The symbol 'Ah' stands for Ampere-hour, a unit of electric charge. It is used to indicate the capacity of a battery, including the amount of current a battery can deliver over a certain period.

When a battery is rated with a capacity of 100Ah, it means that theoretically, the battery can provide 100 amperes for one hour before it is fully discharged. In other words, it indicates the total charge that the battery can hold and the current it can deliver over a specific duration.

The Ah rating is an important specification when choosing a battery, as it indicates how much current a battery can deliver before it needs to be recharged. A battery with a higher Ah rating generally has a larger capacity and can deliver power for a longer time before needing to be recharged.

It is important to know that the actual usable capacity of a battery can depend on various factors, such as the load, environmental conditions, and the age of the battery. Therefore, it is advisable to consult the manufacturer's specific recommendations for optimal usage conditions and expected performance of the battery.