Lithium ion fast pulse charger
First Claim
Patent Images
1. A method of charging a battery implemented in a battery technology which has an electrochemically-determined maximum threshold voltage which must not be exceeded, comprising the steps of:
- (a.) applying intermittent current pulses to said battery, to intermittently produce a voltage at external terminals of said battery which is greater than said threshold voltage; and
(b.) thereafter operating a pass transistor as a linear regulator element to apply a clamped voltage to said battery which is approximately equal to said threshold voltage, wherein said pass transistor is integrated in a single package with said battery.
3 Assignments
0 Petitions
Accused Products
Abstract
A lithium-ion cell charging system wherein pulse charging (with excursions above the critical voltage) is followed (once average current has fallen low enough) by charging in a linear regulator mode, using a transistor internal to a battery pack as an element of a linear regulator.
-
Citations
18 Claims
-
1. A method of charging a battery implemented in a battery technology which has an electrochemically-determined maximum threshold voltage which must not be exceeded, comprising the steps of:
-
(a.) applying intermittent current pulses to said battery, to intermittently produce a voltage at external terminals of said battery which is greater than said threshold voltage; and (b.) thereafter operating a pass transistor as a linear regulator element to apply a clamped voltage to said battery which is approximately equal to said threshold voltage, wherein said pass transistor is integrated in a single package with said battery. - View Dependent Claims (2, 3, 4, 5, 6, 15)
-
-
7. A method of charging a lithium-containing battery which has a electrochemically-determined maximum threshold voltage which must not be exceeded, comprising the steps of:
-
(1.) applying current from a supply voltage which is greater than said threshold voltage, until the voltage seen across the battery reaches a first target voltage which is not substantially greater than said threshold voltage; (2.) applying intermittent current pulses to said battery from a supply voltage which is greater than said threshold voltage, to intermittently produce a voltage at external terminals of said battery, which is greater than said threshold voltage; (3.) thereafter operating a pass transistor intermittently as a linear regulator element, to intermittently apply a clamped voltage to said battery which is approximately equal to said threshold voltage; and (4.) thereafter operating said pass transistor continuously as a linear regulator element to apply a clamped voltage to said battery which is approximately equal to said threshold voltage, wherein said pass transistor is integrated in a single package with said battery. - View Dependent Claims (8, 9, 10, 16)
-
-
11. A battery charging system, comprising:
-
charging circuitry which operates in a first phase to intermittently apply current pulses to a battery, to intermittently produce a voltage, at external terminals of said battery, which is greater than a threshold voltage; and control circuitry, which operates in a second phase to operate a pass transistor as a linear regulator element to apply a clamped voltage to said battery which is approximately equal to said threshold voltage, wherein said pass transistor is integrated in a single package with said battery. - View Dependent Claims (12, 17)
-
-
13. A portable computer system, comprising:
-
memory, and a microprocessor operatively connected to read said memory, and at least one nonvolatile bulk data storage device, all located within a single chassis; a battery located within said chassis, and electrically connected to supply power to said memory under at least some circumstances; and charging circuitry, which operates in a first phase to intermittently apply current pulses to said battery, to intermittently produce a voltage at external terminals of said battery which is greater than a threshold voltage; and control circuitry which operates in a second phase to operate a pass transistor as a linear regulator element to apply a clamped voltage to said battery which is approximately equal to said threshold voltage, wherein said pass transistor is integrated in a single package with said battery. - View Dependent Claims (14, 18)
-
Specification