Abstract: A battery module includes battery cells being arrayed, a cell-monitoring unit configured to monitor each battery cell of the battery module, a battery cell side circuit board electrically connected to the battery cells, and a cell-monitoring unit side circuit board electrically connected to the cell-monitoring unit and the battery cell side circuit board. The battery cell side circuit board and the cell-monitoring unit side circuit board are connected to each other and voltage detection lines on the battery cell side circuit board and a voltage detection lines on the cell-monitoring unit side circuit board are electrically connected. The electric circuits of the voltage detection lines on the battery cell side circuit board are aligned in order of their electric potentials and the electric circuits of the voltage detection lines on the cell-monitoring unit side circuit board are aligned in order of their electric potentials.

Abstract: A battery module includes battery cells being arrayed, a cell-monitoring unit configured to monitor each battery cell of the battery module, a battery cell side circuit board electrically connected to the battery cells, and a cell-monitoring unit side circuit board electrically connected to the cell-monitoring unit and the battery cell side circuit board. The battery cell side circuit board and the cell-monitoring unit side circuit board are connected to each other and voltage detection lines on the battery cell side circuit board and a voltage detection lines on the cell-monitoring unit side circuit board are electrically connected. The electric circuits of the voltage detection lines on the battery cell side circuit board are aligned in order of their electric potentials and the electric circuits of the voltage detection lines on the cell-monitoring unit side circuit board are aligned in order of their electric potentials.

Abstract: A helmet body is mounted or fixed detachably or undetachably a hollow molding or a ceramic-fixed hollow molding to enhance the impact resistance of the helmet body and weight-save the composite helmet, thereby increasing the adaptability. The composite helmet has excellent impact resistance. The outer surface of the helmet body is composed of a plastic or a metal and is mounted or fixed with a hollow molding having an external, truncated pyramid or cone shape so that the external shape of the hollow molding becomes similar to the external shape of the helmet body. It is preferable that the hollow molding has such a shape that at least two kinds of the starting hollow moldings having different, external, truncated pyramid or cone shapes are put one on another and integrally bonded so as to make the integrated boundary surface smooth and make the external shape of the resulting hollow molding more similar to the external shape of the helmet body.

Abstract: In this invention, on a helmet body is mounted or fixed detachably or undetachably a hollow molding or a ceramic-fixed hollow molding to enhance the impact resistance of the helmet body and weight-save the composite helmet, thereby increasing the adaptability.