The invention discloses a battery collecting device and monitoring method. The battery collecting device comprises a first isolator, a second isolator, a battery control plate (BCU), a battery collecting plate (BMU), and a battery module. The battery module is connected to the BCU through a collecting wire harness. The BMU is in communication connection with the BCU through a CAN signal. The CAN signal passes through the first isolator or the second isolator. The BMU includes an analog front end collecting unit (AFE), a master controller unit (MCU), a fault alarm unit, a reset module, a waking-up unit, and a synchronous signal triggering unit. The invention is advantageous in that under non-work state, the BMU can collect battery information regularly, and can trigger alarm in time when abnormity occurs; real-time monitoring and management can be conducted on the battery; simple and effective resetting can be realized during the waking-up process of the BMU, the situation of system program abnormity can be reduced.