NOVELTY - Battery pack comprises unit cell (1); circuit board (2) formed by connecting with electrode terminal of unit cell through lead (3) which consists of lead board (3A) or lead wire, and provides electroconductive part in surface of insulation base material (4); electronic circuit into which circuit board is connected; lands provided in surface of insulation base material and consisting of electroconductive part connected to unit cell through lead; and soldering clearance gap (7) provided between first and second lands (6A, 6B) and mutually connected with solder (30) provided with soldered lead.    USE - Battery pack used for power supplies, e.g. electric-power-assisted bicycle or electric scooter.    ADVANTAGE - The battery pack can effectively prevent peeling of land to which lead is soldered, and connects lead to land of circuit board for soldering.    DETAILED DESCRIPTION - Battery pack comprises unit cell (1) formed by mutually connecting in series; circuit board (2) formed by connecting with electrode terminal of unit cell through lead (3) which consists of lead board (3A) or lead wire, and provides electroconductive part in surface of insulation base material (4); electronic circuit mounted in electroconductive part and into which circuit board is connected; lands provided in surface of insulation base material and consisting of electroconductive part connected to unit cell through lead, in which land is used as segmentation land that consists of second land consisting of lead solder and is connected with first land formed by connecting with electronic circuit; and soldering clearance gap (7) provided between first and second lands (6A, 6B) and mutually connected with solder (30) provided with soldered lead. The segmentation land, first land, and second land are arranged on surface of insulation base material in non-connecting state. The circuit board is connected to second land and has through hole (8) into which lead is inserted and is soldered to second land. The first and second lands are provided in both sides of soldering clearance gap and are connected by solder formed by soldering lead to second land. The lead is connected with electronic circuit through first and second lands.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic sectional view of lead being soldered to circuit board (Drawing includes non-English language text).    Unit cell (1)    Circuit board (2)    Lead (3)    Lead board (3A)    Insulation base material (4)    Lands (6A, 6B)    Soldering clearance gap (7)    Through hole (8)    Solder (30)