In the 21st century, electrical vehicles saw resurgence due to the development of technology, and an increase focus on renewable energy. Inconsistency among the battery cells brings more challenges to manage lithium-ion battery. Typically, the individual cells in a battery pack may be at difference state of charge and have different capacities. That is why we need battery balancing. If without balancing functions, the battery can be easily overcharge or over-discharge, which means the individual cell voltage will differ over time and battery capacity will decrease quickly. These issues will limit the performance of lithium-ion battery. In order to shorten the research and development time of lithium-ion battery pack in the pre-phase, it is necessary to quickly charge and balance the battery pack during the laboratory test. This work focuses on design and development DCDC Isolated Battery Balancing and a Monitoring System for it which is used in laboratory research phase of lithium-ion battery. The isolated battery balancing proposed in this work is an isolated battery charging equalization equipment.