Systems, apparatus and methods for battery charge management

Abstract

Systems, apparatus, and methods for automobile battery management is provided. In one embodiment, an apparatus for providing balanced and individualized charging to a battery pack is provided. The apparatus uses microcontrollers to determine a charge level of the batteries, and correspondingly controls a power balancer to apply a charge current to the battery in relation to the charge level, and dissipates the remaining charge current as heat energy. In one embodiment, a system controller controls a balanced charging operation of the battery system, provides an interface for a user to monitor cell-level parameters, and protects the battery cells from undercharging or overcharging during the charging or discharging operations.

I claim the following: 
     
         1 . An apparatus for providing balanced and individualized charging to each battery cell in a plurality of battery cells, the apparatus comprising:
 a first power transistor configured to regulate a charge current applied to a first battery cell of the plurality of battery cells; and   a PID controller configured to monitor a current charge level of the first battery cell, wherein, in operation the PID controller controls the first power transistor such that:
 a specific portion of the charge current is applied to the first battery cell, wherein the specific portion is determined in response to the current charge level of the first battery cell; 
 an unused portion of the charge current that is not applied to the first battery cell appears as a balancing current in the first power transistor; and 
 the balancing current in the first power transistor is dissipated as heat energy through a heat sink associated with the first power transistor 
   
     
     
         2 . A battery management system for use in a motor vehicle, the battery management system comprising:
 a charge balancer configured to individually control a charging operation of each of a plurality of battery cells, wherein the charge balancer includes a microcontroller to monitor a charge level of each of the plurality of battery cells and to control the charging operation of a particular battery cell in response to the charge level indicated by the particular battery cell; and   a system controller configured to govern operations of the battery management system and to direct a battery power from the plurality of battery cells to a motor controller of the motor vehicle, wherein the system controller includes a balancing controller to facilitate charging operations of the charge balancer.   
     
     
         3 . The battery management system for use in the motor vehicle as recited in  claim 2 , wherein the microcontroller is a PID controller. 
     
     
         4 . The battery management system for use in the motor vehicle as recited in  claim 3 , wherein the microcontroller controls a plurality of power balancers to apply an effective charging current to each of the plurality of battery cells, wherein each of the plurality of power balancers receive a total charge current and apply the effective charging current to each of the plurality of battery cells in response to the charge level of each of the plurality of battery cells. 
     
     
         5 . The battery management system for use in the motor vehicle as recited in  claim 4 , wherein each of the plurality of power balancers regulate a balancing current in response to a portion of the total charge current that is not used as the effective charging current for each of the plurality of battery cells, and wherein each of the plurality of power balancers dissipate the balancing current as heat energy. 
     
     
         6 . The battery management system for use in the motor vehicle as recited in  claim 5 , wherein the each of the plurality of power balancers is a power transistor. 
     
     
         7 . The battery management system for use in the motor vehicle as recited in  claim 2 , further comprising:
 a current charger configured to supply a charging current to charge each of the plurality of battery cells.   
     
     
         8 . The battery management system for use in the motor vehicle as recited in  claim 7 , wherein the system controller includes a current charger controller, wherein the current charger controller turns off the current charger when one or more of the plurality of battery cells exceeds an allowable parameter level. 
     
     
         9 . The battery management system for use in the motor vehicle as recited in  claim 8 , wherein the allowable parameter level includes at least one of:
 the charge level of each of the battery cells;   an over voltage value of each of the battery cells; or   an over temperature value of each of the battery cells.   
     
     
         10 . The battery management system for use in the motor vehicle as recited in  claim 2 , wherein the balancing controller communicates with the charge balancer to monitor characteristic information of each of the plurality of battery cells, wherein the characteristic information includes at least one of voltage, current, or temperature of each of the plurality of battery cells. 
     
     
         11 . The battery management system for use in the motor vehicle as recited in  claim 10 , wherein the balancing controller uses a predictive State of Charge (SoC) to determine a charge rate of each of the plurality of battery cells. 
     
     
         12 . The battery management system for use in the motor vehicle as recited in  claim 11 , wherein the system controller includes an enabling controller to control transfer of the battery power to the motor controller, wherein the enabling controller turns off the battery power to the motor controller if any of the plurality of battery cells exceeds an allowable parameter level. 
     
     
         13 . The battery management system for use in the motor vehicle as recited in  claim 12 , wherein the allowable parameter level includes at least one of:
 the charge level of each of the battery cells,   an under voltage value of each of the battery cells, or   an over temperature value of each of the battery cells.   
     
     
         14 . The battery management system for use in the motor vehicle as recited in  claim 2 , wherein the system controller includes a throttle controller configured to reduce a throttle of the motor controller when the battery power from the plurality of battery cells is lower than a predetermined level. 
     
     
         15 . The battery management system for use in the motor vehicle as recited in  claim 2 , wherein the system controller includes a data logger, wherein the data logger maintains logs of at least one of:
 a voltage level of each of the plurality of battery cells;   a current level of each of the plurality of battery cells;   a temperature level of each of the plurality of battery cells; or   a charge rate of each of the plurality of battery cells;   
     
     
         16 . The battery management system for use in the motor vehicle as recited in  claim 2 , wherein the system controller includes a State of Charge display to indicate the charge level of each of the plurality of battery cells, wherein the State of Charge display includes at least one of:
 an output to a gas gauge of the motor vehicle;   a battery light indicator;   an LCD display;   a plurality of LED lights; or   a serial link to an external display device.   
     
     
         17 . The battery management system for use in the motor vehicle as recited in  claim 2 , wherein the system controller includes an interface to a computing device. 
     
     
         18 . The battery management system for use in the motor vehicle as recited in  claim 17 , wherein the computing device is used for at least one of:
 review log data from the data logger; or   configure parameters of the system controller.   
     
     
         19 . The battery management system for use in the motor vehicle as recited in  claim 17 , wherein the interface includes at least one of a serial interface or an Ethernet interface. 
     
     
         20 . The battery management system for use in the motor vehicle as recited in  claim 8 , wherein the current charger controller enables the plurality of power balancers to regulate each of the plurality of battery cells when a maximum needed power difference of each of the plurality of battery cell is within a limit of heat dissipation of each of the plurality of heat sinks associated with each of the plurality of battery cells.