Battery tester with databus

[0002] The present application is based on and claims the benefit of U.S. provisional patent application Serial No. 60/192,222, filed Mar. 27, 2000, the content of which is hereby incorporated by reference in its entirety.

[0003] The present invention relates to battery testers of the type used to test storage batteries. More specifically, the present invention relates to a modular battery tester capable of interfacing with other types of test equipment.

[0004] Various types of battery testers are known in the art. One type of battery tester is based upon the measurement of a dynamic parameter, such as dynamic conductance. Examples of various battery testers and monitors are forth in U.S. Pat. No. 3,873,911, issued Mar. 25, 1975, to Champlin, entitled ELECTRONIC BATTERY TESTING DEVICE; U.S. Pat. No. 3,909,708, issued Sep. 30, 1975, to Champlin, entitled ELECTRONIC BATTERY TESTING DEVICE; U.S. Pat. No. 4,816,768, issued Mar. 28, 1989, to Champlin, entitled ELECTRONIC BATTERY TESTING DEVICE; U.S. Pat. No. 4,825,170, issued Apr. 25, 1989, to Champlin, entitled ELECTRONIC BATTERY TESTING DEVICE WITH AUTOMATIC VOLTAGE SCALING; U.S. Pat. No. 4,881,038, issued Nov. 14, 1989, to Champlin, entitled ELECTRONIC BATTERY TESTING DEVICE WITH AUTOMATIC VOLTAGE SCALING TO DETERMINE DYNAMIC CONDUCTANCE; U.S. Pat. No. 4,912,416, issued Mar. 27, 1990, to Champlin, entitled ELECTRONIC BATTERY TESTING DEVICE WITH STATE-OF-CHARGE COMPENSATION; U.S. Pat. No. 5,140,269, issued Aug. 18, 1992, to Champlin, entitled ELECTRONIC TESTER FOR ASSESSING BATTERY/CELL CAPACITY; U.S. Pat. No. 5,343,380, issued Aug. 30, 1994, entitled METHOD AND APPARATUS FOR SUPPRESSING TIME VARYING SIGNALS IN BATTERIES UNDERGOING CHARGING OR DISCHARGING; U.S. Pat. No. 5,572,136, issued Nov. 5, 1996, entitled ELECTRONIC BATTERY TESTER WITH AUTOMATIC COMPENSATION FOR LOW STATE-OF-CHARGE; U.S. Pat. No. 5,574,355, issued Nov. 12, 1996, entitled METHOD AND APPARATUS FOR DETECTION AND CONTROL OF THERMAL RUNAWAY IN A BATTERY UNDER CHARGE; U.S. Pat. No. 5,585,728, issued Dec. 17, 1996, entitled ELECTRONIC BATTERY TESTER WITH AUTOMATIC COMPENSATION FOR LOW STATE-OF-CHARGE; U.S. Pat. No. 5,592,093, issued Jan. 7, 1997, entitled ELECTRONIC BATTERY TESTING DEVICE LOOSE TERMINAL CONNECTION DETECTION VIA A COMPARISON CIRCUIT; U.S. Pat. No. 5,598,098, issued Jan. 28, 1997, entitled ELECTRONIC BATTERY TESTER WITH VERY HIGH NOISE IMMUNITY; U.S. Pat. No. 5,757,192, issued May 26, 1998, entitled METHOD AND APPARATUS FOR DETECTING A BAD CELL IN A STORAGE BATTERY; U.S. Pat. No. 5,821,756, issued Oct. 13, 1998, entitled ELECTRONIC BATTERY TESTER WITH TAILORED COMPENSATION FOR LOW STATE-OF-CHARGE; U.S. Pat. No. 5,831,435, issued Nov. 3, 1998, entitled BATTERY TESTER FOR JIS STANDARD; U.S. Pat. No. 5,914,605, issued Jun. 22, 1999, entitled ELECTRONIC BATTERY TESTER; U.S. Pat. No. 5,945,829, issued Aug. 31, 1999, entitled MIDPOINT BATTERY MONITORING; U.S. Pat. No. 6,002,238, issued Dec. 14, 1999, entitled METHOD AND APPARATUS FOR MEASURING COMPLEX IMPEDANCE OF CELLS AND BATTERIES; U.S. Pat. No. 6,037,777, issued Mar. 14, 2000, entitled METHOD AND APPARATUS FOR DETERMINING BATTERY PROPERTIES FROM COMPLEX IMPEDANCE/ADMITTANCE; U.S. Pat. No. 6,051,976, issued Apr. 18, 2000, entitled METHOD AND APPARATUS FOR AUDITING A BATTERY TEST; U.S. Pat. No. 6,081,098, issued Jun. 27, 2000, entitled METHOD AND APPARATUS FOR CHARGING A BATTERY; U.S. Pat. No. 6,091,245, issued Jul. 18, 2000, entitled METHOD AND APPARATUS FOR AUDITING A BATTERY TEST; U.S. Pat. No. 6,104,167, issued Aug. 15, 2000, entitled METHOD AND APPARATUS FOR CHARGING A BATTERY; U.S. Pat. No. 6,137,269, issued Oct. 24, 2000, entitled METHOD AND APPARATUS FOR ELECTRONICALLY EVALUATING THE INTERNAL TEMPERATURE OF AN ELECTROCHEMICAL CELL OR BATTERY; U.S. Pat. No. 6,163,156, issued Dec. 19, 2000, entitled ELECTRICAL CONNECTION FOR ELECTRONIC BATTERY TESTER; U.S. Pat. No. 6,172,483, issued Jan. 9, 2001, entitled METHOD AND APPARATUS FOR MEASURING COMPLEX IMPEDANCE OF CELL AND BATTERIES; and U.S. Pat. No. 6,172,505, issued Jan. 9, 2001, entitled ELECTRONIC BATTERY TESTER.

[0005] In general, battery testing techniques have used a single, integrated stand-alone unit.

[0006] An electronic battery tester includes battery test circuitry configured to couple to a battery, a memory configured to log data from the battery test circuitry, and a databus configured to exchange logged data with external circuitry. In various embodiments, the battery test circuitry includes memory for storing raw data. The databus is capable of coupling to an external device such as a hand-held device. The logged data can be transferred over the databus for subsequent processing in the external device. Example databuses include both hard wired buses as well as transmission using infrared, radio waves, etc.

[0007] In one aspect, an external microprocessor based system is provided to couple to a databus and receive logged data from battery test circuitry.

[0008] FIG. 1 is a simplified block diagram showing battery test circuitry coupled to external circuitry through a databus.

[0009] FIG. 2

[0010] FIG. 3 is a simplified block diagram showing battery test circuitry.

[0011] FIG. 4 is a simplified block diagram of external circuitry configured to couple to the battery test circuitry of FIG. 3.

[0012] Typically, battery testers have been stand-alone units. The present invention provides a battery tester 10 such as that illustrated in FIG. 1 which includes a databus 12 for coupling to external circuitry 14. Battery tester 10 is configured to couple to storage battery 16 through electrical connectors 18 to perform a battery test on battery 16. Connectors 18 can be, for example, Kelvin type connectors. Typically, test circuitry 10 will obtain a dynamic parameter of the battery using an AC forcing function. Examples include dynamic conductance, resistance, admittance, impedance, their combinations, or others. However, any type of battery test can be performed including battery testing which involves application of large loads, or application of large currents or voltages such as through a charger, simple voltage measurements, etc. In one embodiment, the battery tester 10 is permanently mounted in a automotive vehicle such as the type of vehicle that uses a internal combustion engine or an electric engine.

[0013] Databus 12 is used to exchange information with external circuitry 14. Such information includes, for example, raw data measurements and conclusions of battery tester 10, and inputs, such as user inputs and other sensor inputs into battery tester 10. Further, external circuitry 14 can control battery tester 10 through databus 12 and provide information such as a battery rating to battery tester 10 for use in performing a battery test. Databus 12 can be a proprietary databus or can be in accordance with known standards such as RS232, CAN, ISA, PCI, PCMCIA, etc. Battery tester 10 can be configured to communicate with portable devices such as portable notebook computers, PDAs (Personal Data Assistants) such as a Palm Pilot™, etc. The databus 12 can also be configured to interface with other types of equipment which are used in the automotive industry such as “scan” tools which are used to interface with the on-board computer in a vehicle. Such scan tools are known in the art and are used to perform diagnostics and retrieve information from the on-board computer. In such an embodiment, databus 12 can be in accordance with the databus used in OBD (on-board diagnostic) systems.

[0014] The battery tester 10 of FIG. 1 can be a modular component of a scan tool formed by external circuitry 14. In another aspect of the invention as illustrated in FIG. 2, the battery tester 10 is an integral component of a scan tool 20. FIG. 2 also illustrates a second databus 22 which is used to couple to an on-board computer of a vehicle.

[0015] In embodiments which utilize a scan tool, an operator is able to perform a battery test using the same scan tool used for diagnosing other conditions of the vehicle. Further, the scan tool can selectively instruct an operator to perform a battery test or control operation of the battery test based upon data retrieved from the on-board vehicle computer system through bus 22. This can be part of an overall diagnostic system used to provide more accurate diagnostics of the vehicle. In one embodiment, the battery test circuitry requires information through bus 22 or monitors the flow of information on a databus of the vehicle. The test circuit can obtain information about battery type, battery rating, and charge history. Additionally, if the vehicle contains an internal battery tester, information regarding battery tests or battery measurements can be obtained or monitored through bus 22. In such an embodiment, test circuit 10 does not need to perform a battery test itself, or couple to the battery.

[0016] FIG. 3 is a more detailed block diagram of battery test circuitry 10 which includes a forcing function 40 and an amplifier 42 coupled to connectors 18. In the illustration of FIG. 3, connectors 18 are shown as Kelvin connections. The forcing function 40 can be any type of signal which has a time varying component including a transient signal. The forcing function can be through application of a load or by applying an active signal to battery 16. A response signal is sensed by amplifier 42 and provided to analog to digital converter 44 which couples to microprocessor 46. Microprocessor 46 operates in accordance with instructions stored in memory 48. In accordance with the invention, microprocessor 46 can store data into memory 48.

[0017] Input/output (I/O) is provided for coupling to the databus 12. I/O 102 can be in accordance with the desired standard or protocol as described above. Data collected by battery test circuitry 10 can be stored in memory 48 and transmitted over bus 12 when pulled by external circuitry 14. In one embodiment, input/output 52 comprises an RF (Radio Frequency) or IR (Infrared) input/output circuit and bus 12 comprises electromagnetic radiation. The logged data can comprise individual measurement points such as voltage and/or current measurements, either static or dynamic. Additionally, the logged data can comprise time and data information, operating conditions such as temperature, charge, etc. In addition to logging raw data, calculated data such as calculated conductance or battery condition, battery state of health, battery state of charge, etc. can be logged.

[0018] Of course, the illustration of FIG. 3 is simply one simplified embodiment and other embodiments are in accordance with the invention. Databus 12 may be capable of coupling directly to memory 48 for retrieval of stored data. Additionally, in the illustrated embodiment microprocessor 46 is configured to measure a dynamic parameter based upon the forcing function 40. This dynamic parameter can be correlated with battery condition as set forth in the above-mentioned Champlin and Midtronics, Inc. patents. However, other types of battery tests circuitry can be used in the present invention and certain aspects of the invention should not be limited to the specific embodiment illustrated herein. FIG. 3 also illustrates an optional input/output block 50 which can be any other type of input and/or output coupled to microprocessor 46. For example, this can be used to couple to external devices or to facilitate user input and/or output. Databus 12 can also be used to provide data or instructions to microprocessor 46. This can instruct the microprocessor 46 to perform a certain test, transmit specified data, update programming instructions, constant test parameters, etc. stored in memory 48. Although a microprocessor 46 is shown, other types of computational or other circuitry can be used to collect and place data into memory 48.

[0019] FIG. 4 is a more detailed block diagram of external circuitry 14. External circuitry 14 includes input/output (I/O) circuitry 150 for coupling to databus 12. Again, if databus 12 is through a nonphysical connections such as infrared or radio frequency, I/O circuitry 150 should operate accordingly. A microprocessor 152 couples to memory 154 and operates at a rate determined by a system clock 156. Microprocessor 152 can provide an output through display 158 and receive input from an operator through input 160. In operation, circuitry 14 is operably coupled to battery test circuitry through databus 12 and is configured to send and receive information through databus 12. An operator can instruct microprocessor 152 or microprocessor 152 can operate automatically, to retrieve data from memory 48 in battery test circuitry 10. The microprocessor 152 can process the data to calculate battery condition and follow trends in the measured values retrieved from memory 48. This information can be used to diagnose the condition of the battery 16 as well as use a charge and discharge history experienced by battery 16. Further, the information can be used to validate warranty claims in which a battery is returned to a manufacturer under a claim that it is defective.

[0020] External circuitry 14 can include additional input, output or input/output circuits 162 for communication using other techniques. For example, data can be sent to a printer or other computer system. Any type of data link can be used including modems, Ethernet or networking connections, etc.

[0021] In one embodiment, the external circuitry 14 comprises a personal data assistant (PDA) such as a Palm Pilot™. In such an embodiment, I/O 100 in battery test circuitry 10 can comprise a cradle which is adapted to receive the PDA. In such an embodiment, the PDA can simply be “dropped” into the cradle in order to exchange data with test circuitry 10. Similarly, many PDAs include an infrared or RF link which can be used to exchange data with battery test circuitry 10.

[0022] In some embodiments, battery test circuitry 10 can include circuitry configured to charge battery 16. In such embodiments, memory 48 can be used to log information regarding any charge which is applied to battery 16.

[0023] Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. For example, any type of battery test or battery test circuitry can be used by battery tester 10. Further, the databus 12 can be in accordance with any databus technique and should not be limited to the examples set forth herein. In various embodiments, battery tester 10 can be powered through power received through battery 16 or can be powered through power received through databus 12 or from a scan tool.