Battery terminal seal structure

Claim 1

In a high electrical energy low voltage battery comprising a sealed metallic can containing positive and negative electrodes and an electrical terminal hermetically sealed through said can and electrically connected to one of said electrodes the improvement wherein said electrical terminal comprises: (a) a first metallic sealing member having a first portion defining an annulus of given internal diameter, given external diameter and opposite substantially parallel surfaces and a second portion defining a right circular cylinder at the external periphery of said annulus defined by said first portion of said first metallic sealing member; (b) a second metallic sealing member having a first portion defining an annulus with opposite parallel surfaces having a given internal diameter and a given external diameter smaller than said given internal diameter of said annulus defined by said first portion of said first metallic sealing member and a second portion defining a right circular cylinder at the internal periphery thereof; (c) a first annular ceramic member having an internal diameter smaller than said given external diameter and larger than said given internal diameter of said annulus defined by said first portion of said second metallic sealing member and an external diameter larger than said given internal diameter of said annulus defined by said first portion of said first metallic sealing member; (d) a second annular ceramic member having an internal diameter smaller than said given internal and external diameters of said annulus defined by said first portion of said second metallic sealing member and an external diameter larger than said given internal diameter of said annulus defined by said first portion of said first metallic sealing member; (e) ceramic of metal seals bonding each of said opposite parallel surfaces of said annulus defined by said first portion of said first metallic sealing member to a different one of said first and second annular ceramic members; (f) ceramic to metal seals bonding each of said opposite parallel surfaces of said annulus defined by said first portion of said second metallic sealing member to a different one of said first and second annular ceramic members with said first annular ceramic member surrounding said right circular cylinder defined at the internal periphery of said second metallic sealing member in radially spaced relation thereto and with said annulus defined by said first portion of said second metallic sealing member in coaxial relation to said annulus defined by said first portion of said first metallic sealing member whereby said external and internal diameters respectively thereof are spaced from each other between said first and second annular ceramic members; and (g) a solid metallic rod received with said right circular cylinder defined by said second portion of said second metallic sealing member and hermetically bonded thereto, said internal diameter of said second annular ceramic member being dimensioned to receive said solid metallic rod with a small tolerance.