# US 12,113,390 B2 · Battery charging system and method using dynamically adjusted battery voltage threshold for switching charging modes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,113,390 B2 - Document ID: US12113390B2 - Status: Granted - Kind: B2 - Application number: 17/607,357 - Filed: 2020-05-19 - Published: 2022-07-14 - Granted: 2024-10-08 - Earliest claimed: 2019-05-23 - Assignees: The University of Hong Kong - Applicants: The University of Hong Kong - Inventors: Shu Yuen Ron Hui; Yun Yang - Web page: https://patentgrep.com/patent/US12113390B2 ## CPC - H02J 7/342: {The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging (with circuits for polarity protection H02J7/68)} - H02J 7/96: in response to battery voltage - H02J 7/82: Control of state of charge [SOC] - H02J 7/84: Control of state of health [SOH] - H02J 7/953: {in response to charge current gradient} - H02J 7/963: {in response to battery voltage gradient} - H02J 50/12: of the resonant type - H02M 3/33573: {Full-bridge at primary side of an isolation transformer} - H02M 3/33576: {having at least one active switching element at the secondary side of an isolation transformer} - H02J 2207/20: Charging or discharging characterised by the power electronics converter - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) ## Abstract A battery charging system determines a current condition of a battery in real time and dynamically determine a threshold voltage for controlling a charging mode of the battery based on the current battery condition. The battery charging system charges the battery using a constant current (CC) mode or constant voltage (CV) mode based on the battery voltage and the dynamically determined threshold voltage. The battery charging system can determine the voltage and current of the battery in real time without receiving information on the battery from the power receiving side of the battery charging system. ## Claims ### Claim 1 A battery charging system for charging a battery, comprising: a charging circuit configured to charge the battery; and a controller communicatively coupled with the charging circuit, wherein the controller is configured to: determine a current condition of the battery, wherein the current condition comprises a current state-of-health (SoH) or a maximum state-of-charge (SoCmax) of the battery; dynamically determine a threshold voltage for controlling a charging mode of the charging circuit, based on the current condition; determine a battery voltage of the battery during charging; configure the charging circuit to charge the battery using a constant current (CC) mode when the battery voltage is less than the threshold voltage; and configure the charging circuit to charge the battery using a constant voltage (CV) mode when the battery voltage is equal to or greater than the threshold voltage. ### Claim 2 (depends on 1) The battery charging system of claim 1, wherein the controller is further configured to determine the threshold voltage based on SoH or SoCmax. ### Claim 3 (depends on 1) The battery charging system of claim 1, wherein the charging circuit comprises: a transmitter-side portion configured to transmit power wirelessly; and a receiver-side portion configured to wirelessly receive power from the transmitter-side portion and charge the battery without providing control feedback to the transmitter-side portion. ### Claim 4 (depends on 3) The battery charging system of claim 3, wherein: the transmitter-side portion comprises a series compensated circuit; and the receiver-side portion comprises a series compensated circuit. ### Claim 5 (depends on 3) The battery charging system of claim 3, wherein: the receiver-side portion comprises a series compensated circuit; and the transmitter-side portion comprises a parallel compensated circuit. ### Claim 6 (depends on 3) The battery charging system of claim 3, wherein: the receiver-side portion comprises a series compensated circuit; and the transmitter-side portion comprises an inductive-capacitive-capacitive (LCC) compensated circuit. ### Claim 7 (depends on 3) The battery charging system of claim 3, wherein: the receiver-side portion comprises a series compensated circuit; and the transmitter-side portion comprises an inductive-capacitive-inductive (LCL) compensated circuit. ### Claim 8 (depends on 3) The battery charging system of claim 3, wherein the receiver-side portion comprises a rectifier that is configured to charge the battery without using a charging management circuit between the rectifier and the battery. ### Claim 9 (depends on 3) The battery charging system of claim 3, wherein the transmitter-side portion comprises a coil resonator and at least one sensor configured to monitor a primary voltage and a primary current of the coil resonator; and wherein the controller is further configured to: estimate a voltage and a current of the battery based on the primary voltage and the primary current; and determine the condition of the battery based on the estimated voltage and the estimated current of the battery. ### Claim 10 (depends on 9) The battery charging system of claim 9, wherein the controller is further configured to determine the voltage and the current of the battery without receiving information on the battery from the receiver-side portion. ### Claim 11 (depends on 9) The battery charging system of claim 9, wherein the transmitter-side portion comprises a power inverter that is controlled by a plurality of switching signals, and wherein the controller is further configured to control a phase-shift angle of the plurality of switching signals to control the primary current and the primary voltage. ### Claim 12 (depends on 11) The battery charging system of claim 11, wherein the power inverter is configured to operate at a same switching frequency when charging the battery in the CC mode and the CV mode according to the phase-shift angle of the plurality of switching signals. ### Claim 13 (depends on 12) The battery charging system of claim 12, wherein the switching frequency is substantially equal to a resonant frequency of the coil resonator. ### Claim 14 (depends on 11) The battery charging system of claim 11, wherein a resonant frequency of the coil resonator of the transmitter-side portion is substantially equal to a resonant frequency of a coil resonator of the receiver-side portion. ### Claim 15 A battery charging method comprising: determining a current condition of a battery, wherein the current condition comprises a current state-of-health (SoH) or a maximum state-of-charge (SoCmax) of the battery; dynamically determining a threshold voltage for controlling a charging mode of the battery based on the current condition; determining a battery voltage of the battery during charging; charging the battery using a constant current (CC) mode when the battery voltage is less than the threshold voltage; and charging the battery using a constant voltage (CV) mode when the battery voltage is equal to or greater than the threshold voltage. ### Claim 16 (depends on 15) The method of claim 15, wherein the dynamically determining the threshold voltage comprises determining the threshold voltage based on SoH or SoCmax. ### Claim 17 (depends on 15) The method of claim 15, further comprising: transmitting power wirelessly at a transmitter-side portion of a charger; and receiving the power wirelessly at a receiver-side portion of the charger that is configured to charge the battery without providing control feedback to the transmitter-side portion. ### Claim 18 (depends on 17) The method of claim 17, wherein: transmitting the power using a series compensated circuit included in the transmitter-side portion; and receiving the power using a series compensated circuit included in the receiver-side portion. ### Claim 19 (depends on 17) The method of claim 17, wherein: transmitting the power using a parallel compensated circuit included in the transmitter-side portion; and receiving the power using a series compensated circuit included in the receiver-side portion. ### Claim 20 (depends on 17) The method of claim 17, wherein: transmitting the power using an inductive-capacitive-capacitive (LCC) compensated circuit included in the transmitter-side portion; and receiving the power using a series compensated circuit included in the receiver-side portion. ### Claim 21 (depends on 17) The method of claim 17, wherein: transmitting the power using an inductive-capacitive-inductive (LCL) compensated circuit included in the transmitter-side portion; and receiving the power using a series compensated circuit included in the receiver-side portion. ### Claim 22 (depends on 17) The method of claim 17, further comprising charging the battery without using a charging management circuit between a rectifier of the receiver-side portion and the battery. ### Claim 23 (depends on 17) The method of claim 17, further comprising: monitoring a primary voltage and a primary current of a coil resonator of the transmitter-side portion; estimating a voltage and a current of the battery based on the primary voltage and the primary current; and determining the condition of the battery based on the estimated voltage and the estimated current of the battery. ### Claim 24 (depends on 23) The method of claim 23, further comprising: determining the voltage and the current of the battery without receiving information on the battery from the receiver-side portion. ### Claim 25 (depends on 23) The method of claim 23, further comprising: controlling a power inverter of the transmitter-side portion using a plurality of switching signals, and controlling a phase-shift angle of the plurality of switching signals to control the primary current and the primary voltage. ### Claim 26 (depends on 25) The method of claim 25, further comprising: operating the power inverter at a same switching frequency when charging the battery in the CC mode and the CV mode according to the phase-shift angle of the plurality of switching signals. ### Claim 27 (depends on 26) The method of claim 26, wherein the switching frequency is substantially equal to a resonant frequency of the coil resonator.