Secondary battery having casing for preventing volumetric expansion

A secondary battery, comprising:

• an electrode assembly having a positive electrode plate and a negative electrode plate, and further including a separator interposed between the positive and negative electrode plates;
• and
• a box shaped case having an open top and having an enclosure including four lateral sides defining a space for containing the electrode assembly and a bottom portion for sealing a lower space of the enclosure, the box shaped case being attached to a top to a cap assembly, the case having at least one element to compensate for and prevent volumetric expansion of the case that includes a first protruding portion and a second protruding portion, the first protruding portion being at least one square element arranged at a center portion of at least one of the four lateral sides of the box shaped case to compensate for and to prevent volumetric expansion, the at least one of the four lateral sides further including a peripheral portion surrounding said at least one square element;
• wherein the cap assembly is attached to the box shaped case to seal it;
• wherein the cap assembly includes a terminal portion electrically connected to the electrode assembly;
• wherein a thickness t1 of the at least one of the four lateral sides of the case at a location that corresponds to said at least one square element is identical to a thickness t2 of the peripheral portion of the at least one of the four lateral sides of the case at a location external to said at least one square element;
• and
• wherein said at least one square element is only arranged at the central portion of the at least one of the four lateral sides of the box shaped case,
• wherein the at least one square element protrudes further towards an exterior of the case than the peripheral portion of the at least one of the four lateral sides of the case, wherein the second protruding portion extending from corners of the at least one square element and along diagonal directions thereof.

A secondary battery, comprising:

• an electrode assembly having a positive electrode plate and a negative electrode plate, and further including a separator interposed between the positive and negative electrode plates;
• and
• a box shaped case having an open top and having an enclosure comprising four lateral sides and defining a space to contain the electrode assembly and a bottom portion to seal a lower space of the enclosure, the box shaped case being attached at a top to a cap assembly, the case having at least one element to compensate for and prevent volumetric expansion of the case that includes first and second protruding portions arranged at a center portion of one of the four lateral sides of the box shaped case, the one of the four lateral sides further including a peripheral portion surrounding the first and second protruding portions, wherein the first protruding portion to compensate for and to prevent volumetric expansion has a square shape and the second protruding portion to compensate for and to prevent volumetric expansion extends along diagonal directions of the one of the four lateral sides of the case to compensate for and to prevent volumetric expansion;
• wherein the cap assembly is attached to the case to seal the electrode assembly within the enclosure of the case;
• wherein the cap assembly includes a terminal portion electrically connected to the electrode assembly;
• wherein a thickness t1 of the one of the four lateral sides of the case at a location that corresponds to the first protruding portion and a thickness t3 of the one of the four lateral sides of the case at a location that corresponds to the second protruding portion are identical to a thickness t2 of the one of the four lateral sides of the case at a location that corresponds to the peripheral portion surrounding the first and second protruding portions;
• and
• wherein the first and second protruding portions are arranged only at the central portion of the one of the four lateral sides of the box shaped case,
• wherein each of the first and second protruding portions protrude towards an exterior of the case.

A secondary battery, comprising:

• an electrode assembly having a positive electrode plate and a negative electrode plate, and further including a separator interposed between the positive and negative electrode plates;
• and
• a case having an enclosure including four lateral sides in a shape of a box having an open top and a bottom to seal a lower space of the enclosure, the case being attached at a top thereof to a cap assembly, the case having at least one element to compensate for and prevent volumetric expansion of the case arranged at a center portion of one of the four lateral sides of the case, the one of the four lateral sides further including a peripheral portion surrounding said at least one element, said at least one element to compensate for and to prevent volumetric expansion including first and second elements arranged on the one of the four lateral sides of the case while being spaced-apart from each other;
• wherein the cap assembly is attached to the case to seal the electrode assembly within the enclosure of the case;
• wherein the cap assembly includes a terminal portion electrically connected to the electrode assembly;
• wherein a thickness t1 of the one of the four lateral sides of the case at a location that corresponds to said at least one element being identical to a thickness t2 of the one of the four lateral sides of the case at a location that corresponds to the peripheral portion surrounding said at least one element;
• and
• wherein the at least one element is arranged only at the central portion of the one of the four lateral sides of the case,
• wherein each of the first and second elements include first and second protruding portions that are protruding ridges, second protruding portion extending in a direction that forms an oblique angle with an extending direction of the first protruding portion along the one of the four lateral sides for each of the first and second elements.