We have a selection of batteries on eBay up for auction at the moment. All starting at $1 dollar and no reserve.
These are all batteries with issues and a brief description is available on each one. Some have bad temperature sensors or non-working Bluetooth, but otherwise work and function fine.
If you don't need low-temp protection, Bluetooth, or you're just into ripping apart batteries, then these are probably the best deals around!
Check out the listings... https://www.ebay.com/usr/ontegic