Adjusting battery charging curves based on

Abstract

A method of adjusting a battery charge profile of a battery may include monitoring one or more parameters associated with the battery during normal operation of a device powered by the battery and while the battery is simultaneously charged by a charger and discharged by a dynamic system load of the device, an impedance of the battery is determined based on the one or more parameters, a condition of the battery is determined based on the impedance and the one or more parameters, and a battery charging profile is adjusted based on the condition.

Description

Technical Field

[0001] The present disclosure relates generally to circuits for electronic devices, including but not limited to personal devices such as wireless telephones and media players, and more particularly to a battery charging system in which a battery charging curve is adjusted in the field based on measured parameters when the battery-powered device is operating normally. Background Art

[0002] Portable electronic devices, including wireless telephones such as mobile / cellular telephones, tablet computers, cordless phones, mp3 players, smart watches, health monitors, and other consumer devices, are becoming widely used. Such portable electronic devices may include batteries (e.g., lithium-ion batteries) for powering components of the portable electronic devices. Typically, such batteries used in portable electronic devices are rechargeable, such that when charged, the battery converts electrical energy into chemical energy, which can then be converted back into electrical energy for powering components of the portable electronic device.

[0003] Rechargeable batteries are typically charged according to a charging curve to achieve efficient charging and operation of such batteries. Summary of the invention

[0004] According to the teachings of the present disclosure, one or more disadvantages and problems associated with existing battery charging approaches may be reduced or eliminated.

[0005] According to an embodiment of the present disclosure, a method for adjusting a battery charging curve of a battery may include: monitoring one or more parameters associated with a battery during normal operation of a device powered by the battery and while the battery is simultaneously charged by a charger and discharged by a dynamic system load of the device, determining an impedance of the battery based on the one or more parameters, determining a condition of the battery based on the impedance and the one or more parameters, and adjusting the battery charging curve based on the condition.

[0006] According to these and other embodiments of the present disclosure, a system for adjusting a battery charging curve of a battery may include: a monitoring circuit and a battery condition estimator, the monitoring circuit being configured to monitor one or more parameters associated with the battery during normal operation of a device powered by the battery and while the battery is simultaneously charged by a charger and discharged by a dynamic system load of the device, and the battery condition estimator being configured to determine an impedance of the battery based on the one or more parameters, determine a condition of the battery based on the impedance and the one or more parameters, and adjust the battery charging curve based on the condition.

[0007] The technical advantages of the present disclosure can be easily seen by those skilled in the art from the drawings, descriptions and claims included herein. The objects and advantages of the embodiments will be realized and completed at least by the elements, features and combinations specifically pointed out in the claims.

[0008] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the present disclosure, as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] A more complete understanding of the present embodiments and their advantages may be obtained by referring to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals indicate like features, and wherein:

[0010] Figure 1 An example block diagram illustrating selected components of a system for charging a battery of an electronic device according to an embodiment of the present disclosure;

[0011] Figure 2 shows an example of a charging curve of a battery of a battery-powered device according to an embodiment of the present disclosure;

[0012] Figure 3 An example charging waveform of a smartphone being charged by a USB-PD wall charger according to an embodiment of the present disclosure is shown;

[0013] Figure 4 shows an example charging curve for temporarily discharging a battery during charging of a battery-powered device using a battery test circuit according to an embodiment of the present disclosure; and

[0014] Figure 5 The broadband dynamic load from a smartphone executing a video playback application is shown according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0015] According to an embodiment of the present disclosure, Figure 1 An example block diagram of selected components of a system 98 for charging a battery 240 of a battery powered device 200 is shown. The battery powered device 200 may include any suitable electronic device, including but not limited to a mobile phone, a smart phone, a tablet / laptop, a media player, a handheld device, a smart watch, a game controller, etc.

[0016] like Figure 1As shown, one or more external components 100 may be coupled to the battery-powered device 200 wirelessly or via a wire or cable. Such one or more external components 100 may include an external charger, such as a wall charger 111 and / or a wireless charger 120. Such one or more external components 100 may additionally or alternatively include an accessory 112 (e.g., an earbud charging case) powered by the battery-powered device 200 and / or an accessory 121 (e.g., a smart watch) wirelessly powered by the battery-powered device 200. Figure 1 As shown, the battery powered device 200 may include a device charging path 210 to an internal battery 240 and a power path from the battery 240 to a system load 230 of the battery powered device 200. Such a system load 230 may include a processor, a display, an audio speaker, and / or one or more other electrical or electronic components.

[0017] The battery 240 may include any system, device, or apparatus configured to convert chemical energy stored in the battery 240 into electrical energy. For example, in some embodiments, the battery 240 may be integrated into the battery-powered device 200, and the battery 240 may be configured to deliver electrical energy to the system load 230 and other components of the battery-powered device 200. In addition, the battery 240 may also be configured to be recharged, wherein it may convert the electrical energy received by the battery 240 from the main charger 214 and / or the parallel charger 213 into chemical energy for later conversion back into electrical energy. For example, in some embodiments, the battery 240 may include a lithium-ion battery. The battery 240 may include a single battery, a plurality of batteries connected in series, a plurality of batteries connected in parallel, or a combination of a plurality of batteries connected in series and in parallel.

[0018] The device charging path 210 may include a wired power port 212 configured to receive power from an external wall charger 111 via a power cord and / or to deliver power to an accessory 112 via a power cord. The wired power port 212 may be a Universal Serial Bus (USB) Type C / Power Delivery (USB-C / PD) port, and the wall charger 111 may be a USB-PD charger with a programmable voltage between 5 volts and 20 volts. However, any suitable type of port and charger may be employed. The device charging path 210 may additionally or alternatively include a wireless power port 211 configured to receive power from an external wireless charger 120 and / or to deliver power to an accessory 121 via wireless transmission. In some embodiments, the wireless charger 120 may include a Qi-compatible charger.

[0019] The power received by the device charging path 210 from any port 211, 212 can be converted to system-level power by the main charger 214 and / or by the second parallel charger 213 of the battery-powered device 200. The main charger 214 may include any system, device or apparatus configured to receive control signals and power from the wall charger 111 and / or the wireless charger 120 when the battery-powered device 200 is coupled to the wall charger 111 and / or the wireless charger 120, and control the delivery of such energy to the battery 240, the system load 230 and / or other components of the battery-powered device 200. For example, in some embodiments, the main charger 214 may include an inductor-based power converter. However, any suitable regulator may be used to implement the main charger 214, including but not limited to a switched capacitor regulator, a hybrid regulator, and a multi-level regulator. The parallel charger 213 may include a secondary inductive charger or a switched capacitor charger that supplements the main charger 214 during the high-speed charging stage.

[0020] The charging path 210 can deliver power from the chargers 214 and 213 to the system load 230 and the battery 240 at the same time. The power supplied to / from the battery 240 can be decoupled from the system power supply by controlling a power field effect transistor (FET) 215 connected in series with the battery 240. The FET 215 can be configured to control the precise current / voltage to the battery 240 under the operation of the main charger 214.

[0021] In some cases, the FET 215 can be fully turned on, and the power exchange between the charger 214, 213, the system load 230, and the battery 240 can be completely controlled by the demand of the system load 230, the state of the battery 240, and the current limit of the charger 214, 213. For example, during charging of the battery 240, when the peak power demand of the system load 230 exceeds the charger current limit, the battery 240 can temporarily provide power to the system load 230. The battery 240 can receive power from the external charger 111, 120, or the battery 240 can provide power back to the accessories 112, 121. In the latter case, the charger 214, 213, the wired power port 212, and / or the wireless power port 211 can transfer their energy in reverse.

[0022] When at least one of the ports 211, 212 is reverse charging (i.e., charging an external accessory 112 or 121), power can be transferred between the ports 211, 212 (assuming at least one of the ports 211 and 212 is powering the battery-powered device 200), or accessory power can be supplied from the battery 240 to the charging ports 211, 212, or a combination of both. When the external charger 111, 120 is active, the battery 240 can be charged and discharged simultaneously according to the power requirements of the system load 230 and the external accessories 112, 121.

[0023] The battery powered device 200 may further include a battery monitoring circuit 217 configured to monitor a battery current I flowing through the battery 240. BAT , the voltage V across the battery 240 BAT , the temperature of the battery 240, and / or other parameters associated with the battery 240. The battery monitoring circuit 217 may be embedded within the battery pack of the battery 240, or it may be located external to such a battery pack. The battery powered device 200 may also include a sense resistor 216 to allow the battery monitoring circuit 217 to accurately monitor the current battery current I BAT .

[0024] The main charger 214 may charge the battery 240 according to a charging algorithm. According to the charging algorithm, the battery condition estimator 218 may receive a monitoring signal from the battery monitoring circuit 217 to estimate the condition of the battery 240, and adjust the charging curve 219 of the battery in response to the estimated battery condition, the limitations of the external chargers 111, 120, and the charging strategy. In some embodiments, the main charger 214 may communicate with power elements of the charging system and power elements outside the charging system to define power exchange between the power elements.

[0025] Control of the charging profile 219 may involve communication between the main charger 214 and the external chargers 111, 120 to negotiate power transfer parameters. Control of the charging profile 219 may also involve changing the conversion ratio, current limit, and / or power limit of the device chargers 214, 213, and / or adjusting the control of the FET 215 for the battery 240. In addition, control of the charging profile 219 may involve switching elements of the device charging path 210 on or off and / or routing power through specific paths at different stages of the charging profile.

[0026] The estimate of the battery condition by the battery condition estimator 218 may include an estimate of the state of charge (SOC) and / or state of health (SOH) of the battery 240. In some embodiments, such an estimate may include "coulomb counting," the process of tracking the amount of charge delivered to and extracted from the battery 240. More complex algorithms may include estimates of one or more detailed states of the battery 240, such as the impedance of the battery 240, the internal potential of the battery 240, an estimate of the electrochemical state of the battery 240 (e.g., the ion concentration profile of the battery 240), and / or other estimates of side reactions of the primary redox reaction of the battery 240.

[0027] although Figure 1 Not shown, the battery 240 may also include other protection circuits (eg, fuses, protection FETs, etc.).

[0028] Figure 2 2 shows an example of a charging curve 219A of a battery 240 of a battery powered device 200 according to an embodiment of the present disclosure. Figure 2 In the depicted example charging curve 219A, the charging current I delivered by the chargers 214 and 213 is CHG There may be multiple constant current steps followed by a final constant voltage step. The timing of switching between current steps may be adjusted based on an estimate of the condition of the battery 240 generated by the battery condition estimator 218 , where the condition of the battery 240 includes the SOC of the battery 240 .

[0029] Figure 3 FIG. 2 shows an example charging waveform of a USB-PD wall charger (which may implement the wall charger 111) charging a smartphone (which may implement the battery powered device 200) according to an embodiment of the present disclosure. Figure 3 In the example of , a charging algorithm implemented by the battery condition estimator 218 controls the charging curve 219 to generate a current pulse on the battery 240 at the beginning of charging to determine the condition of the battery, where the condition is the impedance of the battery 240. The battery condition estimator 240 can then adjust the charging curve 219 based on the estimate of the initial condition.

[0030] In some embodiments, the battery powered device 200 may include an auxiliary battery test circuit 220 to help determine the condition of the battery 240. The battery test circuit 220 may include a ground resistor, a current sink, a current source, and / or a combination of multiple elements. In some embodiments, the battery test circuit 220 may be programmed under the control of the main charger 214. For example, the current level and timing of the current sink may be controlled by the main charger 214. In some embodiments, the battery test circuit 220 may apply a current pulse with a duration between 100 microseconds and 10 seconds to the battery 240 to help determine the impedance of the battery 240.

[0031] Figure 4 FIG. 2 shows an example charging curve 219B according to an embodiment of the present disclosure, which utilizes the battery test circuit 220 to temporarily discharge the battery 240 during charging of the battery-powered device 200. Figure 4 As shown, the battery test circuit 220 can momentarily interrupt the current or load of the battery 240 while the battery 240 is charging. Figure 4 In the charging curve 219B, the positive current charges the battery 240, while the negative current pulse discharges the battery 240.

[0032] like Figure 1 As shown, when the battery-powered device 200 is in operation, the system load 230 of the battery-powered device 200 may include a dynamic load 232. For example, if the battery-powered device 200 is a smart phone, the dynamic load 232 may include a load from an application processor, a display driver, and / or an audio speaker. Figure 1 As shown, the system load 230 may include a power converter 231 configured to convert power supplied by the chargers 213 , 214 and / or the battery 240 into a regulated power supply expected by the system load 230 .

[0033] In some embodiments, the dynamic load 232 may be a broadband dynamic load. For example, Figure 5 A broadband dynamic load from a smartphone executing a video playback application is shown according to an embodiment of the present disclosure. The battery condition estimator 218 can use any suitable approach to estimate the impedance of the battery 240 based on the sensed monitoring parameters associated with the broadband dynamic load. For example, systems and methods for estimating battery impedance from a broadband dynamic load are disclosed in U.S. patent application serial number 17 / 463,998 filed on September 1, 2021 and U.S. patent application serial number 17 / 463,980 filed on September 1, 2021, both of which are incorporated herein by reference in their entirety.

[0034] Embodiments of the present disclosure may combine one or more of the above systems and methods to adjust the charging curve (e.g., charging curve 219) of a battery (e.g., battery 240) that is simultaneously charged by a charger (e.g., main charger 214, parallel charger 213) and discharged by a system load (e.g., system load 230). According to embodiments of the present disclosure, the battery condition estimator 218 may change the charging curve 219 to intentionally stimulate the battery 240 to estimate the impedance of the battery 240, and / or may control the dedicated battery test circuit 220 to intentionally create a transient load on the battery 240 to determine the impedance of the battery 240. However, other embodiments of the present disclosure may not require determining the impedance of the battery 240 as a condition for adjusting the charging curve 219 of the battery 240. Instead, such embodiments may rely on the broadband characteristics of the dynamic system load 230 to stimulate the battery 240 in order to estimate the impedance of the battery 240 that is being charged and discharged simultaneously. The broadband dynamic load may estimate the impedance of the battery 240 over a wide frequency range (e.g., 1 mHz to 1 MHz).

[0035] Utilizing the broadband nature of the dynamic system load 232 can have many advantages. Non-limiting examples of such advantages compared to other approaches can include:

[0036] Reduction in circuitry (e.g., battery test circuit 220 may not be required) and simplification of charging path requirements (e.g., no need to create current pulses through device charging path 210);

[0037] Power efficiency (e.g., no current sink required for estimation purposes);

[0038] Reduction of charging time (e.g., no need to introduce a charger current pulse at the beginning of charging);

[0039] A more accurate estimate of battery condition, since impedance can be continuously estimated from a broadband load as a stimulus; and

[0040] Algorithmic advantages, such as using battery impedance estimation to determine the available power of the battery 240.

[0041] Embodiments of the present disclosure provide systems and methods for adjusting a battery charging profile of a battery based on measured parameters associated with the battery during normal operation of a battery-powered device powered by the battery. As used herein, "normal operation" may be defined as the battery-powered device operating in accordance with its intended end-use function, such that parameters are measured and charging profiles are adjusted in the field, rather than measuring parameters or adjusting charging profiles offline or during a dedicated calibration mode of the battery-powered device.

[0042] In some embodiments, the system and method may include simultaneously charging the battery through a charger and discharging the battery through a dynamic system load. During at least the same time period, a device charging path for charging the battery through the charger and a load path for discharging the battery through a dynamic system load are activated. The combined current and battery terminal voltage from the activated charging and load paths can be monitored. The impedance of the battery is determined by the combined current. The condition of the battery can be determined based on the combined current, the battery terminal voltage, and the determined impedance. Discharging the battery by the dynamic system load can indicate that the charging system is purely self-powered and that no additional stimulus needs to be added to the battery to identify the impedance.

[0043] Determining the condition of the battery may also involve reconfiguring elements of the charging path based on the determined impedance. The dynamic system load may be a broadband load. The system and method for adjusting the battery charging curve of the battery may also include monitoring the temperature of the battery. The determination of the condition of the battery may be based on the monitored combined current, the monitored battery terminal voltage, and the monitored temperature of the battery. The determination of the battery condition may also involve utilizing coulomb counting in order to determine the condition of the battery. The determination of the battery condition may also be based on the impedance determined from the step of determining the impedance.

[0044] The battery charging profile may be adjusted based on one or more of: the condition of the battery, the power capability of the power path; and / or user dependent battery management conditions.

[0045] The system and method for adjusting a battery charging profile may also include an external power sink coupled to the charger and powering the external power sink through the reverse operating charging path. The charger may communicate with power elements of a charging system including a charging path and a load path, and may also communicate with external power elements of the charging system to define a power exchange.

[0046] The impedance of the battery can be determined by stimulating the battery with transient events generated by transient charging curves and / or transient power / power dissipation events from dedicated battery test circuits (operating with dynamic system loads).

[0047] As used herein, when two or more elements are referred to as being “coupled” to each other, the term indicates that the two or more elements are in electronic or mechanical communication, as applicable, whether indirectly or directly, with or without intervening elements.

[0048] The present disclosure covers all changes, substitutions, variations, alterations and modifications to the example embodiments herein that will be understood by a person of ordinary skill in the art. Similarly, where appropriate, the appended claims cover all changes, substitutions, variations, alterations and modifications to the example embodiments herein that will be understood by a person of ordinary skill in the art. In addition, in the appended claims, references to a device or system or a component of a device or system adapted to, arranged to, capable of, configured to, enabled to, operable to, or operable to perform a specific function include the device, system or component, regardless of whether it or the specific function is activated, turned on or unlocked, as long as the device, system or component is so adapted, arranged, capable, configured, enabled, operable or operable. Therefore, without departing from the scope of the present disclosure, the systems, devices and methods described herein may be modified, added or omitted. For example, the components of the systems and devices may be integrated or separated. In addition, the operations of the systems and devices disclosed herein may be performed by more, fewer or other components, and the described methods may include more, fewer, or other steps. In addition, the 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.

[0049] Although exemplary embodiments are shown in the drawings 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 not be limited in any way to the exemplary implementations and techniques shown in the drawings and described above.

[0050] Unless specifically noted otherwise, items depicted in the drawings are not necessarily drawn to scale.

[0051] All examples and conditional language listed herein are intended for teaching purposes to help readers understand the present disclosure and the concepts contributed by the inventors to further advance the art, and are interpreted as not being limited to these specific examples and conditions. Although the embodiments of the present disclosure have been described in detail, it should be understood that various changes, substitutions and modifications may be made thereto without departing from the spirit and scope of the present disclosure.

[0052] Although specific advantages have been listed above, various embodiments may include some, none, or all of the listed advantages. In addition, other technical advantages may become apparent to those of ordinary skill in the art after reviewing the above drawings and descriptions.

[0053] To assist the Patent Office and any reader of any patent issuing based upon this application in interpreting the claims appended hereto, applicants wish to note that unless the phrase “means for” or “step for” is expressly used in a particular claim, they do not intend for any of the appended claims or claim elements to invoke 35 U.S.C. §112(f).

Claims

1. A method for adjusting a battery charging curve, the method comprising: monitoring one or more parameters associated with the battery during normal operation of a device powered by the battery and while the battery is simultaneously charged by a charger and discharged by a dynamic system load of the device; determining an impedance of the battery based on the one or more parameters; determining a condition of the battery based on the impedance and the one or more parameters; as well as The battery charging profile is adjusted based on the condition.

2. The method according to claim 1, wherein: The one or more parameters include one or more of a current associated with the battery, a voltage associated with the battery, and a temperature associated with the battery.

3. The method according to claim 1 or 2, wherein: The condition is the state of charge of the battery.

4. The method according to claim 1 or 2, wherein: The condition is the state of health of the battery.

5. The method according to claim 1 or 2, wherein: The condition is the amount of charge delivered to and extracted from the battery.

6. The method according to any one of claims 1 to 5, further comprising coupling an external power consumer to the charger and supplying power to the external power consumer by the charger operating in reverse.

7. The method according to any one of claims 1 to 6, wherein: Determining the impedance of the battery includes stimulating the battery with one or more of transient events generated by a transient charge curve and transient power supply / power drain events from a dedicated battery test circuit and operating with the dynamic system load.

8. The method according to any one of claims 1 to 6, wherein: Determining the impedance of the battery includes reconfiguring elements of a charging path of the device based on the impedance.

9. The method according to any one of claims 1 to 8, wherein: The dynamic system load is a broadband load.

10. The method according to any one of claims 1 to 9, wherein: Adjusting the battery charging profile further includes adjusting the charging profile based on one or more of a power capability of a power path of the device and a user dependent battery management condition.

11. The method according to any one of claims 1 to 10, further comprising the charger communicating with power elements of a charging system and power elements external to the charging system in order to define power exchanges between the power elements.

12. A system for adjusting a battery charging curve of a battery, the system comprising: a monitoring circuit configured to monitor one or more parameters associated with the battery during normal operation of a device powered by the battery and while the battery is simultaneously charged by a charger and discharged by a dynamic system load of the device; and A battery condition estimator, the battery condition estimator being configured to: determining an impedance of the battery based on the one or more parameters; determining a condition of the battery based on the impedance and the one or more parameters; as well as The battery charging curve is adjusted according to the condition.

13. The system according to claim 12, wherein: The one or more parameters include one or more of a current associated with the battery, a voltage associated with the battery, and a temperature associated with the battery.

14. The system according to claim 12 or 13, wherein: The condition is the state of charge of the battery.

15. The system according to claim 12 or 13, wherein: The condition is the state of health of the battery.

16. The system according to claim 12 or 13, wherein: The condition is the amount of charge delivered to and extracted from the battery.

17. The system of any one of claims 12 to 16, further comprising an external power consumer coupled to the charger and configured to power the external power consumer via the charger operating in reverse.

18. A system according to any one of claims 12 to 17, wherein: Determining the impedance of the battery includes stimulating the battery with one or more of transient events generated by a transient charge curve and transient power supply / power drain events from a dedicated battery test circuit and operating with the dynamic system load.

19. A system according to any one of claims 12 to 18, wherein: Determining the impedance of the battery includes reconfiguring elements of a charging path of the device based on the impedance.

20. The system according to any one of claims 12 to 19, wherein: The dynamic system load is a broadband load.

21. A system according to any one of claims 12 to 20, wherein: Adjusting the battery charging profile further includes adjusting the charging profile based on one or more of a power capability of a power path of the device and a user dependent battery management condition.

22. The system of any one of claims 12 to 21, further comprising the charger configured to communicate with power elements of a charging system and power elements external to the charging system in order to define power exchanges between the power elements.

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