1998 Lexus ES 300 Owners Manual - Page 223

ELECTRICAL COMPONENTS BATTERY RECHARGING PRECAUTIONS During recharging, the battery is producing hydrogen gas. Therefore, before recharging: 1. Maintenance type batteries - Remove the vent plugs. 2. If recharging with the battery installed on the vehicle, be sure to disconnect the ground cable. 3. Make sure the power switch on the recharger is off when connecting the charger cables to the battery and when disconnecting them. NOTICE Never recharge the battery while the engine is running. Also, be sure all accessories are turned off. CAUTION ¦ ¦ Always charge the battery in an unconfined area. Do not charge the battery in a garage or closed room where there is not sufficient ventilation. Non-maintenance batteries: Only do a slow charge (5 A or less). Charging at a quicker rate is dangerous. The battery may explode causing personal injuries. Maintenance type batteries: Be sure to remove the vent plugs before recharging. 223