System and method for maximizing battery life

Abstract

A fail safe battery pack is disclosed and claimed wherein first and second housings are affixed together. A plurality of battery cells reside within and fixedly engage the first and the second housings. First and second printed circuit boards (PCBs) reside within first and second lattice structures of the first and second housings. A variable bias device resides in the first and/or second lattice structure of the first and second housing and engages the first and/or second PCBs. When the bias of the variable bias device is sufficiently large it overcomes a plurality of fixed mechanically biased devices operating between the PCB and the plurality of battery cells and tending to separate same and causes the PCB to electrically communicate with the plurality of battery cells. When the bias of the variable bias device is sufficiently small, the plurality of fixed mechanically biased devices separates the PCB and the plurality of battery cells rendering the battery cells in an electrically safe condition.

1 - 20 . (canceled) 
     
     
         21 . A method for maximizing battery pack life in a battery power system having a battery enclosure with a plurality of battery packs installed in respective battery compartments and having a plurality of replacement battery packs comprising the steps of:
 measuring, using a microcontroller, the absolute temperature of each battery pack of said plurality of battery packs installed in respective battery compartments;   adding, using a microcontroller, for each said battery pack respectively of said plurality of battery packs installed in respective battery compartments, said absolute temperature measurement to a running sum of absolute temperature measurements stored in memory on said each respective installed battery pack and to a running sum of absolute temperature measurements stored in memory on said battery enclosure for said respective battery compartment;   incrementing, using a microcontroller, for each said battery pack respectively of said plurality of battery packs installed in respective battery compartments, a running total of the number of absolute temperature measurements stored in memory on said each respective installed battery pack and a running total of the number of absolute temperature measurements stored in memory on said battery enclosure for said respective battery compartment;   repeating said steps of measuring, adding, and incrementing at equal time intervals on an on-going basis;   removing an installed battery pack from a battery compartment creating an unoccupied battery compartment;   repeating said step of removing until all battery compartments are unoccupied;   computing, using a microcontroller, for each unoccupied battery compartment respectively, a battery compartment temperature history value equal to said stored running sum of absolute temperature measurements for said unoccupied battery compartment divided by said stored running total of the number of absolute temperature measurements for said unoccupied battery compartment;   selecting, using a microcontroller, from all unoccupied battery compartments, the unoccupied battery compartment having the highest battery compartment temperature history value;   computing, using a microcontroller, for each replacement battery pack of said plurality of replacement battery packs respectively, a battery pack temperature history value equal to said stored running sum of absolute temperature measurements for said replacement battery pack divided by said stored running total of the number of absolute temperature measurements for said replacement battery pack;   selecting, using a microcontroller, from said plurality of replacement battery packs, the replacement battery pack having the lowest battery pack temperature history value;   installing said replacement battery pack having said lowest battery pack temperature history value into said unoccupied battery compartment having said highest battery compartment temperature history value, and   repeating said steps of computing, selecting, computing, selecting, and installing for each unoccupied battery compartment.   
     
     
         22 . A method for maximizing battery pack life in a battery power system as claimed in  claim 21  further comprising the steps of:
 incrementing, using a microcontroller, at the time of said removing an installed battery pack from a battery compartment, a cycle count stored in memory on said battery pack being removed; 
 comparing, using a microcontroller, said cycle count stored in memory on said battery pack being removed to a count threshold, and 
 selecting for maintenance said battery pack being removed, if said battery pack cycle count exceeds said count threshold. 
 
     
     
         23 . A method for maximizing battery pack life in a battery power system as claimed in  claim 21  further comprising the steps of:
 incrementing, using a microcontroller, at the time of said removing an installed battery pack from a battery compartment, a cycle count stored in memory on said battery enclosure for said battery compartment from which said battery pack is being removed; 
 comparing, using a microcontroller, said cycle count stored in memory on said battery enclosure for said battery compartment from which said battery pack is being removed to a count threshold, and 
 selecting for maintenance said battery compartment from which said battery pack is being removed if said compartment cycle count exceeds said count threshold. 
 
     
     
         24 . A method for maximizing battery pack life in a battery power system as claimed in  claim 21  further comprising the steps of:
 calculating, using a microcontroller, at the time of said removing an installed battery pack from a battery compartment, an accrued time-of-use equal to said stored running total of the number of absolute temperature measurements for said battery pack being removed multiplied by said equal time interval; 
 comparing, using a microcontroller, said time-of-use calculated for said battery pack being removed to a time threshold, and 
 selecting for maintenance said battery pack being removed if said battery pack time-of-use exceeds said time threshold. 
 
     
     
         25 . A method for maximizing battery pack life in a battery power system as claimed in  claim 21  further comprising the steps of:
 calculating, using a microcontroller, at the time of said removing an installed battery pack from a battery compartment, an accrued time-of-use equal to said stored running total of the number of absolute temperature measurements for said battery compartment multiplied by said equal time interval; 
 comparing, using a microcontroller, said time-of-use calculated for said battery compartment to a time threshold, and 
 selecting for maintenance said battery compartment if said battery compartment time-of-use exceeds said time threshold. 
 
     
     
         26 . A method for managing battery pack utilization in a battery power system having a battery enclosure with a plurality of battery packs installed in respective battery compartments comprising the steps of:
 measuring, using a microcontroller, the electrical current of each battery pack of said plurality of battery packs installed in respective battery compartments;   calculating, using a microcontroller, for said each battery pack, an electrical charge by multiplying the electrical current of said each battery pack of said plurality of battery packs installed in respective battery compartments by a time interval;   adding, using a microcontroller, for each said battery pack, said electrical charge to a cycle-discharge value when said electrical charge is negative or otherwise to a cycle-charge value when said electrical charge is zero or positive;   adding, using a microcontroller, for each said battery pack, said electrical charge to a life-discharge value when said electrical charge is negative otherwise to a life-charge value when said electrical charge is zero or positive, both said life values stored in memory on each said battery pack respectively;   computing, using a microcontroller, for each said battery pack a net-cycle-charge value by adding said cycle-discharge value to said cycle-charge value;   comparing, using a microcontroller, for each said battery pack said net-cycle-charge value to a (negative) discharge threshold;   removing said each battery pack from said battery compartment if said net-cycle-charge value is less than said discharge threshold, and   repeating on said time interval said steps of measuring, calculating, adding, adding, computing, comparing, and removing on an on-going basis.   
     
     
         27 . A method for managing battery pack utilization in a battery power system as claimed in  claim 26  further comprising the steps of:
 comparing, using a microcontroller, for said each battery pack said life-charge value to a threshold, and 
 selecting for maintenance said each battery pack if removed and if said life-charge value is greater than said threshold. 
 
     
     
         28 . A method for managing battery pack utilization in a battery power system as claimed in  claim 26  further comprising the steps of:
 comparing, using a microcontroller, for said each battery pack said life-discharge value to a threshold, and 
 selecting for maintenance said each battery pack if removed and if said life-discharge value is less than said threshold. 
 
     
     
         29 . A method for managing battery pack utilization in a battery power system as claimed in  claim 26  further comprising the steps of:
 computing, using a microcontroller, for said each battery pack, a life-charge-throughput value equal to the sum of said life-charge value and the absolute value of said life-discharge value respectively; 
 comparing, using a microcontroller, for said each battery pack said life-charge-throughput value to a threshold, and 
 selecting for maintenance said each battery pack if removed and if said life-charge-throughput value is greater than said threshold.