Memory controller adjusting power, memory system including same, and operating method for memory system

An operating method for a memory system including a host and a memory system. The operating method may include; communicating maximum power information from the memory system to the host, communicating power table information and battery information from the host to the memory system in response to the maximum power information, and controlling power consumption by a component of the memory system in response to a maximum consumption power value, wherein each of the power table information and the battery information is related to a battery associated with the memory system and operating in accordance with battery steps, the power table information includes a number of entries including a first entry and a second entry, the first entry is related to a first battery step among the battery steps and associated with a first maximum consumption power value, the second entry is related to a second battery step among the battery steps and associated with a second maximum consumption power value, and the maximum consumption power value controlling power consumption by the component of the memory system is one of the first maximum consumption power value and the second maximum consumption power value.