to charge this battery in this lift you will need a commercial (industrial) type battery charger. These standup/orderpicker type lifts use industrial type batteries with large cells.
An automotive charger will not work, it does not have enough amp hour rate to do it period.
Your best bet is to contact your local 'industrial' battery company and give them the information of the battery, size, amp rate, serial number and model number from the battery information that should be stamped on the case near the lifting ear on the outside, also on the shunt bars connecting the cells together there should be some information stamped into one of these connecting bars. You will have to remove the plastic cover to see it (if the plastic cover is still intact). This info should be near one end, probably near the positive cable end but check them all to be sure.
At minimum the least amp rate the charger would have to be to effectively charge this battery would be around 60ah rate but since i do not know the battery model number and amp capacity i'm guessing.