Evaluation method and evaluation apparatus for evaluating battery safety, and battery whose safety indices have been determined with the same

An evaluation apparatus for evaluating safety of a battery comprising an electrode group including a positive electrode plate, a negative electrode plate and a separator inserted between said electrode plates, said apparatus comprising:

• a container for holding an electrolyte for immersing said battery that has been charged to a predetermined voltage and into which conductive foreign matter has been incorporated such that said conductive foreign matter is in contact with said positive electrode plate, and not in contact with said negative electrode plate;
• a dissolution start time determination means for determining a time at which said conductive foreign matter incorporated into said battery started to dissolve in said electrolyte;
• a short circuit occurrence detection means for detecting occurrence of an internal short circuit in said battery;
• a short circuit occurrence time computation means for computing a time required from start of dissolution of said conductive foreign matter in said electrolyte until occurrence of said internal short circuit, based on a determination result of said dissolution start time determination means and a detection result of said short circuit occurrence detection means;
• a heat generation level detection means for detecting a level of heat generation in said battery that is caused by said internal short circuit;
• and
• a safety index output means for outputting a computation result of said short circuit occurrence time computation means and a detection result of said heat generation level detection means as safety indices.