After long periods of storage (12 months or more) the battery will need to be recharged when the terminal voltage falls below the required voltage. When recharging, please keep yourself and your colleagues safe by following all the relevant safety recommendations (such as wearing protective glasses).
To charge an automotive battery, refer to your car owners’ manual and your battery charger manual for instructions. Review the safety instructions that came with your charger and battery. Remember that batteries contain sulphuric acid that can cause severe burns, and hydrogen-oxygen gases that can be explosive. Read the complete safety section on this website.
NEVER ATTEMPT TO CHARGE A BATTERY WITHOUT FIRST REVIEWING THE INSTRUCTIONS FOR THE CHARGER BEING USED. In addition to the charger manufacturer’s instructions, these general precautions should be followed:
Always wear proper eye, face and hand protection.
Always charge batteries in a well-ventilated area.
Keep vents tight and level.
Turn the charger and timer “OFF” before connecting the leads to the battery to avoid dangerous sparks.
Never try to charge a visibly damaged or frozen battery.
Connect the charger leads to the battery; red positive (+) lead to the positive (+) terminal and black negative (-) lead to the negative (-) terminal. If the battery is still in the vehicle, connect the negative lead to the engine block to serve as a ground. Be sure the ignition and all electrical accessories are turned off. (If the vehicle has a positive ground, connect the positive lead to the engine block.)
Make sure that the charger leads to the battery are not broken, frayed or loose.
Set the timer, turn the charger on and slowly increase the charging rate until the desired ampere value is reached.
If the battery becomes hot, or if violent gassing or spewing of electrolyte occurs, reduce the charging rate or turn off the charger temporarily.
Always turn the charger “OFF” before removing charger leads from the battery to avoid dangerous sparks.