| 摘要 |
PROBLEM TO BE SOLVED: To promote heat release of an FET element prepared in a circuit board used for a battery pack. SOLUTION: Openings 3b and 3c are formed in a base board 3a, bottom surfaces of a charge controlling FET 4 and discharge controlling FET 5 are made to counter the openings 3b and 3c respectively, the charge controlling FET 4 and discharge controlling FET 5 are arranged on the base board 3a, each terminal of the charge controlling FET 4 and discharge controlling FET 5 is electrically connected to lands 9a or 9i prepared on a front surface of the base board 3a to make a circuit board 3. After this, when the circuit board 3 is held in an exterior case consisting of an upper case 7 and lower case 8, the upper surface of the charge controlling FET 4 and discharge controlling FET 5 and the upper case are adhered by a high thermal conductivity adhesive, the bottom surface of the charge controlling FET 4 and discharge controlling FET 5 and the lower case are adhered by a high thermal conductivity adhesive through the openings 3a and 3b. The thermal conductivity of the high thermal conductivity adhesive is preferably at least 0.3 W/m*K. COPYRIGHT: (C)2009,JPO&INPIT |
