Lithium ion battery pack pre-charging method for electric bicycle

The invention discloses a lithium ion battery pack pre-charging method for an electric bicycle, which comprises the following steps: S1, putting the electric bicycle into a battery-replacing lithium ion battery pack, and connecting a power converting harness with a transformer cabinet in electric signal connection; S3, charging the battery replacement lithium ion battery pack in the charging stateaccording to the placement state of the battery replacement lithium ion battery pack, the on-load state of the battery replacement lithium ion battery pack and the charging state of the battery replacement lithium ion battery pack; under the condition of battery replacement, instantaneous large current can be effectively avoided when the battery replacement lithium ion battery pack is connected with the electric bicycle through the arranged battery replacement cabinet and the power supply conversion wiring harness, so that the situation that a battery socket is burnt out is effectively avoided; and meanwhile, the ser