Shop OBEX P1 Docs P2 Docs Learn Events
Battery life/ run time question — Parallax Forums

Battery life/ run time question

jdoleckijdolecki Posts: 726
edited 2011-08-28 12:01 in General Discussion
I have (2) 12V - 18Ah batteries in series.

The way i understand it is if I had a 1amp load the one battery should last 18 hours.

Does that apply even if the batteries are in series for 24v? I know the voltage doubles but what happens to the Amp hour rating?

thanks

John

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2011-08-28 12:01
    The Ampere-hours refers to the amount of current only. If your device draws 1A, an 18Ah battery will supply 1A for 18 hours. The voltage doesn't matter. If you're using a switching regulator, it's a little different. If you have two 12V (13.8V actually) 18Ah batteries in series and this feeds a switching regulator and the output of the switching regulator feeds a 1A load, the input to the switching regulator will draw a bit more than 1/2A, not 1A and the batteries in series should last for a bit less than 36 hours.
Sign In or Register to comment.