How many lithium batteries can be connected in series?

Lithium battery pack 48V20AH generally single lithium battery is 3.5V, so 48V lithium battery pack needs 48/3.5=13.7, just take 14 in series. If the manufacturer has provided a set of 12V lithium batteries, then 4 can be connected in series. As long as the output voltage is 48V, the current is 2A or 4A.

How many watts a battery can be discharged in one hour?

2 batteries of 1000 mAh,1.5 V in series will have a global voltage of 3V and a current of 1000 mA if they are discharged in one hour. Capacity in Ampere-hour of the system will be 1000 mAh (in a 3 V system). In Wh it will give 3V*1A = 3 Wh

What happens if you discharge a battery in one hour?

Generally, for a given capacity you will have less energy if you discharge in one hour than if you discharge in 20 hours, reversely you will store less energy in a battery with a current charge of 100 A during 1 h than with a current charge of 10 A during 10 h. This phenomenon is significant for Lead batteries, much less for lithium batteries.