A low level of electrolyte fluid will cause the battery to discharge quickly.

Inspect the electrolyte level at least once a week. If it is low, remove the caps and add enough distilled water to bring the level between the upper and lower level (illustration).
Do not overfill.
Examine the specific gravity of the electrolyte with a hydrometer, especially during cold weather. If it is low, recharge the battery.
Battery Maintenance
Battery RechargingMazda 6 Owners Manual: Pregnant Women and Persons with Serious Medical Conditions
Pregnant women should always wear seat belts. Ask your doctor for specific recommendations.
The lap belt should be worn SNUGLY AND AS LOW AS POSSIBLE OVER THE HIPS.
The shoulder belt should be worn across your shoulder properly, but never across the stomach area.
Persons with serious medical con ...
Mazda 6 Owners Manual: Battery
WARNING
Wash hands after handling the battery and related accessories: Battery
posts, terminals and related accessories contain lead and lead compounds, chemicals
known to the State of California to cause cancer and reproductive harm.
Read the following precautions
carefully before using th ...