discharged battery? we used to start the car by push-starting it. if you have a battery charger, fast-charging for 5-10 minutes may be enough to have the car started. there is no need to charge the battery afterward. in modern cars, 30 minutes of normal daytime use afterwards, will adequately charge the battery. if the battery discharges again for no apparent reason, have the battery and the charging system checked.
nowadays, i use maintenance-free batteries. in our experience, we never had to maintain them until they naturally die after 24 months or more. also, there is no need to protect the overhead metal..