A battery pack comprising: a pack housing; a base plate; at least two battery modules arranged such that the battery modules are located in a space defined between the pack housing and the base plate, each battery module including a plurality of battery cells or unit modules which can be charged and discharged; a first wall located at a first side of the base plate; a second wall located at a second side of the base plate; an external input terminal and an external output terminal (131 and 141) are located at both of the first wall and the second wall, the battery modules being connected to the external input and output terminals (131 and 141) in a state in which the battery modules are electrically connected in series or in parallel to each other; a capacitor (144, 145) which is present at the first or second wall (130 or 140) adjacent to a corresponding one of the external input and output terminals (131 or 141), the capacitor (144, 145) being electrically connected to said corresponding one of the external input and output terminals (131 or 141), and another capacitor (144, 145) which is present at the other of the first or second wall (140 or 130) adjacent to a corresponding another of the external input and output terminals (141 or 131), said another capacitor (144, 145) being electrically connected to said corresponding another of the external input and output terminals (141 or 131), wherein a battery disconnect unit (BDU, 190) is mounted between the battery modules and the second wall, and is electrically connected to the external input and output terminals (131 and 141) formed at the first wall and second wall via bus bars, wherein the battery modules are electrically connected to the external input and output terminals at the second wall via the battery disconnect unit (BDU, 190), and wherein the capacitors (144, 145) are grounded to the base plate via the first and second walls (130 and 140). a pack housing; a base plate; at least two battery modules arranged such that the battery modules are located in a space defined between the pack housing and the base plate, each battery module including a plurality of battery cells or unit modules which can be charged and discharged; a first wall located at a first side of the base plate; a second wall located at a second side of the base plate; an external input terminal and an external output terminal (131 and 141) are located at both of the first wall and the second wall, the battery modules being connected to the external input and output terminals (131 and 141) in a state in which the battery modules are electrically connected in series or in parallel to each other; a capacitor (144, 145) which is present at the first or second wall (130 or 140) adjacent to a corresponding one of the external input and output terminals (131 or 141), the capacitor (144, 145) being electrically connected to said corresponding one of the external input and output terminals (131 or 141), and another capacitor (144, 145) which is present at the other of the first or second wall (140 or 130) adjacent to a corresponding another of the external input and output terminals (141 or 131), said another capacitor (144, 145) being electrically connected to said corresponding another of the external input and output terminals (141 or 131), wherein a battery disconnect unit (BDU, 190) is mounted between the battery modules and the second wall, and is electrically connected to the external input and output terminals (131 and 141) formed at the first wall and second wall via bus bars, wherein the battery modules are electrically connected to the external input and output terminals at the second wall via the battery disconnect unit (BDU, 190), and wherein the capacitors (144, 145) are grounded to the base plate via the first and second walls (130 and 140).