#AliExpress / cheap #Chinese goods / #questionable sellers, part 37:
1. Order #rechargeable 3-speed folding desk #fan.
2. Receive different version of same fan - no #electronics, no #battery, just a USB lead, it runs at one speed when plugged in, unplug it to turn off.
3. File "item not as described" ticket with photos clearly showing it's the wrong item.
4. AliExpress rejects ticket, the human who spent 0.3s reviewing it didn't read it and just clicked "#reject".
5. Edit #photos, adding big red "NO BATTERY HERE -->" and "NO ELECTRONICS HERE -->" etc and resubmit ticket.
6. AliExpress accepts claim this time. Get refund.
7. Place order for same rechargeable fan from different #seller.
8. Receive fan. #Charge. Give to partner.
"It turns off after a few seconds", she says.
Take it apart. Examine the circuit board, #probe it various ways, all looks good. #Measure #voltages. Manually #power the fan and see it draws half an #amp. See the suspiciously undersized lithium-ion #cell and think "they didn't just #cheap out so much that the thing doesn't work, did they?"...
Yup. The plastic casing has a slot & tabs arrangement inside sized for an 18650 cell, but they've got a much smaller cell in there with some padding to keep it in place. It's a 14500.
When the fan's on, the load is too much for the cell. The voltage drops enough that the little 3-speed management #chip thinks the cell is flat, and it turns off.
Put in a good 18650, runs like a charm.
Sheesh.
#LiIon