Systems and methods for monitoring characteristics of energy units

• US 10,330,732 B2
• Filed: 09/30/2016
• Issued: 06/25/2019
• Est. Priority Date: 10/01/2015
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Roumi, Farshid, Roumi, Mahshid
• Primary Examiner(s): Nguyen, Vincent Q
• Application Number:
  US15/282,982
• Publication Number:
  US 20170108552A1
• Time in Patent Office: 998 Days
• Field of Search: 324430-434, 320109
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/386 using test-loads
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults

Abstract

A system and method for monitoring characteristics of an electric energy device includes generating an external short from the electric energy device. The external short occurs at a known distance from a sensor and has at least one known external resistance. The received signal representing change in electromagnetic field due to the applied external short may be analyzed to determine a signal parameter that is then analyzed in comparison to a lookup table, based on the known conditions including distance, temperature and the external resistance. The output of this analyses in comparison with expected values may be utilized to identify a characteristic of the energy device.

Claims

1. A system for monitoring characteristics of an energy device, comprising:

a short generator coupled with the energy device adapted to generate an external short at a known resistance;

a sensor in communication with the short generator for sensing an induced varying electromagnetic field generated from the external short; and

,

a characteristic monitor adapted to analyze the induced varying electromagnetic field to determine a characteristic of the energy device, wherein;

the sensor being at a predetermined distance from the external short; and

the characteristic monitor determining the characteristic based at least on the predetermined distance.

2. The system of claim 1, the characteristic being one or more of:

state of charge of the energy device,

state of health of the energy device,

internal resistance or impedance of the energy device,

a short of the energy device, and

an abnormality of the energy device.

3. The system of claim 1, the short generator including a switch for activating the external short between a positive and negative terminal of the energy device.

4. The system of claim 1, the sensor including an electromagnetic coil.

5. The system of claim 1, the characteristic monitor being external to the energy unit.

6. The system of claim 1, the sensor being located with the characteristic monitor external the energy unit.

7. The system of claim 1, the characteristic monitor including a processor in communication with memory storing computer readable instructions that, when executed by the processor, operate to determine the characteristic, the processor being in communication with a communication interface adapted to modulate a DC voltage line coupled to the energy devices with a data signal including a configuration output based on the characteristic.

8. The system of claim 1, the characteristic monitor including a processor in communication with memory storing computer readable instructions that, when executed by the processor, operate to determine the characteristic, the memory storing a signal analyzer comprising computer readable instructions that, when executed by the processor, operate to analyze a received signal representing the induced varying electromagnetic field to generate a signal parameter based on system configuration information.

9. The system of claim 8, the system configuration information including one or more of information regarding the sensor, the known resistance, and a distance of the sensor to the external short.

10. The system of claim 8, the signal parameter including an instantaneous parameter.

11. The system of claim 10, the instantaneous parameter being a parameter chosen from the group of parameters including:

maximum power, maximum voltage square, maximum voltage, maximum change in voltage, maximum current, maximum current square, maximum change in current, full-width voltage at half maximum and current at half maximum.

12. The system of claim 10, the instantaneous parameter being based on a given time between 1 nanosecond and 10 microseconds of generation of the electrical short.

13. The system of claim 10, the instantaneous parameter being based on a given time between 10 nanoseconds and 1 microseconds of generation of the electrical short.

14. The system of claim 8, the signal parameter including an integrated parameter.

15. The system of claim 14, the integrated parameter being a parameter chosen from the group of parameters including:

total absolute energy and total absolute coulomb measured accumulatively over a period of time.

16. The system of claim 8, the signal parameter being based on:

17. The system of claim 8, the memory storing a state of charge analyzer comprising computer readable instructions that, when executed by the processor, analyze the signal parameter to determine a state of charge of the energy device.

18. The system of claim 17, the state of charge analyzer determining the state of charge of the energy device based upon the signal parameter compared to a lookup table stored within the memory.

19. The system of claim 18, the state of charge analyzer comparing a signal parameter to an expected device parameter value for the known resistance.

20. The system of claim 18, the lookup table including any one or more expected device parameters chosen from the group of expected device parameters including:

device brand, device manufacture, device model, device voltage, device C-rate, device material composition, expected device internal resistance, and device installation information.

21. The system of claim 20, the expected device parameters being configured for a plurality of distances between an external short and the sensor, and a plurality of known resistances of the external short.

22. The system of claim 17, the state of charge analyzer determining the state of charge of the energy device based upon the signal parameter compared to an energy device profile generated based on a previous received signal.

23. The system of claim 8, the memory storing a state of health analyzer comprising computer readable instructions that, when executed by the processor, analyze the signal parameter to determine a state of health of the energy device.

24. The system of claim 23, the state of health analyzer determining the state of health of the energy device based upon the signal parameter compared to a lookup table stored within the memory.

25. The system of claim 24, the lookup table including any one or more expected device parameters chosen from the group of expected device parameters including:

device brand, device manufacture, device model, device voltage, device C-rate, device material composition, expected device internal resistance, and device installation information.

26. The system of claim 25, the expected device parameters being configured for a plurality of distances between an external short and the sensor, and a plurality of known resistances of the external short.

27. The system of claim 23, one or more of:

the state of charge analyzer determining the state of charge of the energy device based upon the signal parameter compared to a energy device profile generated based on a previous received signal,

the state of health analyzer determining the state of health of the energy device based on comparing the signal parameter to the lookup table to determine if an internal resistance of the energy device is optimal,

the state of health analyzer determining the state of health of the energy device as an internal short when the signal parameter has a higher value than an expected device parameter within the lookup table,

the state of health analyzer determining the state of health of the energy device as a degraded life-span when the signal parameter has a lower value than an expected device parameter within the lookup table, and,

the state of health analyzer determining the state of health of the energy device by characterizing a short internal to the energy device.

28. The system of claim 27, the short internal to the energy device being characterized as a soft short when a total resistance value, including the internal resistance of the energy device and the known resistance, is above a hard-type threshold, but below a soft-type threshold, and the short internal to the energy device being characterized as a hard short when a total resistance value, including the internal resistance of the energy device and the known resistance, is at or below a hard-type threshold.

29. The system of claim 8, the memory storing a device configuration manager comprising computer readable instructions that, when executed by the processor, generate a configuration output for configuring the energy device.

30. The system of claim 29, the configuration output indicating one or more of:

a cycling rate for charging the energy device,

to bypass the energy device,

to disconnect the energy device,

a replacement date for the energy device,

a cell balancing configuration for the energy device, and

an adaptive charging configuration for the energy device.

31. An electric energy unit, comprising:

a plurality of electric energy devices coupled together between a positive voltage line and a negative voltage line;

an external short generator coupled to at least one of the electric energy devices; and

,

a switch coupled to each of the energy devices, the switch activated to alter the configuration of the plurality of energy devices in response to a determination based on an external short generated by the external short generator;

a sensor in communication with the external short generator for sensing an induced varying electromagnetic field generated from the external short; and

a characteristic monitor adapted to analyze the induced varying electromagnetic field to determine a characteristic of the at least one of the electric energy devices, wherein;

the sensor being at a predetermined distance from the external short; and

the characteristic monitor determining the characteristic based at least on the predetermined distance.

32. A method for monitoring characteristics of an electric energy device, comprising:

generating, by a short generator, an external short at the electric energy device with at least one known external resistance;

sensing, by a sensor, an induced varying electromagnetic field emitted due to the generated external short;

determining a signal parameter based on the induced varying electromagnetic field in the vicinity of the electric energy device; and

,

determining a characteristic of the electric energy device based on the signal parameter, wherein;

the sensor being at a predetermined distance from the external short; and

the characteristic of the electric energy device further being determined based on the predetermined distance.