Arrangements for inhibiting intrusion into battery pack electrical components

Abstract

A battery pack and a method of assembling a battery pack. The battery pack may include an outer housing; a cell module supportable by the outer housing, the cell module including a module housing, a plurality of battery cells supported by the module housing, the battery cells having an energy of at least about 60 Watt-hours, a controller operable to control an operation of the battery pack, a conductive strap electrically connected to at least one of the battery cells, a weld strap connected between the controller and the conductive strap, and a terminal electrically connected to the battery cells and operable to connect the battery cells to an electrical device for power transfer; and a vapor-deposited, hydrophobic nano coating applied to at least a portion of the cell module.

What is claimed is: 
     
         1 . A power supply device comprising:
 a cell module including
 a module housing, 
 a plurality of battery cells supported by the module housing, 
 a controller operable to control an operation of the power supply device, 
 a conductive strap electrically connected to at least one of the plurality of battery cells, and 
 a connector electrically connected to the conductive strap and configured to transfer power from the plurality of battery cells to an electrical device; and 
   a vapor-deposited coating applied to at least a portion of the cell module.   
     
     
         2 . The power supply device of  claim 1 , wherein the vapor-deposited coating is applied to substantially all of the cell module. 
     
     
         3 . The power supply device of  claim 1 , wherein the vapor-deposited coating includes a poly(p-xylylene) polymer. 
     
     
         4 . The power supply device of  claim 1 , wherein the vapor-deposited coating has a thickness of less than about 25 microns (μm). 
     
     
         5 . The power supply device of  claim 4 , wherein the vapor-deposited coating has a thickness of between about 1 μm and about 10 μm. 
     
     
         6 . The power supply device of  claim 1 , wherein the controller includes a substrate, an electronic component supported on the substrate, and a base coating applied to at least the electronic component, and wherein the vapor-deposited coating is applied over the base coating. 
     
     
         7 . The power supply device of  claim 1 , wherein the vapor-deposited coating has a dielectric breakdown strength between 200 Volts/micron (V/μm) and 300 V/μm. 
     
     
         8 . The power supply device of  claim 1 , wherein the vapor-deposited coating is applied to at least a portion of the plurality of battery cells, and wherein the plurality of battery cells are operable to supply discharge current to the electrical device to an operating temperature of about 50° C. and about 110° C. 
     
     
         9 . The power supply device of  claim 1 , wherein the vapor-deposited coating provides a corrosive resistance to a coated component of less than 10% swelling when exposed to an inorganic reagent or an organic solvent. 
     
     
         10 . The power supply device of  claim 1 , wherein the plurality of battery cells have a capacity, and wherein the vapor-deposited coating is applied to an at least partially charged battery cell of the plurality of battery cells. 
     
     
         11 . The power supply device of  claim 1 , wherein the power supply device is operable to supply discharge current to at least one of a power tool and an outdoor tool, the at least one of the power tool and the outdoor tool including a hand-held tool, the hand-held tool being supportable by a user during operation. 
     
     
         12 . The power supply device of  claim 1 , further comprising a plurality of cell modules. 
     
     
         13 . A power supply device comprising:
 a housing;   a battery cell supported by the housing and including a cell header, the battery cell having a nominal voltage of between about 3.4 V and about 4.2 V, the battery cell having a capacity of more than about 2 Ah; and   a vapor-deposited coating applied to at least a portion of the battery cell.   
     
     
         14 . The power supply device of  claim 13 , further comprising a conductive strap electrically connectable to the cell header, wherein the vapor-deposited coating is applied to at least a portion of the conductive strap. 
     
     
         15 . The power supply device of  claim 13 , further comprising a seal member sealing an interface of the cell header, wherein the vapor-deposited coating is applied to the seal member. 
     
     
         16 . The power supply device of  claim 15 , further comprising a conductive strap electrically connectable to the cell header and operable to hold the seal member in a position, wherein the conductive strap is welded to the cell header. 
     
     
         17 . The power supply device of  claim 13 , wherein the housing is an outer housing; and
 wherein the power supply device further includes a cell module mountable relative to the housing, the cell module including   a module housing,   the battery cell, the battery cell being supported by the module housing,   a controller operable to control an operation of the power supply device,   a conductive strap electrically connected the battery cell,   a weld strap connected between the controller and the conductive strap, and   a terminal electrically connected to the battery cell and operable to connect the battery cell to an electrical device for power transfer,   wherein the vapor-deposited coating is applied to at least a portion of the cell module.   
     
     
         18 . The power supply device of  claim 17 , wherein the vapor-deposited coating is applied to substantially all of the cell module. 
     
     
         19 . The power supply device of  claim 13 , wherein the vapor-deposited coating includes a poly(p-xylylene) polymer. 
     
     
         20 . The power supply device of  claim 13 , wherein the battery cell has a capacity of less than about 5 Ah.