Method and system for balancing a battery assembly

Abstract

A method for balancing a battery assembly includes selecting, from a plurality of batteries of the battery assembly in a charging state, one or more batteries based on a status of the plurality of batteries; and controlling charging of the selected one or more batteries for balancing the plurality of batteries. Battery balancing can be energy-efficient and time-efficient. The lifetime of the battery assembly can be extended.

What is claimed is: 
     
         1 . A method for balancing a battery assembly comprising:
 selecting, from a plurality of batteries of the battery assembly in a charging state, one or more batteries based on a status of the plurality of batteries; and   controlling charging of the selected one or more batteries for balancing the plurality of batteries.   
     
     
         2 . The method of  claim 1 , further comprising obtaining the status of the plurality of batteries. 
     
     
         3 . The method of  claim 1 , wherein controlling the charging of the selected one or more batteries includes prioritizing the charging of the selected one or more batteries to be in an order based on one or more respective voltages across the selected one or more batteries. 
     
     
         4 . The method of  claim 3 , wherein prioritizing the charging of the selected one or more batteries to be in the order based on the one or more respective voltages across the selected one or more batteries includes:
 charging a first battery of the selected one or more batteries prior to charging a second battery of the selected one or more batteries, in response to a voltage across the second battery being greater than a voltage across the first battery by a difference greater than a target voltage difference.   
     
     
         5 . The method of  claim 3 , wherein prioritizing the charging of the selected one or more batteries to be the order based on the one or more respective voltages across the selected one or more batteries includes:
 charging a first battery and a second battery of the selected one or more batteries simultaneously, in response to a difference between a voltage across the first battery and a voltage across the second battery being less than or equal to a target voltage difference.   
     
     
         6 . The method of  claim 1 , wherein controlling the charging of the selected one or more batteries includes prioritizing the charging of the selected one or more batteries to be in an order based on one or more respective capacities of the selected one or more batteries. 
     
     
         7 . The method of  claim 6 , wherein prioritizing the charging of the selected one or more batteries to be in an order based on the one or more respective capacities of the selected one or more batteries includes:
 charging a first battery of the selected one or more batteries prior to charging a second battery of the selected one or more batteries, in response to a capacity of the second battery being greater than a capacity of the first battery by a difference greater than a target capacity difference.   
     
     
         8 . The method of  claim 6 , wherein prioritizing the charging of the selected one or more batteries to be in an order based on the one or more respective capacities of the selected one or more batteries includes:
 charging a first battery and a second battery of the selected one or more batteries simultaneously, in response to a difference between a capacity of the first battery and a capacity of the second battery being less than or equal to a target capacity difference.   
     
     
         9 . The method of  claim 1 , wherein:
 each of the plurality of batteries includes a plurality of cells connected in parallel and/or in series; and   controlling the charging of the selected one or more batteries includes:
 selecting one or more cells of the plurality of batteries based on the status of the plurality of batteries; and 
 controlling charging of the selected one or more cells for balancing the plurality of cells. 
   
     
     
         10 . The method of  claim 9 , wherein controlling the charging of the selected one or more cells includes prioritizing the charging of the selected one or more cells to be in an order based on one or more respective voltages across the selected one or more cells. 
     
     
         11 . The method of  claim 10 , wherein prioritizing the charging of the selected one or more cells to be in an order based on the one or more respective voltages across the selected one or more cells includes:
 charging a first cell of the selected one or more cells prior to charging a second cell of the selected one or more cells in response to a voltage across the second cell being greater than a voltage across the first cell by a difference greater than a target voltage difference.   
     
     
         12 . The method of  claim 10 , wherein prioritizing the charging of the selected one or more cells to be in the order based on the one or more respective voltages across the selected one or more cells includes:
 charging a first cell and a second cell of the selected one or more cells simultaneously in response to a difference between a voltage across the first cell and a voltage across the second cell being less than or equal to a target voltage difference.   
     
     
         13 . The method of  claim 9 , wherein controlling the charging of the selected one or cells includes prioritizing the charging of the selected one or more cells to be in an order based on one or more respective capacities across the selected one or more cells. 
     
     
         14 . The method of  claim 13 , wherein prioritizing the charging of the selected one or more cells to be in the order based on the one or more respective capacities across the selected one or more cells includes:
 charging a first cell of the selected one or more cells prior to charging a second cell of the selected one or more cells in response to a capacity of the second cell being greater than a capacity of the first cell by a difference greater than a target capacity difference.   
     
     
         15 . The method of  claim 13 , wherein prioritizing the charging of the selected one or more cells to be in the order based on the one or more respective capacities across the selected one or more cells comprises:
 charging a first cell and a second cell of the selected one or more cells simultaneously in response to a difference between a capacity of the first cell and a capacity of the second cell being less than or equal to a target capacity difference.   
     
     
         16 . A system for balancing a battery assembly comprising:
 one or more processors individually or collectively configured to:
 select, from a plurality of batteries of the battery assembly in a charging state, one or more batteries based on a status of the plurality of batteries; and 
 control charging of the selected one or more batteries for balancing the plurality of batteries. 
   
     
     
         17 . The system of  claim 16 , wherein the one or more processors are further configured to prioritize the charging of the selected one or more batteries to be in an order based on one or more respective voltages across the selected one or more batteries. 
     
     
         18 . The system of  claim 16 , wherein the one or more processors are further configured to prioritize the charging of the selected one or more batteries to be in an order based on one or more respective capacities of the selected one or more batteries. 
     
     
         19 . The system of  claim 16 , wherein:
 each of the plurality of batteries includes a plurality of cells connected in parallel and/or in series,   the one or more processors are further configured to:
 select one or more cells of the plurality of batteries based on the status of the plurality of batteries; and 
 control charging of the selected one or more cells for balancing the plurality of cells. 
   
     
     
         20 . An apparatus for battery balancing, comprising:
 a battery assembly comprising a plurality of batteries, the battery assembly being in a charging state; and   a system coupled with the plurality of batteries and including one or more processors individually or collectively configured to:
 select, from the plurality of batteries of the battery assembly in the charging state, one or more batteries based on a status of the plurality of batteries; and 
 control charging of the selected one or more batteries for balancing the plurality of batteries.