Battery box body and battery cluster

The invention discloses a battery box and a battery cluster, the battery box comprises a box bottom wall part and a box side wall part integrally connected to the box bottom wall part, and the box side wall part and the box bottom wall part are enclosed to form a mounting groove; the box side wall part comprises a front wall part and a rear wall part which are oppositely arranged and distributed in the first direction. The box bottom wall part is connected with a cross beam part between the front wall part and the rear wall part; the mounting groove is separated by the cross beam part, and a battery cell groove for placing a battery cell is formed between the rear wall part and the cross beam part; through the arrangement, in the forming process of the battery box body, the mounting groove can be defined by the box bottom wall part and the box side wall parts, and meanwhile, the mounting groove is separated by the cross beam part to form the battery cell groove; compared with the prior art, the step of connec