Systems and methods for monitoring batteries in user devices
Systems and methods for monitoring batteries in user devices are disclosed. The user devices include mobile phones and laptops, in examples. The system includes a micro-electro-mechanical system (MEMS) ultrasound source, a MEMS ultrasound sensor, a signal drive and acquisition module (SDM), and a processor. The MEMS source and sensor are included within the user device and are disposed against the battery. The SDM configures the MEMS source to transmit an ultrasound pulse into the battery, and the MEMS sensor detects ultrasound reflected by or transmitted through the battery. The SDM collects the detected pulses, and the processor analyzes the detected pulses to determine states of the battery including a state of health, a state of charge and an instantaneous battery thickness measurement. For example, the SDM and the processor can be included within the user device, and/or the SDM and the signal processor can be incorporated into an integrated circuit.
1 . A system for monitoring a battery within a user device, the system comprising:
a micro-electro-mechanical system (MEMS) ultrasound source and a MEMS ultrasound sensor that are each included within the user device and are disposed against the battery; and
one or more computing units comprising a battery management system, a signal drive and acquisition module (SDM), and a processor,
wherein the SDM includes a controller, a memory, an excitation module, and a receiver module,
wherein the excitation module is configured by the controller to transmit an excitation signal to the MEMS ultrasound source, the MEMS ultrasound source is configured to transmit an ultrasound pulse into the battery in response to receiving the excitation signal, and the MEMS ultrasound sensor is configured by the controller to detect the ultrasound pulse from the battery and to generate a response signal associated with the detected ultrasound that is received by the receiver module;
wherein the processor is configured to access the receiver module, analyze the response signal, and determine different states of the battery in response to the analysis, the determined states including an instantaneous thickness measurement of the battery, and
wherein the one or more computing units are configured to:
compare the determined instantaneous thickness measurement to one or more predetermined thresholds; and
adjust operation of the battery responsive to the comparison.
2 . The system of claim 1 , wherein the MEMS ultrasound source and the MEMS ultrasound sensor are disposed against a same surface of the battery, and the MEMS ultrasound sensor detects ultrasound pulses reflected from an interior of the battery.
3 . The system of claim 1 , wherein:
the MEMS ultrasound source is disposed against a first surface of the battery;
the MEMS ultrasound sensor is disposed against a second surface of the battery that opposes the first surface; and
the MEMS ultrasound sensor detects ultrasound transmitted through the battery.
4 . The system of claim 1 , wherein the MEMS ultrasound source and the MEMS ultrasound sensor are capacitive micromachined ultrasonic transducers (CMUT) or piezoelectric micromachined ultrasonic transducers (PMUT).
5 . The system of claim 1 , wherein each of the one or more computing units is included within the user device.
6 . The system of claim 1 , wherein the SDM and the processor are incorporated into a same integrated circuit.
7 . The system of claim 1 , wherein the determined states further include a state of charge (SOC), a state of health (SOH), and a temperature of the battery.
8 . The system of claim 1 , wherein the memory includes a set of feature rules that define one or more features for the processor to extract from the response signal during the analysis of the response signal.
9 . The system of claim 1 , wherein the one or more predetermined thresholds comprise a first threshold corresponding to normal irreversible swelling of the battery, and adjusting operation of the battery comprises adjusting charging parameters so as to extend a life of the battery.
10 . The system of claim 1 , wherein the one or more predetermined thresholds comprise a second threshold corresponding to abnormal irreversible swelling of the battery, and adjusting operation of the battery comprises disabling the battery or ceasing charging of the battery.
11 . The system of claim 1 , wherein the one or more predetermined thresholds comprise a plurality of stored thresholds, each stored threshold corresponding to a different state of charge or different charge/discharge cycle number of a reference battery, and the one or more computing units are further configured to select one of the plurality of stored thresholds for the comparing based on a state of charge or charge/discharge cycle number for the battery in the user device.
12 . A method for monitoring a battery within a user device using a micro-electro-mechanical system (MEMS) ultrasound source and MEMS ultrasound sensor disposed against the battery and within the user device, the method comprising:
transmitting an excitation signal to the MEMS ultrasound source such that the MEMS ultrasound source transmits an ultrasound pulse into the battery in response to the excitation signal;
detecting the ultrasound pulse from the battery via the MEMS ultrasound sensor and generating a response signal associated with the detected ultrasound;
analyzing the response signal and determining different states of the battery in response to the analyzing, the determined states including an instantaneous thickness measurement of the battery;
comparing the determined instantaneous thickness measurement to one or more predetermined thresholds; and
adjusting operation of the battery responsive to the comparing.
13 . The method of claim 12 , wherein:
the MEMS ultrasound source and the MEMS ultrasound sensor are disposed against a same surface of the battery, and
the MEMS ultrasound sensor detects ultrasound pulses reflected from an interior of the battery.
14 . The method of claim 12 , wherein:
the MEMS ultrasound source is disposed against a first surface of the battery,
the MEMS ultrasound sensor is disposed against a second surface of the battery that opposes the first surface, and
the MEMS ultrasound sensor detects ultrasound transmitted through the battery.
15 . The method of claim 12 , wherein the MEMS ultrasound source and the MEMS ultrasound sensor are capacitive micromachined ultrasonic transducers (CMUT) or piezoelectric micromachined ultrasonic transducers (PMUT).
16 . The method of claim 12 , wherein at least the analyzing the response signal is performed by a processor included within the user device.
17 . The method of claim 12 , wherein the determined states further include a state of charge (SOC), a state of health (SOH), and a temperature of the battery.
18 . The method of claim 12 , wherein the determined states further include:
a lifetime thickness measurement of the battery, determined from one or more instantaneous thickness measurements of the battery obtained over time.
19 . The method of claim 12 , wherein the one or more predetermined thresholds comprise a first threshold corresponding to a normal irreversible swelling of the battery, and the adjusting operation of the battery comprises adjusting charging parameters so as to extend a life of the battery.
20 . The method of claim 12 , wherein the one or more predetermined thresholds comprise a second threshold corresponding to abnormal irreversible swelling of the battery, and the adjusting operation of the battery comprises disabling the battery or ceasing charging of the battery.
21 . The method of claim 12 , wherein:
the one or more predetermined thresholds comprise a plurality of stored thresholds, each stored threshold corresponding to a different state of charge or different charge/discharge cycle number of a reference battery, and
the method further comprises selecting one of the plurality of stored thresholds for the comparing based on a state of charge or charge/discharge cycle number for the battery in the user device.
22 . The method of claim 12 , wherein:
the ultrasound pulse transmitted into the battery has a wavelength less than a thickness of the battery; or
a near field boundary separating a Fresnel region and a Fraunhofer region of the transmitted ultrasound pulse occurs within the battery.