High-energy-efficiency lithium battery monorail hoist locomotive and battery management system thereof

A battery management system for a high-efficiency lithium battery monorail hoist locomotive, applied to the high-efficiency lithium battery monorail hoist locomotive, comprising:

• a driving unit, a battery unit and a bearing trolley, wherein the bearing trolley is configured to bear cargoes, the battery unit is configured to output a power to the driving unit, the driving unit is configured to drive the monorail hoist locomotive to move, the battery unit comprises a battery management system, an ultra capacitor and a battery pack formed by a plurality of single cells, the battery management system is configured to obtain a minimum state of charge difference ΔSOCmin between the single cells in the battery pack, a state of charge SOCn of each of the single cells, a maximum state of charge SOCmax among the single cells and a minimum state of charge SOCmin among the single cells, the ultra capacitor and the battery pack are controlled by the battery management system to charge and discharge, n denotes a battery serial number, wherein the battery management system comprises a battery equalization unit, and when an equalization management is performed by the battery equalization unit, the battery management comprises following steps:
• S1, determining, according to a magnitude and a direction of a current of the battery pack, whether the battery pack is in a charging state or a discharging state;
• and obtaining the minimum state of charge difference ΔSOCmin of the single cells in the battery pack;
• and
• S2, performing, when the battery pack is in the charging state, a charging equalization on the single cells, firstly, obtaining, by the battery equalization unit, the state of charge SOCn of the each of the single cells and the maximum state of charge SOCmax among the single cells;
• charging, when the single cells satisfy |SOCn−SOCmax|>ΔSOCmin, that is, a corresponding single cell is required to be charged, the corresponding single cell required to be charged by the battery equalization unit through the ultra capacitor;
• and stopping, until the corresponding single cell required to be charged satisfies |SOCn−SOCmax|≤ΔSOCmin, the charging equalization;
• and
• performing, when the battery pack is in the discharging state, a discharging equalization on the single cells, firstly, obtaining, by the battery equalization unit, the state of charge SOCn of the each of the single cells and the minimum state of charge SOCmin among the single cells;
• discharging, when the single cells satisfy |SOCn−SOCmin|>ΔSOCmin, that is, a corresponding single cell is required to be discharged, the corresponding single cell required to be discharged by the battery equalization unit through the ultra capacitor;
• and stopping, until the corresponding single cell required to be discharged satisfies |SOCn−SOCmin|≤ΔSOCmin, the discharging equalization.