You will need
  • maintenance-free batteries, battery charger
Connect maintenance-free batteries to the charger. Check the polarity of the connection. Install controller minimum voltage. Turn on the charger. Set the voltage to 14.4 V. Such actions are subject to incomplete discharge of the battery.
During the process of charging current will gradually decrease. When the value of 0.2 A and the terminal voltage of battery 14.4 V charging is completed. This mode can not harm the battery.
Take maintenance-free batteries with deep discharge. When charging install low voltage – 12V - 13 V. make Sure the current at the beginning of the process corresponded to 1/20 of the capacity of the battery measured in hours. If you have more, reduce your stress. When charging current will gradually rise. When the value of 1/10 the battery's capacity should follow the item 1 charge.
In special cases, charging of the battery, you can give a charging current, which is equal to 1/5 of its capacity or more. It's not worth producing more than 20 minutes. Use a special charger.