I want a tiny powerbank of about 1000 mAh
Ideal would be a lipstick type in which I can use a 14500.
A PB without a replaceable battery would be ok.
It’s for charging a low power device.
The PB shouldn’t shutdown if the device is full, but simply keep the device at 100% at all times.
The device is a streamer for my hearing aids.
I already have 21700 and 18650 versions which work perfect, but because it hangs on my neck I prefer something lighter. A 14500 will extend the battery life of the streamer beyond a full day, and that’s all I need.
You’re going to have 30% or more loss of energy while transferring power from one battery to another. And then you’re not going to be able to access the bottom 30% of that battery’s power. So what started out as potentially 1000 mHa you’d be lucky to get half of that capacity into your other device.
If you’ve got an 18350 put that in your 18650 power bank with a good wad of aluminum foil on the negative end of the battery to make up the gap to test.
Or test to prove that you can go more than 3 days with a 3,000 milliamp 18650.