Raw material nuts may be quenched using an extremely low temperature liquefied gas to produce cracks in the raw material nuts. The working pressure of each safety valve is set so that the safety valve of at least one battery module is opened when the at least one battery module has its maximum internal pressure or less during the charge equalization. Each contact defines a connecting portion connecting with the pair of elastic arms and received in the passageway. Additionally the second client can retrieve event item data, corresponding to the event notification received from the first client, from the database where the event item is collected. In its set-up or voting state, the ballot box receives ballots from the tabulating machine and stores them in one or more secure ballot compartments.