Rechargeable lithium batteries can be used for clocks, but care needs to be taken to match the voltage and size. Because the watch power demand is small, the rechargeable lithium battery can provide long-term power support, avoiding the trouble of frequent battery replacement. At the same time, lithium batteries have the advantages of high energy density, lightweight, no memory effect, and are suitable for small electronic devices such as clocks and watches. However, when using lithium batteries, it is necessary to pay attention to correct charging and discharging, avoid overdischarge and overcharge, and extend the service life of the battery.