If you can't find the name, search for the part description (e.g., "replacement power cord for 3vt portable pump"). To help you find the exact piece, could you tell me:
Small handheld fans often use a single 18650 battery (3.7V). They are called "portable neck fans" or "mini desktop fans." A misspelling of "online portable 3.7V fan" could easily become "onlipelinet 3vt portable." onlipelinet 3vt portable