Why does the negative electrode of lithium batteries have to cover the positive electrode?

For example, when a power supply charges a battery, the electrons on the positive electrode pass from the positive electrode to the negative electrode via the external circuit. The positive lithium ions Li+ “jump” into the electrolyte from the positive electrode. and “climb” through the meanders of the diaphragm. The small hole "swims" to reach the negative electrode and combines with the electrons that have long passed it. If this is not covered, lithium precipitation and crystallization will occur and the consequences will be serious. .