Pulsed current battery management system

The present disclosure claims priority to U.S. Provisional Patent Application Ser. No. 63/179,946, filed Apr. 26, 2021, which is incorporated by reference herein in its entirety.

The present disclosure relates in general to circuits for electronic devices, including without limitation personal audio devices such as wireless telephones and media players, and more specifically, a pulsed current battery management system.

Portable electronic devices, including wireless telephones, such as mobile/cellular telephones, tablets, cordless telephones, mp3 players, smart watches, health monitors, and other consumer devices, are in widespread use. Such a portable electronic device may include a battery (e.g., a lithium-ion battery) for powering components of the portable electronic device. Typically, such batteries used in portable electronic devices are rechargeable, such that when charging, the battery converts electrical energy into chemical energy which may later be converted back into electrical energy for powering components of the portable electronic device.

Recharging of rechargeable batteries often involves trading off between charging rate and battery life cycle. For example, a high level of current delivered to the battery may increase a charge rate for a battery, but may degrade the useful life of the battery. Pulsed current charging may be used to maximize charging rate of a battery without degrading the useful life of a battery. However, the high peak-to-average current required from a pulsed-current charger may be beyond the limits of traditional battery chargers, such as USB chargers.

In accordance with the teachings of the present disclosure, one or more disadvantages and problems associated with existing approaches to battery charging may be reduced or eliminated.

In accordance with embodiments of the present disclosure, a battery management system, may include an input configured to couple to a power supply, an output configured to couple to a battery, and battery management circuitry coupled between the power supply and the battery and configured to deliver electrical energy to the output at a significantly higher peak-to-average power ratio than receipt of electrical energy to the input.

In accordance with these and other embodiments of the present disclosure, a method may include, with a battery management system coupled at an input of the battery management system to a power supply and coupled at an output of the battery management system to a battery; delivering electrical energy to the output at a significantly higher peak-to-average power ratio than receipt of electrical energy to the input.

Technical advantages of the present disclosure may be readily apparent to one skilled in the art from the figures, description and claims included herein. The objects and advantages of the embodiments will be realized and achieved at least by the elements, features, and combinations particularly pointed out in the claims.

It is to be understood that both the foregoing general description and the following detailed description are examples and explanatory and are not restrictive of the claims set forth in this disclosure.

A more complete understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:

FIG. 1 illustrates an example system for charging a battery, in accordance with embodiments of the present disclosure;

FIG. 2 illustrates an example pulsed current battery management system, in accordance with embodiments of the present disclosure;

FIG. 3 illustrates an example output current waveform for charging a battery, in accordance with embodiments of the present disclosure;

FIG. 4 illustrates another example pulsed current battery management system, in accordance with embodiments of the present disclosure; and

FIG. 5 illustrates yet another example pulsed current battery management system, in accordance with embodiments of the present disclosure.

FIG. 1 illustrates an example system 100 for charging a battery 102 , in accordance with embodiments of the present disclosure. As shown in FIG. 1 , system 100 may include battery 102 , a power supply 104 , and a battery management system 106 .

Battery 102 may include any system, device, or apparatus configured to convert chemical energy stored within battery 102 to electrical energy. For example, in some embodiments, battery 102 may be integral to a portable electronic device and battery 102 may be configured to deliver electrical energy to components of such portable electronic device. Further, battery 102 may also be configured to recharge, in which it may convert electrical energy received by battery 102 into chemical energy to be stored for later conversion back into electrical energy. As an example, in some embodiments, battery 102 may comprise a lithium-ion battery.

Power supply 104 may include any system, device, or apparatus configured to supply electrical energy to battery management system 106 . In some embodiments, power supply 104 may include a direct-current (DC) power source configured to deliver electrical energy at a substantially constant voltage. Accordingly, a peak-to-average power delivered from power supply 104 may be approximately equal to 1. In some of such embodiments, power supply 104 may include an alternating current (AC)-to-DC converter/adapter, configured to convert an AC voltage (e.g., provided by an electrical socket installed in the wall of a building) into a DC voltage. In some embodiments, power supply 104 may be power limited in terms of a maximum amount of power that may be drawn from power supply 104 .

Battery management system 106 may include any system, device, or apparatus configured to receive electrical energy from power supply 104 and control delivery of such energy to battery 102 , such that battery 102 may be charged using pulsed current charging, in a manner in which a peak-to-average power delivered from battery management system 106 to battery 102 may be significantly greater than 1 (e.g., 2 or more). In some embodiments, battery management system 106 may comprise a battery charger, configured to deliver electrical energy to battery 102 in order that battery 102 converts the electrical energy to chemical energy that is stored in battery 102 . In some embodiments, battery management system 106 may include a wired charger configured to draw electrical energy from an electrical power outlet or from a power bank. In other embodiments, battery management system 106 may include a wireless charger configured to draw electrical energy via inductive coupling from a wireless charging pad or similar device.

FIG. 2 illustrates an example pulsed current battery management system 106 A (coupled to a power supply 104 and a battery 102 ), in accordance with embodiments of the present disclosure. In some embodiments, pulsed current battery management system 106 A shown in FIG. 2 may be used to implement battery management system 106 of FIG. 1 . As shown in FIG. 2 , pulsed current battery management system 106 A may include a first power converter 202 , an energy reservoir 204 , a second power converter 206 , a current controller 208 , a battery monitor 210 , and a sense resistor 212 .

First power converter 202 may include any system, device, or apparatus configured to receive electrical energy from power supply 104 and use such received electrical energy to charge energy reservoir 204 . In some embodiments, first power converter 202 may comprise a capacitive power converter or “charge pump.” In other embodiments, first power converter 202 may comprise an inductor-based power converter (e.g., a buck converter, a buck-boost converter, or a boost converter).

Although FIG. 2 depicts power converter 202 interfaced between power supply 104 and energy reservoir 204 , in some embodiments, power supply 104 may be coupled directly to energy reservoir 204 and thus configured to directly charge energy reservoir 204 .

In some embodiments, a bandwidth of power converter 202 may be designed or chosen that enables a trade-off between the peak-to-average current from power supply 104 and a maximum peak current/power that may be delivered to battery 102 .

Energy reservoir 204 may include any system, device, or apparatus configured to store electrical energy. For example, in some embodiments, energy reservoir 204 may comprise one or more capacitors. As another example, in some embodiments, energy reservoir 204 may comprise one or more batteries.

Second power converter 206 may include any system, device, or apparatus configured to, under the control of current controller 208 , transfer electrical energy from energy reservoir 204 to battery 102 and use such received electrical energy to charge battery 102 by way of an output current I OUT delivered from second power converter 206 to battery 102 . In some embodiments, second power converter 206 may comprise a capacitive power converter or “charge pump.” In other embodiments, second power converter 206 may comprise an inductor-based power converter (e.g., a buck converter, a buck-boost converter, or a boost converter).

Current controller 208 may include any system, device, or apparatus configured to, based on a sense voltage V SNS indicative of output current I OUT and a target current waveform I TGT , control second power converter 206 (e.g., by controlling operation of switches internal to second power converter 206 ) in order to regulate output current I OUT in accordance with target current waveform I TGT . In some embodiments, current controller 208 may control output current I OUT to have a pulsed waveform such that the power transfer from power converter 206 to battery 102 has a high peak-to-average power over time. For example, in some embodiments, output current I OUT may be a square wave with a defined peak amplitude IPEAK, defined period T, and defined duty cycle DUTY, as shown in FIG. 3 . However, in other embodiments, output current I OUT may include a waveform of a different shape, including without limitation a triangular waveform, a sine wave, or any suitable combination of pulsed periodic waveforms.

Battery monitor 210 may include any system, device, or apparatus configured to monitor operational parameters associated with battery 102 (e.g., battery voltage, battery current, and battery temperature) and based on such operational parameters, estimate one or more battery conditions (e.g., battery state of charge, battery state of health, battery impedance, and internal chemical state of battery 102 ) associated with battery 102 . Such estimations may be made based on an estimate of electrochemical impedance spectroscopy or a physics-based model of battery 102 . Further, based on the operational parameters and/or battery conditions, battery monitor 210 may generate a target current waveform I TGT for charging battery 102 . The algorithm for generating target current waveform I TGT is beyond the scope of this disclosure, but may comprise any suitable algorithm for optimizing (including for optimizing for tradeoffs) target current waveform I TGT in terms of efficiency, charge rate, battery useful life, and/or other factors. For example, such algorithm may seek to control output current I OUT to maximize charge rate while maintaining temperature and/or other parameters/conditions of battery 102 within safe operational limits. Further, in some embodiments, battery monitor 210 may embed signals within target current waveform I TGT designed to assist with obtaining operational parameters and/or estimate battery conditions.

Accordingly, current controller 208 and battery monitor 210 may operate in concert to adapt output current I OUT in accordance with operational parameters and conditions of battery 102 . Such adaptation may attempt to minimize an effective impedance of battery 102 , control a temperature associated with battery 102 , and/or other parameters. In some embodiments, battery monitor 210 may perform monitoring of battery 102 , estimation of conditions, and/or adapt output current I OUT while battery 102 is charging and/or when battery 102 is under load from a load powered by battery 102 .

Sense resistor 212 may include any system, device, or apparatus configured to generate a sense voltage V SNS indicative of output current I OUT , in accordance with Ohm's law.

FIG. 4 illustrates an example pulsed current battery management system 106 B (coupled to a power supply 104 , a battery 102 , and a system load 402 of battery 102 ), in accordance with embodiments of the present disclosure. In some embodiments, pulsed current battery management system 106 B shown in FIG. 4 may be used to implement battery management system 106 of FIG. 1 . Pulsed current battery management system 106 B shown in FIG. 4 may be similar in many respects to pulsed current battery management system 106 A shown in FIG. 2 . Accordingly, only certain differences between pulsed current battery management system 106 B and pulsed current battery management system 106 A are discussed below.

For example, as shown in FIG. 4 , pulsed current battery management system 106 B may include a third power converter 404 coupled between the output of second power converter 206 and a system load 402 of battery 102 . System load 402 may represent one or more components (e.g., of a portable electronic device including battery 102 ) configured to be powered from battery 102 .

Third power converter 404 may include any system, device, or apparatus configured to transfer electrical energy from the output of second power converter 206 to system load 402 . Further, in the architecture shown in FIG. 4 , third power converter 404 may also transfer electrical energy from battery 102 to system load 402 . In some embodiments, third power converter 404 may comprise a capacitive power converter or “charge pump.” In other embodiments, third power converter 404 may comprise an inductor-based power converter (e.g., a buck converter, a buck-boost converter, or a boost converter).

Although FIG. 4 depicts third power converter 404 coupled between the output of second power converter 206 and system load 402 of battery 102 , in other embodiments, third power converter 404 may instead be coupled between energy reservoir 204 and system load 402 of battery 102 , such that third power converter 404 is configured to transfer electrical energy from energy reservoir 204 to system load 402 . In yet other embodiments, third power converter 404 may instead be coupled between power supply 104 and system load 402 of battery 102 , such that third power converter 404 is configured to transfer electrical energy from power supply 104 to system load 402 .

In any event, in these architectures, current controller 208 may control only a current delivered to battery 102 , but does not control current delivered to system load 402 .

FIG. 5 illustrates an example pulsed current battery management system 106 C (coupled to a power supply 104 , a battery 102 , and a system load 502 of battery 102 ), in accordance with embodiments of the present disclosure. In some embodiments, pulsed current battery management system 106 C shown in FIG. 5 may be used to implement battery management system 106 of FIG. 1 . Pulsed current battery management system 106 C shown in FIG. 5 may be similar in many respects to pulsed current battery management system 106 A shown in FIG. 2 . Accordingly, only certain differences between pulsed current battery management system 106 C and pulsed current battery management system 106 A are discussed below.

For example, as shown in FIG. 5 , pulsed current battery management system 106 C may include a third power converter 504 coupled directly between battery 102 and a system load 502 of battery 102 . System load 502 may represent one or more components (e.g., of a portable electronic device including battery 102 ) configured to be powered from battery 102 .

Third power converter 504 may include any system, device, or apparatus configured to, transfer electrical energy from the output of battery 102 to system load 502 . In addition, third power converter 504 may also transfer electrical energy from the output of second power converter 206 to system load 502 . In some embodiments, third power converter 504 may comprise a capacitive power converter or “charge pump.” In other embodiments, third power converter 504 may comprise an inductor-based power converter (e.g., a buck converter, a buck-boost converter, or a boost converter).

A notable difference between pulsed current battery management system 106 C shown in FIG. 5 versus pulsed current battery management system 106 B shown in FIG. 4 is that in pulsed current battery management system 106 C, current controller 208 may control only the sum of the current delivered to battery 102 and the current delivered to system load 502 . Thus, in pulsed current battery management system 106 C, when an output current limit of power converter 206 is exceeded, battery 102 may also provide electrical energy to system load 502 , in addition to electrical energy provided by power converter 206 .

As used herein, when two or more elements are referred to as “coupled” to one another, such term indicates that such two or more elements are in electronic communication or mechanical communication, as applicable, whether connected indirectly or directly, with or without intervening elements.

This disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Similarly, where appropriate, the appended claims encompass all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Moreover, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, or component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. Accordingly, modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein without departing from the scope of the disclosure. For example, the components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses disclosed herein may be performed by more, fewer, or other components and the methods described may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. As used in this document, “each” refers to each member of a set or each member of a subset of a set.

Although exemplary embodiments are illustrated in the figures and described below, the principles of the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should in no way be limited to the exemplary implementations and techniques illustrated in the drawings and described above.

Unless otherwise specifically noted, articles depicted in the drawings are not necessarily drawn to scale.

All examples and conditional language recited herein are intended for pedagogical objects to aid the reader in understanding the disclosure and the concepts contributed by the inventor to furthering the art, and are construed as being without limitation to such specifically recited examples and conditions. Although embodiments of the present disclosure have been described in detail, it should be understood that various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the disclosure.

Although specific advantages have been enumerated above, various embodiments may include some, none, or all of the enumerated advantages. Additionally, other technical advantages may become readily apparent to one of ordinary skill in the art after review of the foregoing figures and description.

To aid the Patent Office and any readers of any patent issued on this application in interpreting the claims appended hereto, applicants wish to note that they do not intend any of the appended claims or claim elements to invoke 35 U.S.C. § 112(f) unless the words “means for” or “step for” are explicitly used in the particular claim.