This means that a battery has a 100 A.H. capacity if it is discharged over

**20 hours**, or at about 5 Amps-per-hour (100 A.H. /**20 hours**= 5 Amps DC). However, this same battery would last only**one hour**if the discharge rate was 50 Amps-per-hour (50 Amps DC x**1 hour**= 50 A.H.) because of the high rate of discharge.Similarly, it is asked, how long does it take to charge a 100ah battery?

If the applied Current is 10 Amperes, then it would be 100Ah/10A=

**10 hrs**approximately. It is an usual calculation. Discharging: Example: Battery AH X Battery Volt / Applied load. Say, 100 AH X 12V/ 100 Watts =**12 hrs**(with 40% loss at the max = 12 x 40 /100 =**4.8 hrs**) For sure, the backup will lasts up to**4.8 hrs**.How long 1.5 Ah battery will last?

2.0Ah 12V and 18v Battery Packs. As you might already know, Ah refers to the amp-hour rating of a battery. 1.5Ah means that a battery pack can deliver a steady 1.5 amps of current for

**one hour**. A tool that draws 0.75A from a 1.5Ah pack will have**two hours**of runtime, and one with a 3.0A draw will last for half an hour.