Apparatus for measuring the pressure inside a rechargeable electrochemical cell

An apparatus for accurately measuring the pressure within a rechargeable cell, said apparatus comprising:

• a frame for removably positioning a rechargeable cell in an upright orientation;
• a movable brace adapted to movably engage a first end of said rechargeable cell and to electrically communicate with a terminal of said rechargeable cell, said movable brace including a hollow needle, said hollow needle having a pointed end which is operatively directed toward one end of said rechargeable cell;
• a pressure transducer mounted on said movable brace in pressure transmissive communication with said hollow needle;
• means for controllably moving said movable brace relative to said fixed brace, whereby said hollow needle is adapted for insertion into and removal from said rechargeable cell;
• and
• an elastomeric O-ring adapted to seal the point of insertion of said hollow needle into said rechargeable cell.

A method for accurately measuring the pressure within a rechargeable battery during operation, said method including the steps of:

• securing said rechargeable cell in a fixed position;
• inserting a hollow needle into the head space of said rechargeable cell using a hollow needle;
• releasably sealing the point of insertion of said hollow needle;
• operatively disposing a pressure transducer in pressure transmissive communication with said hollow needle, said transducer adapted to provide an electrical signal corresponding to sensed pressure;
• and
• electrically operating said rechargeable cell, whereby the electrical signal provided by said transducer corresponds to the pressure inside said rechargeable cell.