Welded structure

1. A welded structure, comprising:

a first conductor which is plated with one of tin and a metal material having a melting point higher than that of the tin; and

a second conductor which is plated with the other of the tin and the metal material, has a thickness greater than that of the first conductor, and is formed with a protrusion which protrudes toward the first conductor on a part of a surface facing the first conductor at a time of being welded with the first conductor, wherein

a part of the first conductor located at a position opposite to the protrusion and a top of the protrusion of the second conductor are joined so that the first conductor and the second conductor are welded to each other by only a single weld.

2. The welded structure according to claim 1 , wherein

the metal material is nickel.

3. The welded structure according to claim 2 , wherein

the second conductor is a busbar which is connected to an electrode formed in a battery pack, and

the first conductor is a voltage detection terminal which is connected to the busbar for detecting a voltage of the electrode.

4. The welded structure according to claim 1 , wherein

the first conductor includes a terminal body portion, an electrical contact portion, a conductor connection portion, and a voltage detection conductor,

the electrical contact portion protrudes from the terminal body portion and is welded to the protrusion by only the single weld,

the conductor connection portion is crimped onto the voltage detection conductor, and is spaced away from the electrical contact portion by the terminal body portion.

5. The welded structure according to claim 1 , wherein

the first conductor has an electric contact portion with a tip end, and

the tip end of the electric contact portion is inclined toward the second conductor at the time of being welded.