Battery charger and method utilizing alternating DC charging current
First Claim
Patent Images
1. A battery charger comprising:
- a pair of battery charger terminals; and
a microprocessor controlled battery charging circuit to supply a battery charging current to a battery connected across the pair of battery charger terminals,wherein said microprocessor controlled battery charging circuit periodically measures a voltage across the pair of battery charger terminals, defining a measured voltage,wherein said microprocessor controlled battery charging circuit does not supply the battery charging current when the measured voltage is less than a first predetermined voltage,wherein said microprocessor controlled battery charging circuit operates in (1) a first charging cycle mode while the measured voltage is greater than said first predetermined voltage and less than a second predetermined voltage, and (2) a second charging cycle mode while the measured voltage is greater than or equal to said second predetermined voltage,wherein said first charging cycle mode comprises two DC charging values, each having a non-zero average DC value defining a maximum charging current value and a minimum charging current value, said microprocessor controlled battery charging circuit alternating the battery charging current between said maximum charging current value and said minimum charging current value until said battery voltage reaches said second predetermined voltage,wherein said maximum charging current value (1) ramps up from said minimum charging current value to said maximum level charging current or (2) ramps down from said maximum charging current value to said minimum charging current value.
9 Assignments
0 Petitions
Accused Products
Abstract
A battery charger is disclosed for use with various batteries, such as automotive- and marine-type batteries. In accordance with an aspect of the invention, the charging current is alternated between non-zero DC charging current levels. By alternating the charging current between non-zero DC charging levels, the battery can be charged to a higher capacity (i.e., ampere hours) faster, thus reducing the charging time and at the same time allow the rating of the battery charger to be increased. In accordance with another important aspect of the invention, the technique for alternating the charging current can be implemented in both linear- and switched-mode battery chargers.
28 Citations
20 Claims
-
1. A battery charger comprising:
-
a pair of battery charger terminals; and a microprocessor controlled battery charging circuit to supply a battery charging current to a battery connected across the pair of battery charger terminals, wherein said microprocessor controlled battery charging circuit periodically measures a voltage across the pair of battery charger terminals, defining a measured voltage, wherein said microprocessor controlled battery charging circuit does not supply the battery charging current when the measured voltage is less than a first predetermined voltage, wherein said microprocessor controlled battery charging circuit operates in (1) a first charging cycle mode while the measured voltage is greater than said first predetermined voltage and less than a second predetermined voltage, and (2) a second charging cycle mode while the measured voltage is greater than or equal to said second predetermined voltage, wherein said first charging cycle mode comprises two DC charging values, each having a non-zero average DC value defining a maximum charging current value and a minimum charging current value, said microprocessor controlled battery charging circuit alternating the battery charging current between said maximum charging current value and said minimum charging current value until said battery voltage reaches said second predetermined voltage, wherein said maximum charging current value (1) ramps up from said minimum charging current value to said maximum level charging current or (2) ramps down from said maximum charging current value to said minimum charging current value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A method for charging a battery, the method comprising the steps of:
-
periodically measuring a voltage across a pair of battery charger terminals, defining a measured voltage; supplying the battery charging current across the pair of battery charger terminals when the measured voltage is greater than a first predetermined voltage; operating in a first charging cycle mode while the measured voltage is greater than said first predetermined voltage and less than a second predetermined voltage; and operating in a second charging cycle mode while the measured voltage is greater than or equal to said second predetermined voltage, wherein said first charging cycle mode comprises two DC charging values, each having a non-zero average DC value defining a maximum charging current value and a minimum charging current value, said microprocessor controlled battery charging circuit alternating the battery charging current between said maximum charging current value and said minimum charging current value until said battery voltage reaches said second predetermined voltage, wherein said maximum charging current value (1) ramps up from said minimum charging current value to said maximum level charging current or (2) ramps down from said maximum charging current value to said minimum charging current value. - View Dependent Claims (16)
-
-
17. A battery charger comprising:
-
a pair of battery charger terminals; and a microprocessor controlled battery charging circuit to provides a plurality of selectable charging modes, at least one of said plurality of selectable charging modes being a fast charge mode, wherein said microprocessor controlled battery charging circuit periodically measures a voltage across the pair of battery charger terminals, defining a measured voltage, wherein said microprocessor controlled battery charging circuit does not supply the battery charging current when the measured voltage is less than a first predetermined voltage, wherein, in said fast charge mode, the battery charger alternates between two different DC charging currents, wherein said DC charging currents have a non-zero average value and define a maximum charging current value and a minimum charging current value, said microprocessor controlled battery charging circuit alternating the battery charging current between said maximum charging current value and said minimum charging current value until said battery'"'"'s battery voltage exceeds a second predetermined voltage, and charges said battery at a constant current thereafter, said DC charging currents selected to cause said battery to be at least partially charged during said fast charging cycle at a voltage greater than said second predetermined voltage, wherein said maximum charging current value (1) ramps up from said minimum charging current value to said maximum level charging current or (2) ramps down from said maximum charging current value to said minimum charging current value. - View Dependent Claims (18, 19, 20)
-
Specification