Toro ProLine 30180 Operator's Manual page 21

POTENTIAL HAZARD
Charging battery produces gasses.
WHAT CAN HAPPEN
Battery gasses can explode.
HOW TO AVOID THE HAZARD
Keep cigarettes, sparks and flames away
from battery.
4. When the battery is fully charged, disconnect the
charger from the electrical outlet then from the
negative and positive battery posts (Fig. 16).
5. Slowly pour electrolyte into each cell until the
level is up to the lower part of the tube (Fig. 15)
and install covers.
6. Install the battery into the holder.
Set-Up
19