Charging the Battery
The battery can normally be recharged by means of a conventional battery charger.
2 If boost-charging is used, the charging current should not exceed 50 A.
Important: Do not boost-charge the battery if its voltage is less than 12 V or if it is more than two years old.
3 If the battery is almost fully discharged, because a lamp or other item of electrical equipment has been left on for a relatively long time, a low initial charge is required to start the chemical process in the battery.
In such cases, start charging the battery at 3 A (never more than 5 A) for 24 hours or until the charging current has dropped to its lowest stable value.
The battery will start to generate gas at 14.4 V. If the battery is to be charged with a higher voltage it must be cooled down.
A battery charger delivering a pulsating charging current should preferably be used in the above case.