Heat storage device and air conditioner having same

A heat storage device is disposed around and held in contact with a compressor 6. The heat storage device includes a heat storage tank 32 for accommodating a heat storage material to store heat generated by the compressor 6 and a heat storage heat exchanger 34 accommodated within the heat storage tank 32. The heat storage tank 32 is disposed around the compressor 6 so as to be held in contact therewith and has a cutout portion along an outer circumference of the compressor 6 in contact with the heat storage tank 32. The heat storage tank 32 also has opposite end portions 46, 47 confronting the cutout portion and at least one of the end portions 46, 47 is thickened as compared with a thinnest portion of the heat storage tank 32, thereby making it possible to secure a predetermined volume while realizing space saving.