A battery pack comprising an electrochemical cell comprising - a polyhedronal cell housing, the cell housing including a first end, a second end opposed to the first end, and a multi-sided sidewall that extends between the first end and the second end, - an electrode assembly disposed in the cell housing, the electrode assembly including positive electrode plates, negative electrode plates and separators (30, 32), the positive electrode plates stacked with the negative electrode plates, the separators (30, 32) disposed between the positive electrode plates and the negative electrode plates in a way that the stacked positive electrode plates alternating with the negative electrode plates are separated by intermediate separators (30, 32), the electrode assembly including a stack axis that extends in parallel to a stacking direction of the positive electrode plates, the negative electrode plates and the separators (30, 32), the stack axis extending parallel to the sidewall and perpendicular to the cell housing first and second ends (22, 23), wherein the positive electrode plates are stacked along the stack axis partially offset relative to the separator plates (30, 32), wherein one edge of each of the positive electrode plates extends beyond a corresponding edge (30a, 32a) of the separator plates (30, 32), - a current collector (70, 170, 270, 370, 470), the current collector (70, 170, 270, 370, 470) comprising a collection portion (72, 172, 272, 372, 472) disposed in the cell housing so as to reside between the electrode assembly and one side of the multi-sided sidewall, the collection portion (72, 172, 272, 372, 472) extending parallel to the one side and being electrically and thermally connected to the positive electrode plates, and a fin portion (78, 178, 278, 378, 486) that is disposed outside the cell housing, is electrically and thermally connected to the collection portion (72, 172, 272, 372, 472), extends in a direction parallel to the second end and overlies the second end, and a terminal disposed outside of the cell housing so as to overlie the one side and configured to provide one of heating and cooling, the terminal being electrically and thermally connected to the collection portion (72, 172, 272, 372, 472); characterized in that the polyhedronal cell housing is formed of a flexible laminate material; and the collection portion (72, 172, 272, 372, 472) is extending parallel to the stack axis and is electrically and thermally connected via direct contact to the peripheral edge of the positive electrode plates. - a polyhedronal cell housing, the cell housing including a first end, a second end opposed to the first end, and a multi-sided sidewall that extends between the first end and the second end, - an electrode assembly disposed in the cell housing, the electrode assembly including positive electrode plates, negative electrode plates and separators (30, 32), the positive electrode plates stacked with the negative electrode plates, the separators (30, 32) disposed between the positive electrode plates and the negative electrode plates in a way that the stacked positive electrode plates alternating with the negative electrode plates are separated by intermediate separators (30, 32), the electrode assembly including a stack axis that extends in parallel to a stacking direction of the positive electrode plates, the negative electrode plates and the separators (30, 32), the stack axis extending parallel to the sidewall and perpendicular to the cell housing first and second ends (22, 23), wherein the positive electrode plates are stacked along the stack axis partially offset relative to the separator plates (30, 32), wherein one edge of each of the positive electrode plates extends beyond a corresponding edge (30a, 32a) of the separator plates (30, 32), - a current collector (70, 170, 270, 370, 470), the current collector (70, 170, 270, 370, 470) comprising a collection portion (72, 172, 272, 372, 472) disposed in the cell housing so as to reside between the electrode assembly and one side of the multi-sided sidewall, the collection portion (72, 172, 272, 372, 472) extending parallel to the one side and being electrically and thermally connected to the positive electrode plates, and a fin portion (78, 178, 278, 378, 486) that is disposed outside the cell housing, is electrically and thermally connected to the collection portion (72, 172, 272, 372, 472), extends in a direction parallel to the second end and overlies the second end, and a collection portion (72, 172, 272, 372, 472) disposed in the cell housing so as to reside between the electrode assembly and one side of the multi-sided sidewall, the collection portion (72, 172, 272, 372, 472) extending parallel to the one side and being electrically and thermally connected to the positive electrode plates, and a fin portion (78, 178, 278, 378, 486) that is disposed outside the cell housing, is electrically and thermally connected to the collection portion (72, 172, 272, 372, 472), extends in a direction parallel to the second end and overlies the second end, and