Primary lithium electrochemical cell

Abstract

A primary electrochemical cell includes a cathode including lambda-manganese dioxide (λ-MnO 2 ), an anode including lithium or a lithium alloy, a separator interposed between the cathode and the anode, and a non-aqueous electrolyte contacting the anode and the cathode.

1 - 10 . (canceled)  
   
   
       11 . A method of preparing lambda-manganese dioxide comprising: 
 contacting water with a compound of the formula Li 1+x Mn 2−x O 4 , wherein x is from −0.02 to +0.02;    adding an acid to the water and compound until the water has a pH of 1 or less;    separating a solid from the water and acid; and    drying the solid at a temperature of 120° C. or below to obtain the lambda-manganese dioxide.    
   
   
       12 . The method of  claim 11 , wherein the compound has a BET surface area of between 1 and 10 m 2 /g.  
   
   
       13 . The method of  claim 11 , wherein the compound has a spinel-type crystal structure.  
   
   
       14 . The method of  claim 11 , wherein the solid is dried at a temperature between 30° C. to 90° C.  
   
   
       15 . The method of  claim 11 , wherein the solid is dried at a temperature between 50° C. and 70° C.  
   
   
       16 . The method of  claim 11 , wherein x is from −0.005 to +0.005.  
   
   
       17 . The method of  claim 11 , wherein contacting water and the compound includes forming a slurry.  
   
   
       18 . The method of  claim 17 , wherein the slurry is maintained at a temperature below 50° C.  
   
   
       19 . The method of  claim 11 , wherein the acid sulfueric acid, nitric acid, perchloric acid, hydrochloric acid, toluenesulfonic acid or trifluoromethylsulfonic acid.  
   
   
       20 . The method of  claim 17 , wherein the temperature of the slurry is held substantially constant during the addition of acid.  
   
   
       21 . The method of  claim 11 , wherein the pH is 0.7 or less.  
   
   
       22 . The method of  claim 11 , wherein the acid has a concentration of between 1 and 8 molar.  
   
   
       23 . The method of  claim 11 , further comprising washing the solid separated from the liquid phase with water until the washings have a pH of between 6 and 7.  
   
   
       24 - 25 . (canceled)