The application relates to a battery module, a battery pack and a vehicle. The battery module includes: secondary batteries, in which two or more secondary batteries are arranged side by side in an arrangement direction; a busbar arranged on a top of the secondary batteries and electrically connected to at least two of the secondary batteries; a sampling assembly including a sampling circuit board arranged on the top of the secondary batteries and a sampling leg extending from the sampling circuit board toward the busbar, the sampling leg and the busbar being welded to form a welded zone; a connector, the sampling leg and the busbar being connected by the connector, the connector being located at a side of the welded zone close to the sampling circuit board.