Battery monitor for electric vehicles

Claim 2

A battery monitor for monitoring a plurality of batteries, said battery monitor comprising: means for providing battery voltage signals indicative of the battery voltage of each of the plurality of batteries; a single multiplexing device having a predetermined number of channels, said multiplexing device being responsive to the battery voltage signals from the plurality of batteries through the means for providing battery voltage signals, said multiplexing device outputting a selected one of the battery voltage signals; isolator means for receiving the selected battery voltage signal and transferring the selected battery voltage signal to a portion of the battery monitor isolated from the battery voltage signals from each of the plurality of batteries; controller means for receiving the selected battery voltage signal, said controller means providing a signal indicative of the voltage of the selected battery voltage signal; and switching means for allowing the controller means to determine the battery voltage of the selected battery voltage signal when current from the plurality of batteries is flowing in the battery monitor and when current from the plurality of batteries is interrupted, said switching means including at least one switched filter that is selectively switched into and out of the battery monitor by the controller means through the isolator means prior to the battery voltage signals being applied to the multiplexing device, said at least one switched filter allowing the controller means to provide an instantaneous battery voltage measurement when the switched filter is switched out of the battery monitor, and a filtered battery voltage measurement when the switched filter is switched into the battery monitor.

Claim 3

The battery monitor according to claim 1 further comprising temperature measuring means for determining the temperature of at least some of the plurality of batteries, said temperature measuring means transmitting a battery temperature signal to the multiplexing device, said multiplexing device selecting a battery temperature signal to be transferred to the controller means.

Claim 4

The battery monitor according to claim 2 wherein the temperature measuring means for determining the battery temperature includes a thermistor.

Claim 5

The battery monitor according to claim 1 wherein the isolator means is a plurality of opto-isolators, wherein an opto-isolator is provided for each battery being monitored, and wherein a particular opto-isolator charges a capacitor when the particular opto-isolator is selected to determine a particular battery voltage.

Claim 6

The battery monitor according to claim 1 wherein the isolator means is an opto-isolator, said opto-isolator isolating the battery voltage of each of the plurality of batteries from the controller means.

Claim 7

The battery monitor according to claim 1 wherein the multiplexing device is responsive to the controller means to determine which of the battery voltage signals will be the selected battery voltage signal from the multiplexing device.

Claim 8

The battery monitor according to claim 1 wherein the battery monitor monitors the batteries associated with an electric vehicle, said battery monitor being positioned proximate to a battery tub that holds the plurality of batteries.

Claim 9

The battery monitor according to claim 1 wherein the means for providing a battery voltage signal includes a resistor divider network.

Claim 10

A battery monitor for monitoring a plurality of batteries, said battery monitor comprising: means for providing battery voltage signals indicative of the battery voltage of each of the plurality of batteries; selecting means for selecting one of the battery voltage signals from the plurality of batteries; isolator means for receiving the selected battery voltage signal and transferring the selected battery voltage signal to a portion of the battery monitor isolated from the battery voltage signals from each of the plurality of batteries; controller means for receiving the selected battery voltage signal from the selecting means through the isolator means, said controller means providing a signal indicative of the voltage of the selected battery voltage signal; and switching means for allowing the controller means to determine the battery voltage of the selected battery voltage signal when current from the plurality of batteries is flowing in the battery monitor and when current from the plurality of batteries is interrupted, said switching means including at least one switched filter that is selectively switched into and out of the battery monitor by the controller means through the isolator means, said at least one switched filter allowing the controller means to provide an instantaneous battery voltage measurement when the switched filter is switched out of the battery monitor, and a filtered battery voltage measurement when the switched filter is switched into the battery monitor.

Claim 11

A battery monitor for monitoring a plurality of batteries, said battery monitor comprising: means for providing battery voltage signals indicative of the battery voltage of each of the plurality of batteries; selecting means for selecting one of the battery voltage signals from the plurality of batteries; isolator means for receiving the selected battery voltage signal and transferring the selected battery voltage signal to a portion of the battery monitor isolated from the battery voltage signals from each of the plurality of batteries; controller means for receiving the selected battery voltage signal from the selecting means through the isolator means, said controller means providing a signal indicative of the voltage of the selected battery voltage signal; and switching means for allowing the controller means to determine the battery voltage of the selected battery voltage signal when current from the plurality of batteries is flowing in the battery monitor and when current from the plurality of batteries is interrupted, said switching means including at least one switched filter that is selectively switched into and out of the battery monitor by the controller means through the isolator means, said at least one switched filter allowing the controller means to provide an instantaneous battery voltage measurement when the switched filter is switched out of the battery monitor, and a filtered battery voltage measurement when the switched filter is switched into the battery monitor.

Claim 12

The battery monitor according to claim 9 wherein the at least one switched filter is a plurality of switched filters where one switched filter is provided for each battery, said switched filters filtering the battery voltage signals before the battery voltage signals are applied to the selecting means.

Claim 13

The battery monitor according to claim 9 further comprising temperature measurement means for determining the temperature of at least some of the plurality of batteries, said temperature measurement means transmitting battery temperature signals to the selecting means, said selecting means selecting a battery temperature signal to be transferred to the controller means.

Claim 14

The battery monitor according to claim 9 wherein the selecting means is a single multiplexing device having a predetermined number of channels, said multiplexing device being responsive to the battery voltage signals from the plurality of batteries, said multiplexing device outputting a selected one of the battery voltage signals.

Claim 15

The battery monitor according to claim 9 wherein the isolator means is an opto-isolator, said opto-isolator isolating the battery voltage of each of the plurality of batteries from the controller means.

Claim 16

The battery monitor according to claim 9 wherein the selecting means is responsive to the controller means to determine which of the battery voltage signals will be the selected battery voltage signal from the selecting means.

Claim 17

The battery monitor according to claim 9 wherein the battery monitor monitors the batteries associated with an electric vehicle, said battery monitor being positioned proximate to a battery tub that holds the plurality of batteries in the vehicle.

Claim 18

A battery monitor for monitoring a plurality of batteries of an electric vehicle, said battery monitor comprising: means for providing a battery voltage signal indicative of the battery voltage of each of the plurality of batteries; a single multiplexing device having a predetermined number of channels, said multiplexing device being responsive to the battery voltage signals from the plurality of batteries through the means for providing a battery voltage signal, said multiplexing device outputting a selected one of the battery voltage signals; temperature measuring means for determining the temperature of at least some of the plurality of batteries, said temperature measuring means transmitting a battery temperature signal to the multiplexing device, said multiplexing device outputting a selected one of the battery temperature signals; controller means for receiving the selected battery voltage signal and the selected battery temperature signal, said controller means determining the battery voltage of the selected one of the battery voltage signals and the battery temperature of the selected one of the battery temperature signals; isolator means for separating the battery monitor into a high voltage side and a low voltage side, said plurality of batteries being on the high voltage side and said controller means being on the low voltage side, wherein the selected battery voltage signal and the selected battery temperature signal from the multiplexing device are applied to the controller means through the isolator means and signals from the controller means to the multiplexing device for selecting one of the battery voltage signals and the battery temperature signals are applied through the isolator means; and switching means for allowing the controller means to determine the battery voltage of the selected voltage signal when current from the plurality of batteries is flowing in the battery monitor and current from the batteries is interrupted, wherein the switching means includes at least one switched filter that is selectively switched into and out of the battery monitor by the controller means through the isolator means, said at least one switched filter allowing the controller means to provide an instantaneous battery voltage measurement when the switched filter is switched out of the battery monitor, and a filtered battery voltage measurement when the switched filter is switched into the battery monitor.

Claim 19

A battery monitor for monitoring a plurality of batteries of an electric vehicle, said battery monitor comprising: means for providing a battery voltage signal indicative of the battery voltage of each of the plurality of batteries; a single multiplexing device having a predetermined number of channels, said multiplexing device being responsive to the battery voltage signals from the plurality of batteries through the means for providing a battery voltage signal, said multiplexing device outputting a selected one of the battery voltage signals; temperature measuring means for determining the temperature of at least some of the plurality of batteries, said temperature measuring means transmitting a battery temperature signal to the multiplexing device, said multiplexing device outputting a selected one of the battery temperature signals; controller means for receiving the selected battery voltage signal and the selected battery temperature signal, said controller means determining the battery voltage of the selected one of the battery voltage signals and the battery temperature of the selected one of the battery temperature signals; isolator means for separating the battery monitor into a high voltage side and a low voltage side, said plurality of batteries being on the high voltage side and said controller means being on the low voltage side, wherein the selected battery voltage signal and the selected battery temperature signal from the multiplexing device are applied to the controller means through the isolator means and signals from the controller means to the multiplexing device for selecting one of the battery voltage signals and the battery temperature signals are applied through the isolator means; and switching means for allowing the controller means to determine the battery voltage of the selected voltage signal when current from the plurality of batteries is flowing in the battery monitor and current from the batteries is interrupted, wherein the switching means includes at least one switched filter that is selectively switched into and out of the battery monitor by the controller means through the isolator means, said at least one switched filter allowing the controller means to provide an instantaneous battery voltage measurement when the switched filter is switched out of the battery monitor, and a filtered battery voltage measurement when the switched filter is switched into the battery monitor.

Claim 20

The battery monitor according to claim 16 wherein the at least one switched filter is a plurality of switched filters where one switched filter is provided for each battery, said switched filters filtering the battery voltage signals before the battery voltage signals are applied to the multiplexing device.