Washers for a lithium ion battery cell terminal

Abstract

The present disclosure relates to washers for lithium ion battery cell terminals. A lithium ion battery module includes a housing, a first battery cell disposed in the housing and having a cell terminal protruding from a surface of a casing of the first battery cell, where the cell terminal is configured to enable electrical connection to the battery cell, and a washer stack disposed about the cell terminal. The washer stack has an electrically insulative washer and an electrically conductive washer. The electrically conductive washer is disposed adjacent to the electrically insulative washer such that the electrically insulative washer is positioned between the electrically conductive washer and the surface of the casing, and the electrically conductive washer is configured to enable electrical connection to the cell terminal.

1 . A lithium ion battery module, comprising:
 a housing;   a first battery cell disposed in the housing and having a cell terminal protruding from a surface of a casing of the first battery cell, wherein the cell terminal is configured to enable electrical connection to the battery cell; and   a washer stack disposed about the cell terminal, comprising an electrically insulative washer and an electrically conductive washer; and   wherein the electrically conductive washer is disposed adjacent to the electrically insulative washer such that the electrically insulative washer is positioned between the electrically conductive washer and the surface of the casing, and wherein the electrically conductive washer is configured to enable electrical connection to the cell terminal.   
     
     
         2 . The lithium ion battery module of  claim 1  wherein the electrically conductive washer is welded to a bus bar such that the bus bar is electrically connected to the cell terminal, and wherein a physical connection between the bus bar and the cell terminal is absent. 
     
     
         3 . The lithium ion battery module of  claim 1 , wherein the electrically conductive washer has a top surface and a bottom surface, and wherein the bottom surface is adjacent to the electrically insulative washer and the top surface is adjacent to a bus bar. 
     
     
         4 . The lithium ion battery module of  claim 3 , wherein the top surface is substantially aligned with the cell terminal. 
     
     
         5 . The lithium ion battery module of  claim 3 , wherein the cell terminal protrudes beyond the top surface. 
     
     
         6 . The lithium ion battery module of  claim 3 , wherein an upper surface of the cell terminal is positioned between the top surface and the bottom surface. 
     
     
         7 . The lithium ion battery module of  claim 1 , wherein a washer of the washer stack comprises a cross section with a length that is oriented substantially parallel to the surface of the casing. 
     
     
         8 . The lithium ion battery module of  claim 1 , wherein a washer of the washer stack comprises a protrusion extending away from the surface of the casing. 
     
     
         9 . The lithium ion battery module of  claim 1 , wherein a washer of the washer stack comprises a protrusion extending toward the surface of the casing. 
     
     
         10 . The lithium ion battery module of  claim 1 , wherein one or both of the electrically insulative washer and the electrically conductive washer comprise a round shape, a square shape, a polygonal shape, or any combination thereof. 
     
     
         11 . The lithium ion battery module of  claim 1 , wherein the electrically insulative washer comprises a polymeric material 
     
     
         12 . The lithium ion battery module of  claim 11 , wherein the polymeric material comprises a Shore D hardness of greater than 50. 
     
     
         13 . The lithium ion battery module of  claim 11 , wherein the polymeric material comprises a Shore A hardness of greater than 70. 
     
     
         14 . The lithium ion battery module of  claim 1 , wherein the electrically conductive washer comprises copper. 
     
     
         15 . The lithium ion battery module of  claim 1 , wherein the electrically conductive washer comprises aluminum. 
     
     
         16 . The lithium ion battery module of  claim 1 , wherein the electrically insulative washer is disposed adjacent to the surface of the casing. 
     
     
         17 . A lithium ion battery module, comprising:
 a housing;   a battery cell disposed in the housing and having a cell terminal protruding from a surface of a casing of the first battery cell, wherein the cell terminal is configured to enable electrical connection to the battery cell;   a washer stack disposed about the cell terminal, comprising an electrically insulative washer and an electrically conductive washer;   wherein the electrically insulative washer is disposed adjacent to the surface of the casing;   wherein the electrically conductive washer is disposed in the washer stack such that the electrically insulative washer is positioned between the electrically conductive washer and the surface of the casing; and   a bus bar electrically coupled to the cell terminal via the electrically conductive washer.   
     
     
         18 . The lithium ion battery module of  claim 17 , wherein the electrically conductive washer is welded to the bus bar such that the bus bar is electrically connected to the cell terminal, and wherein a physical connection between the bus bar and the cell terminal is absent. 
     
     
         19 . The lithium ion battery module of  claim 17 , comprising an additional electrically insulative washer positioned in the stack between the electrically insulative washer and the electrically conductive washer, wherein the electrically insulative washer and the additional electrically insulative washer each comprise a polymeric material. 
     
     
         20 . The lithium ion battery module of  claim 19 , wherein the additional electrically insulative washer comprises a recess configured to receive at least a portion of the electrically conductive washer. 
     
     
         21 . A battery module, comprising:
 a housing;   a battery module terminal configured to provide an electrical output of the battery module when coupled to an electrical load;   a battery cell disposed in the housing and having a cell terminal protruding from a surface of a casing of the first battery cell, wherein the cell terminal is configured to enable electrical connection to the first battery cell;   a washer stack disposed about the cell terminal, comprising a stack of electrically insulative washers disposed adjacent to the surface of the casing and an electrically conductive washer disposed adjacent to the stack of electrically insulative washers such that the stack of electrically insulative washers are positioned between the electrically conductive washer and the surface of the casing; and   a bus bar electrically coupled to the electrically conductive washer, wherein the bus bar is configured to establish an electrical connection between the battery cell and the battery module terminal.   
     
     
         22 . The battery module of  claim 21 , wherein the electrically conductive washer is welded to the bus bar such that the bus bar is electrically connected to the cell terminal, and wherein a physical connection between the bus bar and the cell terminal is absent. 
     
     
         23 . The battery module of  claim 21 , wherein the stack of electrically insulative washers comprises electrically insulative ceramic material, electrically insulative polymeric material, electrically insulative composite material, or any combination thereof. 
     
     
         24 . The battery module of  claim 21 , wherein the electrically conductive washer comprises copper or aluminum. 
     
     
         25 . The battery module of  claim 21 , wherein the bus bar is welded to the electrically conductive washer.