(JP2000268791-A)   NOVELTY - The battery pack has a number of battery cells (1) stored side by side in a case (2). The case is formed of a bottomed trough in the form of a rectangular loop. The case has inner and outer wall portions (21,22) opposed to each other and a base portion (23) that connects the respective lower end portions of the wall portions. The inside space of the trough forms a cell storage space in which the battery cells are arranged in a looped line. A central space surrounded by the inner wall portion of the trough forms a hollow (6) that vertically penetrates the trough.    USE - For modern electro-vehicles, power-assisted bicycles, power tools, etc.    ADVANTAGE - The battery pack restrains a rise and variation in temperature of battery cells and ensures steady charging and reliable cell performance. The battery pack structure is highly resistant to external impact.    (CN1267093-A)   NOVELTY - The battery pack has a number of battery cells (1) stored side by side in a case (2). The case is formed of a bottomed trough in the form of a rectangular loop. The case has inner and outer wall portions (21,22) opposed to each other and a base portion (23) that connects the respective lower end portions of the wall portions. The inside space of the trough forms a cell storage space in which the battery cells are arranged in a looped line. A central space surrounded by the inner wall portion of the trough forms a hollow (6) that vertically penetrates the trough.    USE - For modern electro-vehicles, power-assisted bicycles, power tools, etc.    ADVANTAGE - The battery pack restrains a rise and variation in temperature of battery cells and ensures steady charging and reliable cell performance. The battery pack structure is highly resistant to external impact.    (JP2001118551-A)   NOVELTY - The battery pack has a number of battery cells (1) stored side by side in a case (2). The case is formed of a bottomed trough in the form of a rectangular loop. The case has inner and outer wall portions (21,22) opposed to each other and a base portion (23) that connects the respective lower end portions of the wall portions. The inside space of the trough forms a cell storage space in which the battery cells are arranged in a looped line. A central space surrounded by the inner wall portion of the trough forms a hollow (6) that vertically penetrates the trough.    USE - For modern electro-vehicles, power-assisted bicycles, power tools, etc.    ADVANTAGE - The battery pack restrains a rise and variation in temperature of battery cells and ensures steady charging and reliable cell performance. The battery pack structure is highly resistant to external impact.    (JP2001135287-A)   NOVELTY - The battery pack has a number of battery cells (1) stored side by side in a case (2). The case is formed of a bottomed trough in the form of a rectangular loop. The case has inner and outer wall portions (21,22) opposed to each other and a base portion (23) that connects the respective lower end portions of the wall portions. The inside space of the trough forms a cell storage space in which the battery cells are arranged in a looped line. A central space surrounded by the inner wall portion of the trough forms a hollow (6) that vertically penetrates the trough.    USE - For modern electro-vehicles, power-assisted bicycles, power tools, etc.    ADVANTAGE - The battery pack restrains a rise and variation in temperature of battery cells and ensures steady charging and reliable cell performance. The battery pack structure is highly resistant to external impact.    (JP2001135290-A)   NOVELTY - The battery pack has a number of battery cells (1) stored side by side in a case (2). The case is formed of a bottomed trough in the form of a rectangular loop. The case has inner and outer wall portions (21,22) opposed to each other and a base portion (23) that connects the respective lower end portions of the wall portions. The inside space of the trough forms a cell storage space in which the battery cells are arranged in a looped line. A central space surrounded by the inner wall portion of the trough forms a hollow (6) that vertically penetrates the trough.    USE - For modern electro-vehicles, power-assisted bicycles, power tools, etc.    ADVANTAGE - The battery pack restrains a rise and variation in temperature of battery cells and ensures steady charging and reliable cell performance. The battery pack structure is highly resistant to external impact.    (JP2001155701-A)   NOVELTY - The battery pack has a number of battery cells (1) stored side by side in a case (2). The case is formed of a bottomed trough in the form of a rectangular loop. The case has inner and outer wall portions (21,22) opposed to each other and a base portion (23) that connects the respective lower end portions of the wall portions. The inside space of the trough forms a cell storage space in which the battery cells are arranged in a looped line. A central space surrounded by the inner wall portion of the trough forms a hollow (6) that vertically penetrates the trough.    USE - For modern electro-vehicles, power-assisted bicycles, power tools, etc.    ADVANTAGE - The battery pack restrains a rise and variation in temperature of battery cells and ensures steady charging and reliable cell performance. The battery pack structure is highly resistant to external impact.