In this case, you should choose a lithium battery of about 32V.
If you replace the four 32mm batteries of the tricycle with lithium batteries , you should choose a lithium battery specification with similar voltage and capacity as the original battery. Since the original tricycle battery specification is 32V, you should choose a lithium battery specification of about 32V.
The capacity of the lithium battery should also be taken into account account. If the tricycle is used to carry or transport heavy objects, it is necessary to choose a larger capacity lithium battery to provide sufficient endurance and charging capacity. It is recommended to choose a lithium battery with a capacity between 100 Ah and 200 Ah.