Cathodes and cathode mixtures including ozonated manganese dioxide

Abstract

Ozonated manganese dioxide is prepared by an ozonation process and utilized as a cathode active material. An ozone containing gas stream contacts manganese dioxide and produces ozonated manganese dioxide with high efficiency. After preparation, ozonated manganese dioxide is stored for a limited time at a low temperature and incorporated into a cathode active material for alkaline batteries.

1 . A method of making a cathode including ozonated manganese dioxide, the method comprising:
 contacting manganese dioxide that includes MnOOH with an ozone containing gas stream having an ozone concentration of at most 20 g/std m 3 , the ozone oxidizing the MnOOH to provide ozonated manganese dioxide; and   incorporating the ozonated manganese dioxide into a cathode.   
     
     
         2 . The method of  claim 1 , wherein the gas stream has an ozone concentration of at most 15 g/std m 3 . 
     
     
         3 . The method of  claim 1 , wherein the gas stream has an ozone concentration of about 5 g/std m 3  to about 15 g/std m 3 . 
     
     
         4 . The method of  claim 1 , wherein manganese in the ozonated manganese dioxide has an average valence value greater than 3.98. 
     
     
         5 . The method of  claim 1 , wherein the ozonated manganese dioxide is combined with carbon and an electrolyte to provide the cathode. 
     
     
         6 . The method of  claim 5 , wherein the carbon is selected from the group consisting of graphite, carbon black, and the combination thereof and the electrolyte is selected from the group consisting of saline electrolyte and alkaline electrolyte. 
     
     
         7 . The method of  claim 1 , wherein at least 30% of the ozone in the gas stream is consumed in the oxidation of the MnOOH. 
     
     
         8 . A method of making a cathode comprising ozonating manganese dioxide including MnOOH by contacting the manganese dioxide including MnOOH with an ozone containing gas stream, wherein the ozone oxidizes the MnOOH to provide ozonated manganese dioxide, and wherein at least 30% of the ozone in the gas stream is consumed in the oxidation of the MnOOH; and
 incorporating the ozonated manganese dioxide into a cathode.   
     
     
         9 . The method of  claim 8 , wherein at least 40% of the ozone in the gas stream is consumed in the oxidation of the MnOOH. 
     
     
         10 . The method of  claim 8 , wherein the ozonated electrolytic manganese dioxide is combined with carbon and an electrolyte to provide the cathode. 
     
     
         11 . A method of making a cathode mixture, the method comprising:
 combining ozonated manganese dioxide that has been prepared by an ozonation process with carbon and an electrolyte within 48 hours after the ozonation process has completed.   
     
     
         12 . The method of  claim 11 , comprising combining the ozonated manganese dioxide with carbon and the electrolyte within 36 hours. 
     
     
         13 . The method of  claim 11 , comprising combining the ozonated manganese dioxide with carbon and the electrolyte within 24 hours. 
     
     
         14 . The method of  claim 11 , comprising combining the ozonated manganese dioxide with carbon and the electrolyte within 12 hours. 
     
     
         15 . The method of  claim 11 , comprising storing the ozonated manganese dioxide at a temperature lower than about 30° C. before combining the ozonated manganese dioxide with carbon and the electrolyte. 
     
     
         16 . The method of  claim 15 , comprising storing the ozonated manganese dioxide at a temperature of about −10° C. to about 25° C. before combining the ozonated manganese dioxide with graphite and the electrolyte. 
     
     
         17 . The method of  claim 15 , comprising preparing the ozonated manganese dioxide by contacting manganese dioxide with an ozone containing gas stream during the ozonation process. 
     
     
         18 . A method of making a cathode mixture, the method comprising:
 storing ozonated manganese dioxide, prepared by an ozonation process, below 25° C.; and   after storage, combining the ozonated manganese dioxide with graphite and an electrolyte.   
     
     
         19 . The method of  claim 18 , comprising storing the ozonated manganese dioxide below 10° C. 
     
     
         20 . The method of  claim 18 , comprising storing the ozonated manganese dioxide below 5° C. 
     
     
         21 . The method of  claim 18 , comprising storing the ozonated manganese dioxide below 0° C. 
     
     
         22 . The method of  claim 18 , further comprising incorporating the combined ozonated manganese dioxide, carbon, and electrolyte into a cathode.