System and method for recharging a battery exposed to a harsh environment

Abstract

A rechargable battery with an internal microcontroller. The microcontroller contains a memory in which data regarding the environment to which the battery is exposed are stored. These data are read by a processor integral with the charger used to charge the battery. If these data indicates the battery may have been subjected to a harsh environment for an excessive period of time, the charger performs a complete state of health evaluation of the battery.

1 . A battery charger, for recharging a rechargeable battery, said battery charging including: 
 a current source for applying a charging current to the battery;    a plurality of circuit components to which the battery is selectively connected as part of processes for performing state-of-health evaluations of the battery; and    a processor for: regulating the charging of the battery by said current source; selectively connecting the battery to said circuit components to perform the battery state-of-health evaluations; and, based on the signals output by the components, determine the battery state-of-health, said processor being configured to: 
 read from the battery data indicating if the battery has been exposed to a harsh environment;  
 if the battery data indicates the battery was not exposed to a harsh environment ( 458 ), as part of the charging process, selectively connecting the battery to circuit components so that a partial state-of-health evaluation is performed on the battery; and  
 if the battery data indicates that the battery was exposed to a harsh environment, as part of the charging process, selectively connecting the battery to circuit components so that a full state-of-health evaluation is performed on the battery, the full state-of-health evaluation including the partial state-of-health evaluation and a further state-of-health evaluation of the battery.  
   
     
     
         2 . The battery charger of  claim 1 , wherein the partial state-of-health evaluation comprises performing a voltage-at-load test on the battery by after the battery is charged, connecting the battery to at least one selected said circuit component.  
     
     
         3 . The battery charger of  claim 1 , wherein the further state-of-heath evaluation performed as part of the full state-of-health evaluation comprises the process of determining the time required to fully charge a known charge state.  
     
     
         4 . The battery charger of  claim 1 , wherein, as part of performing the further state-of-health evaluation of the battery, the processor discharges the battery prior to connecting said current source to the battery to charge the battery, where the discharging occurs by connecting the battery to at least one selected said circuit component.  
     
     
         5 . The battery charger of  claim 1 , wherein the battery data the processor reads are data indicating if the battery was exposed to a harsh environment are data indicating the battery was at a temperature above a threshold level for more than a defined time block.  
     
     
         6 . A battery, said battery including: 
 a housing;    at least one rechargeable cell disposed in said housing;    a terminal assembly attached to said housing and connected to the at least one rechargeable cell for storing charge in the cell and withdrawing current from the cell;    an environment sensor disposed in said housing that generates an environmental signal upon the occurrence of an environmental event;    a processor disposed in said housing that receives the environmental signal and that includes a memory, the processor configured to store in the memory data representative of environmental event as measured by said environmental sensor, where the processor is connected to the at least one rechargeable cell for energization by said cell and is configured so as to have: a normal operating mode during which the processor draws a first current from the battery; and a first power down mode when the processor draws a second current from the battery, the second current being less than the first current; wherein said processor is further configured so that when said processor is in the first power down mode, the processor monitors the environment signal and, if the environmental signal indicates the occurrence of an environment event, said processor transitions from the first power down mode to the normal mode.    
     
     
         7 . The battery of  claim 6 , wherein, when said processor is in the normal, said processor writes into said data memory data indicating the occurrence of the environmental event.  
     
     
         8 . The battery of  claim 6 , wherein: 
 said environmental sensor is a temperature sensor that generates a temperature signal as a function of battery temperature: and    said processor monitors the temperature signal and, if the temperature signal indicates that the battery temperature is above a threshold level, said processor transitions from the first power down mode to the normal mode.    
     
     
         9 . The battery of  claim 6 , wherein: 
 said environmental sensor is a temperature sensor that generates a temperature signal as a function of battery temperature: and    said processor monitors the temperature signal and, if the temperature signal indicates that the battery temperature is above a threshold level, said processor transitions from the first power down mode to the normal mode and, while in the normal mode, writes into said memory data indicating the amount of time the battery temperature is above the threshold level.    
     
     
         10 . The battery of  claim 6 , wherein =p 1  said processor has a second power down mode during which said processor draws a third current from the at least one cell, the third current being greater than the second current and less than the third current; and 
 as part of the processor transition from the first power down mode to the normal power down mode, said processor transitions from the first power down mode to the second power down mode and then to the normal mode.    
     
     
         11 . A powered surgical tool system, said system including: 
 a powered surgical tool, said tool including: a power generating unit; a surgical attachment for performing a surgical/medical procedure that is actuated by said power generating unit; a control circuit for regulating actuation of the power generating unit that is configured to generate data regarding the operation of the tool and write data to a memory external to said tool;    a battery that is removably attachable to said powered surgical tool, the battery having: at least one rechargeable cell for energizing said tool power generating unit; and a memory that, upon attachment of said battery tool is capable of storing data written thereto by said tool control circuit; and    a static unit separate from said is provided for removably receiving the battery, the static unit having a device ( 298 ) for reading from the data in the battery memory, including the data stored regarding operation of the power tool.    
     
     
         12 . The powered surgical tool system of  claim 11 , further including a charger ( 42 ) for removably receiving the battery, the charger including a current source ( 290 ) for applying a charging current to the at least one rechargeable cell, and said charger includes said device ( 298 ) for reading the data in the battery memory.  
     
     
         13 . The powered surgical tool system of  claim 11 , wherein the static unit is connected to a communications bus ( 586 ) by a data transceiver head is configured to output over the communications bus the data read from data stored regarding operation of the power tool.  
     
     
         14 . The powered surgical tool system of  claim 11 , wherein said tool power generating unit is a motor.