Cell sealant
AssigneeDuracell Inc.
InventorsDavid V. Adamson, Richard H. Dawson
Life of this patent
Estimating the term…
Abstract
The invention relates to sealant materials for sealing interfacial spaces within electrochemical cells. The sealant material is a thermoplastic block copolymer elastomer characterized by having at least two glass transition temperatures. The thermoplastic block copolymers form particularly useful sealants for a current collector nail which is inserted through an insulating closure member, such as a plastic grommet, used to close the open end of the cell.
Claims18
An electrochemical cell comprising an open ended cell casing;
- an anode active material;
- a cathode active material;
- a separator;
- and an electrolyte disposed in operative association within the cell casing;
- a closure member closing said open end;
- and a current collector member extending through an opening in said closure member so that a portion of the current collector penetrates into one of the anode and cathode active materials, wherein an interface is formed between the current collector member and the closure member;
- said cell further comprising a sealant material located within said interface, said sealant material consisting essentially of thermoplastic elastomeric material selected from the group consisting of styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), oil extended styrene-butadiene-styrene, styrene-ethylene/butylene-styrene (S-EB-S), styrene-ethylene/propylene-styrene (S-EP-S) and mixtures thereof.
An electrochemical cell comprising an open ended cell casing;
- an anode active material;
- a cathode active material and an electrolyte disposed within the cell casing;
- a closure member closing said open end;
- and a current collector member extending through an opening in said closure member so that a portion of the current collector penetrates into one of the anode and cathode active materials;
- wherein a first interface is formed between the current collector member and the closure member and a second interface is formed between said closure member and the casing;
- said cell further comprising a first sealant material located within said first interface;
- said first sealant material consisting essentially of thermoplastic elastomer selected from the group consisting of styrene-isoprene-styrene block copolymer and styrene-butadiene-styrene block copolymer and mixtures thereof.
An electrochemical cell comprising an open ended cell casing;
- an anode active material;
- a cathode active material and an electrolyte disposed within the cell casing;
- a closure member closing said open end;
- and a current collector member extending through an opening in said closure member so that a portion of the current collector penetrates into one of the anode and cathode active materials;
- wherein a first interface is formed between the current collector member and the closure member and a second interface is formed between said closure member and the casing;
- said cell further comprising a first sealant material located within said first interface;
- said first sealant material comprising a thermoplastic elastomer selected from the group consisting of styrene-isoprene-styrene block copolymer and styrene-butadiene-styrene block copolymer and mixtures thereof, said thermoplastic elastomer comprising between about 80 and 100 percent by weight of the first sealant material (as calculated on a solvent-free basis).
Dependencies are inferred from the claim text.