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Kogan C9 Cordless Stick Vacuum Cleaner Battery $9.99.
Kogan C9 Cordless Stick Vacuum Cleaner Battery $9.99.
You should probably state what you plan to use them for. Batteries have different characteristics. There's high capacity ones, for weak things like a nightlight that might run for a long time. And then there's powerful ones to drive something big (like a powertool) for a short time.
Powertool or escooter level
LiitoKala Lii-35A 3500mAh 18650 batteries are what I use for a lot of projects. Despite the blown out shipping date I've had them arrive quicker.
So about $135 per kWh. Not really exciting if you want them for storage. Ok if you need that cell size.
OP, you're obviously battery savvy. If I don't want to muck around with Kogan first, where is the best place to buy good cells and what's a good benchmark price for 18650s?