Power lithium battery pack for electric vehicles usually use the structure of series battery string,since battery cells are not equal. So it is necessary for balance control during the battery charging and discharging process. A battery equalization method based on double-tiered quasi-resonant switched capacitor was presented in this paper,with the modification of the conventional double-tiered switched capacitor method,improved the use of quasi-resonant soft-switching to achieve zero-current switching on a...