About to buy a Falcon Flo Foldable electric bike without a battery but the manufacturer Tandem does not provide replacement batteries , help!!!
My advice would be not to unless you're competent at electrical repairs and modifications.
The problem with those folding bikes is that they all use standard batteries, but the plastic end is different on nearly every one. Basically, it needs to fit the connector on the controller side, the lock mechanism and the charge socket. Without the original battery as a pattern, it would be difficult to figure out which one you need.
If you have the original one not working, you can transfer the end from one to another to make it fit.
You could try asking the manufacturer for a picture of the battery so that you can see what the connecting end looks like. You also need the length and cross section dimensions, though you could probably get them by gauging the frame.