Battery cell with integrated vapor chamber

Abstract

A battery cell is made more thermally efficient with the addition of an integrated vapor chamber that extends out from the cell and into an external heat exchange interface. The integrated vapor chamber can contain a working fluid which undergoes phase changes between liquid and vapor phases when there is a temperature differential between the interior and exterior of the cell. The integrated vapor chamber can include a wicking material to transfer the working fluid to the exterior wall of the vapor chamber. The integrated vapor chamber allows for both heating and cooling of the battery cell.

What is claimed is: 
     
         1 . A battery cell comprising:
 a cell body including a spiral wound electrode; and   a vapor chamber at least partially embedded within the spiral wound electrode of the cell body.   
     
     
         2 . The battery cell of  claim 1 , wherein the vapor chamber is configured to transfer heat between the interior of the cell body and a region external to the cell body. 
     
     
         3 . The battery cell of  claim 1 , further comprising a stem extending from the battery cell comprising a portion of the vapor chamber. 
     
     
         4 . The battery cell of  claim 1 , further comprising a wicking structure within the vapor chamber. 
     
     
         5 . The battery cell of  claim 4 , wherein the wicking structure comprises at least one of a wick or a wicking material. 
     
     
         6 . The battery cell of  claim 4 , wherein the wicking structure extends an entire length of the vapor chamber. 
     
     
         7 . The battery cell of  claim 4 , wherein the wicking structure includes at least one vapor channel. 
     
     
         8 . The battery cell of  claim 7 , wherein the wicking structure has a ring-shaped cross section. 
     
     
         9 . The battery cell of  claim 7 , wherein the wicking structure has a radial-spoked shaped cross section. 
     
     
         10 . The battery cell of  claim 7 , wherein the wicking structure has a cross-shaped cross section. 
     
     
         11 . The battery cell of  claim 7 , wherein the wicking structure comprises columns running along the vapor chamber. 
     
     
         12 . The battery cell of  claim 3 , wherein the stem includes a seal to a casing of the cell body. 
     
     
         13 . The battery cell of  claim 4 , wherein the vapor chamber includes a heat pipe casing formed from a heat pipe wall;
 wherein   the wicking structure comprises at least one vapor channel,   the vapor chamber is partially embedded in the cell body and partially extends out of the cell body, forming a stem,   the heat pipe casing is a heat conducting casing that surrounds and houses the wicking structure and extends inward of the cell body, and   the vapor chamber is connected to the cell body with a vapor-tight seal.   
     
     
         14 . The battery cell of  claim 13 , wherein the cell body includes an electrical connection cap and spiral wound electrodes, and the vapor chamber includes a working fluid, capable of undergoing phase changes between liquid and vapor phases. 
     
     
         15 . A method of heating the battery cell of  claim 3 , comprising: applying a heat source to the stem. 
     
     
         16 . A method of cooling the battery cell of  claim 3 , comprising: placing the stem in contact with a substance at a lower temperature than an internal temperature of the cell body. 
     
     
         17 . A method for transferring heat away from or into a battery cell, the battery cell having a cell body including a spiral wound electrode, and a vapor chamber embedded in the cell body, the method comprising:
 absorbing heat from the cell body, at an evaporation region of the vapor chamber, the vapor chamber at least partially embedded within the spiral wound electrode of the cell body;   evaporating a working fluid to a vapor by absorbed heat within the evaporation region of the vapor chamber; and   changing phase of the working fluid from liquid to the vapor from evaporation thus taking away the heat, and making the vapor proceed from the evaporation region to a condensation region by means of a pressure difference.   
     
     
         18 . The method of  claim 17 , further comprising changing phase of the working fluid from the vapor to liquid at the condensation region where the heat is released. 
     
     
         19 . The method of  claim 17 , the battery cell further having a wicking structure within the vapor chamber, the method further comprising making liquid working fluid flow to the evaporation region by capillary action provided by the wicking structure. 
     
     
         20 . The method of  claim 17 , wherein the vapor chamber is configured to transfer the heat between the interior of the cell body and a region external to the cell body.