Traction battery leakage detection system for electrified vehicle

• US 9,783,060 B2
• Filed: 05/15/2014
• Issued: 10/10/2017
• Est. Priority Date: 05/15/2014
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Chang, Xiaoguang, Wang, Xu, He, Chuan
• Primary Examiner(s): Ruddock, Ula C
• Assistant Examiner(s): AMPONSAH, OSEI K
• Application Number:
  US14/278,590
• Publication Number:
  US 20150333378A1
• Time in Patent Office: 1,244 Days
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/02 to electric heating circuits
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/24 Steering angle
• CPC Class Codes: B60L 2240/34 Cabin temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: G01R 27/025 Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: G01R 31/52 : Testing for short-circuits, leakage current or ground faults
• CPC Class Codes: H01M 10/4228 : Leak testing of cells or batteries
• CPC Class Codes: H01M 10/4285 : Testing apparatus
• CPC Class Codes: H01M 10/48 : Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 2220/20 : Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 : Electric charging stations
• CPC Class Codes: Y02T 90/14 : Plug-in electric vehicles

Abstract

A leakage detection system for a battery pack of a vehicle may include detection circuitry having a first side connecting a positive terminal of the pack to ground and a second side connecting a negative terminal of the pack to ground, and including no more than one switch among the sides. The system may also include measurement circuitry configured to measure a voltage across a resistor of one of the sides when the switch is open and closed, and a controller programmed to output a leakage associated with the battery pack based on the voltage.

Claims

1. A leakage detection system for a battery pack of a vehicle comprising:

detection circuitry having a first side connecting a positive terminal of the pack to ground and a second side connecting a negative terminal of the pack to ground, and including no more than one switch among the sides;

measurement circuitry configured to measure a voltage at a resistor of one of the sides when the switch is open and closed; and

a controller programmed to control the switch to open and close according to at least one trigger event, and to output a leakage associated with the battery pack based on the voltage at the resistor when the switch is open and closed according to the trigger event,

wherein the switch and measurement circuitry are disposed on opposite ones of the sides of the detection circuitry.

2. The system of claim 1, wherein the controller is further programmed to output the leakage based on a leakage resistance at each of the first and second sides of the detection circuitry.

3. The system of claim 1, wherein the controller is further programmed to apply a filter to the voltage prior to outputting the leakage.

4. The system of claim 3, wherein the filter is a moving average filter.

5. The system of claim 1, wherein the trigger event includes an expiration of a predefined amount of time.

6. A battery leakage detection system comprising:

detection circuitry having first and second battery sides, and including one switch and a measurement circuitry disposed on a side opposite the switch;

and a controller programmed to control the switch to open and close according to a trigger event, and to output a leakage associated with the battery based on a voltage at a resistor of the measurement circuitry when the switch is opened and closed.

7. The system of claim 6, wherein the trigger event includes an expiration of a predefined amount of time.

8. The system of claim 6, wherein the controller is further programmed to output the leakage based on a leakage resistance at each of the first and second sides of the detection circuitry.

9. The system of claim 6, wherein the controller is further programmed to apply a filter to the voltage prior to outputting the leakage.

10. The system of claim 9, wherein the filter is a moving average filter.