A battery module includes a plurality of batteries stacked together; a plate between adjacent ones of the batteries, the plate comprising a plate body; and a connecting tab extending from an edge of the plate body; and a first connection member extending along the batteries, wherein the first connection member has a coupling portion through which the connecting tab extends. The device includes a body having a body ear end, an opposite body user end, and a shaft extending from the ear end to the user end. The dynamic disambiguation threshold is used to determine whether to perform a first type of operation or a second type of operation when a first kind of gesture is detected.