A modular connection board, which is configured to be attached to a group of electricity storage elements each including electrode terminals, the modular connection board comprising: at least two connection board modules, each of the at least two connection board modules comprising: a bracket including a plurality of connection member mounting portions, which are arranged to form a first row along one of a pair of first side edges of the connection board module, and to form a second row along the other one of the pair of first side edges of the connection board module, wherein the pair of first side edges of the connection board module extends in a first direction; a plurality of connection members, which are mounted in the plurality of connection member mounting portions, for connecting the electrode terminals of adjacent electricity storage elements to each other; and a circuit board supporting portion, which is arranged on the bracket and configured to receive a circuit board, wherein at least one holding element is arranged in the circuit board supporting portion, which is configured to hold the circuit board by a press-fit connection; wherein between each two adjacent connection board modules an interface is provided, which extends in a second direction different from the first direction, and which comprises at least one joint for joining the two adjacent connection board modules with each other. at least two connection board modules, each of the at least two connection board modules comprising: a bracket including a plurality of connection member mounting portions, which are arranged to form a first row along one of a pair of first side edges of the connection board module, and to form a second row along the other one of the pair of first side edges of the connection board module, wherein the pair of first side edges of the connection board module extends in a first direction; a plurality of connection members, which are mounted in the plurality of connection member mounting portions, for connecting the electrode terminals of adjacent electricity storage elements to each other; and a circuit board supporting portion, which is arranged on the bracket and configured to receive a circuit board, wherein at least one holding element is arranged in the circuit board supporting portion, which is configured to hold the circuit board by a press-fit connection; a bracket including a plurality of connection member mounting portions, which are arranged to form a first row along one of a pair of first side edges of the connection board module, and to form a second row along the other one of the pair of first side edges of the connection board module, wherein the pair of first side edges of the connection board module extends in a first direction; a plurality of connection members, which are mounted in the plurality of connection member mounting portions, for connecting the electrode terminals of adjacent electricity storage elements to each other; and a circuit board supporting portion, which is arranged on the bracket and configured to receive a circuit board, wherein at least one holding element is arranged in the circuit board supporting portion, which is configured to hold the circuit board by a press-fit connection; wherein between each two adjacent connection board modules an interface is provided, which extends in a second direction different from the first direction, and which comprises at least one joint for joining the two adjacent connection board modules with each other.