Uninterruptible power supply system having an NiMH or Li-ion battery

Abstract

An uniterruptible power supply (UPS) system that includes one or more NiMH or Li-ion batteries is provided. In one general aspect, the invention features a power supply system including a power input to receive input power from a power source, a power output to provide output power to a load, at least one NiMH or Li-ion battery having a battery output that provides battery power, at least one power module coupled to the power input to receive the input power, coupled to the battery output to receive the battery power and coupled to the power output to provide the output power, a controller, coupled to the at least one power module, constructed and arranged to monitor and control the output power from the at least one power module. A UPS system using a NiMH or Li-ion battery typically uses less space and weigh less than a UPS having a lead acid battery. Additionally, NiMH and Li-ion batteries perform better at temperature extremes than do comparable lead acid batteries.

What is claimed is:  
     
         1 . A power supply system comprising: 
 a power input to receive input power from a power source;    a power output to provide output power to a load;    at least one battery having a battery output that provides battery power, the at least one battery being selected from the group consisting of: nickel metal hydride and lithium ion polymer;    at least one power module coupled to the power input to receive the input power, coupled to each battery output to receive a power of each battery and coupled to the power output to provide the output power; and    a controller, coupled to the at least one power module, constructed and arranged to monitor and control the output power from the at least one power module.    
     
     
         2 . The power supply system according to  claim 1 , wherein the at least one battery is a nickel metal hydride battery.  
     
     
         3 . The power supply system according to  claim 1 , wherein the at least one battery is a lithium ion battery.  
     
     
         4 . The power supply system according to  claim 2 , further comprising means for measuring a current of the battery, wherein the controller has program code means embodied therein for determining a state of charge of at least one battery by monitoring the current of at least one battery.  
     
     
         5 . The power supply system according to  claim 3 , further comprising means for measuring a current of the battery, wherein the controller has program code means embodied therein for determining a state of charge of the battery by monitoring the current of the battery.  
     
     
         6 . The power supply system according to  claim 2 , further comprising means for measuring a current, a voltage and a temperature of at least one of the nickel metal hydride batteries, wherein the controller has program code means embodied therein for completing the method of charging the at least one nickel metal hydride battery, the method comprising: 
 determining a state of charge of the battery by monitoring the current of the battery;    for between about 0% to about 99% of a charging capacity each battery, charging each battery at a constant current rate of between about 0.3C to about 1C;    stopping the charge of each battery if the temperature of each battery starts to rise substantially;    stopping the charge if a temperature of each battery rises above about 40° C. or about 20° C. above an ambient temperature; and    applying a trickle current to each battery such that a slight temperature differential is achieved between each battery case and the ambient temperature.    
     
     
         7 . A power supply system comprising: 
 a filter to receive and filter input power from a power source;    a rectifier coupled to the filter    at least one battery having a battery output that provides battery power, the at least one battery being selected from the group consisting of: nickel metal hydride and lithium ion polymer;    at least one control switch coupled to the rectifier to receive the input power, coupled to each battery output to receive a power of each battery and coupled to an input to provide the output power; and    a controller, coupled to the at least one control switch, constructed and arranged to monitor and control the output power from the at least one control switch.    
     
     
         8 . The power supply system according to  claim 7 , further comprising an inverter coupled between the at least one control switch and the transformer, wherein the inverter is coupled to the controller.  
     
     
         9 . The power supply system according to  claim 7 , wherein the at least one battery is a nickel metal hydride battery.  
     
     
         10 . The power supply system according to  claim 7 , wherein the at least one battery is a lithium ion battery.  
     
     
         11 . The power supply system according to  claim 9 , further comprising means for measuring a current of the battery, wherein the controller has program code means embodied therein for determining a state of charge of the battery by monitoring the current of the battery.  
     
     
         12 . The power supply according to  claim 11 , wherein the means for measuring a current of the battery comprises a current shunt.  
     
     
         13 . The power supply system according to  claim 10 , further comprising means for measuring a current of the battery, wherein the controller has program code means embodied therein for determining a remaining run time of the battery by monitoring the current of the battery.  
     
     
         14 . The power supply according to  claim 13 , wherein the means for measuring a current of the battery comprises a current shunt.  
     
     
         15 . The power supply system according to  claim 7 , wherein the rectifier is coupled to the controller.  
     
     
         16 . The power supply system according to  claim 7 , further comprising a transformer coupled between the battery and the output.  
     
     
         17 . A power supply system comprising: 
 a power input to receive input power from a power source;    a power output to provide output power to a load;    at least one battery having a battery output that provides battery power, the at least one battery being selected from the group consisting of: nickel metal hydride and lithium ion polymer;    at least one power module coupled to the power input to receive the input power, coupled to each battery output to receive a power of each battery and coupled to the power output to provide the output power;    means for measuring a current of at least one the batteries; and    a controller, coupled to the at least one power module, constructed and arranged to monitor and control the output power from the at least one power module, the controller having program code means embodied therein for completing a method of charging the at least one Nickel Metal Hydride battery, the method comprising:    for between about 0% to about 99% of a charging capacity each battery, charging each battery at a constant current rate of between about 0.5C to about 1C;    stopping the charge of each battery if the temperature of each battery starts to rise substantially;    stopping the charge if a temperature of each battery rises above about 40° C. or about 20° C. over an ambient temperature; and    applying a trickle current to each battery such that a slight temperature differential is achieved between each battery case and the ambient temperature.    
     
     
         18 . A method of charging at least one Nickel Metal Hydride battery in an uninterruptible power supply system having at least one power module coupled to a power input to receive input power, coupled to each battery output to receive power from each battery and coupled to a power output to provide output power to a load, and a controller, coupled to the at least one power module, constructed and arranged to monitor and control the output power from the at least one power module, the method comprising: 
 measuring a current of each battery;    for between about 0% to about 99% of a charging capacity each battery, applying a current to each battery to charge each battery at a constant current rate of between about 0.5C to about 1C;    stopping the applied current of each battery if the temperature of each battery starts to rise substantially;    stopping the applied current if a temperature of each battery rises above about 40° C. or above 20° C. over an ambient temperature; and    applying a trickle current to each battery such that a slight temperature differential is achieved between each battery case and the ambient temperature.