Sealing plate for prismatic secondary battery, method for producing the same, and prismatic secondary battery using the same

A prismatic secondary battery comprising:

• a prismatic hollow outer body having a mouth and a bottom;
• a flat electrode assembly including a positive electrode sheet and a negative electrode sheet;
• a positive electrode collector electrically connected to the positive electrode sheet;
• a negative electrode collector electrically connected to the negative electrode sheet;
• an electrolyte;
• a positive electrode terminal electrically connected to the positive electrode collector;
• a negative electrode terminal electrically connected to the negative electrode collector;
• a sealing plate sealing up the mouth of the prismatic outer body,
• the sealing plate including
• a front face;
• back face;
• and
• a pair of mouths comprising:
• a first mouth formed near one end in a longitudinal direction of the sealing plate, and
• a second mouth formed near the other end in the longitudinal direction of the sealing plate;
• a first coining area formed around the first mouth on the front face;
• a gas release valve and an electrolyte pour hole formed between the pair of mouths;
• a first long side edge;
• and
• a first groove formed on the front face from a position between the first coining area and the first long side edge to a position near the gas release valve along the first long side edge of the sealing plate;
• and
• a first insulating member attached to the first coning area,
• wherein one of the positive electrode terminal and the negative terminal electrode terminal is inserted into the first mouth.

A prismatic secondary battery comprising:

• a prismatic hollow outer body having a mouth and a bottom;
• a flat electrode assembly including a positive electrode sheet and a negative electrode sheet;
• a positive electrode collector electrically connected to the positive electrode sheet;
• a negative electrode collector electrically connected to the negative electrode sheet:
• an electrolyte;
• a positive electrode terminal electrically connected to the positive electrode collector;
• a negative electrode terminal electrically connected to the negative electrode collector;
• a sealing plate sealing up the mouth of the prismatic outer body,
• the sealing plate including
• a front face;
• a back face;
• and
• a pair of mouths comprising:
• a first mouth formed near one end in a longitudinal direction of the sealing plate, and
• a second mouth formed near the other end in the longitudinal direction of the sealing plate;
• a first coining area formed around the first mouth on the front face;
• a second coining area formed around the second mouth on the front face;
• a gas release valve and an electrolyte our hole formed between the pair of mouths;
• and
• a first groove formed on the front face;
• a second groove formed on the front face;
• a first long side edge;
• and
• a second long side edge,
• wherein
• the first long side edge and second long side edge are parallel,
• the first groove and the second groove stand apart from each other in a perpendicular direction to the first long side edge,
• the first groove is formed between the first long side edge and the first coining area, and
• the second groove is formed between the second long side edge and the first coining area.