gradually to finish charging of the battery, when the battery terminal voltage has reached a charge-end voltage, are carried out step-wise and continuously.
In a battery charging method claimed in claim 2, the battery defect is judged by watching the charging current in the initial charging process.
In a battery charging method claimed in claim 3, in the quick charging process, a continuous charging period during which the intermittent supply of charging current is continued, and a charging suspension period during which the intermittent supply of quick charging current is suspended, are repeated alternately till the battery terminal voltage reaches the charge-end voltage.
A battery charging apparatus-according to the present invention comprises, a control switch provided in a charging circuit, a c
REFERENCES:
patent: 4670703 (1987-06-01), Williams
Hanashiro Kiyomi
Tso Edward
Wong Peter S.
LandOfFree
Battery charging method and apparatus using initial charging ste does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Battery charging method and apparatus using initial charging ste, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Battery charging method and apparatus using initial charging ste will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1960532