Electrochemical cell having sulfated electrochemically active material

Abstract

An active paste for an lead-acid electrochemical cell which in a preferred embodiment includes tin; a method of manufacturing the same; and an electrochemical cell utilizing the same. The tin may be a tin sulfate, tin oxide, or metallic tin. The active paste sandwiches a primarily lead film which may, but need not, also include tin, to form a positive electrode. One or more positive electrodes are interleafed with a number of negative electrodes, separated by a separator material. The assembly is placed in a container and electrolyte is introduced. In alternate embodiments, the paste may include some combination of antimony, arsenic, germanium, indium, selenium, gallium, tellurium or other semiconductor materials with or without tin compounds.

What is claimed is:  
     
         1 . A method of manufacturing a lead acid electrochemical cell, comprising: preparing a sulfated electrochemically active material to which has been added an oxide of lead, sulfuric acid and a tin-containing compound, said preparation step including introducing the tin-containing compound to the material subsequent to adding the sulfuric acid to the material; coating said electrochemically active material onto a first electrode of a first polarity; arranging said first electrode adjacent to a second electrode of a polarity opposite the first electrodes, the first electrode and second electrode being separated by a separator; and containing said first electrode, second electrode and separator in a container.  
     
     
         2 . The method of  claim 1 , wherein said tin-containing compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         3 . The method of  claim 2 , wherein said tin-containing compound includes SnSO 4 .  
     
     
         4 . The method of  claim 1 , wherein said electrochemically active material is approximately 0.001 to 5% SnSO 4  by weight.  
     
     
         5 . The method of  claim 4 , wherein said electrochemically active material is approximately 0.1 to 1% SnSO 4  by weight.  
     
     
         6 . The method of  claim 5 , wherein said electrochemically active material is approximately 0.3% SnSO 4  by weight.  
     
     
         7 . The method of  claim 1 , wherein said first electrode includes a material selected from the group consisting of substantially pure lead and a lead/tin alloy.  
     
     
         8 . The method of  claim 8 , wherein said first electrode is approximately 1 to 3% tin by weight.  
     
     
         9 . The method of  claim 8 , wherein said first electrode is approximately 0.5 to 1.5% tin by weight.  
     
     
         10 . A method of manufacturing a sulfated electrochemically active material for use in a lead acid electrochemical cell, comprising introducing sulfuric acid to an oxide of lead, and subsequently introducing a tin-containing compound.  
     
     
         11 . The method of  claim 10 , wherein said tin-containing compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         12 . A sulfated electrochemically active material for a lead acid electrochemical cell produced by introducing sulfuric acid to an oxide of lead and subsequently introducing a tin-containing compound.  
     
     
         13 . The material of  claim 12 , wherein said tin-containing compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         14 . An electrochemical cell, comprising: a first electrode of a first polarity, said first electrode being coated with a sulfated electrochemically active material to which has been added an oxide of lead, sulfuric acid and a tin-containing compound, said electrochemically active material being prepared by introducing the tin-containing compound to the material subsequent to introducing the sulfuric acid to the material; a second electrode of a polarity opposite the first electrode; and a separator between the first electrode and second electrode.  
     
     
         15 . The cell of  claim 14 , wherein said tin-containing compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         16 . The cell of  claim 15 , wherein said electrochemically-active material is approximately 0.001 to 5% to SnSO 4  by weight.  
     
     
         17 . The cell of  claim 16 , wherein said electrochemically active material is approximately 0.1 to 1% SnSO 4  by weight.  
     
     
         18 . The cell of  claim 17 , wherein said electrochemically active material is approximately 0.3% SnSO 4  by weight.  
     
     
         19 . The cell of  claim 14 , wherein said first electrode includes a material selected from the group consisting of substantially pure lead and a lead/tin alloy.  
     
     
         20 . The cell of  claim 19 , wherein said first electrode is approximately zero to 3% tin by weight.  
     
     
         21 . The cell of  claim 20 , wherein said first electrode is approximately 0.5 to 1.5% tin by weight.  
     
     
         22 . A method of manufacturing a lead acid electrochemical cell, comprising: preparing an unsulfated electrochemically active material to which has been added an oxide of lead and including a compound selected from the group consisting of tin, antimony, arsenic, germanium, indium, selenium, gallium, tellurium and other semiconductors; coating said electrochemically active material onto a first electrode of a first polarity; arranging said first electrode adjacent to a second electrode of a polarity opposite the first electrodes, the first electrode and second electrode being separated by a separator; and containing said first electrode, second electrode and separator in a container.  
     
     
         23 . The method of  claim 22 , wherein said compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         24 . The method of  claim 23 , wherein said compound includes SnSO 4 .  
     
     
         25 . The method of  claim 22 , wherein said electrochemically active material is approximately 0.001 to 5% SnSO 4  by weight.  
     
     
         26 . The method of  claim 25 , wherein said electrochemically active material is approximately 0.1 to 1% SnSO 4  by weight.  
     
     
         27 . The method of  claim 26 , wherein said electrochemically active material is approximately 0.3% SnSO 4  by weight.  
     
     
         28 . The method of  claim 22 , wherein said first electrode includes a material selected from the group consisting of substantially pure lead and a lead/tin alloy.  
     
     
         29 . The method of  claim 28 , wherein said first electrode is less than 3% tin by weight.  
     
     
         30 . The method of  claim 29 , wherein said first electrode is approximately 0.5 to 1.5% tin by weight.  
     
     
         31 . A method of manufacturing an unsulfated electrochemically active material for use in a lead acid electrochemical cell, comprising introducing an oxide of lead to water; and introducing a compound selected from the group consisting of tin, antimony, arsenic, germanium, indium, selenium, gallium, tellurium and other semiconductors.  
     
     
         32 . The method of  claim 31 , wherein said compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         33 . An unsulfated electrochemically active material for a lead acid electrochemical cell produced by introducing an oxide of lead to water; and introducing a compound selected from the group consisting of tin, antimony, arsenic, germanium, indium, selenium, gallium, tellurium and other semiconductors.  
     
     
         34 . The material of  claim 33 , wherein said compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         35 . An electrochemical cell, comprising: a first electrode of a first polarity; and a coating coated onto said first electrode, the coating including an unsulfated electrochemically active material to which has been added an oxide of lead and a compound selected from the group consisting of tin, antimony, arsenic, germanium, indium, selenium, gallium, tellurium and other semiconductors.  
     
     
         36 . The cell of  claim 35 , wherein said compound is selected from the group consisting of SnSO 4 , SnO, metallic tin, a tin(II) salt and a tin(IV) salt.  
     
     
         37 . The cell of  claim 36 , wherein said electrochemically active material is approximately 0.001 to 5% to SnSO 4  by weight.  
     
     
         38 . The cell of  claim 37 , wherein said electrochemically active material is approximately 0.1 to 1% SnSO 4  by weight.  
     
     
         39 . The cell of  claim 38 , wherein said electrochemically active material is approximately 0.3% SnSO 4  by weight.  
     
     
         40 . The cell of  claim 35 , wherein said first electrode includes a material selected from the group consisting of substantially pure lead and a lead/tin alloy.  
     
     
         41 . The cell of claim  40 , wherein said first electrode is approximately zero to 3% tin-by weight.  
     
     
         42 . The cell of claim  41 , wherein said first electrode is approximately 0.5 to 1.5% tin by weight.